Telit Communications S p A LE940B6NA LE940B6-NA User Manual

Telit Communications S.p.A. LE940B6-NA

UserManual.wiki >

Telit Communications S p A >

LE940B6NA User Manual HTML Version

User Manual

LE940B6

Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

2 of 104

This documentation applies to the following products:

Table 1: Applicability Table

Module Name Description

LE940B6-NA AUTO North America regional variant (AT&T and T-Mobile)

LE940B6-NV AUTO North America region variant (Verizon, AT&T and T-Mobile)

LE940B6-RW AUTO Rest of World variant (Europe, APAC, Latin America and more)

LE940B6-CN AUTO China variant

Note: NV variant - to be developed

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

3 of 104

SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE

Notice

While reasonable efforts have been made to assure the accuracy of this document, Telit assumes

no liability resulting from any inaccuracies or omissions in this document, or from use of the

information obtained herein. The information in this document has been carefully checked and is

believed to be entirely reliable. However, no responsibility is assumed for inaccuracies or omissions.

Telit reserves the right to make changes to any products described herein and reserves the right to

revise this document and to make changes from time to time in the content hereof with no

obligation to notify any person of revisions or changes. Telit does not assume any liability arising

out of the application or use of any product, software, or circuit described herein; neither does it

convey any license under its patent rights or the rights of others.

It is possible that this publication may contain references to, or information about Telit products

(machines and programs), programming, or services that are not announced in your country. Such

references or information must not be construed to mean that Telit intends to announce such Telit

products, programming, or services in your country.

Copyrights

This instruction manual and the Telit products described in this instruction manual may be, include,

or describe copyrighted Telit material, such as computer programs stored in semiconductor

memories or other media. Laws in Italy and other countries preserve for Telit and its licensors

certain exclusive rights for copyrighted material, including the exclusive right to copy, reproduce in

any form, distribute, and make derivative works of the copyrighted material. Accordingly, any

copyrighted material of Telit and its licensors contained herein or in the Telit products described in

this instruction manual may not be copied, reproduced, distributed, merged, or modified in any

manner without the express written permission of Telit. Furthermore, the purchase of Telit

products shall not be deemed to grant either directly or by implication, estoppel, or otherwise, any

license under the copyrights, patents or patent applications of Telit, as arises by operation of law

in the sale of a product.

Computer Software Copyrights

Telit and third-party software (SW) products described in this instruction manual may include

copyrighted Telit and other third-party computer programs stored in semiconductor memories or

other media. Laws in Italy and other countries preserve for Telit and other third-party SW certain

exclusive rights for copyrighted computer programs, including the exclusive right to copy or

reproduce in any form the copyrighted computer program. Accordingly, any copyrighted Telit or

other third-party SW computer programs contained in the Telit products described in this

instruction manual may not be copied (reverse engineered) or reproduced in any manner without

the express written permission of Telit or the third-party SW supplier. Furthermore, the purchase

of Telit products shall not be deemed to grant either directly or by implication, estoppel, or

otherwise, any license under the copyrights, patents or patent applications of Telit or other third-

party SW, except for the normal non-exclusive, royalty free license to use that arises by operation

of law in the sale of a product.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

4 of 104

Usage and Disclosure Restrictions

License Agreements

The software described in this document is the property of Telit and its licensors. It is furnished by

an express license agreement only and may be used only in accordance with the terms of such an

agreement.

Copyrighted Materials

Software and documentation are copyrighted materials. Making unauthorized copies is prohibited

by law. No part of the software or documentation may be reproduced, transmitted, transcribed,

stored in a retrieval system, or translated into any language or computer language, in any form or

by any means, without prior written permission of Telit.

High Risk Materials

Components, units, or third-party products used in the product described herein are NOT fault-

tolerant and are NOT designed, manufactured, or intended for use as on-line control equipment in

the following hazardous environments requiring fail-safe controls: the operation of nuclear

facilities, aircraft navigation or aircraft communication systems, air traffic control, life support, or

weapons systems (“high risk activities"). Telit and its supplier(s) specifically disclaim any expressed

or implied warranty of fitness for such high risk activities.

Trademarks

TELIT and the stylized T logo are trademarks and/or registered trademarks of Telit Communications

S.p.A. in the Unites States and/or other countries. All other product or service names are the

property of their respective owners.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

5 of 104

Contents

Introduction ..................................................................................................... 12

1.1.

Scope ................................................................................................................ 12

1.2.

Audience .......................................................................................................... 12

1.3.

Contact Information, Support .......................................................................... 12

1.4.

Text Conventions ............................................................................................. 13

1.5.

Related Documents .......................................................................................... 14

1.6.

Abbreviations ................................................................................................... 14

1.7.

Document Organization ................................................................................... 15

General Product Description ............................................................................ 17

2.1.

Overview .......................................................................................................... 17

2.2.

Applications ..................................................................................................... 17

2.3.

General Functionality and Main Features ....................................................... 18

2.4.

Environmental Requirements .......................................................................... 19

2.4.1.

Temperature Range .............................................................................. 19

2.4.2.

RoHS Compliance.................................................................................. 19

2.5.

Operating Frequency Bands............................................................................. 20

2.5.1.

RF Bands per Regional Variant ............................................................. 20

2.5.2.

Reference Table of RF Bands Characteristics ....................................... 21

2.6.

Sensitivity ......................................................................................................... 24

2.7.

LE940B6 Mechanical Specifications ................................................................. 25

2.7.1.

Dimensions ........................................................................................... 25

2.7.2.

Weight .................................................................................................. 25

LE940B6 Module Connections .......................................................................... 26

3.1.

Pin-out .............................................................................................................. 26

3.2.

LE940B6 Signals That Must Be Connected ...................................................... 36

3.3.

LGA Pads Layout ............................................................................................... 38

Electrical Specifications .................................................................................... 39

4.1.

Absolute Maximum Ratings – Not Operational ............................................... 39

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

6 of 104

4.2.

Recommended Operating Conditions ............................................................. 39

4.3.

Logic Level Specifications ................................................................................. 40

4.3.1.

1.8V Standard GPIOs ............................................................................ 40

4.3.2.

1.8V I2C Pads ........................................................................................ 41

4.3.3.

1.2V EMIC Pads ..................................................................................... 41

4.3.4.

1.8V/2.9V SIM Pads .............................................................................. 42

4.3.5.

USB........................................................................................................ 42

4.3.6.

2.5V/3.3V EMAC Interface for RMII and RGMII ................................... 43

Hardware Commands ....................................................................................... 44

5.1.

Turning on the LE940B6 Module ..................................................................... 44

5.2.

Initialization and Activation State .................................................................... 44

5.3.

Turning off the LE940B6 Module ..................................................................... 48

5.3.1.

Shutdown by Software Command ....................................................... 48

5.3.2.

Hardware Shutdown ............................................................................. 50

5.3.3.

Unconditional Hardware Reset (RESET_N)........................................... 51

5.3.4.

Unconditional Hardware Shutdown ..................................................... 52

Power Supply ................................................................................................... 54

6.1.

Power Supply Requirements............................................................................ 54

6.2.

General Design Rules ....................................................................................... 57

6.2.1.

Electrical Design Guidelines .................................................................. 57

6.2.1.1.

+ 5V Input Source Power Supply – Design Guidelines ......... 57

6.2.1.2.

+ 12V Input Source Power Supply – Design Guidelines ....... 58

6.2.1.3.

Battery Source Power Supply – Design Guidelines .............. 60

6.2.2.

Thermal Design Guidelines ................................................................... 61

6.2.3.

Power Supply PCB Layout Guidelines ................................................... 61

Antenna(s) ....................................................................................................... 63

7.1.

GSM/WCDMA/TD-SCDMA/LTE Antenna Requirements ................................. 63

7.2.

GSM/WCDMA/TD-SCDMA/LTE Antenna – PCB Line Guidelines ..................... 63

7.3.

GSM/WCDMA/TD-SCDMA/LTE Antenna – Installation Guidelines ................. 65

7.4.

Secondary Antenna Requirements .................................................................. 65

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

7 of 104

7.5.

PCB Guidelines in case of FCC certification ..................................................... 65

7.5.1.

Transmission line design....................................................................... 65

7.5.2.

Transmission line measurements ......................................................... 66

Hardware Interfaces......................................................................................... 69

8.1.

USB Port ........................................................................................................... 70

8.2.

Serial Ports ....................................................................................................... 71

8.2.1.

Modem Serial Port 1 ............................................................................. 72

8.2.2.

Modem Serial Port 2 ............................................................................. 73

8.2.3.

Modem Serial Port 3 ............................................................................. 73

8.2.4.

RS232 Level Translation ........................................................................ 74

8.3.

Peripheral Ports ............................................................................................... 76

8.3.1.

SPI – Serial Peripheral Interface ........................................................... 76

8.3.2.

I2C - Inter-integrated Circuit ................................................................ 77

8.4.

Ethernet Interface ............................................................................................ 77

8.5.

Audio Interface ................................................................................................ 78

8.5.1.

Analog Audio ........................................................................................ 78

8.5.2.

Digital Audio ......................................................................................... 79

8.6.

General Purpose I/O ........................................................................................ 79

8.6.1.

Using a GPIO Pad as Input .................................................................... 80

8.6.2.

Using a GPIO Pad as Output ................................................................. 80

Miscellaneous Functions .................................................................................. 82

9.1.

Indication of Network Service Availability ....................................................... 82

9.2.

RTC – Real Time Clock ...................................................................................... 83

9.3.

VAUX Power Output ........................................................................................ 83

9.4.

ADC Converter ................................................................................................. 83

9.4.1.

Description............................................................................................ 83

9.4.2.

Using the ADC Converter ...................................................................... 83

9.5.

Using the Temperature Monitor Function ...................................................... 84

9.6.

Fuel Gauge (TBD) ............................................................................................. 84

9.7.

eFuse ................................................................................................................ 84

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

8 of 104

10.

Mounting the Module on your Board ............................................................... 85

10.1.

General ............................................................................................................. 85

10.2.

Finishing & Dimensions .................................................................................... 85

10.3.

Recommended Footprint for the Application ................................................. 86

10.4.

Stencil ............................................................................................................... 87

10.5.

PCB Pad Design ................................................................................................ 87

10.6.

Recommendations for PCB Pad Dimensions (mm) .......................................... 88

10.7.

Solder Paste ..................................................................................................... 89

10.7.1.

Solder Reflow ........................................................................................ 89

11.

Application Guide ............................................................................................ 91

11.1.

Debug of the LE940B6 Module in Production ................................................. 91

11.2.

Bypass Capacitor on Power Supplies ............................................................... 92

11.3.

SIM Interface .................................................................................................... 93

11.3.1.

SIM Schematic Example ........................................................................ 93

11.4.

EMC Recommendations ................................................................................... 94

11.5.

Download and Debug Port ............................................................................... 94

11.6.

Antenna Detection ........................................................................................... 95

12.

Packing System ................................................................................................ 96

12.1.

Tray Drawing .................................................................................................... 98

12.2.

Moisture Sensitivity ......................................................................................... 98

13.

Conformity Assessment Issues ......................................................................... 99

13.1.

FCC/IC Regulatory Notices ............................................................................... 99

14.

Safety Recommendations ................................................................................ 101

15.

Document History ........................................................................................... 102

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

9 of 104

List of Tables

Table 1: Applicability Table ................................................................................................................. 2

Table 2: Related Documents ............................................................................................................ 14

Table 3: Document Structure ........................................................................................................... 15

Table 4: RF Bands per Regional Variant ............................................................................................ 20

Table 5: RF Bands Characteristics ..................................................................................................... 21

Table 6: LE940B6 Pin-out .................................................................................................................. 26

Table 7: Mandatory Signals .............................................................................................................. 36

Table 8: Absolute Maximum Ratings – Not Operational .................................................................. 39

Table 9: Recommended Operating Conditions ................................................................................ 39

Table 10: Absolute Maximum Ratings – Not Functional .................................................................. 40

Table 11: Operating Range – Interface Levels (1.8V CMOS) ............................................................ 40

Table 12: Operating Range – 1.8V I2C Pads ..................................................................................... 41

Table 13: Operating Range – 1.2V EMIC Pads .................................................................................. 41

Table 14: Operating Range – 1.8V SIM Pads .................................................................................... 42

Table 15: Operating Range – 2.9V SIM Pads .................................................................................... 42

Table 16: Operating Range – USB_D+, USB_D- Pads ........................................................................ 42

Table 17: Absolute Maximum Ratings – 3.3V EMAC Interface......................................................... 43

Table 18: Operating Range – 2.5V EMAC Interface .......................................................................... 43

Table 19: Operating Range – 3.3V EMAC Interface .......................................................................... 43

Table 20: Power Supply Requirements ............................................................................................ 54

Table 21: LE940B6 Current Consumption ........................................................................................ 54

Table 22: Primary Antenna Requirements ...................................................................................... 63

Table 23: Antenna Line on PCB Requirements ................................................................................. 64

Table 24: LE940B6 Hardware Interfaces .......................................................................................... 69

Table 25: USB Interface Signals ........................................................................................................ 70

Table 26: Modem Serial Port 1 Signals ............................................................................................. 72

Table 27: Modem Serial Port 2 Signals ............................................................................................. 73

Table 28: Modem Serial Port 3 Signals ............................................................................................. 73

Table 29: SPI Signals ......................................................................................................................... 76

Table 30: Ethernet Interface ............................................................................................................. 77

Table 31: Analog Audio Signals ......................................................................................................... 78

Table 32: Digital Audio Interface (DVI) Signals ................................................................................. 79

Table 33: GPIOs ................................................................................................................................ 79

Table 34: Network Service Availability Indication ............................................................................ 82

Table 35: Operating Range – VAUX Power Supply ........................................................................... 83

Table 36: ADC Parameters ................................................................................................................ 83

Table 37: Recommendations for PCB Pad Surfaces ......................................................................... 88

Table 38: Solder Profile Characteristics ............................................................................................ 90

Table 39: SIM Interface – C1 Range .................................................................................................. 93

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

10 of 104

Table 40: EMC Recommendations ................................................................................................... 94

Table 41: Tray Packing ...................................................................................................................... 96

Table 42: Packing Quantities ............................................................................................................ 96

Table 43: Document Revision History ............................................................................................ 102

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

11 of 104

List of Figures

Figure 1: LE940B6 High-level Functionality ...................................................................................... 18

Figure 2: LGA Pads Layout LE940B6 334 Pads Top View .................................................................. 38

Figure 3: Power-on Circuit ................................................................................................................ 44

Figure 4: LE940B6 Initialization and Activation ................................................................................ 45

Figure 5: Power-up Flow Chart ......................................................................................................... 46

Figure 6: AT Command Managing Flow Chart .................................................................................. 47

Figure 7: Shutdown by Software Command ..................................................................................... 49

Figure 8: Hardware Shutdown .......................................................................................................... 50

Figure 9: Circuit for Unconditional Hardware Reset ........................................................................ 51

Figure 10: Circuit for Unconditional Hardware Shutdown ............................................................... 52

Figure 11: Turn Off Procedure .......................................................................................................... 53

Figure 12: Example of Linear Regulator with 5V Input ..................................................................... 58

Figure 13: Example of Switching Regulator with 12V Input – Part 1 ................................................ 59

Figure 14: Example of Switching Regulator with 12V Input – Part 2 ................................................ 59

Figure 15: ESD Protection for USB2.0 ............................................................................................... 71

Figure 16: RS232 Level Adaption Circuitry Example ......................................................................... 75

Figure 17: RS232 Serial Port Lines Connection Layout ..................................................................... 75

Figure 18: SPI Signal Connectivity ..................................................................................................... 76

Figure 19: GPIO Output Pad Equivalent Circuit ................................................................................ 81

Figure 20: Status LED circuit example .............................................................................................. 82

Figure 21: Fuel Gauge Connectivity Example ................................................................................... 84

Figure 22: Application Module Top View ......................................................................................... 86

Figure 23: PCB Pad Design ................................................................................................................ 87

Figure 24: PCB Pad Dimensions ........................................................................................................ 88

Figure 25: Inhibit Area for Micro-via ................................................................................................ 88

Figure 26: Solder Reflow Profile ....................................................................................................... 89

Figure 27: SIM Schematics ................................................................................................................ 93

Figure 28: Tray Packing ..................................................................................................................... 97

Figure 29: Tray Drawing .................................................................................................................... 98

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

12 of 104

1. Introduction

1.1. Scope

This document introduces the Telit LE940B6 module and presents possible and recommended

hardware solutions for developing a product based on the LE940B6 module. All the features and

solutions detailed in this document are applicable to all LE940B6 variants, where “LE940B6”

refers to the variants listed in the applicability table.

If a specific feature is applicable to a specific product only, it will be clearly marked.

NOTE:

LE940B6 refers to all modules listed in the Applicability Table.

This document takes into account all the basic functions of a wireless module; suggests a valid

hardware solution for each function, and points out incorrect solutions and common errors to be

avoided.

Obviously, this document cannot embrace every hardware solution or every product that can be

designed. Obviously, avoiding invalid solutions must be considered mandatory. Where the

suggested hardware configurations need not be considered mandatory, the information given

should be used as a guide and a starting point for properly developing your product with the Telit

LE940B6 module.

NOTE:

The integration of the GSM/GPRS/EGPRS/WCDMA/HSPA+/LTE LE940B6 cellular module within a

user application must be done according to the design rules described in this manual.

1.2. Audience

This document is intended for Telit customers, especially system integrators, about to implement

their applications using the Telit LE940B6 module.

1.3. Contact Information, Support

For general contact, technical support, to report documentation errors and to order manuals,

contact Telit’s Technical Support Center (TTSC) at:

• TS-EMEA@telit.com

• TS-NORTHAMERICA@telit.com

• TS-LATINAMERICA@telit.com

• TS-APAC@telit.com

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

13 of 104

Alternatively, use:

http://www.telit.com/en/products/technical-support-center/contact.php

For detailed information about where you can buy the Telit modules or for recommendations on

accessories and components, visit:

http://www.telit.com

To register for product news and announcements or for product questions contact Telit’s

Technical Support Center (TTSC).

Our aim is to make this guide as helpful as possible. Keep us informed of your comments and

suggestions for improvements.

Telit appreciates feedback from the users about the information provided.

1.4. Text Conventions

The following conventions are used to emphasize specific types of information:

Danger:

This information MUST be followed or catastrophic equipment failure or bodily injury may

occur.

Caution or Warning:

Alerts the user to important points about integrating the module. If these points are not

followed, the module and end user equipment may fail or malfunction.

NOTE:

Tip or Information – Provides advice and suggestions that may be useful when integrating the

module.

All dates are in ISO 8601 format, that is, YYYY-MM-DD.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

14 of 104

1.5. Related Documents

Table 2: Related Documents

Document Title Document Number

Ref 1: LE940B6 AT Command Reference Guide 80514ST10767A

Ref 2: LE940B6 SW User Guide 1VV0301296

Ref 3: Telit EVK2 User Guide 1vv0300704

Ref 4: SIM Integration Design Guide 80000NT10001A

1.6. Abbreviations

Table 3: Table of Abbreviations

Term Definition

ADC Analog-to-digital converter

AE Application-enabled

DAC Digital-to-analog converter

FDD Frequency division duplex

GLONASS Global orbiting navigation satellite system

GNSS Global navigation satellite system

GPIO General-purpose input/output

GPRS General packet radio services

GPS Global positioning system

GSM Global system for mobile communications

I2C Inter-integrated circuit

LTE Long term evolution

SD Secure digital

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

15 of 104

Term Definition

RGMII Reduced Gigabit media-independent interface

SIM Subscriber identity module

SOC System-on-Chip

SMX SmartMX

SPI Serial peripheral interface

UART Universal asynchronous receiver transmitter

UMTS Universal mobile telecommunications system

USB Universal serial bus

WCI Wireless Coexistence Interface

WCDMA Wideband code division multiple access

1.7. Document Organization

This document contains the following chapters:

Table 3: Document Structure

Chapter#

Chapter Title Description

1 Introduction Provides the scope of this document, target

audience, contact and support information, and text

conventions

2 General Product Description

An overview of the product features

3 LE940B6 Module

Connections

Pinout configuration and layout

4 Electrical Specifications Specifies electrical values of logic levels for this

module

5 Hardware Commands Instructs how to control the module via hardware

6 Power Supply Supply lines and current consumption

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

16 of 104

Chapter#

Chapter Title Description

7 Antenna(s) Describes the antenna connections and related

aspects of board layout design, which are most

critical for the overall product design

8 Hardware Interfaces Specifies the peripheral and audio interfaces

9 Miscellaneous Functions

10 Mounting the Module on

your Board

11 Application Guide

12 Packing System

13 Conformity Assessment

Issues

14 Safety Recommendations

15 Document History

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

17 of 104

2. General Product Description

2.1. Overview

LE940B6 is Telit’s platform for automotive telematics on-board units (OBU's) for applications,

such as automotive telematics and eCall, based on the following technologies:

• 4G cellular for voice and data communication

• GNSS (optional) - GPS, GLONASS, BeiDou, Galileo, QZSS, for positioning service

• Embedded security

• Designed for automotive markets

quality needs

In its most basic use case, LE940B6 can be applied as a wireless communication front-end for

telematics products, offering GNSS and mobile communication features to an external host CPU

through its rich interfaces.

LE940B6 can further support customer software applications and security features. LE940B6 is

based on a Yocto Linux system running on an application processor. Thanks to a dedicated

application processor and embedded security resources, product developers and manufacturers

can create products that guarantee fraud prevention and tamper evidence without extra effort

for additional security precautions.

LE940B6 can be self-sufficient and serve as a fully integrated solution for applications, such as

location-based cellular telematics, navigation, road pricing and eCall. In such a case, the customer

would simply complement the module with a power supply, speaker amplifier, microphone,

antennas, and an HMI (if applicable).

LE940B6 is offered with different regional variants according to the list in Table 1: Applicability

Table.

2.2. Applications

LE940B6 can be used for telematics applications where tamper-resistance, confidentiality,

integrity, and authenticity of end-user information are required, for example:

• Emergency call

• Telematics services

• Road pricing

• Pay-as-you-drive insurance

• Stolen vehicles tracking

• Internet connectivity

In accordance with Telit’s Robustness Validation, using AEC-Q100-defined qualification tests

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

18 of 104

2.3. General Functionality and Main Features

The LE940B6 family of automotive cellular modules features an LTE and multi-RAT modem

together with a powerful on-chip application processor and a rich set of interfaces.

The major functions and features are listed below:

• Multi-RAT with LTE carrier aggregation (Rel. 10, Cat. 6)

• Flash + DDR large enough to allow the space for customer’s own software applications

• Advanced security features

• FOTA (optional)

• Several region variants with optimal choice of RF bands in each for worldwide coverage of

countries and MNOs

• Well-designed form factor (40x40mm), accommodating the multiple RF bands in each region

variant

• Digital audio and analog audio codec

• A GNSS function is not included within the module, but can be supported with the proper

interface while mounted on the customer board

• The entire module is designed by Telit for satisfying the environment and quality

requirements of the automotive market

Figure 1 shows the high-level functionality of the LE940B6 module.

Figure 1: LE940B6 High-level Functionality

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

19 of 104

2.4. Environmental Requirements

2.4.1. Temperature Range

Operating

temperature range

-20 ~ +55°C.

This range is defined by 3GPP (the global standard for wireless

mobile communication). Telit guarantees its modules to comply with

all the 3GPP requirements and to have full functionality of the

module with in this range.

-40 ~ +85°C.

Telit guarantees full functionality within this range as well. However,

there may possibly be some performance deviations in this

extended range relative to 3GPP requirements, which means that

some RF parameters may deviate from the 3GPP specification in the

order of a few dB. For example: receiver sensitivity or maximum

output power may be slightly degraded.

Even so, all the functionalities, such as call connection, SMS, USB

communication, UART activation etc., will be maintained, and the

effect of such degradations will not lead to malfunction.

–40°C ~ +95°C.

eCall must be functional (until the module is broken)

Storage and non-

operating

temperature range

–40°C ~ +95°C

2.4.2. RoHS Compliance

As a part of the Telit corporate policy of environmental protection, the LE940B6 complies with the

RoHS (Restriction of Hazardous Substances) directive of the European Union (EU directive

2011/65/EU).

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

20 of 104

2.5. Operating Frequency Bands

The operating frequencies in WCDMA and LTE modes conform to the 3GPP specifications.

2.5.1. RF Bands per Regional Variant

Table 4 summarizes all region variants within the LE940B6 family, showing the supported band

sets in each variant and the supported band pairs for 2x carrier aggregation.

Table 4: RF Bands per Regional Variant

Band 41M for China: 2,555 - 2,655 MHz

Region

Variant

LTE FDD LTE TDD HSPA+ TD-

SCDMA

LE940B6-NA

2, 4, 5, 7, 12, 29(DL) - 2, 4, 5

- 2, 5

LTE Carrier Aggregation 2+5, 2+12, 2+29, 4+4, 4+5, 4+12, 4+29

LE940B6-NV

2, 4, 5, 7, 12, 13, 29(DL) - 2, 4, 5 - 2, 5

LTE Carrier Aggregation 2+5, 2+12, 2+13, 2+29, 4+4, 4+5, 4+12, 4+13, 4+29,

LE940B6-RW

1, 2, 3, 4, 5, 7, 8, 19, 20,

21, 26, 28, 32(DL)

- 1, 2, 3, 4, 5, 8, 19

- 2, 3, 5, 8

LTE Carrier Aggregation 1+5, 1+8, 1+19, 1+21, 1+26, 3+3, 3+5, 3+7, 3+19, 3+20,

3+26, 3+28, 4+4, 7+20, 7+28, 19+21, 20+32

LE940B6-CN

1, 3, 5, 8, 26 38, 39, 40, 41M

1, 3, 5, 8 34, 39 3, 8

LTE Carrier Aggregation 1+26, 3+3, 3+5, 3+26, 39+41, 40+40, 41+41

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

21 of 104

2.5.2. Reference Table of RF Bands Characteristics

Table 5: RF Bands Characteristics

Mode Freq. Tx (MHz) Freq. Rx (MHz)

Channels Tx-Rx Offset

PCS 1900 1850.2 ~ 1909.8

1930.2 ~ 1989.8

512 ~ 810 80 MHz

DCS 1800 1710.2 ~ 1784.8

1805.2 ~ 1879.8

512 ~ 885 95 MHz

GSM 850 824.2 ~ 848.8 869.2 ~ 893.8 128 ~ 251 45 MHz

EGSM 900 880.2 ~ 914.8 925.2 ~ 959.8 975 ~ 1023, 1 ~ 124

45 MHz

WCDMA 2100 – B1 1920 ~ 1980 2110 ~ 2170 Tx: 9612 ~ 9888

Rx: 10562 ~ 10838

190 MHz

WCDMA 1900 – B2 1850 ~ 1910 1930 ~ 1990 Tx: 9262 ~ 9538

Rx: 9662 ~ 9938

80 MHz

WCDMA 1800 – B3 1710 ~ 1785 1805 ~ 1880 Tx: 937 ~ 1288

Rx: 1162 ~ 1513

95 MHz

WCDMA AWS – B4 1710 ~ 1755 2110 ~ 2155 Tx: 1312 ~ 1513

Rx: 1537 ~ 1738

400 MHz

WCDMA 850 – B5 824 ~ 849 869 ~ 894 Tx: 4132 ~ 4233

Rx: 4357 ~ 4458

45 MHz

WCDMA 900 – B8 880 ~ 915 925 ~ 960 Tx: 2712 ~ 2863

Rx: 2937 ~ 3088

45 MHz

WCDMA 1800 –B9 1750 ~ 1784.8 1845 ~ 1879.8 Tx: 8762 ~ 8912

Rx: 9237 ~ 9387

95 MHz

WCDMA 800 – B19 830 ~ 845 875 ~ 890 Tx: 312 ~ 363

Rx: 712 ~ 763

45 MHz

TDSCDMA 2000 –

B34

2010 ~ 2025 2010 ~ 2025 Tx: 10050 ~ 10125

Rx: 10050 ~ 10125

0 MHz

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

22 of 104

Mode Freq. Tx (MHz) Freq. Rx (MHz)

Channels Tx-Rx Offset

TDSCDMA 1900 –

B39

1880 ~ 1920 1880 ~ 1920 Tx: 9400 ~ 9600

Rx: 9400 ~ 9600

0 MHz

LTE 2100 – B1 1920 ~ 1980 2110 ~ 2170 Tx: 18000 ~ 18599

Rx: 0 ~ 599

190 MHz

LTE 1900 – B2 1850 ~ 1910 1930 ~ 1990 Tx: 18600 ~ 19199

Rx: 600 ~ 1199

80 MHz

LTE 1800 – B3 1710 ~ 1785 1805 ~ 1880 Tx: 19200 ~ 19949

Rx: 1200 ~ 1949

95 MHz

LTE AWS – B4 1710 ~ 1755 2110 ~ 2155 Tx: 19950 ~ 20399

Rx: 1950 ~ 2399

400 MHz

LTE 850 – B5 824 ~ 849 869 ~ 894 Tx: 20400 ~ 20649

Rx: 2400 ~ 2649

45 MHz

LTE 2600 – B7 2500 ~ 2570 2620 ~ 2690 Tx: 20750 ~ 21449

Rx: 2750 ~ 3449

120 MHz

LTE 900 – B8 880 ~ 915 925 ~ 960 Tx: 21450 ~ 21799

Rx: 3450 ~ 3799

45 MHz

LTE 1800 – B9 1749.9 ~ 1784.9

1844.9 ~ 1879.9

Tx: 21800 ~ 2149

Rx: 3800 ~ 4149

95 MHz

LTE AWS+ – B10 1710 ~ 1770 2110 ~ 2170 Tx: 22150 ~ 22749

Rx: 4150 ~ 4749

400 MHz

LTE 700a – B12 699 ~ 716 729 ~ 746 Tx : 23010 ~ 23179

Rx : 5010 ~ 5179

30 MHz

LTE 700c – B13 777 ~ 787 746 ~ 756 Tx : 23180 ~ 23279

Rx : 5180 ~ 5279

-31 MHz

LTE 700b – B17 704 ~ 716 734 ~ 746 Tx: 23730 ~ 23849

Rx: 5730 ~ 5849

30 MHz

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

23 of 104

Mode Freq. Tx (MHz) Freq. Rx (MHz)

Channels Tx-Rx Offset

LTE 800 – B19 830 ~ 845 875 ~ 890 Tx: 24000 ~ 24149

Rx: 6000 ~ 6149

45 MHz

LTE 800 – B20 832 ~ 862 791 ~ 821 Tx: 24150 ~ 24449

Rx: 6150 ~ 6449

-41 MHz

LTE 1500 – B21 1447.9 ~ 1462.9

1495.9 ~ 1510.9

Tx: 24450 ~ 24599

Rx: 6450 ~ 6599

48 MHz

LTE 850+ – B26 814 ~ 849 859 ~ 894 Tx: 26690 ~ 27039

Rx: 8690 ~ 9039

45 MHz

LTE 700 – B28 703 ~ 748 758 ~ 803 Tx : 27210 ~ 27659

Rx : 9210 ~ 9659

45 MHz

LTE 700d – B29 Downlink only 717 ~ 728 Rx: 9660 ~ 9769 0 MHz

LTE 1500 – B32 Downlink only 1452 ~ 1496 Rx: 9920 ~ 10359 0 MHz

LTE TDD 2600 – B38

2570 ~ 2620 2570 ~ 2620 Tx: 37750 ~ 38249

Rx: 37750 ~ 38249

0 MHz

LTE TDD 1900 – B39

1880 ~ 1920 1880 ~ 1920 Tx: 38250 ~ 38649

Rx: 38250 ~ 38649

0 MHz

LTE TDD 2300 – B40

2300 ~ 2400 2300 ~ 2400 Tx: 38650 ~ 39649

Rx: 38650 ~ 39649

0 MHz

LTE TDD 2500 – B41

2496 ~ 2690 2496 ~ 2690 Tx: 39650 ~ 41589

Rx: 39650 ~ 41589

0 MHz

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

24 of 104

2.6. Sensitivity

LE940B6 maximum sensitivity levels are as follows (exact performance figures will be specified at

a later stage):

• < 3GPP @ 2G

• < 3GPP @ 3G

• < 3GPP @ 4G FDD (BW=5 MHz)

• < 3GPP @ 4G TDD (BW=5 MHz)

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

25 of 104

2.7. LE940B6 Mechanical Specifications

2.7.1. Dimensions

The LE940B6 module’s overall dimensions are:

• Length: 40 mm, +/- 0.20 mm tolerance

• Width: 40 mm, +/- 0.20 mm tolerance

• Thickness: 3.0 mm, +/- 0.15 mm tolerance (with label)

2.7.2. Weight

The nominal weight of the LE940B6 module is 11 gram.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

26 of 104

3. LE940B6 Module Connections

3.1. Pin-out

Table 6: LE940B6 Pin-out

PAD Signal I/O

Function Type COMMENT

USB HS 2.0 Communication Port

A18 USB_VBUS AI

Power sense for the internal USB

transceiver

D19 USB_D+ I/O

USB differential Data (+)

F19 USB_D- I/O

USB differential Data (-)

Asynchronous UART

AH19 C103/TXD I Serial data input (TXD) from DTE 1.8V

AF19 C104/RXD O Serial data output (RXD) to DTE 1.8V

AA18 C105/RTS I

Input for Request To Send signal

(RTS) from DTE 1.8V

AK19 C106/CTS O

Output for Clear To Send signal

(CTS) to DTE 1.8V

AG18 C107/DSR O

Output for Data Set Ready signal

(DSR) to DTE 1.8V

AC18 C108/DTR I

Input for Data Terminal Ready

signal (DTR) from DTE 1.8V

AE18 C109/DCD O

Output for

Data Carrier Detect

signal (DCD) to DTE 1.8V

AJ18 C125/RING O

Output for Ring Indicator signal (RI)

to DTE 1.8V

Asynchronous Auxiliary UART

AB19 TXD_AUX O Auxiliary UART (Tx Data to DTE) 1.8V

AD19 RXD_AUX I Auxiliary UART (Rx Data from DTE) 1.8V

Asynchronous UART3

AM9 UART3_TXD I Serial data input (TXD) from DTE 1.8V

AM11

UART3_RXD O Serial data output (RXD) to DTE 1.8V

AM13

UART3_RTS I

Input for Request To Send (RTS)

from DTE 1.8V

AM15

UART3_CTS O

Output for Clear To Send (CTS) to

DTE 1.8V

JTAG – Joint Test Action Group

E4 JTAG_TDI I JTAG_TDI 1.8V

F3 JTAG_RESOUT_N

O JTAG_RESOUT* 1.8V

F5 JTAG_TRIGOUT - JTAG_TRIGOUT 1.8V

G2 JTAG_RTCK O JTAG_RTCK 1.8V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

27 of 104

H3 JTAG_TCK I JTAG_TCK 1.8V

J2 JTAG_TRST_N I JTAG_TRST* 1.8V

K3 JTAG_TDO O JTAG_TDO 1.8V

L2 JTAG_TMS I JTAG_TMS 1.8V

M3 JTAG_TRIGIN - JTAG_TRIGIN 1.8V

JTAG - MiPi 34 Interface

L4 JTAG_PTI_CLK O MiPi Clock 1.8V

N4 JTAG_PTI_DATA0

I/O

MiPi Data 0 1.8V

R4 JTAG_PTI_DATA1

I/O

MiPi Data 1 1.8V

T4 JTAG_PTI_DATA2

I/O

MiPi Data 2 1.8V

V4 JTAG_PTI_DATA3

I/O

MiPi Data 3 1.8V

SIM Card Interface

A8 SIMVCC1 -

External SIM signal

–

Power supply

for the SIM 1.8/2.9V

A10 SIMCLK1 O External SIM signal – Clock 1.8/2.9V

B7 SIMIN1 I External SIM signal – Presence 1.8V Active Low

B9 SIMIO1 I/O

External SIM signal – Data I/O 1.8/2.9V

B11 SIMRST1 O External SIM signal – Reset 1.8/2.9V

SIM Card Interface 2

D15 SIMVCC2 -

External SIM signal

–

Power supply

for the SIM 1.8/2.9V

C16 SIMCLK2 O External SIM signal – Clock 1.8/2.9V

C18 SIMIN2 I

External SIM signal

–

Presence

(active low) 1.8V Active Low

E16 SIMIO2 I/O

External SIM signal – Data I/O 1.8/2.9V

D17 SIMRST2 O External SIM signal – Reset 1.8/2.9V

Analog Audio Interface

B5 EAR1_MT+ AO

Earphone signal output, phase +

A4 EAR1_MT- AO

Earphone signal output, phase -

B3 MIC1_MT+ AI

Microphone input, phase +

A2 MIC1_MT- AI

Microphone input, phase -

G6 MIC_BIAS AO

Microphone Bias Power

Digital Voice Interface (DVI)

C8 DVI_RX I Digital Voice interface (Rx) 1.8V

C10 DVI_CLK O

Digital Voice interface (CLK master

output) 1.8V

D9 DVI_TX O Digital Voice interface (Tx) 1.8V

D11 DVI_WA0 O

Digital Voice interface (WA0 master

output) 1.8V

SPI – Serial Peripheral Interface

K19 SPI_MOSI O SPI data Master output Slave input 1.8V

M19 SPI_MISO I SPI data Master input Slave output 1.8V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

28 of 104

N18 SPI_CS O SPI Chip select output 1.8V

P19 SPI_CLK O SPI Clock output 1.8V

I2C Interface

C14 I2C_SCL I/O

I2C Clock 1.8V

D13 I2C_SDA I/O

I2C Data 1.8V

Digital I/O

F9 GPIO_01 I/O

GPIO_01 1.8V

E10 GPIO_02 I/O

GPIO_02 1.8V

F11 GPIO_03 I/O

GPIO_03 1.8V

E12 GPIO_04 I/O

GPIO_04 1.8V

F13 GPIO_05 I/O

GPIO_05 1.8V

E14 GPIO_06 I/O

GPIO_06 1.8V

R18 GPIO_07 I/O

GPIO_07 1.8V

S19 GPIO_08 I/O

GPIO_08 1.8V

U19 GPIO_09 I/O

GPIO_09 1.8V

W19 GPIO_10 I/O

GPIO_10 1.8V

L18 GPIO_11 I/O

GPIO_11 1.8V

J18 GPIO_12 I/O

GPIO_12 1.8V

AN4 GPIO_20 I/O

GPIO_20 1.8V

H1 GPIO_21 I/O

GPIO_21 1.8V

K1 GPIO_22 I/O

GPIO_22 1.8V

Analog to Digital Converter

D5 ADC_IN1 AI

Analog to Digital Converter Input 1 Analog

E6 ADC_IN2 AI

Analog to Digital Converter Input 2 Analog

F7 ADC_IN3 AI

Analog to Digital Converter Input 3 Analog

Ethernet MAC/PHY Signals

G14 MAC_MDC O Management Data Clock 2.5/3.3V

G12 MAC_MDIO I/O

Management Data I/O 2.5/3.3V

V16 MAC_TXD[0] O RGMII or RMII TXD[0] 2.5/3.3V

T16 MAC_TXD[1] O RGMII or RMII TXD[1] 2.5/3.3V

R16 MAC_TXD[2] O RGMII TXD[2] 2.5/3.3V

N16 MAC_TXD[3] O RGMII TXD[3] 2.5/3.3V

L16 MAC_GTX_CLK O RGMII Transmit Clock 2.5/3.3V

G16 MAC_TXEN_ER O

RGMII Transmit Enable / Error or

RMII Transmit Enable 2.5/3.3V

AL16 MAC_RXD[0] I RGMII or RMII RXD[0] 2.5/3.3V

AJ16 MAC_RXD[1] I RGMII or RMII RXD[1] 2.5/3.3V

AG16 MAC_RXD[2] I RGMII RXD[2] 2.5/3.3V

AE16 MAC_RXD[3] I RGMII RXD[3] 2.5/3.3V

AC16 MAC_RX_CLK I RGMII Receive Clock 2.5/3.3V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

29 of 104

X16 MAC_RXDV_ER I

RGMII Receive Data Available/Error

or RMII Receive Error 2.5/3.3V

G10 ETH_INT_N I Ethernet PHY Interrupt 2.5/3.3V

G8 ETH_RST_N O Ethernet PHY Reset Output 2.5/3.3V

RF Section

AD1 ANT_1 I/O

Primary Antenna 1 RF

AU9 ANT_DIV_1 I Diversity Antenna 1 RF

S1 ANT_GPS I GPS Antenna RF

Miscellaneous Functions

F17 VRTC AI

VRTC Backup capacitor -

K17 VIO_1.8V O VIO_1.8V for reference voltage 1.8V

AN8 RESET_N I Reset Input Active low

AN10 SW_RDY O

Indicates that the boot sequence

completed successfully 1.8V

AN12 SHDN_N I Unconditional Shutdown Input Active low

AS1 ON_OFF_N I Power ON/OFF Input Active low

AU3 STAT_LED O Status Indicator LED 1.8V

P17 VAUX/PWRMON

Supply output for external

accessories / Power ON Monitor 1.8V

H17 VPP I Vpp for eFuse

Power Supply

AP17 VBATT - Main Power Supply (Digital Section)

Power

AP19 VBATT - Main Power Supply (Digital Section)

Power

AR18 VBATT - Main Power Supply (Digital Section)

Power

AR20 VBATT - Main Power Supply (Digital Section)

Power

AS17 VBATT_PA -

Main Power Supply (RF Transmit

Power Section) Power

AS19 VBATT_PA -

in Power Supply (RF Transmit

Power Section) Power

AT18 VBATT_PA -

Main Power Supply (RF Transmit

Power Section) Power

AU17 VBATT_PA -

Main Power Supply (RF Transmit

Power Section) Power

AU19 VBATT_PA -

Main Power Supply (RF Transmit

Power Section) Power

AT20 VBATT_PA -

Main Power Supply (RF Transmit

Power Section) Power

Ground

A6 GND - Ground Ground

A12 GND - Ground Ground

B13 GND - Ground Ground

B15 GND - Ground Ground

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

30 of 104

B17 GND - Ground Ground

C4 GND - Ground Ground

C6 GND - Ground Ground

D3 GND - Ground Ground

D7 GND - Ground Ground

E18 GND - Ground Ground

F1 GND - Ground Ground

G18 GND - Ground Ground

H19 GND - Ground Ground

M1 GND - Ground Ground

N2 GND - Ground Ground

P1 GND - Ground Ground

P3 GND - Ground Ground

R2 GND - Ground Ground

T2 GND - Ground Ground

T18 GND - Ground Ground

U1 GND - Ground Ground

V18 GND - Ground Ground

W1 GND - Ground Ground

X2 GND - Ground Ground

X18 GND - Ground Ground

Y1 GND - Ground Ground

Y19 GND - Ground Ground

AA2 GND - Ground Ground

AB1 GND - Ground Ground

AC2 GND - Ground Ground

AE2 GND - Ground Ground

AF1 GND - Ground Ground

AG2 GND - Ground Ground

AH1 GND - Ground Ground

AJ2 GND - Ground Ground

AK1 GND - Ground Ground

AK17 GND - Ground Ground

AL18 GND - Ground Ground

AM17

GND - Ground Ground

AM19

GND - Ground Ground

AN16 GND - Ground Ground

AN18 GND - Ground Ground

AP3 GND - Ground Ground

AP5 GND - Ground Ground

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

31 of 104

AP7 GND - Ground Ground

AP9 GND - Ground Ground

AP11 GND - Ground Ground

AP13 GND - Ground Ground

AP15 GND - Ground Ground

AR2 GND - Ground Ground

AR4 GND - Ground Ground

AR6 GND - Ground Ground

AR8 GND - Ground Ground

AR10 GND - Ground Ground

AR12 GND - Ground Ground

AR14 GND - Ground Ground

AR16 GND - Ground Ground

AS5 GND - Ground Ground

AS7 GND - Ground Ground

AS9 GND - Ground Ground

AS11 GND - Ground Ground

AS13 GND - Ground Ground

AS15 GND - Ground Ground

AT4 GND - Ground Ground

AT6 GND - Ground Ground

AT8 GND - Ground Ground

AT10 GND - Ground Ground

AT12 GND - Ground Ground

AT14 GND - Ground Ground

AT16 GND - Ground Ground

AU1 GND - Ground Ground

AU5 GND - Ground Ground

AU7 GND - Ground Ground

AU11 GND - Ground Ground

AU15 GND - Ground Ground

AL2 GND - Ground Ground

AN2 GND - Ground Ground

L20 GND - Ground Ground

N20 GND - Ground Ground

ZZ19 GND - Ground Ground

A20 GND - Ground Ground

AV20 GND - Ground Ground

ZZ1 GND - Ground Ground

A0 GND - Ground Ground

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

32 of 104

AV0 GND - Ground Ground

N0 GND - Ground Ground

R0 GND - Ground Ground

T0 GND - Ground Ground

V0 GND - Ground Ground

X0 GND - Ground Ground

AA0 GND - Ground Ground

AC0 GND - Ground Ground

AE0 GND - Ground Ground

AG0 GND - Ground Ground

AJ0 GND - Ground Ground

AL0 GND - Ground Ground

AN0 GND - Ground Ground

AR0 GND - Ground Ground

AV8 GND - Ground Ground

AV10 GND - Ground Ground

AV12 GND - Ground Ground

AV14 GND - Ground Ground

AV16 GND - Ground Ground

AV18 GND - Ground Ground

T8 GND - Ground Ground

V8 GND - Ground Ground

X8 GND - Ground Ground

AA8 GND - Ground Ground

U9 GND - Ground Ground

W9 GND - Ground Ground

Y9 GND - Ground Ground

T10 GND - Ground Ground

V10 GND - Ground Ground

X10 GND - Ground Ground

AA10 GND - Ground Ground

U11 GND - Ground Ground

W11 GND - Ground Ground

Y11 GND - Ground Ground

T12 GND - Ground Ground

V12 GND - Ground Ground

X12 GND - Ground Ground

AA12 GND - Ground Ground

ZZ101

GND - Ground Ground

B101 GND - Ground Ground

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

33 of 104

D101 GND - Ground Ground

U101 GND - Ground Ground

W101

GND - Ground Ground

Y101 GND - Ground Ground

AR101

GND - Ground Ground

AT101

GND - Ground Ground

AV101

GND - Ground Ground

ZZ102

GND - Ground Ground

B102 GND - Ground Ground

D102 GND - Ground Ground

U102 GND - Ground Ground

W102

GND - Ground Ground

Y102 GND - Ground Ground

AR102

GND - Ground Ground

AT102

GND - Ground Ground

AV102

GND - Ground Ground

Reserved

B19 Reserved - Reserved

C20 Reserved - Reserved

E20 Reserved - Reserved

G20 Reserved - Reserved

J20 Reserved - Reserved

AN14 Reserved - Reserved

E8 Reserved - Reserved

E2 Reserved - Reserved

D1 Reserved - Reserved

C2 Reserved - Reserved

B1 Reserved - Reserved

C12 Reserved - Reserved

J4 Reserved - Reserved

G4 Reserved - Reserved

AE4 Reserved - Reserved

AC4 Reserved - Reserved

Y3 Reserved - Reserved

AB3 Reserved - Reserved

AD3 Reserved - Reserved

AF3 Reserved - Reserved

AH3 Reserved - Reserved

AK3 Reserved - Reserved

AM3 Reserved - Reserved

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

34 of 104

AG4 Reserved - Reserved

AJ4 Reserved - Reserved

AL4 Reserved - Reserved

AM5 Reserved - Reserved

X4 Reserved - Reserved

AA4 Reserved - Reserved

S17 Reserved - Reserved

U17 Reserved - Reserved

AH17 Reserved - Reserved

Y17 Reserved - Reserved

AF17 Reserved - Reserved

AB17 Reserved - Reserved

W17 Reserved - Reserved

AD17 Reserved - Reserved

R20 Reserved - Reserved

T20 Reserved - Reserved

V20 Reserved - Reserved

X20 Reserved - Reserved

AA20 Reserved - Reserved

AC20 Reserved - Reserved

AE20 Reserved - Reserved

AG20 Reserved - Reserved

AJ20 Reserved - Reserved

AA16 Reserved - Reserved

J16 Reserved - Reserved

ZZ11 Reserved - Reserved

ZZ13 Reserved - Reserved

ZZ15 Reserved - Reserved

ZZ17 Reserved - Reserved

ZZ9 Reserved - Reserved

ZZ7 Reserved - Reserved

ZZ5 Reserved - Reserved

ZZ3 Reserved - Reserved

C0 Reserved - Reserved

E0 Reserved - Reserved

G0 Reserved - Reserved

J0 Reserved - Reserved

AM1 Reserved - Reserved

AU13 Reserved - Reserved

V2 Reserved - Reserved

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

35 of 104

W3 Reserved - Reserved

A14 Reserved - Reserved

A16 Reserved - Reserved

F15 Reserved - Reserved

AP1 Reserved - Reserved

M17 Reserved - Reserved

AN6 Reserved - Reserved

AS3 Reserved - Reserved

AT2 Reserved - Reserved

S3 Reserved - Reserved

U3 Reserved - Reserved

L0 Reserved - Reserved

AM7 Reserved - Reserved

AL20 Reserved - Reserved

AN20 Reserved - Reserved

AT0 Reserved - Reserved

AV6 Reserved - Reserved

AV2 Reserved - Reserved

AV4 Reserved - Reserved

NOTE:

When the UART signals are used as the communication port between the host and the

modem:

• The DTR pin must be connected to enter LE940B6 power saving mode.

• The RI pin must be connected to wake up the host when a call is coming while the host

is in Sleep mode.

• The RTS must be connected to GND (on the module side) if flow control is not used.

If the UART port is not used, all UART signals can be left disconnected.

NOTE:

Unless otherwise specified, RESERVED pins must be left unconnected (floating).

The only exceptions are in the following Section: 3.2 LE940B6 Signals That Must Be Connected.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

36 of 104

3.2. LE940B6 Signals That Must Be Connected

Table 7 lists the LE940B6 signals that must be connected even if not used by the end application:

Table 7: Mandatory Signals

PAD Signal Notes

AP17, AP19, AR18, AR20, AS17, AS19, AT18,

AU17, AU19, AT20

VBATT &

VBATT_PA

A6, A12, B13, B15, B17, C4, C6, D3, D7, E18,

F1, G18, H19, M1, N2, P1, P3, R2, T2, T18, U1,

V18, W1, X2, X18, Y1, Y19, AA2, AB1, AC2, AE2,

AF1, AG2, AH1, AJ2, AK1, AK17, AL18, AM17,

AM19, AN16, AN18, AP3, AP5, AP7, AP9, AP11,

AP13, AP15, AR2, AR4, AR6, AR8, AR10, AR12,

AR14, AR16, AS5, AS7, AS9, AS11, AS13, AS15,

AT4, AT6, AT8, AT10, AT12, AT14, AT16, AU1,

AU5, AU7, AU11, AU15, AL2, AN2, L20, N20,

ZZ19, A20, AV20, ZZ1, A0, AV0, N0, R0, T0, V0,

X0, AA0, AC0, AE0, AG0, AJ0, AL0, AN0, AR0,

AV8, AV10, AV12, AV14, AV16, AV18, T8, V8,

X8, AA8, U9, W9, Y9, T10 ,V10, X10, AA10,

U11, W11, Y11, T12, V12, X12, AA12

GND

AS1 ON/OFF*

AN12 SHDN_N

D19 USB_D+ If not used, connect to a test

point or a USB connector

F19 USB_D- If not used, connect to a test

point or a USB connector

A18 USB_VBUS If not used, connect to a test

point or a USB connector

C20 USB_SS_RX_P

If not used, connect to a test

point or a USB connector

E20 USB_SS_RX_M

If not used, connect to a test

point or a USB connector

G20 USB_SS_TX_P

If not used, connect to a test

point or a USB connector

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

37 of 104

J20 USB_SS_TX_M

If not used, connect to a test

point or a USB connector

AH19 C103/TXD If not used, connect to a test

point

AF19 C104/RXD If not used, connect to a test

point

AA18 C105/RTS If flow control is not used,

connect to GND

AK19 C106/CTS If not used, connect to a test

point

AB19 TXD_AUX If not used, connect to a test

point

AD19 RXD_AUX If not used, connect to a test

point

AD1 ANT_1 If not used, connect to a 50 Ohm

termination

AU9 ANT_DIV_1 If not used, connect to a 50 Ohm

termination

S1 ANT_GPS If not used, connect to a 50 Ohm

termination

E4, F3, F5, G2, H3, J2, K3, L2, M3, L4, N4, R4,

T4, V4 For Analysis

Recommended to connect to

test

points for analysis

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

38 of 104

3.3. LGA Pads Layout

Figure 2: LGA Pads Layout LE940B6 334 Pads Top View

(*) MMC is not supported, and the pins assigned for it became Reserved

NOTE:

The pin defined as RFU must be considered RESERVED and not connected to any pin in the

application. The related area on the application must be kept empty.

ZZ A B C D E F G H J K L M N P R S T U V W X Y AA AB AC AD AE AF AG AH AJ AK AL AM AN AP AR AS AT AU AV

101

GND GND GN D GND GND GND GND GND GN D

101

GND RFU RFU RFU RFU RFU GND GND GND GND GND GND GND GND GND GND GND GND GND RFU GND

GND RFU RFU GND GPIO_2

GPIO_2

2GND GND ANT_GP

SGND GND GND GND ANT_1 GND GND GND RFU RFU ON_OFF

_N GND

MIC1_M

T- RFU RFU JTAG_R

TCK

JTAG_T

RST_N

JTAG_T

MS GND GND GND RFU GND GND GND GND GND GND GND GND GND RFU RFU

RFU MIC1_M

T+ GND

JTAG_R

ESOUT_

JTAG_T

RIGIN GND RFU RFU RFU RFU RFU RFU RFU RFU RFU RFU GND RFU ST AT_L

EAR1_M

T- GND JTAG_T

DI RFU RFU JTAG_P

TI_CLK

JTAG_P

TI_DAT

JTAG_P

TI_DAT

JTAG_P

TI_DAT

JTAG_P

TI_DAT

RFU RFU RFU RFU RFU RFU RFU GPIO_2

0GND GND RFU

RFU EAR1_M

T+

ADC_IN

JTAG_T

RIGOUT RFU GND GND GND

GND GND ADC_IN

MIC_BIA

SRFU GND GND RFU

RFU SIMIN1 GND ADC_IN

3RFU GND GND GND

SIMVCC

1DVI_RX RFU ETH_RS

T_N GND GND GND GND RESET_

NGND GND GND

RFU SIMIO1 DVI_TX GPIO_0

1GND GND GND UART3_

TXD GND GND ANT_DI

V_1

SIMCLK

DVI_CL

GPIO_0

ETH_IN

T_N GND GND GND GND SW_RDY GND GND GND

RFU SIMRST

DVI_WA

GPIO_0

3GND GND GND UART3_

RXD GND GND GND

GND RFU GPIO_0

MAC_MD

IO GND GND GND GND SHDN_N GND GND GND

RFU GND I2C_SDA GPIO_0

UART3_

RTS GND GND RFU

RFU I2C_SCL GPIO_0

MAC_MD

CRFU GND GND GND

RFU GND SIMVCC

2RFU UART3_

CTS GND GND GND

RFU SIMCLK

2SIMIO2 MAC_TX

EN_ER RFU MAC_GT

X_CLK

MAC_TX

D[3]

MAC_TX

D[2]

MAC_TX

D[1]

MAC_TX

D[0]

MAC_RX

DV_ER RFU MAC_RX

_CLK

MAC_RX

D[3]

MAC_RX

D[2]

MAC_RX

D[1]

MAC_RX

D[0] GND GND GND GND

RFU GND SIMRST

2VRTC VPP VIO _1.8

VRFU VAUX/P

WRMON RFU RFU RFU RFU RFU RFU RFU RFU GND GND VBATT VBATT_

VBATT_

USB_VB

US SIMIN2 GND GND GPIO_1

GPIO_1

1SPI_CS GP IO_0

7GND GND GND C105/RT

C108/DT

C109/DC

C107/DS

C125/RI

NG GND GND VBATT VBATT_

PA GND

GND RFU USB_D+ USB_D- GND SPI _MO

SPI_ MIS

SPI_CL

GPIO_0

GPIO_1

0GND TXD_AU

RXD_AU

C104/RX

C103/TX

C106/CT

SGND VBATT VBATT_

VBATT_

GND RFU RFU RFU RFU GND GND RFU RFU RFU RFU RFU RFU RFU RFU RFU RFU RFU VBATT VBATT_

PA GND

102

GND GND GN D GND GND GND GND GND GN D

102

ZZ A B C D E F G H J K L M N P R S T U V W X Y AA AB AC AD AE AF AG AH AJ AK AL AM AN AP AR AS AT AU AV

LE940B6 (40 mm X 40 mm) Form Factor Pin MAP

TOP VIEW

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

39 of 104

4. Electrical Specifications

4.1. Absolute Maximum Ratings – Not Operational

Caution:

A deviation from the value ranges listed below may harm the LE940B6 module.

Table 8: Absolute Maximum Ratings – Not Operational

Symbol Parameter Min Max Unit

VBATT Battery supply voltage on pin VBATT -0.3 +6.0 [V]

VBATT_PA Battery supply voltage on pin VBATT_PA -0.3 +6.0 [V]

4.2. Recommended Operating Conditions

Table 9: Recommended Operating Conditions

Symbol Parameter Min Typ Max Unit

amb

Ambient temperature -40 +25 +85 [°C]

VBATT Battery supply voltage on pin

VBATT

3.4 3.8 4.2 [V]

VBATT_PA Battery supply voltage on pin

VBATT_PA

3.4 3.8 4.2 [V]

BATT_PA +

BATT

Peak current to be used to

dimension decoupling

capacitors on pin VBATT_PA

- 80 2000 [mA]

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

40 of 104

4.3. Logic Level Specifications

Unless otherwise specified, all the interface circuits of the LE940B6 are 1.8V CMOS logic.

Only few specific interfaces (such as MAC, USIM and SD Card) are capable of dual voltage I/O.

The following tables show the logic level specifications used in the LE940B6 interface circuits. The

data specified in the tables below is valid throughout all drive strengths and the entire

temperature ranges.

NOTE:

Do not connect LE940B6 digital logic signals directly to OEM digital logic signals with a level

higher than 2.7V for 1.8V CMOS signals.

4.3.1. 1.8V Standard GPIOs

Table 10: Absolute Maximum Ratings – Not Functional

Parameter Min Max

Input level on standard GPIOs when on

-0.3V +2.3V

Table 11: Operating Range – Interface Levels (1.8V CMOS)

Parameter Min Max

Input high level 1.26V 2.0V

Input low level -0.2V 0.36V

Output high level 1.6V ---

Output low level --- 0.2V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

41 of 104

4.3.2. 1.8V I2C Pads

Table 12: Operating Range – 1.8V I2C Pads

Parameter Min Max

Input high level 1.26V 2.3V

Input low level -0.3V 0.54V

Output high level --- ---

Output low level --- 0.36V

4.3.3. 1.2V EMIC Pads

Table 13: Operating Range – 1.2V EMIC Pads

Parameter Min Max

Input high level 0.84V 1.4V

Input low level -0.2V 0.24V

Output high level 1.0V ---

Output low level --- 0.2V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

42 of 104

4.3.4. 1.8V/2.9V SIM Pads

Table 14: Operating Range – 1.8V SIM Pads

Parameter Min Max

Input high level 1.26V 2.1V

Input low level -0.3V 0.36V

Output high level 1.26V 2.1V

Output low level -0.3V 0.36V

Table 15: Operating Range – 2.9V SIM Pads

Parameter Min Max

Input high level 2.03V 3.1V

Input low level -0.3V 0.58V

Output high level 2.03V 3.1V

Output low level -0.3V 0.58V

4.3.5. USB

Table 16: Operating Range – USB_D+, USB_D- Pads

Parameter Min Max

Input high level 2.0V ---

Input low level --- 0.8V

Output high level 2.8V ---

Output low level --- 0.3V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

43 of 104

4.3.6. 2.5V/3.3V EMAC Interface for RMII and RGMII

Table 17: Absolute Maximum Ratings – 3.3V EMAC Interface

Parameter Min Max

Input level on 3.3V EMAC when on -0.3V 3.6V

Table 18: Operating Range – 2.5V EMAC Interface

Parameter Min Max

Input high level 1.7V 2.5V

Input low level -0.3V 0.7V

Output high level 2V ---

Output low level --- 0.4V

Table 19: Operating Range – 3.3V EMAC Interface

Parameter Min Max

Input high level 2V 3.3V

Input low level -0.3V 0.8V

Output high level 2.6V ---

Output low level --- 0.5V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

44 of 104

5. Hardware Commands

5.1. Turning on the LE940B6 Module

To turn on the LE940B6 module, the ON_OFF_N pad must be asserted low in the range of 80 - 120

milliseconds and then released.

Figure 3 illustrates a simple circuit to power on the module using an inverted buffer output.

Figure 3: Power-on Circuit

GND

Power ON Impulse

80ms < Hold Time < 120ms

ON_OFF_N

NOTE:

In case VBATT need to be removed and applied again. The application must take into account the

decay time of the power supply after removal of VBATT. VBATT input must be at zero volt prior

to the reapplication of VBATT."

5.2. Initialization and Activation State

After turning on the LE940B6 module, a predefined internal boot sequence performs the HW and

SW initialization of the module, which takes some time to fully complete. During this process, the

LE940B6 is not accessible.

As shown in Figure 4, the LE940B6 becomes operational at least 25 seconds after PWRMON goes

HIGH.

NOTE:

During the Initialization state, AT commands are not available. The DTE host must wait for the

Activation state prior to communicating with the LE940B6.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

45 of 104

Figure 4: LE940B6 Initialization and Activation

NOTE:

To check whether the LE940B6 has completely powered on, monitor the SW_RDY hardware line.

When SW_RDY goes high, the module has completely powered on and is ready to accept AT

commands.

NOTE:

Do not use any pull-up resistor on the ON_OFF_N line as it is internally pulled up. Using a pull-up

resistor may cause latch-up problems on the LE940B6 power regulator and improper powering

on/off of the module. The ON_OFF_N line must be connected only in an open-collector

configuration.

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

46 of 104

Figure 5 shows a flow chart for the proper power-up procedure:

Figure 5: Power-up Flow Chart

Modem ON Procedure

START

VBATT > 3.4V ?

VAUX/PWRMON = ON?

ON_OFF_N = LOW

80 ms < Hold Time < 120 ms

ON_OFF_N = HIGH

VAUX/PWRMON = ON?

Delay = 25 sec

Go to

Start AT CMD

Modem ON Procedure

END

Go to

HW SHUTDOWN

Unconditional

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

47 of 104

Figure 6 shows a flow chart illustrating the AT commands managing procedure.

Figure 6: AT Command Managing Flow Chart

Start AT CMD

START

Delay 300 ms

Enter AT <CR>

AT Answer in

1 sec ?

Start AT CMD

END

Go to

Modem ON Procedure

Go to

HW SHUTDOWN

Undonditional

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

48 of 104

5.3. Turning off the LE940B6 Module

Turning off the device can be done in four different ways:

• Shutdown by software command using AT#SHDN command

• Hardware shutdown using ON_OFF_N pad

• Hardware Unconditional Reset using the RESET_N pad

• Hardware Unconditional Shutdown using the SHDN_N pad

When the device is shut down by a software command or a hardware shutdown, it issues a

detach request to the network, informing the network that the device will not be reachable any

more.

NOTE:

To check if the device has powered off, monitor the VAUX/PWRMON hardware line. When

VAUX/PWRMON goes low, this indicates that the device has powered off.

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

NOTE:

VBATT must be never removed before the proper OFF procedure is performed.

NOTE:

In case VBATT need to be removed and applied again. The application must take into account the

decay time of the power supply after removal of VBATT. VBATT input must be at zero volt prior

to the reapplication of VBATT.”

5.3.1. Shutdown by Software Command

The LE940B6 module can be shut down by a software command.

When a shutdown command is sent, LE940B6 goes into the Finalization state and at the end of

the finalization process shuts down VAUX/PWRMON.

The duration of the Finalization state can differ according to the current situation of the module,

so a value cannot be defined.

Usually, it will take more than 6 seconds from sending a shutdown command until reaching a

complete shutdown. The DTE host should monitor the status of VAUX/PWRMON to observe the

actual power-off.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

49 of 104

Figure 7: Shutdown by Software Command

Finalization State OFF State

Internal State

VAUX/PWRMON

VBATT

Activation State

AT#SHDN

Variable Above

6 sec

Monitoring Status

NOTE:

To check whether the device has powered off, monitor the VAUX/PWRMON hardware line.

When VAUX/PWRMON goes low, the device has powered off.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

50 of 104

5.3.2. Hardware Shutdown

To turn off the LE940B6 module, the ON_OFF_N pad must be asserted low in the range of 1150 -

1250 milliseconds and then released. Use the same circuitry and timing for power-on.

When the ON_OFF_N is asserted low for a period in the range 1150 - 1250 milliseconds and then

released, LE940B6 goes into the Finalization state and in the end shuts down VAUX/PWRMON.

The duration of the Finalization state can differ according to the current situation of the module,

so a value cannot be defined.

Usually, it will take more than 6 seconds from sending a shutdown command until reaching a

complete shutdown. The DTE host should monitor the status of VAUX/PWRMON to observe the

actual power-off.

Figure 8: Hardware Shutdown

OFF State

Internal State

VAUX/PWRMON

VBATT

Activation State

Variable Above

6 sec

Monitoring Status

ON_OFF_N

1150ms < Hold Time < 1250ms

Finalization State

NOTE:

To check whether the device has powered off, monitor the VAUX/PWRMON hardware line.

When VAUX/PWRMON goes low, the device has powered off.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

51 of 104

5.3.3. Unconditional Hardware Reset (RESET_N)

To unconditionally restart the LE940B6 module, the RESET_N pad must be tied low in the range

1300 - 1800 milliseconds and then released.

Figure 9 shows a simple circuit for this action.

Figure 9: Circuit for Unconditional Hardware Reset

GND

Unconditional

Reset Impulse

1300ms < Hold Time < 1800ms

RESET_N

NOTE:

The Unconditional Hardware Reset must always be implemented on the boards, but the software

must use it only as an emergency exit procedure, and not as a normal power-off operation.

NOTE:

Do not use any pull-up resistor on the RESET_N line or any totem pole digital output. Using a pull-

up resistor may cause latch-up problems on the LE940B6 power regulator and improper

functioning of the module. The RESET_N line must be connected only in an open-collector

configuration.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

52 of 104

5.3.4. Unconditional Hardware Shutdown

To unconditionally shut down the LE940B6 module, the SHDN_N pad must be tied low for at least

200 milliseconds and then released.

Figure 10 shows a simple circuit for applying an unconditional shutdown.

Figure 10: Circuit for Unconditional Hardware Shutdown

GND

Unconditional

Shutdown Impulse

At least 200ms

SHDN_N

To check whether the device has powered off, monitor the VAUX/PWRMON hardware line. When

VAUX/PWRMON goes low, the device has powered off.

NOTE:

Do not use any pull-up resistor on the SHDN_N line or any totem pole digital output. Using a pull-

up resistor may cause latch-up problems on the LE940B6 power regulator and improper

functioning of the module. The SHDN_N line must be connected only in an open-collector

configuration.

NOTE:

The Unconditional Hardware Shutdown (SHDN_N) must always be implemented on the boards,

but the software must use it only as an emergency exit procedure, and not as a normal power-off

operation.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

53 of 104

Figure 11 shows a flow chart of the proper turn off procedure.

Figure 11: Turn Off Procedure

Modem OFF Procedure

START

VAUX/PWRMON = ON?

OFF Mode

ON_OFF_N = LOW

Delay = 200 ms

ON_OFF_N = HIGH

AT#SHDN

VAUX/PWRMON = ON?

Looping for more

6 sec

Modem OFF Procedure

END

Go to

Start AT CMD

HW SHUTDOWNSW SHUTDOWN

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

54 of 104

6. Power Supply

The power supply circuitry and board layout are very important parts of the full product design,

with critical impact on the overall product performance. Read the following requirements and

guidelines carefully to ensure a good and proper design.

6.1. Power Supply Requirements

The LE940B6 power requirements are as follows:

Table 20: Power Supply Requirements

Nominal supply voltage 3.8V

Supply voltage range 3.4V – 4.2V

Max ripple on module input supply 30 mV

Table 21 provides typical current consumption values of LE940B6 for the various available modes.

Table 21: LE940B6 Current Consumption

Mode Average (Typ.)

Mode Description

Switched Off

Switched off 0.1 mA Module supplied but switched Off

Idle Mode (Standby Mode; No Call in Progress)

AT+CFUN=4 2.5 mA Tx and Rx disabled ; module is not registered on the

network (Flight mode)

DRx

GSM 4.7 mA DRx5

WCDMA 4.7 mA DRx6

3.6 mA DRx7

3.1 mA DRx8

2.8 mA DRx9

LTE 7.7 mA Paging cycle #32 frames (0.32 sec DRx cycle)

5.1 mA Paging cycle #64 frames (0.64 sec DRx cycle)

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

55 of 104

Mode Average (Typ.)

Mode Description

3.8 mA Paging cycle #128 frames (1.28 sec DRx cycle)

3.2 mA Paging cycle #256 frames (2.56 sec DRx cycle)

Operative Mode (LTE)

LTE (0dBm)

300 mA LTE data call (Non-CA BW 5 MHz, RB=1)

500 mA LTE data call (CA BW 20 + 20MHz, Full RB, B4+B4 Intra

CA, FDD 300 Mbps DL / 50 Mbps UL) without Ethernet

750 mA LTE data call (CA BW 20 + 20MHz, Full RB, B4+B4 Intra

CA, FDD 300 Mbps DL / 50 Mbps UL) with Ethernet

LTE (23dBm)

760 mA LTE data call (Non-CA BW 5MHz, RB=1)

1000 mA LTE data call (CA BW 20 + 20MHz, Full RB, B4+B4 Intra

CA, FDD 300 Mbps DL / 50 Mbps UL) without Ethernet

1250 mA LTE data call (CA BW 20 + 20MHz, Full RB, B4+B4 Intra

CA, FDD 300 Mbps DL / 50 Mbps UL) with Ethernet

Operative Mode (WCDMA)

WCDMA Voice 690 mA WCDMA voice call (Tx = 23 dBm)

WCDMA HSDPA

(0 dBm)

300 mA WCDMA data call (DC-HSDPA up to 42 Mbps, Max

Throughput) without Ethernet

550 mA WCDMA data call (DC-HSDPA up to 42 Mbps, Max

Throughput) with Ethernet

WCDMA HSDPA

(23 dBm)

700 mA WCDMA data call (DC-HSDPA up to 42 Mbps, Max

Throughput) without Ethernet

950 mA WCDMA data call (DC-HSDPA up to 42 Mbps, Max

Throughput) with Ethernet

Operative Mode (GSM)

GSM Tx and Rx mode

GSM 850/900 PL5 360 mA GSM voice call

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

56 of 104

Mode Average (Typ.)

Mode Description

GSM 1800/1900

PL0

300 mA

GPRS 4 Tx + 1 Rx

GSM 850/900 PL5 750 mA

GPRS Sending Data mode (CS-4)

DCS 1800/1900 PL0

550 mA

EGPRS 4 Tx + 1 Rx

GSM 850/900 PL8 550 mA

GPRS Sending Data mode (MCS-5)

DCS 1800/1900 PL2

500 mA

* Worst/best case current values depend on network configuration, not under module control.

** Applied MPR –2dB 16-QAM full RB

*** 3.8V voltage/room temperature

NOTE:

Differences in measurement technique, equipment, or temperature can cause variations in

current consumption measurements.

NOTE:

The electrical design for the power supply must ensure a peak current output of at least 2.0A.

NOTE:

In GSM/GPRS mode, RF transmission is not continuous, but is packed into bursts at a base

frequency of about 216 Hz with relative current peaks as high as about 2.0A. Therefore, the

power supply must be designed to withstand these current peaks without big voltage drops. This

means that both the electrical design and the board layout must be designed for this current

flow.

If the layout of the PCB is not well designed, a strong noise floor is generated on the ground. This

will reflect on all the audio paths producing an audible annoying noise at 216 Hz.

If the voltage drops during the peaks, current absorption is too high. The device may even shut

down as a consequence of the supply voltage drop.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

57 of 104

6.2. General Design Rules

The principal guidelines for the Power Supply Design embrace three different design steps:

• Electrical design

• Thermal design

• PCB layout

6.2.1. Electrical Design Guidelines

The electrical design of the power supply depends strongly on the power source where this

power is drained. Power sources can be distinguished by three categories:

• +5V input (typically PC internal regulator output)

• +12V input (typically automotive)

• Battery

6.2.1.1. + 5V Input Source Power Supply – Design Guidelines

• The desired output for the power supply is 3.8V. So, the difference between the input source

and the desired output is not big, and therefore a linear regulator can be used. A switching

power supply is preferred to reduce power consumption.

• When using a linear regulator, a proper heat sink must be provided to dissipate the power

generated.

• A bypass low ESR capacitor of adequate capacity must be provided to cut the current

absorption peaks close to the LE940B6 module. A 100 μF tantalum capacitor is usually

suitable on both VBATT and VBATT_PA power lines.

• Make sure that the low ESR capacitor on the power supply output (usually a tantalum one) is

rated at least 10V.

• A protection diode must be inserted close to the power input to protect the LE940B6 module

from power polarity inversion.

Figure 12 shows an example of linear regulator with 5V input.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

58 of 104

Figure 12: Example of Linear Regulator with 5V Input

6.2.1.2. + 12V Input Source Power Supply – Design Guidelines

• The desired output for the power supply is 3.8V. Due to the big difference between the input

source and the desired output, a linear regulator is unsuitable and must not be used. A

switching power supply is preferable because of its better efficiency, especially with the

2A peak current load expected when working with the LE940B6.

• When using a switching regulator, a 500-kHz or higher switching frequency regulator is

preferable because of its smaller inductor size and its faster transient response. This allows

the regulator to respond quickly to the current peaks absorption.

• In any case, the selection of the frequency and switching design is related to the application

to be developed due to the fact that the switching frequency can also generate EMC

interference.

• For car batteries (lead-acid accumulators) the input voltage can rise up to 15.8V. This must be

kept in mind when choosing components: all components in the power supply must

withstand this voltage.

• A bypass low ESR capacitor of adequate capacity must be provided to cut the current

absorption peaks. A 100μF tantalum capacitor is usually suitable on VBATT & VBATT_PA

power lines.

• Make sure that the low ESR capacitor on the power supply output (usually a tantalum one) is

rated at least 10V.

• For automotive applications, a spike protection diode must be inserted close to the power

input to clean the supply of spikes.

• A protection diode must be inserted close to the power input to protect the LE940B6 module

from power polarity inversion. This can be the same diode as for spike protection.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

59 of 104

Figure 13 and Figure 14 show an example of switching regulator with 12V input.

Figure 13: Example of Switching Regulator with 12V Input – Part 1

Figure 14: Example of Switching Regulator with 12V Input – Part 2

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

60 of 104

6.2.1.3. Battery Source Power Supply – Design Guidelines

• The desired nominal output for the power supply is 3.8V, and the maximum allowed voltage

is 4.2V. Hence, a single 3.7V Li-Ion cell battery type is suitable for supplying the power to the

LE940B6 module.

NOTE:

Do not use any Ni-Cd, Ni-MH, and Pb battery types directly connected to the LE940B6 module.

Their use can lead to overvoltage on the LE940B6 and damage it. Use only Li-Ion battery types.

• A bypass low ESR capacitor of adequate capacity must be provided to cut the current

absorption peaks; a 100μF tantalum capacitor is usually suitable.

• Make sure that the low ESR capacitor (usually a tantalum one) is rated at least 10V.

• A protection diode must be inserted close to the power input to protect the LE940B6 module

from power polarity inversion. Otherwise, the battery connector must be done in a way to

avoid polarity inversions when connecting the battery.

• The battery capacity must be at least 500 mAh to withstand the current peaks of 2A. The

suggested capacity is from 500 mAh to 1000 mAh.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

61 of 104

6.2.2. Thermal Design Guidelines

The thermal design for the power supply heat sink must be done with the following specifications:

• Average current consumption during LTE 2xCA DL Max throughput @PWR level max in

LE940B6: 1250 mA

NOTE:

The average consumption during transmission depends on the power level at which the device is

requested to transmit via the network. Therefore, the average current consumption varies

significantly.

In LTE mode, the LE940B6 emits RF signals continuously during transmission. Therefore, pay

special attention to how the generated heat is dissipated.

The current consumption is up to about 1250 mA in 2xCA Max throughput, and 1250 mA in LTE

continuously at the maximum Tx output power 23.0 dBm.

The current consumption is up to about 1250 mA continuously at the maximum Tx output power

(23 dBm). Therefore, make sure on the PCB used to mount LE940B6, that the area under the

LE940B6 module is as large as possible. Make sure that the LE940B6 is mounted on the large

ground area of application board and provide many ground vias to dissipate the heat.

6.2.3. Power Supply PCB Layout Guidelines

As seen in the electrical design guidelines, the power supply must have a low ESR capacitor on the

output to cut the current peaks and a protection diode on the input to protect the supply from

spikes and polarity inversion. The placement of these components is crucial for the correct

operation of the circuitry. A misplaced component can be useless or can even decrease the power

supply performances.

• The bypass low ESR capacitor must be placed close to the LE940B6 power input pads, or if the

power supply is of a switching type, it can be placed close to the inductor to cut the ripple, as

long as the PCB trace from the capacitor to LE940B6 is wide enough to ensure a drop-less

connection even during the 2A current peaks.

• The protection diode must be placed close to the input connector where the power source is

drained.

• The PCB traces from the input connector to the power regulator IC must be wide enough to

ensure that no voltage drops occur during the 2A current peaks.

Note that this is not done to save power loss but especially to avoid the voltage drops on the

power line at the current peaks frequency of 216 Hz that will reflect on all the components

connected to that supply (also introducing the noise floor at the burst base frequency.)

For this reason while a voltage drop of 300-400 mV may be acceptable from the power loss

point of view, the same voltage drop may not be acceptable from the noise point of view. If

your application does not have an audio interface but only uses the data feature of the

LE940B6, this noise is not so disturbing, and the power supply layout design can be more

forgiving.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

62 of 104

• The PCB traces to LE940B6 and the bypass capacitor must be wide enough to ensure that no

significant voltage drops occur when the 2A current peaks are absorbed. This is needed for

the same above-mentioned reasons. Try to keep these traces as short as possible.

• The PCB traces connecting the switching output to the inductor and the switching diode must

be kept as short as possible by placing the inductor and the diode very close to the power

switching IC (only for the switching power supply). This is done to reduce the radiated field

(noise) at the switching frequency (usually 100-500 kHz).

• Use a good common ground plane.

• Place the power supply on the board in a way to guarantee that the high current return paths

in the ground plane do not overlap any noise sensitive circuitry, such as the microphone

amplifier/buffer or earphone amplifier.

• The power supply input cables must be kept separate from noise sensitive lines, such as

microphone/earphone cables.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

63 of 104

7. Antenna(s)

Antenna connection and board layout design are the most important parts in the full product

design, and they have a strong influence on the product’s overall performance. Read carefully and

follow the requirements and guidelines for a good and proper design.

7.1. GSM/WCDMA/TD-SCDMA/LTE Antenna Requirements

The antenna for the LE940B6 device must meet the following requirements:

Table 22: Primary Antenna Requirements

Gain Gain < 3 dBi

Impedance 50 Ohm

Input power > 33 dBm(2 W) peak power in GSM

> 24 dBm average power in WCDMA & LTE

VSWR absolute max <= 10:1

VSWR recommended <= 2:1

The antenna for a specific car model must support a given set of RF bands. This set is determined

by the region variant and the specific set of bands within (either the full band set offered by Telit

or a subset per the customer choice). The antenna must have the proper bandwidth to support

the required set of bands and meet the other performance figures according to the Table 22,

along the full bandwidth. The RF bands supported in each region variant are detailed in

Section 2.5.1, RF Bands per Regional Variant.

Since there is no antenna connector on the LE940B6 module, the antenna must be connected to

the LE940B6 antenna pad (AD1) by a transmission line implemented on the PCB.

If the antenna is not directly connected to the antenna pad of the LE940B6, a PCB line is required

to connect to it or to its connector.

7.2. GSM/WCDMA/TD-SCDMA/LTE Antenna – PCB Line Guidelines

• Make sure that the transmission line’s characteristic impedance is 50 Ohm.

• Keep the line on the PCB as short as possible since the antenna line loss should be less than

around 0.3 dB.

• Line geometry should have uniform characteristics, constant cross sections, and avoid

meanders and abrupt curves.

• Any suitable geometry/structure can be used for implementing the printed transmission line

affecting the antenna.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

64 of 104

• If a ground plane is required in the line geometry, this plane must be continuous and

sufficiently extended so the geometry can be as similar as possible to the related canonical

model.

• Keep, if possible, at least one layer of the PCB used only for the ground plane. If possible, use

this layer as reference ground plane for the transmission line.

• Surround the PCB transmission line with ground (on both sides). Avoid having other signal

tracks facing the antenna line track directly.

• Avoid crossing any un-shielded transmission line footprint with other tracks on different

layers.

• The ground surrounding the antenna line on the PCB must be strictly connected to the main

Ground plane by means of via-holes (once per 2 mm at least) placed close to the ground

edges facing the line track.

• Place EM-noisy devices as far as possible from LE940B6 antenna line.

• Keep the antenna line far away from the LE940B6 power supply lines.

• If EM-noisy devices are present on the PCB hosting the LE940B6, such as fast switching ICs,

take care to shield them with a metal frame cover.

• If EM-noisy devices are not present around the line, geometries like Micro strip or Grounded

Coplanar Waveguide are preferred because they typically ensure less attenuation compared

to a Strip line having the same length.

This transmission line must meet the following requirements:

Table 23: Antenna Line on PCB Requirements

Characteristic impedance 50 Ohm

Max attenuation 0.3 dB

Avoid coupling with other signals.

Cold End (Ground Plane) of the antenna must be equipotential to the LE940B6 ground pads.

Furthermore if the device is developed for the US and/or Canada market, it must comply with the

FCC and/or IC approval requirements:

This device is to be used only for mobile and fixed application. The antenna(s) used for this

transmitter must be installed to provide a separation distance of at least 20 cm from all persons

and must not be co-located or operating in conjunction with any other antenna or transmitter. End-

Users must be provided with transmitter operation conditions for satisfying RF exposure compliance.

OEM integrators must ensure that the end user has no manual instructions to remove or install the

LE940B6 module. Antennas used for this OEM module must not exceed 3dBi gain for mobile and

fixed operating configurations.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

65 of 104

7.3. GSM/WCDMA/TD-SCDMA/LTE Antenna – Installation Guidelines

• Install the antenna in a location with access to the network radio signal.

• The antenna must be installed such that it provides a separation distance of at least 20 cm

from all persons and must not be co-located or operating in conjunction with any other

antenna or transmitter.

• The antenna must not be installed inside metal cases.

• The antenna must be installed according to the antenna manufacturer’s instructions.

7.4. Secondary Antenna Requirements

This product includes an input for a second Rx antenna to improve radio sensitivity. The function

is called Antenna Diversity.

Since there is no antenna connector on the LE940B6 module, the antenna must be connected to

the LE940B6 antenna pad by means of a transmission line implemented on the PCB.

If the antenna is not directly connected at the antenna pad of the LE940B6 (AU9), a PCB line is

required to connect to it or to its connector.

The second Rx antenna must not be located in close vicinity of the main antenna. To improve

diversity gain and isolation and to reduce mutual interaction, the two antennas should be located

at the maximum reciprocal distance possible, taking into consideration the available space within

the application.

NOTE:

If Rx Diversity is not used/connected, disable the Diversity functionality using the AT+XRXDIV

command (refer to Ref 1: LE940B6 AT Command Reference Guide) and connect the Diversity pad

AU9 to a 50 Ohm termination.

7.5. PCB Guidelines in case of FCC certification

In the case FCC certification is required for an application using LE940B6-NA, according to FCC

KDB 996369 for modular approval requirements, the transmission line has to be similar to that

implemented on module’s interface board and described in the following chapter.

7.5.1. Transmission line design

During the design of the interface board, the placement of components has been chosen

properly, in order to keep the line length as short as possible, thus leading to lowest power losses

possible. A Grounded Coplanar Waveguide (G-CPW) line has been chosen, since this kind of

transmission line ensures good impedance control and can be implemented in an outer PCB layer

as needed in this case. A SMA female connector has been used to feed the line.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

66 of 104

The interface board is realized on a FR4, 4-layers PCB. Substrate material is characterized by

relative permittivity εr = 4.6 ± 0.4 @ 1 GHz, TanD= 0.019 ÷ 0.026 @ 1 GHz.

A characteristic impedance of nearly 50 Ω is achieved using trace width = 1.1 mm, clearance from

coplanar ground plane = 0.3 mm each side. The line uses reference ground plane on layer 3, while

copper is removed from layer 2 underneath the line. Height of trace above ground plane is 1.335

mm. Calculated characteristic impedance is 51.6 Ω, estimated line loss is less than 0.1 dB. The line

geometry is shown below:

7.5.2. Transmission line measurements

E5071C NA (Full-4-port calibration) has been used in this measurement session. A calibrated

coaxial cable has been soldered at the pad corresponding to RF output; a SMA connector has

been soldered to the board in order to characterize the losses of the transmission line including

the connector itself. During Return Loss / impedance measurements, the transmission line has

been terminated to 50 Ω load.

Return Loss plot of line under test is shown below:

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

67 of 104

Line input impedance (in Smith Chart format, once the line has been terminated to 50 Ω load) is

shown in the following figure:

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

68 of 104

Insertion Loss of G-CPW line plus SMA connector is shown below:

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

69 of 104

8. Hardware Interfaces

Table 24 summarizes all the hardware interfaces of the LE940B6 module.

Table 24: LE940B6 Hardware Interfaces

LE940B6 (XMM7272 CAT6)

Ethernet RMII/RGMII

USB USB2.0

SPI Master only, up to 26 MHz (104 MHz @ Kernel CLK/4)

I2C For sensors, audio control

UART x1 UART for AT (up to 4.8 Mbps)

x1 UART for diagnosis (up to 4.8 Mbps)

x1 UART for GNSS or external controller (up to 4.8 Mbps)

Audio I/F I2S/PCM, Analog audio

GPIO 15 dedicated GPIO

USIM X2, dual voltage each (1.8/2.9V);

SIM chip integration not possible

ADC Up to x3

Antenna ports 2 for Cellular, 1 for GNSS

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

70 of 104

8.1. USB Port

The LE940B6 module includes a Universal Serial Bus (USB) transceiver, which operates at USB

high-speed (480Mbits/sec). It can also operate with USB full-speed hosts (12Mbits/sec).

It is compliant with the USB 2.0 specification and can be used for control and data transfers as

well as for diagnostic monitoring and firmware update.

NOTE:

With the LE940B6 module, firmware updates by the host are only possible via USB and not

possible via UART. The reason is that Telit considers it impractical to transfer firmware binaries

exceeding 100Mb via UART.

The USB port is typically the main interface between the LE940B6 module and OEM hardware.

NOTE:

The USB_D+ and USB_D- signals have a clock rate of 480 MHz. The signal traces must be routed

carefully. Minimize trace lengths, number of vias, and capacitive loading. The impedance value

should be as close as possible to 90 Ohms differential.

The pull-up, pull-down and series resistors on pins USB_D+ and USB_D- as required by the USB

2.0 specification are included inside the module.

Table 25 lists the USB interface signals.

Table 25: USB Interface Signals

Signal Pad

No.

Usage

USB_VBUS A18 Power and cable detection for the internal USB transceiver.

Acceptable input voltage range 2.5V – 5.5V @ max 5 mA consumption

USB_D- F19 Minus (-) line of the differential, bi-directional USB signal to/from the

peripheral device

USB_D+ D19 Plus (+) line of the differential, bi-directional USB signal to/from the

peripheral device

NOTE:

USB_VBUS input power is internally used to detect the USB port and start the enumeration

process. It is not used for supplying power to the internal LE940B6 USB HW block.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

71 of 104

NOTE:

Even if USB communication is not used, it is still highly recommended to place an optional USB

connector on the application board.

At least test points of the USB signals are required since the USB physical communication is

needed in the case of SW update.

Warning:

Consider placing low-capacitance ESD protection device to protect LE940B6 against ESD strikes.

If an ESD protection should be added, the suggested connectivity is as follows:

Figure 15: ESD Protection for USB2.0

8.2. Serial Ports

The serial port is typically a secondary interface between the LE940B6 module and OEM

hardware. The following serial ports are available on the module:

• Modem Serial Port 1 (Main)

• Modem Serial Port 2 (Auxiliary)

• Modem Serial Port 3 (GNSS)

Several serial port configurations can be designed for the OEM hardware. The most common are:

• RS232 PC com port

• Microcontroller UART @ 1.8V (Universal Asynchronous Receive Transmit)

• Microcontroller UART @ 3.3V/5V or other voltages different from 1.8V

Depending on the type of serial port on OEM hardware, level translator circuits may be needed to

make the system operate. The only configuration that does not need level translation is the 1.8V

UART. The LE940B6 UART has CMOS levels as described in Section 4.3.1, 1.8V Standard GPIOs.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

72 of 104

8.2.1. Modem Serial Port 1

Serial Port 1 is a +1.8V UART, having all the 8 RS232 signals. It differs from the PC-RS232 in the

signal polarity (RS232 is reversed) and levels. Table 26 lists the signals of LE940B6 Serial Port 1.

Table 26: Modem Serial Port 1 Signals

RS232 Pin #

Signal Pad No.

Name Usage

1 DCD -

DCD_UART

AE18 Data Carrier

Detect

Output from LE940B6 that

indicates carrier presence

2 RXD -

TX_UART

AF19 Transmit line

*see Note

Output transmit line of LE940B6

UART

3 TXD -

RX_UART

AH19 Receive line

*see Note

Input receive line of LE940B6 UART

4 DTR -

DTR_UART

AC18 Data Terminal

Ready

Input to LE940B6 that controls the

DTE READY condition

5 DSR -

DSR_UART

AG18 Data Set Ready Output from LE940B6 that

indicates that the module is ready

6 RTS -

RTS_UART

AA18 Request to Send

Input to LE940B6 controlling the

Hardware flow control

7 CTS -

CTS_UART

AK19 Clear to Send Output from LE940B6 controlling

the Hardware flow control

8 RI -

RI_UART

AJ18 Ring Indicator Output from LE940B6 indicating

the Incoming call condition

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

NOTE:

For minimum implementations, only the TXD and RXD lines need be connected. The other lines

can be left open provided a software flow control is implemented.

NOTE:

According to V.24, Rx/Tx signal names refer to the application side; therefore, on the LE940B6

side, these signal are in the opposite direction: TXD on the application side will be connected to

the receive line (here named TXD/ RX_UART) of the LE940B6 serial port and vice versa for Rx.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

73 of 104

8.2.2. Modem Serial Port 2

On the LE940B6, Serial Port 2 is a +1.8V UART with Rx and Tx signals only.

Table 27 lists the signals of the LE940B6 Serial Port 2.

Table 27: Modem Serial Port 2 Signals

PAD Signal I/O

Function Type

COMMENT

AB19 TXD_AUX O Auxiliary UART (Tx Data to DTE) 1.8V

AD19 RXD_AUX I Auxiliary UART (Rx Data to DTE) 1.8V

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

NOTE:

The Auxiliary UART is used as the SW main debug console. It is required to place test points on

this interface even if not used.

8.2.3. Modem Serial Port 3

Serial port 3 is a +1.8V UART with all 4 RS232 signals. It differs from the PC-RS232 in the signal

polarity (RS232 is reversed) and levels. Table 28 lists the signals of the LE940B6 Serial Port 3.

Table 28: Modem Serial Port 3 Signals

PAD Signal I/O

Function Type

Comment

AM9 UART3_TXD

I Serial data input (TXD) from DTE 1.8V

AM11

UART3_RXD

O Serial data output (RXD) to DTE 1.8V

AM13

UART3_RTS

I Input for Request to Send (RTS) from DTE

1.8V

AM15

UART3_CTS

O Output for Clear to Send (CTS) to DTE 1.8V

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

74 of 104

8.2.4. RS232 Level Translation

To interface the LE940B6 with a PC COM port or an RS232 (EIA/TIA-232) application, a level

translator is required. This level translator must perform the following actions:

• Invert the electrical signal in both directions

• Change the level from 0/1.8V to +15/-15V

The RS232 UART 16450, 16550, 16650 & 16750 chipsets accept signals with lower levels on the

RS232 side (EIA/TIA-562), allowing a lower voltage-multiplying ratio on the level translator. Note

that the negative signal voltage must be less than 0V and hence some sort of level translation is

always required.

The simplest way to translate the levels and invert the signal is by using a single chip-level

translator. There are a multitude of them, differing in the number of drivers and receivers and in

the levels (be sure to get a true RS232 level translator, not a RS485 or other standards).

By convention, the driver is the level translator from the 0-1.8V UART to the RS232 level. The

receiver is the translator from the RS232 level to 0-1.8V UART. To translate the whole set of

control lines of the UART, the following is required:

• 2 drivers

• 2 receivers

Warning:

The digital input lines, operating at 1.8V CMOS levels, have absolute maximum input voltage of

2.0V. The level translator IC outputs on the module side (i.e. LE940B6 inputs) will cause

damage to the module inputs if the level translator is powered with +3.8V power.

So the level translator IC must be powered from a dedicated +1.8V power supply.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

75 of 104

As an example of RS232 level adaption circuitry could use a MAXIM transceiver (MAX218). In this

case, the chipset is capable of translating directly from 1.8V to the RS232 levels (Example on 4

signals only).

Figure 16: RS232 Level Adaption Circuitry Example

NOTE:

In this case, the length of the lines on the application must be taken into account to avoid

problems in the case of High-speed rates on RS232.

The RS232 serial port lines are usually connected to a DB9 connector as shown in Figure 17. Signal

names and directions are named and defined from the DTE point of view.

Figure 17: RS232 Serial Port Lines Connection Layout

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

76 of 104

8.3. Peripheral Ports

In addition to the LE940B6 serial ports, the LE940B6 supports the following peripheral ports:

• SPI – Serial Peripheral Interface

• I2C - Inter-integrated circuit

• Ethernet – Ethernet PHY Interface

8.3.1. SPI – Serial Peripheral Interface

The LE940B6 SPI supports the following:

• Master Mode only

• 1.8V CMOS level

• Up to 26 MHz clock rate

NOTE:

SPI is supported only on the Linux side.

The LE940B6 module supports Master mode only and cannot be configured as Slave mode.

Table 29: SPI Signals

PAD Signal I/O Function Type Comment

P19 SPI_CLK O SPI clock output 1.8V

M19 SPI_MISO

I SPI data Master input Slave output 1.8V

K19 SPI_MOSI

O SPI data Master output Slave input 1.8V

N18 SPI_CS O SPI chip-select output 1.8V

Figure 18: SPI Signal Connectivity

LE940B6 (Master)

SPI_CS

SPI_CLK

SPI_MOSI

SPI_MISO

Host (Slave)

SPI_CS

SPI_CLK

SPI_MOSI

SPI_MISO

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

77 of 104

8.3.2. I2C - Inter-integrated Circuit

The LE940B6 I2C is an alternate function of GPIO 1-15 pins. Available only from Modem side as

SW emulation of I2C on GPIO lines. Any GPIO can be configured as SCL or SDA. LE940B6 supports

I2C Master Mode only.

NOTE:

SW emulated I2C on GPIO lines is supported only from the modem side. For more information,

refer to Ref 1: LE940B6 AT Command Reference Guide for command settings.

8.4. Ethernet Interface

The LE940B6 has an integrated Ethernet interface to an external Ethernet PHY supporting 10M /

100M and 1G speed modes via a RGMII interface.

The Ethernet interface is target to be compliant with the RGMII and RMII specifications. The

supported RGMII and RMII specification versions are:

• RGMII: Version 1.3, dated 12/10/2000, supporting up to 1000 Mbps operation

• RMII: Version 1.2, dated 03/20/1998, supporting up to 100 Mbps operation

NOTE:

Customer should carefully design the Ethernet interface depending on PHY chipset; Please

contact Telit R&D for more details and guidelines.

Table 30: Ethernet Interface

PAD Signal I/O

Function Type COMMENT

G14 MAC_MDC O Management Data Clock 2.5/3.3V

G12 MAC_MDIO I/O

Management Data I/O 2.5/3.3V

V16 MAC_TXD[0] O RGMII or RMII TXD[0] 2.5/3.3V

T16 MAC_TXD[1] O RGMII or RMII TXD[1] 2.5/3.3V

R16 MAC_TXD[2] O RGMII TXD[2] 2.5/3.3V

N16 MAC_TXD[3] O RGMII TXD[3] 2.5/3.3V

L16 MAC_GTX_CLK O RGMII Transmit Clock 2.5/3.3V

G16 MAC_TXEN_ER

O RGMII Transmit Enable /Error or

RMII Transmit Enable

2.5/3.3V

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

78 of 104

PAD Signal I/O

Function Type COMMENT

AL16 MAC_RXD[0] I RGMII or RMII RXD[0] 2.5/3.3V

AJ16 MAC_RXD[1] I RGMII or RMII RXD[1] 2.5/3.3V

AG16

MAC_RXD[2] I RGMII RXD[2] 2.5/3.3V

AE16 MAC_RXD[3] I RGMII RXD[3] 2.5/3.3V

AC16 MAC_RX_CLK I RGMII Receive Clock 2.5/3.3V

X16 MAC_RXDV_ER

I RGMII Receive Data Available/Error

or RMII Receive Error

2.5/3.3V

G10 ETH_INT_N I Ethernet PHY Interrupt 2.5/3.3V

G8 ETH_RST_N O Ethernet PHY Reset Output 2.5/3.3V

8.5. Audio Interface

The LE940B6 module supports analog and digital audio interfaces.

8.5.1. Analog Audio

The LE940B6 module provides an analog audio interface; a single differential input for the audio

to be transmitted (Uplink), and a balanced output for the received audio (Downlink). The analog

interface is on the following pins:

Table 31: Analog Audio Signals

PAD

Signal I/O

Function Type Comments

B5 EAR1_MT+ AO

Earphone signal output, phase + Audio

A4 EAR1_MT- AO

Earphone signal output, phase - Audio

B3 MIC1_MT+ AI Microphone signal input, phase + Audio

A2 MIC1_MT- AI Microphone signal input, phase - Audio

G6 MICBIAS AO

Microphone bias is 1.9~2.2V Power

For more details, Application Note will be prepared for the Audio Settings.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

79 of 104

8.5.2. Digital Audio

The LE940B6 module can be connected to an external codec through the digital interface.

The product provides a single Digital Audio Interface (DVI) on the following pins:

Table 32: Digital Audio Interface (DVI) Signals

PAD

Signal I/O

Function Type Comments

D11 DVI_WA0

O Digital Audio Interface (WA0) B-PD 1.8V PCM_SYNC

C8 DVI_RX I Digital Audio Interface (RX) B-PD 1.8V PCM_DIN

D9 DVI_TX O Digital Audio Interface (TX) B-PD 1.8V PCM_DOUT

C10 DVI_CLK O Digital Audio Interface (CLK) B-PD 1.8V PCM_CLK

8.6. General Purpose I/O

The general-purpose I/O pads can be configured to act in three different ways:

• Input

• Output

• Alternative function (internally controlled)

Input pads can only be read, reporting digital values (high / low) present at the reading time.

Output pads can only be written or queried and set values on the pad output. Alternative function

can be internally controlled by LE940B6 firmware and act according to the implementation.

The type of GPIO can be set to Open-drain signaling; default type is CMOS mode.

Table 33: GPIOs

PAD Signal I/O Function Type Drive Strength

F9 GPIO_01 I/O Configurable GPIO CMOS 1.8V 1 mA

E10 GPIO_02 I/O Configurable GPIO CMOS 1.8V 1 mA

F11 GPIO_03 I/O Configurable GPIO CMOS 1.8V 3 mA

E12 GPIO_04 I/O Configurable GPIO CMOS 1.8V 3 mA

F13 GPIO_05 I/O Configurable GPIO CMOS 1.8V 1 mA

E14 GPIO_06 I/O Configurable GPIO CMOS 1.8V 3 mA

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

80 of 104

PAD Signal I/O Function Type Drive Strength

R18 GPIO_07 I/O Configurable GPIO CMOS 1.8V 3 mA

S19 GPIO_08 I/O Configurable GPIO CMOS 1.8V 3 mA

U19 GPIO_09 I/O Configurable GPIO CMOS 1.8V 3 mA

W19 GPIO_10 I/O Configurable GPIO CMOS 1.8V 3 mA

L18 GPIO_11 I/O Configurable GPIO CMOS 1.8V 3 mA

J18 GPIO_12 I/O Configurable GPIO CMOS 1.8V 3 mA

AN4 GPIO_20 I/O Configurable GPIO CMOS 1.8V 3 mA

H1 GPIO_21 I/O Configurable GPIO CMOS 1.8V 3 mA

K1 GPIO_22 I/O Configurable GPIO CMOS 1.8V 4 mA

NOTE:

To avoid a back-powering effect, it is recommended to avoid having any HIGH logic level signal

applied to the digital pins of the module when it is powered OFF or during an ON/OFF transition.

NOTE:

LE940B6 GPIOs can also be used as alternate I2C function. Refer to Section 8.3.2, I2C - Inter-

integrated Circuit.

8.6.1. Using a GPIO Pad as Input

GPIO pads, when used as inputs, can be connected to a digital output of another device and

report its status, provided this device has interface levels compatible with the 1.8V CMOS levels

of the GPIO.

If the digital output of the device is connected with the GPIO input, the pad has interface levels

different from the 1.8V CMOS. It can be buffered with an open collector transistor with a 10 kΩ

pull-up resistor to 1.8V.

8.6.2. Using a GPIO Pad as Output

GPIO pads, when used as outputs, can drive 1.8V CMOS digital devices or compatible hardware.

When set as outputs, the pads have a push-pull output, and therefore the pull-up resistor can be

omitted.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

81 of 104

Figure 19: GPIO Output Pad Equivalent Circuit

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

82 of 104

9. Miscellaneous Functions

9.1. Indication of Network Service Availability

The STAT_LED pin status shows information on the network service availability and call status.

In the LE940B6 module, the STAT_LED usually needs an external transistor to drive an external

LED.

The status indicated in Table 34 is configurable. Refer to Ref 1: LE940B6 AT Command Reference

Guide for the full description of this function.

Table 34: Network Service Availability Indication

LED Status Device Status

Permanently off Device off

Fast blinking (Period depends on network condition) Registered with power saving

Slow blinking (Period 3s, T

1s) Registered with full service

Permanently on A call is active

Figure 20: Status LED circuit example

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

83 of 104

9.2. RTC – Real Time Clock

The VRTC pin is used to power the RTC only when the main battery voltage level is too low or

missing.

9.3. VAUX Power Output

A regulated power supply output is provided to supply small devices from the module. This

output is active when the module is ON and goes OFF when the module is shut down. The

operating range characteristics of the supply are as follows:

Table 35: Operating Range – VAUX Power Supply

Min Typical Max

Output voltage 1.75V 1.80V 1.85V

Output current 100 mA

Output bypass capacitor (within the module)

1 μF

9.4. ADC Converter

9.4.1. Description

The LE940B6 module provides three on-board 12-bit Analog to Digital converters. Each ADC reads

the voltage level applied on the relevant pin, converts it and stores it into a 16-bit word.

Table 36: ADC Parameters

Min Max Units

Input voltage range 0 1.2 Volt

AD conversion - 12 bits

9.4.2. Using the ADC Converter

An AT command is available to use the ADC function.

The command is AT#ADC=1,2. The read value is expressed in mV.

Refer to Ref 1: LE940B6 AT Command Reference Guide for the full description of this function.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

84 of 104

9.5. Using the Temperature Monitor Function

The Temperature Monitor supports temperature monitoring by giving periodic temperature

indications, to execute some function at extreme state. If properly set (see the #TEMPMON

command in the Ref 1: LE940B6 AT Command Reference Guide), it raises a GPIO to High Logic

level when the maximum temperature is reached.

9.6. Fuel Gauge (TBD)

The LE940B6 module can optionally support an external Fuel Gauge solution.

In this case, an external IC that is capable of measuring the current flow in and out of the module

must be added on the carrier board.

Figure 21 shows an example of a typical connectivity of such an external fuel gauge to the

LE940B6 module.

Detailed design - TBD

Figure 21: Fuel Gauge Connectivity Example

9.7. eFuse

The LE940B6 needs 1.8 +/- 0.05V applied on pad VPP(H17) for eFuses being programmed.

The fuse voltage should be applied to VPP(H17) prior to the fuse script being started, and should

be removed after the fuse operation has been completed.

Warning:

Fuse voltage must never be supplied when the module is not powered up.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

85 of 104

10. Mounting the Module on your Board

10.1. General

The LE940B6 module is designed to be compliant with a standard lead-free soldering process as

defined in JESD22b102d, table 3b. The number of reflows must not exceed two. This limits Tmax

to 245 °C.

10.2. Finishing & Dimensions

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

86 of 104

10.3. Recommended Footprint for the Application

Figure 22 shows the top view of the module, which has 334 pads (dimensions are in mm).

To facilitate replacing the LE940B6 module if necessary, it is suggested to design the application

board with a 1.5 mm placement inhibit area around the module. These regions are highlighted in

Figure 22.

It is also suggested, as a common rule for an SMT component, to avoid having a mechanical part

of the application board in direct contact with the module.

NOTE:

In the customer application, the region marked as INHIBIT WIRING in Figure 22 must be clear of

signal wiring or ground polygons.

Figure 22: Application Module Top View

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

87 of 104

10.4. Stencil

Stencil’s apertures layout can be the same as the recommended footprint (1:1). The suggested

thickness of stencil foil is greater than 120 µm.

10.5. PCB Pad Design

The solder pads on the PCB are recommended to be of the Non Solder Mask Defined (NSMD)

type.

Figure 23: PCB Pad Design

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

88 of 104

10.6. Recommendations for PCB Pad Dimensions (mm)

Figure 24: PCB Pad Dimensions

It is not recommended to place around the pads a via or micro-via that is not covered by solder

resist in an area of 0.3 mm unless it carries the same signal as the pad itself (see Figure 25).

Figure 25: Inhibit Area for Micro-via

Holes in pad are allowed only for blind holes and not for through holes.

Table 37: Recommendations for PCB Pad Surfaces

Finish Layer Thickness (um)

Properties

Electro-less Ni / Immersion Au 3-7 / 0.05-0.15 Good solder ability

protection, high shear force

values

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

89 of 104

The PCB must be able to resist the higher temperatures, which occur during the lead-free process.

This issue should be discussed with the PCB-supplier. Generally, the wettability of tin-lead solder

paste on the described surface plating is better compared to lead-free solder paste.

10.7. Solder Paste

We recommend using only “no clean” solder paste to avoid the cleaning of the modules after

assembly.

10.7.1. Solder Reflow

Figure 26 shows the recommended solder reflow profile.

Figure 26: Solder Reflow Profile

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

90 of 104

Table 38: Solder Profile Characteristics

Profile Feature Pb-Free Assembly

Average ramp-up rate (T

to T

) 3°C/second max

Preheat

– Temperature min (Tsmin)

– Temperature max (Tsmax)

– Time (min to max) (ts)

150°C

200°C

60-180 seconds

Tsmax to TL

– Ramp-up rate

3°C/second max

Time maintained above:

– Temperature (TL)

– Time (tL)

217°C

60-150 seconds

Peak temperature (Tp) 245 +0/-5°C

Time within 5°C of actual peak

Temperature (tp)

10-30 seconds

Ramp-down rate 6°C/second max

Time 25°C to peak temperature 8 minutes max

NOTE:

All temperatures refer to topside of the package, measured on the package body surface.

Warning:

The LE940B6 module withstands one reflow process only.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

91 of 104

11. Application Guide

11.1. Debug of the LE940B6 Module in Production

To test and debug the mounting of the LE940B6 module, we strongly recommend to add several

test pads on the application board design for the following purposes:

• Checking the connection between the LE940B6 itself and the application

• Testing the performance of the module by connecting it with an external computer

Depending on the customer application, these test pads include, but are not limited to the

following signals:

• TXD

• RXD

• ON_OFF_N

• SHUTDOWN_N

• RESET_N

• GND

• VBATT

• VAUX/PWRMON

• TXD_AUX

• RXD_AUX

• USB_VBUS

• USB_D+

• USB_D-

• Signals for analysis

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

92 of 104

11.2. Bypass Capacitor on Power Supplies

When a sudden voltage step is asserted to or a cut from the power supplies, the steep transition

causes some reactions such as overshoot and undershoot. This abrupt voltage transition can

affect the device causing it to not operate or to malfunction.

Bypass capacitors are needed to alleviate this behavior. The behavior can appear differently

depending on the various applications. Customers must pay special attention to this issue when

they design their application board.

The length and width of the power lines must be considered carefully and the capacitance of the

capacitors must be selected accordingly.

The capacitor will also prevent ripple of the power supplies and the switching noise caused in

TDMA systems.

Especially, a suitable bypass capacitor must be mounted on the following lines on the application

board:

• VBATT & VBATT_PA (Pads AP17,AP19,AR18,AR20,AS17,AS19,AT18,AU17,AU19,AT20)

Recommended values are:

• 100 uF for VBATT & VBATT_PA

Customers must still consider that the capacitance mainly depends on the conditions of their

application board.

Generally, more capacitance is required when the power line is longer.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

93 of 104

11.3. SIM Interface

This section presents the recommended schematics for the design of SIM interfaces on the

application boards. The LE940B6 supports two external SIM interfaces.

11.3.1. SIM Schematic Example

Figure 27 illustrates in particular how to design the application side, and what values the

components should have.

Figure 27: SIM Schematics

NOTE:

An external pull-up resistor on SIMIO is not required.

The LE940B6 module contains an internal pull-up resistor on SIMIO.

Table 39 lists the values of C1 to be adopted with the LE940B6 product:

Table 39: SIM Interface – C1 Range

Product P/N C1 Range (nF)

LE940B6 100 nF

Refer to the following document for details:

• Ref 4: SIM Integration Design Guide

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

94 of 104

11.4. EMC Recommendations

All LE940B6 signals are provided with some EMC protection. Nevertheless, the accepted level

differs according to the specific pin. Table 40 lists the characteristics.

Table 40: EMC Recommendations

Pad Signal I/O

Function Contact Air

Antenna

AD1, AU9 Antenna

pads

I/O

Antenna pads ± 4 KV ± 8 KV

All other pins have the following characteristics:

• HBM JESD22-A114-B ± 1000 V

• CDM JESD22-C101-C ± 250 V

Warning:

Do not touch without proper electrostatic protective equipment. The product must be handled

with care, avoiding any contact with the pins because electrostatic discharge may damage the

product.

11.5. Download and Debug Port

This section provides recommendations for the design of the host system used to download or

upgrade the Telit software and to debug the LE940B6 module when it is already mounted on a

host system.

• For downloading or upgrading the Telit software

In the LE940B6 module, firmware updates by the host are only possible via USB and not via

UART.

So even if USB interface is not used, it is still highly recommended to place an optional USB

connector on the application board.At the minimum, test points of the USB signals are

required to enable SW update.

• For debugging of the LE940B6 module

USB, Auxiliary UART and JTAG interfaces can be used for debugging the LE940B6 module.

Even if USB or JTAG are not used for debugging, it is recommended to have at least the

Auxiliary UART pins exposed to outside for debugging purposes.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

95 of 104

11.6. Antenna Detection

The LE940B6 module provides an antenna detection application.

Many automotive applications require to detect if the antenna is shorted to ground or the battery

of the vehicle for fault tracing. Basically, antenna detection is performed by means of its DC

characteristics, splitting the DC and RF paths.

Refer to Telit 80000NT10002a - Antenna Detection Application Note.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

96 of 104

12. Packing System

The LE940B6 module is packed on trays.

The tray is JEDEC compliant, injection molded antistatic Modified Polyphenylene ether (MPPO). It

has good thermal characteristics and can withstand the standard baking temperature of up to

125°C, thereby avoiding the need of handling the modules if baking is required. The trays are

rigid, thus providing mechanical protection against transport stress. In addition, they are re-

usable and so environmentally sustainable.

There are 2 (two) antistatic rubber bands that enclose each envelope.

The carton box is rigid, thus offering mechanical protection. The carton box has one flap across

the entire top surface. It is sealed with tape along the edges of the box.

Table 41: Tray Packing

Modules per

Tray

Trays per

Envelope

Modules per

Envelope

Envelopes per

Carton Box

Modules per

Box

21 5+ 1 empty 105 4 420

Table 42: Packing Quantities

Order Type Quantity

Minimum Order Quantity (MOQ) 21

Standard Packing Quantity (SPQ) 420

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

97 of 104

Each tray contains 24 modules as shown in Figure 28.

Figure 28: Tray Packing

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

98 of 104

12.1. Tray Drawing

The Telit LE940B6 is packaged on trays. Each tray contains 21 pieces with the following

dimensions:

Figure 29: Tray Drawing

Warning:

These trays can withstand a maximum temperature of 125°C

12.2. Moisture Sensitivity

The LE940B6 module is a Moisture Sensitive Device Level 3, in accordance with standard

IPC/JEDEC J-STD-020. Observe all of the requirements for using this kind of components.

Calculated shelf life in sealed bag: 4 months at <40°C and <90% relative humidity (RH).

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

99 of 104

13. Conformity Assessment Issues

13.1. FCC/IC Regulatory Notices

Manual Information to the End User

The OEM integrator has to be aware not to provide information to the end user regarding

how to install or remove this RF module in the user’s manual of the end product which

integrates this module. The end user manual shall include all required regulatory

information/warning as show in this manual.

CAN ICES-3(B)/ NMB-3(B)

Federal Communication Commission Interference Statement

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two

conditions: (1) This device may not cause harmful interference, and (2) this device must

accept any interference received, including interference that may cause undesired operation.

This device complies with Industry Canada’s licence-exempt RSSs. Operation is subject to the

following two conditions:

(1) This device may not cause interference; and

(2) This device must accept any interference, including interference that may cause undesired

operation of the device.

Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux appareils radio

exempts de licence. L'exploitation est autorisée aux deux conditions suivantes:

(1) l'appareil ne doit pas produire de brouillage, et

(2) l'utilisateur de l'appareil doit accepter tout brouillage radioélectrique subi, même si le

brouillage est susceptible d'en compromettre le fonctionnement."

This equipment has been tested and found to comply with the limits for a Class B digital

device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable

protection against harmful interference in a residential installation. This equipment

generates, uses and can radiate radio frequency energy and, if not installed and used in

accordance with the instructions, may cause harmful interference to radio communications.

However, there is no guarantee that interference will not occur in a particular installation. If

this equipment does cause harmful interference to radio or television reception, which can be

determined by turning the equipment off and on, the user is encouraged to try to correct the

interference by one of the following measures:

- Reorient or relocate the receiving antenna.

- Increase the separation between the equipment and receiver.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

100 of 104

- Connect the equipment into an outlet on a circuit different from that to which the receiver is

connected.

- Consult the dealer or an experienced radio/TV technician for help.

Any changes or modifications not expressly approved by the party responsible for compliance

could void the user's authority to operate this equipment. This transmitter must not be co-

located or operating in conjunction with any other antenna or transmitter.

Radiation Exposure Statement

This equipment complies with FCC/IC radiation exposure limits set forth for an uncontrolled

environment. This equipment should be installed and operated with minimum distance 20 cm

between the radiator & your body.

End Product Labeling

When the module is installed in the host device, the FCC/IC ID label must be visible through a

window on the final device or it must be visible when an access panel, door or cover is easily

re-moved. If not, a second label must be placed on the outside of the final device that

contains the following text: “Contains FCC ID: RI7LE940B6NA”, “Contains IC: 5131A-

LE940B6NA.” The grantee's FCC/IC ID can be used only when all FCC/IC compliance

requirements are met.

This device is intended only for OEM integrators under the following conditions:

(1) The antenna must be installed such that 20 cm is maintained between the antenna and

users,

(2) The transmitter module may not be co-located with any other transmitter or antenna.

(3) To comply with FCC/IC regulations limiting both maximum RF output power and human

exposure to RF radiation, the maximum antenna gain including cable loss in a mobile

exposure condition must not exceed:

3.0 dBi in Cellular band

3.5 dBi in PCS band

3.5 dBi in AWS band

3.0 dBi in 700 MHz band

4.0 dBi in 2500MHz band

In the event that these conditions cannot be met (for example certain laptop configurations

or co-location with another transmitter), then the FCC/IC authorization is no longer

considered valid and the FCC/IC ID cannot be used on the final product. In these

circumstances, the OEM integrator will be responsible for re-evaluating the end product

(including the transmitter) and obtaining a separate FCC/IC authorization.

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

101 of 104

14. Safety Recommendations

READ CAREFULLY

Be sure that the use of this product is allowed in your country and in the environment required.

The use of this product may be dangerous and must be avoided in the following areas:

• Where it can interfere with other electronic devices in environments such as hospitals,

airports, aircrafts, etc.

• Where there is risk of explosion, such as gasoline stations, oil refineries, etc.

It is the responsibility of the user to enforce the country regulations and the specific environment

regulations.

Do not disassemble the product; any mark of tampering will compromise the warranty validity.

We recommend following the instructions of the hardware user guides for correct wiring of the

product. The product must be supplied with a stabilized voltage source and the wiring conform to

the security and fire prevention regulations.

The product must be handled with care, avoiding any contact with the pins because electrostatic

discharges may damage the product itself. The same caution must be taken for the SIM, checking

carefully the instructions for its use. Do not insert or remove the SIM when the product is in

power saving mode.

The system integrator is responsible for the functioning of the final product; therefore, care must

be taken of the external components of the module, as well as of any project or installation issue,

because of the risk of disturbing the cellular network or external devices or having any impact on

safety. Should there be any doubt, refer to the technical documentation and the regulations in

force.

Every module must be equipped with a proper antenna with the specified characteristics. The

antenna must be installed with care to avoid any interference with other electronic devices and

must be installed with the guarantee of a minimum 20 cm distance from a human body. If this

requirement cannot be satisfied, the system integrator must assess the final product against the

SAR regulation.

The European Community provides some Directives for electronic equipment introduced on the

market. All the relevant information is available on the European Community website:

http://europa.eu.int/comm/enterprise/rtte/dir99-5.htm

The text of the Directive 99/05 regarding telecommunication equipment is available, while the

applicable Directives (Low Voltage and EMC) are available at:

http://europa.eu.int/comm/enterprise/rtte/dir99-5.htm

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

102 of 104

15. Document History

Table 43: Document Revision History

Revision Date Changes

Rev. 1.8 2017-03-10

Sec. 5.1: Added Note

Sec. 5.3: Added Note

Sec. 6.1: Updated table 21 LE940B6 Current Consumption

Sec. 7.5: Added new sub chapter

Sec. 13: Added Conformity Assessment Issues

Rev. 1.7 2017-01-25

Sec. 5: Figures and charts revised

Sec. 6: Current consumption table updated

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

103 of 104

Revision Date Changes

v. 1.6 2016-11-15

Official Release

Sec. 2.7: Updated the Mechanical Specifications

Sec. 3.1: Added VPP pin for eFuse

Sections 3.1, 3.3, 4.3.6, 8: SD / MMC interfaces were deleted - they

are not supported by the chipset vendor.

Sec. 5: Updated the specifications and charts of Hardware

Commands (Boot-up/Shutdown time, On/Shutdown key hold

time)

Sec. 5.1: Updated the Power on Hold time.

Sec. 5.3.2: Updated the section of Hardware Shutdown

Sec. 5.3.3: Updated the Unconditional reset Hold time.

Sec. 6.1: Updated Table 21 – Current Consumption in various

modes

Sec. 6.2.2: Updated the Thermal Design Guidelines

Sec. 8.1: USB 3.0 interface is deleted - it is not supported by the

chipset vendor.

Sec. 8.3.3: WiFi (SDIO) is deleted - it is not supported by the

chipset vendor.

Sec. 8.6: Table 35 (Additional GPIO) is deleted - it is not supported

by the chipset vendor.

Sec. 9.7: eFuse section was added.

Sec. 11.4: Updated the EMC Recommendations

LE940B6 Hardware User Guide

1VV0301331 Rev. 1.8 - 2017-03-15

Telit Confidential Information, provided under NDA Page

104 of 104

Revision Date Changes

Rev. 1.5 2016-09-20

(Interim version)

Page 2, Table 1: Updated the Applicability table

Sec. 2: Updated the General Product Description

Sec. 2.5.1, 2.5.2: Updated the RF bands tables

Sec. 3.1: Updated the pin description in the Pin-out table

Sec. 4.3: Added tables of logic level specifications

Sec. 5: Updated the Turning On and Off trigger times, figures and

flow charts

Sec. 6.1: Added Table 20 - Power Supply Requirements

Sec. 8: Gathered the description of all hardware interfaces into

this section

Sec. 8.1: Updated note and figure for USB

Sec: 8.2: Various updates about the Serial Ports

Sec. 8.4: Updates about the Ethernet interface

Sec. 8.6: Updated the GPIO drive strength

Sec 11.5: Updated the Download and Debug Port section

Sec 12: Updated Packing System information

Rev. 1.3 2016-06-22

(Interim version)

Sec. 2.4.1: The Storage Temperature range is –40°C ~ +95°C

Sec. 3.1: Corrected and Updated the Pin out table

(Added GPIO_11/12, MIC_BIAS, VRTC, Removed GPIO_23/24)

Sec. 4: Added electrical specifications

Sec. 9.4.1: Modified the ADC table

Sec. 11.4: Added ESD specifications

Preliminary

2016-03-15

First issue

Telit Communications S p A LE940B6NA LE940B6-NA User Manual

Telit Communications S.p.A. LE940B6-NA

User Manual

Navigation menu

Namespaces

Views

Navigation