Neoway Technology 1232 GPRS Module User Manual

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Neo_M680
Hardware User Guide
Version 1.0
Let's enjoy the wireless life
Neo_M680 Hardware User Guide
V1.0
Copyright
Copyright © 2008 Neoway Technology
All rights reserved.
is a trade mark of Neoway Technology Co., Ltd.
Notice
This document is intended for the customer engineers.
This document is subject to change without any notice.
No responsibility is assumed by Neoway Technology for the use of this document.
Neoway Technology always provides the best supports.
For pricing, delivery, and ordering information please contact:
Sales@neoway.com.cn
For any technical support requests please contact:
Support@neoway.com.cn
For further information please visit:
http://www.neoway.com.cn
Copyright Neoway Techlology Co., Ltd.
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Neo_M680 Hardware User Guide
V1.0
Contents
Copyright ............................................................................................................................................ 2
1.
Introduction ................................................................................................................................ 6
2.
General Description ................................................................................................................... 6
3.
Simplified Block Diagram ......................................................................................................... 6
4.
Key Features ............................................................................................................................... 7
5.
Product Specifications ............................................................................................................... 8
6.
5.1
Variants ................................................................................................................................. 8
5.2
Dimension & Package........................................................................................................... 8
5.3
Pin Description...................................................................................................................... 9
5.4
PCB foot print ..................................................................................................................... 12
Application Interface ............................................................................................................... 13
6.1 Power Supply Requirements ................................................................................................ 13
6.2
6.3
6.4
7.
6.1.1
Power Supply Basic Design Rules ........................................................................ 13
6.1.2
Extended Design Rules for Power Supply: ........................................................... 15
ON/OFF Procedure ............................................................................................................. 17
6.2.1
Turning on the module: ......................................................................................... 18
6.2.2
Turning off the module: ........................................................................................ 18
6.2.3
RESET .................................................................................................................. 19
6.2.4
VMC ..................................................................................................................... 19
UART .................................................................................................................................. 20
6.3.1
Basic Descriptions of UART ................................................................................. 20
6.3.2
Level Translators for UART.................................................................................. 20
Sleep mode .......................................................................................................................... 22
6.4.1
DTR....................................................................................................................... 22
6.4.2
RING ..................................................................................................................... 23
6.5
SIM interface ...................................................................................................................... 23
6.6
Running LED Indicator ....................................................................................................... 25
6.7
Audio Interface ................................................................................................................... 26
6.8
Antenna Interface ................................................................................................................ 28
Mounting the Module onto the Application Board ............................................................... 30
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Neo_M680 Hardware User Guide
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8.
Package ..................................................................................................................................... 30
9.
Terms and Abbreviations......................................................................................................... 31
Copyright Neoway Techlology Co., Ltd.
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Neo_M680 Hardware User Guide
V1.0
Document History
Revision History
Version
Remarks
Date Issue
V1.0
Initial Version
2013-9
Copyright Neoway Techlology Co., Ltd.
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Neo_M680 Hardware User Guide
V1.0
1. Introduction
This document describes the hardware features of M680, and guides for the relevant
application design.
2. General Description
With the ultra-compact design, M680 is intended to be used in a wide range of applications,
including industrial and consumer devices. M680 is a GSM/GPRS module with EDGE of
downlink. It features with voice, SMS, and data services.
3. Simplified Block Diagram
PA
RF
Section
SIM
Power
Manager
Application Interface
Audio
Section
FLASH
Baseband
Controller
I2C
UART x 2
ADC/PWM
Figure 1 M680 Block Diagram
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Neo_M680 Hardware User Guide
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4. Key Features
Table 1 M680 Key Features
Feature
Frequency Bands
Implementation
850/900/1800/1900 MHz quad-band
Compliant with GSM/GPRS Phase2/2+
Sensitivity
Transmit Power
< -107dBm
850/900 Class4(2W)
1800/1900 Class1(1W)
AT
GSM07.07
Extended AT commands
Audio CODEC
SMS
FR、EFR、HR、AMR
TEXT/PDU
Point-to-point / cell broadcast
DATA
GPRS: Class 12
Call forwarding（CFB, CFNA, CFU）
Supplementary Service
Call waiting & Call hold
Multiparty call
USSD
CPU
Open Resources
Interfaces
Operational Temperature
Operating Voltage
Peak Current
Power Consumption
Copyright Neoway Techlology Co., Ltd.
ARM7-EJ@260MHz, 32Mbits SRAM, 16~32Mbits Nor Flash
16Mbits RAM, 0.3~16Mbits Flash
UART x 2, I2C, SPI, ADC, PWM, GPIO
-40℃～+85℃
3.5V～4.2V（typical 3.9V）
Max 1.8A
< 2mA @DRX5 (Sleep mode)
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Neo_M680 Hardware User Guide
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5. Product Specifications
5.1 Variants
Variants
Frequencies
Packages
M680-QUAD-AA0/A00
850/900/1800/1900MHz Quad-band
71 Pin LCC
5.2 Dimension & Package
Physical Characteristics
Dimensions
15mm*18mm*2.1mm (Length*Width*Thickness)
Weight
2g
Package
71 Pin LCC
Figure 2 M680 Sketch
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5.3 Pin Description
Table2 M680 pin definition
M680
Pin
Signal
I/O
Function
Note
ON/OFF
DI
Switch the module on/off
Low level pulse triggered
SPKP
AO
Speaker output P
AO
SPKN
MICP0
AI
Speaker output N
MIC+
Use AT command to open and
0.9W@8Ω
MICN0
AI
MIC-
Vi ≤ 200mVpp
AO
Earpiece output L
Signal Ended Output. Can
drive a 16Ω/32Ω earpiece
directly.
Signal Ended Output. Can
drive a 16Ω/32Ω earpiece
directly.
Vi ≤ 200mVpp
EAR-L
EAR-R
AO
Earpiece output R
MICN1
AI
MIC-
Vi ≤ 200mVpp
MICP1
AI
MIC+
Vi ≤ 200mVpp
10
RECN
AO
Receiver output N
11
RECP
AO
Receiver output P
32Ω receiver output
12
Reserved
Reserved
13
Reserved
Reserved
14
Reserved
Reserved
15
Reserved
Reserved
16
Reserved
Reserved
17
Reserved
Reserved
18
PWR
19
GND
SIM_CLK
DO
GND
SIM clock
20
SIM_DATA
DIO
SIM data
5KΩ internal pull-up
21
SIM_RST
SIM reset
Prompted by module
22
VSIM
DO
PWR
SIM supply voltage
1.8/3.0V compatible.
23
DAISYNC
DO
Digital audio synchronization
24
DAIPCMIN
DI
Digital audio input
25
DAIPCMOUT
DO
Digital audio output
26
DAICLK
DO
Digital audio signal clock
27
Reserved
Reserved
28
Reserved
Reserved
29
GND
PWR
GND
30
BT_ANT
I/O
Antenna interface for BT
31
GND
PWR
GND
32
Reserved
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Connect 50Ω antenna
Reserved
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Neo_M680 Hardware User Guide
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33
Reserved
Reserved
34
Reserved
Reserved
35
Reserved
Reserved
36
VMC
PWR
Output 2.8V
37
DI
38
URXD
UTXD
Serial data input of module
Serial data output of module
39
Reserved
Reserved
40
41
Reserved
VRTC
PWR
Reserved
RTC power
42
DTR
DI
Data Terminal Ready
Can be used to control sleep
mode.
43
RING
DO
Output for RING indicator
Can be used to indicate an
incoming voice call or SMS.
44
LIGHT
DO
Status LED
2.8V/4mA output
Can drive a LED directly
45
Reset
DI
Reset input
Active low
46
PWR
GND
47
GND
GPRS_ANT
I/O
GPRS antenna interface
48
GND
PWR
GND
49
Reserved
Reserved
50
Reserved
Reserved
51
Reserved
Reserved
52
Reserved
Reserved
53
Reserved
Reserved
54
Reserved
Reserved
55
56
Reserved
ADC
AI
Reserved
ADC input
61
USB_DM
I/O
62
USB_DP
I/O
VBAT
PWR
Main power supply
3.5V~4.3V (typical 3.9V)
VBAT
PWR
Main power supply
3.5V~4.3V (typical 3.9V)
GND
PWR
GND
DO
Can be used to power the level
translators. Imax=50mA
2.8V, Imax=2mA
Connect 50Ω antenna
0V 60mS.
ON/OFF
VBAT
DI
Switch the module on/off
Main Power Supply
Low level pulse triggered.
PWR
3.5V~4.3V(typical 3.9V)
6.1.1 Power Supply Basic Design Rules
VBAT is the main power supply for internal base band and radio PA of the module, in a range of
3.5V-4.3V. A 3.9V voltage is preferable.
The performance of power supply issued, is a critical path to module’s performance and stability.
The GSM bursts can cause current peaks up to 1.8A, therefore large bypass capacitors are expected
to reduce voltage drops during the bursts. The biggest current occurs when the received signal is
very low. It’s very important to ensure that the voltage of supply rail never drops below 3.5V
while any burst occurs.
Figure 4 shows how the GSM bursts and voltage drops.
Figure 5 shows how the capacitor helps to improve peak current performance:
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Figure 4 Burst Caused Current Peaks and Voltage Drops
Figure 5 Test Circuit and Peak Current
Results may vary depending on the ESR of capacitors, and the impedance of power source.

A low ESR 1000uF aluminum capacitor for C1 can be selected. As an alternative, a 470uF
tantalum capacitor is also suited. In case of Li-Ion cell battery used, 220uF or even 100uF
tantalum capacitor may be applicable because of the battery’s low internal impedance and the
ability to provide high transient current.

Use a low impedance power source, and keep the resistance of the power supply lines as low as
possible.
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
The power source should be able to output an average current greater than 1A.

Some small capacitors, with values of 0.1uF, 100pF, 33pF, placed close to the module’s power
pin, are very helpful to suppress high frequency disturbances.

The voltage range of power supply must never be exceeded. Over-voltage can even destroy the
module permanently.

Ensure the trace for VBAT to be wide enough, in order to pass the current peaks without
significant voltage drops. The width of 2mm is preferable.
6.1.2 Extended Design Rules for Power Supply:
6.1.2.1 Power Control
A controlled power supply is preferable if used in harsh conditions. RESET pin may be not
functioning under strong disturbance. The output enable pin of LDO or DC/DC chipset could be
used for emergency power control of the module, as shown in Figure 6.
Figure 6 Using LDO’s enable pin for emergency power control
The alternative way is to use a P-MOSFET to control the module’s power, as shown in Figure 7. The
GPRS_EN signal is routed to host GPIO, controlling the ON/OFF of the P-MOSFET. The host can
cut off and then switch on the power supply in case of abnormal conditions, such as no response
from the module or the disconnection of GPRS.
Copyright Neoway Techlology Co., Ltd.
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Figure 7 Using PMOS for power control
Q2 is for eliminating the need for a high enough voltage level of the host GPIO. In case that the
GPIO can output a high voltage greater than VDD3V9 - |VGS(th)|, where VGS(th) is the Gate Threshold
Voltage, Q2 is not needed.
Reference components:
Q1: IRML6401
Q2: MMBT3904
C4: 470uF tantalum capacitor rated at 6.3V; or 1000uF aluminum capacitor.
It’s strongly recommended to place a TVS diode on VBAT to ground, in order to absorb the power
surges subjected. The SMAJ5.0A from Vishay can be as a choice.
6.1.2.2
Power Separating
As described in section 6.1.1, the GSM device works in burst mode generating voltage drops on
power supply. And furthermore this results in a 217Hz TDD noise through power (One of the way
generating noise. Another way is through RF radiation). Analog parts, especially the audio circuits,
are subjected to this noise, known as a “buzz noise” in GSM systems. To prevent other parts from
being affected, it’s better to use separated power supplies. The module shall be supplied by an
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Neo_M680 Hardware User Guide
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independent power, like a DC/DC or LDO.
The inductor used in Reference Design (b), should be a power inductor and have a very low
resistance. The value of 10uH, with average current ability>1.2A and low DC resistance, is
recommended.
Figure 8 Using separated power supply for module
Never use a diode to make the drop voltage between a higher input and module power. It will
obviously decrease the module performances, or result in unexpected restarts, due to the forward
voltage of diode will vary greatly in different temperature and current.
6.1.2.3 EMC Considerations for Power Supply
Place transient overvoltage protection components like TVS diode on power supply, to absorb the
power surges. SMAJ5.0A could be a choice.
6.1.2.4 Power-on Sequence
Prior to turning on the module, turn on the host MCU and finish the UART initialization. Otherwise
conflictions may occur during initialization, due to unstable conditions.
6.2 ON/OFF Procedure
ON/OFF is a low level pulse active input, used to turn on or off the module.
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Figure 9 Turning on /off the module using ON/OFF
6.2.1 Turning on the module:
While the module is off, drive the ON/OFF pin to ground for at least 600mS (800mS is
recommended) and then release, the module will start. An unsolicited message will be sent to host
through AT port (“+EIND: 1”), indicating the powering up of the module and the AT commands can
respond.
It’s recommended to drive the ON/OFF to low before applying the VBAT to module. 300mS
(400mS is recommended) later from the VBAT applied, release the ON/OFF. Therefore the module
starts up. The simplest way to power on the module, is to directly tie the ON/OFF to ground, issuing
to an auto-power-on feature.
After the module is operating, keep ON/OFF being high level.
6.2.2 Turning off the module:
While the module is on, drive the ON/OFF pin to ground for at least 500mS and then release, the
module will try to detach to network and normally 1 second later it will shut down. Another
approach to turn off the module is with AT command.
Figure 10 shows a reference circuits for ON/OFF control with inverted control logic.
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Figure 10 Reference circuit for ON/OFF control
Reference Components:
Q1: MMBT3904, or to use digital transistor with bias resistors built in, like DTC123/114
The combination of R3 and R4, should limit the high voltage of ON/OFF less than 3.0V.
Note:

If the host itself is not initialized before turning on the module, some abnormal conditions on
IO or UART may affect the power on procedure.

The better way to rescue the module from abnormal condition, is to apply a power OFF-ON
procedure, rather than using the ON/OFF control signal. In fact ON/OFF signal is
software-dependent.
6.2.3 RESET
Pull the Reset signal to low level for at least 60mS to reset the module. A pull-up resistor is
internally included. Reset pin can be left open if not used.
6.2.4 VMC
VMC is provided to power the level translators, with a 2.8V / 5mA output.
VMC can also be used to monitor the on/off state of module. It outputs 2.8V high level while the
module is on, and low level while the module is off.
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6.3 UART
6.3.1 Basic Descriptions of UART
Signal
I/O
Table 4 UART
Function
URXD1
UTXD1
DI
DO
Serial input of module
Serial output of module
DTR
DI
Signal for controlling sleep mode
RING
DO
Ringing output
Note
UART1 is for AT commands, data sending/receiving, firmware updating, etc.
As a DCE device, the module is connected to DTE as shown in Figure 11.
Supported baud rates are 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400bps, and the
default is 115200.
Figure 11 Connection between DCE (module) and DTE
The UART of M680 works at 2.8V CMOS logic level. The voltages for input high level should not
exceed 3.0V.
6.3.2 Level Translators for UART
If the UART is interfacing with a MCU that has 3.3V logic levels, resistors should be connected in
series with the signals.
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Figure 12 Interfacing with 3.3V logic levels of MCU
If the UART is interfacing with a MCU that has 5V logic levels, general level translators are
required, for both inputs and outputs. As shown in Figure 13.
Figure 13 Interfacing with 5V logic levels of MCU
Reference components:
R2: 2K-10K. The higher rate the UART works at, the smaller value used
R3: 4.7K-10K. The higher rate the UART works at, the smaller value used
Q1: MMBT3904 or MMBT2222. High-speed transistors preferred.
Used for 5V logic -> 2.8V logic:
While this circuit used between MCU TXD and module URXD1, the INPUT signal is connected to
MCU TXD, and OUTPUT connected to module URXD1. VCC_IN powered from 5V and
VCC_OUT powered from 2.8V (module’s VMC can be used). This applies to DTR control as well.
Used for 2.8V logic -> 5V logic:
It can be used between module UTXD1 and MCU RXD as well, with INPUT connected to module
UTXD1, and OUTPUT connected to MCU RXD. VCC_IN powered from 2.8V (module’s VMC)
and VCC_OUT powered from 5V. This applies to RING signal as well.
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Note:
Avoid sparks and glitches on UART signals while the module is in a turning on procedure.
Avoid sending any data to UART during the beginning of 2 seconds after the module being turned
on.
6.4 Sleep mode
6.4.1 DTR
Generally DTR is used for sleep mode control. For details, see AT commands manual. Based on the
setting of the selected mode, pulling DTR low will bring the module into relevant power saving
mode. Working in this mode, the power consumption is around 2mA, depending on the DRX setting
of network.
In sleep mode, the module can also respond to the incoming call, SMS, and GPRS data. The host
MCU can also control the module to exit sleep mode by controlling DTR.
The controlling of sleep mode:
1) Keep DTR high in normal working mode. Activate the sleep mode by using the AT command
AT+ENPWRSAVE=1.
2) Pull DTR low, the module will enter sleep mode, but only after process and pending data
finished.
3) UART is not available in sleep mode.
4) In sleep mode, the module can be woken up by the events of incoming voice call, received data,
or SMS. Meanwhile the module will send out the unsolicited messages by the interface of RING
or UART.
Upon receipt of the unsolicited messages, the host MCU should pull DTR high firstly, otherwise
the module will resume sleep mode shortly. And then the host MCU can process the voice call,
received data, or SMS. After processing is finished, pull DTR low again to put the module into
Copyright Neoway Techlology Co., Ltd.
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sleep mode.
5) Pull DTR high, the module will exit from sleep mode actively, and furthermore enable the
UART. Thus the voice call, received data, or SMS can be processed through UART. After
processing finished pull it low again, to take the module back to sleep mode.
6.4.2 RING
1)
Once the incoming voice call, the module sends out “ring” message through UART and
meanwhile outputs 250mS low pulses at 4S period on RING signal. See Figure 14.
Figure 14 RING indicator for incoming call
2)
Upon receipt of SMS, the module outputs one 600mS low pulse. See Figure 15.
Figure 15 RING Indicator for SMS
6.5 SIM interface
Table 5 SIM Interface
Signal
I/O
VSIM
SIM_CLK
PWR
SIM_RST
SIM_DATA
DO
DO
DIO
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Function
SIM supply voltage
SIM clock
SIM reset
SIM data
Note
1.8/3.0V
Internal pull up
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Figure 16a Reference design of SIM interface
Pin1=VCC, Pin2=RST, Pin3=CLK, Pin4=GND, Pin5=VPP, Pin6=DATA
Figure 16b a sample of SIM card socket
Figure 16c the recommended ESD diode array
M680 SIM interface is 3V/1.8V compatible. VSIM is for SIM power and can supply a 30mA
current.
SIM_DATA is internally pulled up with a 5KΩ resistor. External pull-up resistor is not needed.
SIM_CLK can work at several frequencies, but at 3.25MHz typically.
ESD protectors, such as ESD diodes or ESD Varistors, are recommended on the SIM signals,
especially in automotive electronics or other applications with badly ESD. The total equivalent
capacitance on any SIM signal, include the junction capacitance of the ESD diode and the distributed
capacitance of PCB trace, can’t be higher than 120pF.
If the SIM card is installed in a closed case without human touch or ESD, 22~33pF MLCC
capacitors can replace the ESD diodes for cost down.
SIM card is sensitive to GSM TDD noise and RF interference. So, the rule is very important in the
PCB design, listed as the following.
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☆ The antenna should be installed a long distance away from the SIM card and SIM card traces,
especially to the build-in antenna.
☆ The PCB traces of SIM should be as short as possible and shielded with GND copper.
☆ The ESD diodes or small capacitors should be closed to SIM card.
Note:
Small capacitors and the junction capacitance of the ESD diode are to avoid the interference from/to
antenna, ensuring the correct SIM access and good RF performance.
6.6 Running LED Indicator
Table 6 Running Indicator
Signal
I/O
Function
Note
BACK_LIGHT
DO
Running Status
Can drive a LED directly
The various blink behaviors of LED indicate different of module status.
It can output a 4mA current and 2.8V voltage, therefore a LED can be directly connected to this pin
with a resistor in series. For better luminance, drive the LED with a transistor instead, see Figure 17.
Figure 17 LED Indicator
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6.7 Audio Interface
Table 7 Audio Interface
Signal
I/O
Function
Note
SPKP
AO
Speaker output P
SPKN
MICP0
AO
AI
Speaker output N
MIC+ input
Use AT command to open
and 0.9W@8Ω
MICN0
AI
MIC- input
EAR-L
AO
Earpiece output L
Can drive a 16Ω/32Ω earpiece
directly
EAR-R
AO
Earpiece output R
Can drive a 16Ω/32Ω earpiece
directly
MICN1
AI
MIC-
MICP1
AI
MIC+
RECN
AO
Receiver output N
32Ω receiver output
RECP
AO
Receiver output P
32Ω receiver output
Vpp≤ 200mV
Vpp≤ 200mVpp
For reference audio interface see Figure 18. The peak-peak voltage routed to MIC+/MIC- should not
exceed 200mV. AGC circuit is integrated inside the module. Electret microphone is suited.
Figure 18 Reference design of microphone interface
A bias voltage for microphone is provided through MICP and MICN, as shown in Figure 19. But if
an amplifier is used between the microphone and module, capacitors like C1 and C2, should be
placed between the outputs of amplifier and module, to block the bias voltage.
For a peak-peak voltage greater than 200mV, an attenuation circuit comprised of R1-R4 should be
used.
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Figure 19 Reference design for MIC interface
Figure 20 Reference design for Ear interface
Figure 20 shows a reference design for earpiece interface. A 16Ω/32Ω earpiece can be directly
driven by the module. To pass the low frequency audio, use large capacitors for C1 and C2.
If an external amplifier is used for driving the speakers, 1uF~4.7uF coupling capacitors should be
used to block the DC voltage, as shown in Figure 21.
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Figure 21 Using capacitors to couple audio outputs
As the description of TDD noise before, the GSM radio frequency is modulated at 217Hz. The
217Hz and its derivative frequency is well within audio band, therefore a TDD noise often affect the
audio performance through power and air. Some small capacitors between 27pF-100pF and ferrite
beads, placed on the audio path can attenuate TDD noise.
For Suppressing the TDD noise, differential audio interface is preferable. The PCB trace of audio
signal should be routed as differential line.
In particular, the microphone interface is a pair of small signal, peak-peak voltage <200mV, must
comply the rule of differential line. The microphone interface should be routed as short as possible.
6.8 Antenna Interface
A 50Ω antenna is required. VSWR < 1.5. The antenna should be well matched to achieve best
performance. It should be installed far away from high speed logic circuits, DC/DC power, or any
other strong disturbing sources.
ESD protection is built in module. For special ESD protection, a ESD diode can be placed close to
the antenna. But ensure to use a low junction capacitance one. The junction capacitance should be
less than 0.5pF, otherwise the RF signal will be attenuated. RCLAMP0521P from Semtech, or
ESD5V3U1U from Infineon, can be used here. See Figure 22.
The trace between the antenna pad of module and the antenna connector, should have a 50Ω
characteristic impedance, and be as short as possible. The trace should be surrounded by ground
copper. Place plenty of via holes to connect this ground copper to main ground plane, at the copper
edge.
Copyright Neoway Techlology Co., Ltd.
Page 28 of 31
Neo_M680 Hardware User Guide
V1.0
If the trace between the module and connector has to be longer, or built-in antenna is used, a π-type
matching circuit should be needed, as shown in Figure 22. The types and values of C1, L1, and L2
should be verified by testing using network analyzer instrument. If the characteristic impedance is
well matched, and VSWR requirement is met, just use a 0Ω resistor for C1 and leave L1, L2
un-installed.
Avoid any other traces crossing the antenna trace on neighboring layer.
Figure 22 Reference design for antenna interface
Figure 23 Reference parameters for 50Ω trace on a 1.6mm double layer PCB
Copyright Neoway Techlology Co., Ltd.
Page 29 of 31
Neo_M680 Hardware User Guide
V1.0
This GND Pad
should be well
routed to ground
Antenna trace should be surrounded by
ground which is connected to main
ground plane with plenty of via holes.
The trace width and the space to ground
should be decided by calculating of 50Ω
impedance match.
Figure 24 Reference layout for antenna interface
7. Mounting the Module onto the Application Board
M680 is compatible with industrial standard reflow profile for lead-free SMT process.
The reflow profile is process dependent, so the following recommendation is just a start point
guideline:

Only one flow is supported.

Quality of the solder joint depends on the solder volume. Minimum of 0.15mm stencil thickness
is recommended.

Use bigger aperture size of the stencil than actual pad size.

Use a low-residue, no-clean type solder paste.
8. Package
M680 modules are packaged in sealed bags on delivery to guarantee a long shelf life. Package the
modules again in case of opening for any reasons.
If exposed in air for more than 48 hours at conditions not worse than 30°C/60% RH, a baking
procedure should be done before SMT. Or, if the indication card shows humidity greater than 20%,
Copyright Neoway Techlology Co., Ltd.
Page 30 of 31
Neo_M680 Hardware User Guide
V1.0
the baking procedure is also required.
The baking should last for at least 24 hours at 90℃.
9. Terms and Abbreviations
ADC
Analog-Digital Converter
AGC
Automatic Gain Control
AMR
Acknowledged multirate (speech coder)
CSD
Circuit Switched Data
CPU
Central Processing Unit
DCE
Data Communication Equipment
DTE
Data Terminal Equipment
DTR
Data Terminal Ready
EFR
Enhanced Full Rate
EMC
Electromagnetic Compatibility
EMI
Electro Magnetic Interference
ESD
Electronic Static Discharge
FR
Full Rate
GPRS
General Packet Radio Service
GSM
Global Standard for Mobile Communications
HR
Half Rate
IC
Integrated Circuit
IMEI
International Mobile Equipment Identity
LED
Light Emitting Diode
PCB
Printed Circuit Board
RAM
Random Access Memory
RF
Radio Frequency
SIM
Subscriber Identification Module
SMS
Short Message Service
SMT
Surface Mounted Technology
SRAM
Static Random Access Memory
TDMA
Time Division Multiple Access
UART
Universal asynchronous receiver-transmitter
Varistor
Voltage Dependent Resistor
VSWR
Voltage Standing Wave Ratio
Copyright Neoway Techlology Co., Ltd.
Page 31 of 31
ESD protection
EADS requires that the M680 GPRS Module's service points have sufficient ESD protection
(against static electricity) when servicing the product. Any product which has its covers removed
must be handled with ESD protection. To replace the covers, ESD protection must be applied. All
electronic parts of the product are susceptible to ESD.
All ESD‐sensitive parts must be packed in metallized protective bags during shipping and handling
outside any ESD Protected Area (EPA).
Every repair action involving opening the product or handling the product components must be
done under ESDprotection.
ESD‐protected spare part packages MUST NOT be opened/closed outside of an ESD Protected
Area.
EU Regulatory Conformance
As certified by the qualified laboratory, the product is in compliance with the essential
requirements and other relevant provisions of the Directive 1999/5/EC. Please note that the
above information is applicable to EU countries only.
Antenna Installation: Install the GPRS module antenna at least 20 cm away from your body, in
accordance with the requirements of the antenna manufacturer/supplier.
FCC Statment
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.
Any Changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equipment.
Note: 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, 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 equipment does cause harmful interference to
radio or television reception,
—Reorient or relocate the receiving antenna.
—Increase the separation between the equipment and receiver.
—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.
Label of The End Product
The final end product must be labeled in a visible are with the following “Contains TX FCC
ID:PJ7‐1232”.The FCC part 15.19 statement below has to also be available on the label:This device
complies with Part 15 of 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.
To comply with FCC regulations limiting both maximum RF output power and human exposure to
RF radiation,the maximum antenna gain including cable loss in a mobile‐only exposure condition
must not exceed 1dBi for both GSM850 and PCS1900.
A user manual with the end product must clearly indicate the operating requirements and
conditions that must be observed to ensure compliance with current FCC RF exposure guidelines.
The end product with an embedded M680 GPRS Module may also need to pass the FCC Part 15
unintentional emission testing requirements and be properly authorized per FCC Part 15.
Note:If this module is intended for use in a portable device,you are responsible for separate
approval to satify the SAR requirements of FCC Part 2.1093.

---

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