Huawei 01 正文 Module Power Supply Design Guide V100R001 02

HUAWEI Module Power Supply Design Guide-V100R001_02

HUAWEI_Module_Power_Supply_Design_Guide-V100R001_02

HUAWEI_Power_Supply_Guide

HUAWEI Module Power Supply Design Guide-(V100R001_02, English)

2015-02-27

使用手册: Huawei

Open the PDF directly: View PDF .
Page Count: 20

Revision History
Contents
1 Overview
2 Power Supply Requirements
3 Power Supply Design Requirements
4 External Power Supply Circuits
5 Recommendations for the Layout and Routing of External Power Supply Circuits
6 Acronyms and Abbreviations

HUAWEI Module

Power Supply Design Guide

Issue

Date

2014-11-07

No part of this manual may be reproduced or transmitted in any form or by any means without prior written

consent of Huawei Technologies Co., Ltd. and its affiliates ("Huawei").

The product described in this manual may include copyrighted software of Huawei and possible licensors.

Customers shall not in any manner reproduce, distribute, modify, decompile, disassemble, decrypt, extract,

reverse engineer, lease, assign, or sublicense the said software, unless such restrictions are prohibited by

applicable laws or such actions are approved by respective copyright holders.

Trademarks and Permissions

, , and are trademarks or registered trademarks of Huawei Technologies Co., Ltd.

LTE is a trade mark of ETSI.

Other trademarks, product, service and company names mentioned may be the property of their respective

owners.

Notice

Some features of the product and its accessories described herein rely on the software installed, capacities

and settings of local network, and therefore may not be activated or may be limited by local network

operators or network service providers.

Thus, the descriptions herein may not exactly match the product or its accessories which you purchase.

Huawei reserves the right to change or modify any information or specifications contained in this manual

without prior notice and without any liability.

DISCLAIMER

ALL CONTENTS OF THIS MANUAL ARE PROVIDED “AS IS”. EXCEPT AS REQUIRED BY APPLICABLE

LAWS, NO WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT

LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

PURPOSE, ARE MADE IN RELATION TO THE ACCURACY, RELIABILITY OR CONTENTS OF THIS

MANUAL.

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT SHALL HUAWEI BE

LIABLE FOR ANY SPECIAL, INCIDENTAL, INDIRECT, OR CONSEQUENTIAL DAMAGES, OR LOSS OF

PROFITS, BUSINESS, REVENUE, DATA, GOODWILL SAVINGS OR ANTICIPATED SAVINGS

REGARDLESS OF WHETHER SUCH LOSSES ARE FORSEEABLE OR NOT.

THE MAXIMUM LIABILITY (THIS LIMITATION SHALL NOT APPLY TO LIABILITY FOR PERSONAL

INJURY TO THE EXTENT APPLICABLE LAW PROHIBITS SUCH A LIMITATION) OF HUAWEI ARISING

FROM THE USE OF THE PRODUCT DESCRIBED IN THIS MANUAL SHALL BE LIMITED TO THE

AMOUNT PAID BY CUSTOMERS FOR THE PURCHASE OF THIS PRODUCT.

Import and Export Regulations

Customers shall comply with all applicable export or import laws and regulations and be responsible to

obtain all necessary governmental permits and licenses in order to export, re-export or import the product

mentioned in this manual including the software and technical data therein.

To better understand how we protect your personal information, please see the privacy policy at

http://consumer.huawei.com/privacy-policy.

HUAWEI Module Power Supply Design Guide

About This Document

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

About This Document

Revision History

Document

Version

Date

Chapter

Descriptions

2011-10-12

Creation

2014-11-07

2.1

Updated the power pin of HUAWEI

modules

2.3

Updated power supply requirements in

not 2G mode

3.3

Added the type of the recommend

capacitor with high capacity

4.4

Added the type of the filtering capacitor

HUAWEI Module Power Supply Design Guide

Contents

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Contents

1 Overview ................................................................................................................................... 5

2 Power Supply Requirements .................................................................................................. 6

2.1 Power Pin Definition .................................................................................................................... 6

2.2 Power Supply Requirements in 2G Mode .................................................................................... 6

2.3 Power Supply Requirements in not 2G Mode............................................................................... 8

2.4 Power Consumption .................................................................................................................... 9

3 Power Supply Design Requirements .................................................................................. 10

3.1 Introduction to Peripheral Power Supplies ..................................................................................10

3.2 Reducing Internal Resistance .....................................................................................................10

3.3 Adding Energy Storage Capacitors ............................................................................................. 11

3.4 Improving Transient Response of the Power Supply IC ...............................................................14

4 External Power Supply Circuits ........................................................................................... 16

4.1 Choosing the Power Supply IC ...................................................................................................16

4.2 Power Supply Protection ............................................................................................................16

4.3 Power-on and Power-off Sequences ..........................................................................................17

4.4 Choosing the Filtering Capacitor .................................................................................................18

5 Recommendations for the Layout and Routing of External Power Supply Circuits .... 19

6 Acronyms and Abbreviations ............................................................................................... 20

HUAWEI Module Power Supply Design Guide

Overview

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

1 Overview

This document mainly describes the power supply design for Huawei modules. This

document also provides Huawei modules' requirements for power supplies, which

can be used as reference for designing power supplies for Huawei modules. This

document is composed of four chapters:

- Power Supply Requirements

- Power Supply Design Requirements

- External Power Supply Circuits

- Recommendations for the Layout and Routing of External Power Supply Circuits

HUAWEI Module Power Supply Design Guide

Power Supply Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

2 Power Supply Requirements

2.1 Power Pin Definition

Table 2-1 The power pin of HUAWEI modules

HUAWEI Modules

Power Pin Name

Power Supply Voltage

LGA modules

VBAT

3.3 V–4.2 V (typically 3.8 V)

LCC modules

VBAT

3.3 V–4.2 V (typically 3.8 V)

Mini PCIe modules

VCC_3V3

3.0 V–3.6 V (typically 3.3 V)

M.2 modules

3.3V

3.135 V–4.4 V (typically 3.3 V)

All power supply pins and ground pins must be connected.

2.2 Power Supply Requirements in 2G Mode

This section describes the electrical characteristics of Huawei modules operating in

2G mode. The power consumption of Huawei modules is related to their transmitted

power (the transmitted power is the power that a wireless terminal transmits to a

base station, also known as uplink power). The greater the transmitted power, the

higher the power consumption.

The Global System for Mobile Communications (GSM) uses time division multiple

access (TDMA). Using this method, Huawei modules transmit power only during the

time slots allocated by base stations. In the GSM, each transmission period is divided

into eight time slots and each time slot lasts 577 µs. Modules transmit power during

one of the eight time slots. Therefore, the transmission period is 4.615 ms and the

transmission time is 577 µs in each transmission period. This transmission mode of

GSM wireless terminals is called "burst". The power transmitted by Huawei modules

during the allocated time slots is dependent on the received signal strength. The

stronger the received signal strength (the signal strength of the base station), the less

the transmitted power. The weaker the received signal strength, the greater the

transmitted power. The maximum transmitted power is 33 dBm (GSM-900).

Figure 2-1 illustrates the power transmitting mode in GSM.

HUAWEI Module Power Supply Design Guide

Power Supply Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Figure 2-1 Power transmitting mode in GSM

577uS 577uS

577uS x 8 slot

4.61ms 4.61ms 4.61ms

Power

Max 33dBm

For general packet radio service (GPRS), the uplink transmission uses two or more

successive time slots, as illustrated in Figure 2-2 .

Figure 2-2 GPRS uplink transmission

577uS

577uS x 8 slot

4.61ms 4.61ms 4.61ms

Power

1.15ms

Max 30dBm

Because of the characteristics of TDMA used in GSM, Huawei modules' power

consumption changes periodically with bursts in accordance with the transmission

periods, as illustrated in Figure 2-3 .

HUAWEI Module Power Supply Design Guide

Power Supply Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Figure 2-3 Huawei modules' power consumption changes

577uS 577uS

577uS x 8 slot

4.61ms 4.61ms 4.61ms

Power

Max 33dBm

Current- Ibat

Voltage-Vbat

Peak current

Max 2.5A

Dropout voltage

We can see from Figure 2-3 that during transmission time slots, the power amplifier

(PA) of the module's GSM unit amplifies power for transmission. If the received signal

strength is weak, the transmitted power may reach 33 dBm, and the transient electric

current supplied to the module can reach 2.5 A (IBAT). As a result, the power supply

voltage may drop.

The power supply voltage may drop, if:

- The power supply does not have good transient response performance and its

output cannot reach 2 A–3 A within several milliseconds.

- The internal resistor of the power supply (that is, the output impedance of the

power interface) is great. When the current is great, the voltage on the resistor

reduces outside the range specified by the module.

At the end of a transmission time slot, the PA shuts down, and the electric current

and voltage recover until the next transmission time slot comes after 4.615 ms.

Therefore, Huawei modules operating in 2G mode must have good transient

response performance and small internal resistance to prevent voltage drop.

Considering the product cost and that Huawei modules can operate within a certain

range of voltages, the minimum voltage of the power supply after dropping should not

be less than the minimum voltage specified by the module.

2.3 Power Supply Requirements in not 2G Mode

WCDMA and FDD-LTE telecommunications use code division multiple access

(CDMA). Therefore, on these networks, the transmitted power is not related to the

time.

Figure 2-4 shows the transmitted power of a Huawei module operating on the

WCDMA and FDD-LTE network.

HUAWEI Module Power Supply Design Guide

Power Supply Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Figure 2-4 Transmitted power of the WCDMA and FDD-LTE system

time

Power

Max 24dBm

For Huawei modules operating on the WCDMA and FDD-LTE networks, when the

transmitted power reaches the maximum transmitted power, the required maximum

current from the power supply is approximately 1100 mA. Therefore, power supplies

with an average output of at least 1.5 A are required.

TD-SCDMA and TDD-LTE telecommunications use time division multiple access,

which is the same as GSM. But the transmitted power of TD-SCDMA and TDD-LTE is

much less than that of GSM, so their requirements of the power supply are the same

as WCDMA and FDD-LTE.

CDMA telecommunication uses code division multiple access, so its requirement of

the power supply is the same as WCDMA and FDD-LTE.

2.4 Power Consumption

Different Huawei modules have different power consumption, depending on their

platforms. For specific power consumption specifications and test conditions, refer to

the modules' hardware guides.

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

3 Power Supply Design Requirements

3.1 Introduction to Peripheral Power Supplies

Peripheral power supplies provide power for Huawei modules. For Huawei modules

operating in GSM calls and GPRS data transmission on GSM networks, the

transmitted power of Huawei modules can reach 33 dBm (2 W). To prevent

unacceptable voltages drop, power supplies must have good transient response.

These factors must be considered for designing power supplies for Huawei modules.

When designing peripheral power supplies, focus on the following:

- Reducing Internal Resistance

- Adding Energy Storage Capacitors

- Improving Transient Response of the Power Supply IC

3.2 Reducing Internal Resistance

A main method to reduce the internal resistance of peripheral power supplies is to

use power supply integrated circuits (ICs) with the ability to output great currents. The

greater the output current, the smaller the internal resistance. Power supply ICs with

2.5 A outputs at minimum are recommended.

If using low-dropout (LDO) regulators in peripheral power supply ICs, use LDO

regulators with low dropout voltages. Because the input currents of LDO regulators

are equal to the output currents, LDO regulators with low dropout voltages are

equivalent to LDO regulators with small internal resistance.

If using DC-to-DC (DC-DC) converters in peripheral power supply ICs, pay attention

to the following switch parameters in the manuals: Negative Channel Metal-oxide

Semiconductor (NMOS) Switch On Resistance and Positive Channel Metal-oxide

Semiconductor (PMOS) Switch On Resistance. The switch on resistance must be

small. If peripheral diodes are required for the DC-DC power supply ICs, use

Schottky diodes with low voltage drop. The equivalent series resistance (ESR) of

peripheral power inductors for DC-DC power supply ICs must be as small as possible.

Minimize the power loss and internal resistance in the DC-DC power supply ICs.

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

3.3 Adding Energy Storage Capacitors

If a peripheral power supply cannot provide a transient output of 2 A currents, you

must add a capacitor with sufficient capacitance to storage energy for current

compensation. See Figure 3-1 .

Figure 3-1 Add and energy storage capacitor

Power

supply

Vbat

A real capacitor is equivalent to the combination of one ideal capacitor (C), one

equivalent series inductance (ESL) and one ESR that are connected in series. Figure

3-2 illustrates the model of a real capacitor.

Figure 3-2 Model of a real capacitor

t1 :close

ESL

ESR

R lo a d

Ipeak

t2 :open

Model of a real capacitor

Assume that the original voltage on the ideal capacitor is Vo and the peak current is

Ipeak. When the power supply switch is turned off, the capacitor starts to release

electric charge. Before the switch is turned on, the voltage on the load (Vload) can be

calculated using the following formula:

Vload = Vo – (ESR x Ipeak) – (ESL x Ipeak/ΔtL) – (Ipeak x Δt/C)

= Vo – VESR – VESL – VC.

In the previous formula, the voltage drop (VESL) caused by the ESL only occurs and

exists at moments when the switch is turned on or off. Δt is the time for the current

changes from 0 to Ipeak, usually lasting several µs. When the current is stable, VESL is

0. The ESL of ceramic capacitors and tantalum capacitors is very small and can be

ignored. The ESL of aluminum electrolytic capacitors is large because aluminum

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

electrolytic capacitors have long pins. Therefore, aluminum electrolytic capacitors are

not recommended. In addition, note that ESL also exists on the traces connecting the

capacitor pins and the power supply. To reduce the voltage drop caused by ESL, the

traces should be as wide as possible.

Unlike VESL, VESR and VC cause voltage drop throughout the peak current duration.

Figure 3-3 shows a simple analysis of VESR and VC.

Figure 3-3 Simple analysis of VESR and VC

Vdrop = (ESR x Ipeak) + (Ipeak x Δt/C)

From the previous formula, we can infer that the greater the ESR of capacitors, the

greater the voltage drop. Therefore, capacitors with small ESR should be used. We

can also infer that the smaller the capacitance, the greater the voltage drops.

Therefore, capacitors with large capacitance should be used.

Capacitors with ESR smaller than 0.1 Ω should be used (note that aluminum

electrolytic capacitors have large ESR and are not recommended).

The following describes how to calculate the capacitance of the decoupling capacitor

used in the power supply for a Huawei module operating on a GSM network. Assume

that t1 is the time when the voltage starts to drop, which is also the time when the PA

of the Huawei module starts amplifying power. Assume that t2 is the time when the

PA of the Huawei module stops amplifying power. Then the duration between t1 and

t2 is a time slot during which the power is transmitted. For GSM, Δt = t2 – t1 = 577 µs,

which is equal to a transmission time slot. For GPRS class 10, Δt = t2 – t1 = 577 µs x

2 = 1.15 ms, corresponding to two transmission time slots.

Provided that a capacitor with 0.1 Ω ESR is used, then Ipeak = 2.5 A (at maximum

power) and Δt = 1.15 ms.

Then the voltage drop caused by ESR is:

VESR = ESR x Ipeak = 0.1 Ω x 2.5 A = 0.25 V.

The discharge process of capacitors is a differential process, so:

Vc = Ipeak x Δt/C = 2.5 A x 0.00115/C = 0.0029/C.

Vdrop = 0.25 + 0.0029/C.

Provided that the allowed maximum Vdrop is 0.3 V, then C = 58 mF.

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Obviously, 58 mF is too large. This is the result of a model in which the voltage drop

is compensated only by the capacitor and the power supply IC is ignored. The

previous calculation should be revised based on the conditions in real application.

The result also reveals that the ESR must be smaller. Currently, the minimum ESR of

tantalum capacitors is about 0.05 Ω. If smaller ESR is required, use capacitors

connected in parallel. For example, if we use AVX's TCJB157M006R0070 (150 µF,

6.3 V; nominal ESR: 0.07 Ω) and connect ten such capacitors in parallel, then the

capacitance of these ten capacitors is equivalent to 1500 µF and the ESR is

equivalent to 0.007 Ω.

Δt is related to the transient response duration of the power supply IC. Provided that

the transient response duration of the power supply IC is 100 µs (that is, the power

supply IC can output a 2 A current in 100 µs), then the valid period for current

compensation from the capacitors is 100 µs. Figure 3-4 shows the transient response

performance of a power supply IC.

Figure 3-4 Transient response performance of a certain power supply IC

From Figure 3-4 we can discern that when the transient current suddenly reaches 2 A,

the response duration is about 50 µs. Therefore, the capacitors need to compensate

the current only during this 50 µs. Obviously, Δt is approximately equal to the

transient response duration of the power supply IC.

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Figure 3-5 Transient response duration

IpowerIC

Icap

Transient response duration: t

Figure 3-5 illustrates that the peak current is provided by the compensation current

(Icap) from the capacitors when the power supply IC is in the transient response

duration. After the transient response duration, the capacitors can stop the output

current. Note that Figure 3-5 does not consider the case that the power supply IC will

charge the capacitors after the transient response duration.

In conclusion, if ten 150 µF capacitors are connected in parallel and Δt = 100 µs, then:

Vdrop = (ESR x Ipeak) + (Ipeak x Δt/C)

= (0.007 x 2.5 A) + (2.5 A x 0.0001/0.0015)

= 0.184 V

Vdrop is smaller than 0.3 V, meeting the requirement.

The previous calculation does not consider the transient response of the component that

supplies power to the power supply IC. Therefore, Δt should have a greater value in actual

applications.

From the previous description, we can see that the voltage drop is dependent on the

ESR, transient response duration of the power supply (Δt), and capacitance of the

capacitors. Therefore, the capacitance, ESR, ESL and transient response duration

must be taken into account during the power supply design.

For different network modes, it is all recommended to use four (at least two) TDK

ceramic capacitors (C3216X5R0J107MT0A0N with 1206 package). Its capacitance is

100 μF and withstand voltage is 6.3 V.

3.4 Improving Transient Response of the Power Supply IC

In actual application scenarios, the transient response duration of peripheral power

supply ICs must be determined. Designers need to obtain the information about the

HUAWEI Module Power Supply Design Guide

Power Supply Design Requirements

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

transient response duration from the manual of the power supply ICs to be used. The

shorter the transient response duration, the smaller the capacitance of energy

storage capacitors can be.

Connecting a large capacitor to the input to the power supply IC can also improve the

transient response of the IC. If the transient response of the component that supplies

power to the power supply IC is slow, the transient power supply cannot be ensured

even though the power supply IC has fast transient response.

HUAWEI Module Power Supply Design Guide

External Power Supply Circuits

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

4 External Power Supply Circuits

4.1 Choosing the Power Supply IC

Huawei modules can be used in many application scenarios. Different application

scenarios have different requirements. Therefore, the following requirements are

provided for reference only.

- Requirements for DC-DC converters

Currents of modules operating in GSM mode changes a lot in a very short

moment, and the input voltages of modules also fluctuate greatly. Therefore, DC-

DC converters selected must have fast transient response.

- Operating temperature

Pay attention to the ambient temperature in the operating environment of

modules. Make sure that the ambient temperature is appropriate. It is not

recommended that the modules be used under temperature exceeding their

rated operating temperature.

- Derate the power supplies' voltages and currents before using them (85% of

original ratings is recommended).

Either DC-DC converters or LDO regulators can be used for supplying power to

Huawei modules.

4.2 Power Supply Protection

The components of Huawei modules, such as the PA, are designed for using one Li-

ion battery. These components are sensitive to high voltages. To provide stable

voltages, two-stage power supplies are preferred, that is, reduce the voltages output

from DC-DC power supply ICs before they are input to LDO regulators; then LDO

regulators supply power to modules. If two-stage power supplies cannot be used due

to environmental restrictions, protection should be provided for the power supply

systems of modules. Figure 4-1 shows a power supply protection circuit.

HUAWEI Module Power Supply Design Guide

External Power Supply Circuits

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

Figure 4-1 Power supply protection circuit

Power supply protection circuit

Power supply

input

When the input voltages are within the normal range:

Use the 3.8 V input voltage as an example. The voltage on electrodes of Q1 is

obtained from the voltage split by R1 and R2. Make sure that the Q1 electrode

voltage is not high enough to turn on Q1. The voltage on electrodes of Q2 is obtained

from the voltage split by R3 and R4. Make sure that the Q2 electrode voltage is high

enough to turn on Q2. After Q2 is turned on, the PMOS transistor on the main power

supply line is turned on and the power is supplied to the module.

When the input voltages are not within the normal range:

Use the 4.3 V input voltage as an example. The voltage on electrodes of Q1 is

obtained from the voltage split by R1 and R2. Make sure that the Q1 electrode

voltage is high enough to turn on Q1. Make sure that the Q2 electrode voltage is not

high enough to turn on Q2 after Q1 is turned on. After Q2 is turned off, the PMOS

transistor on the main power supply line is turned off. This provides overvoltage

protection for the module.

Figure 4-1 is a schematic. Except the components marked with parameters, all components in

the schematic must be selected based on specific applications. When selecting components,

consider the temperature impact on the turn-on voltages for the base and emitter of a triode.

4.3 Power-on and Power-off Sequences

For Huawei modules, the power-on and power-off sequences are more important.

Before the modules are completely powered on, do not perform controls and

HUAWEI Module Power Supply Design Guide

External Power Supply Circuits

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

communications of modules, and do not apply high voltages to the modules' control

signals; doing so may cause the modules cannot power on or power off.

4.4 Choosing the Filtering Capacitor

The energy storage capacitors with high capacity are recommended to use at least

three TDK ceramic capacitors (C3216X5R0J107MT0A0N with 1206 package). Its

capacitance is 100 μF and withstand voltage is 6.3 V.

And according to the circuit recommended by HUAWEI, capacitors with different

capacity (such as 100 nF, 33 pF and 22 μF) should be added for filtering of different

frequencies.

HUAWEI Module Power Supply Design Guide

Recommendations for the Layout and

Routing of External Power Supply Circuits

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

5 Recommendations for the Layout and

Routing of External Power Supply Circuits

Recommendations for the layout and routing of external power supply circuits include:

- Arrange the input bypass capacitors for the DC-DC converter as close as

possible to the input pin of the power supply IC. Arrange the output capacitors as

close as possible to the inductors. This can suppress ripples effectively. Route

power supply traces as wide as possible, to meet the requirement for providing

great current when the transmitted power is great.

- The filtering capacitor for the VBAT power supply should be as close as to the

power pin of the module.

- Connect diodes that can protect against overvoltage and reverse connection to

the connector through which external power supply is provided. This can protect

power supply circuits in abnormal situations.

- Arrange the inductor as close as possible to the output pins of the power supply

IC. The traces connecting the power IC and the inductor must be as short as

possible, to avoid switch interference.

- Route all signal traces at least 2 mm away from the area under the power supply

IC's power inductors and large-current diodes. Traces of sensitive analog signals

and clock signals must be at least 5 mm away from power inductors, to reduce

interference.

- Use two different traces for the power ground and the signal ground, and use

single-point grounding. Ensure that the current on a ground return does not flow

to the signal ground.

- If modules are used in harsh environment, reverse voltage protection is required

for external power supply circuits.

HUAWEI Module Power Supply Design Guide

Acronyms and Abbreviations

Issue 02 (2014-11-07)

Huawei Proprietary and Confidential

6 Acronyms and Abbreviations

Acronym or abbreviation

Expansion

3GPP

3rd Generation Partnership Project

CDMA

Code Division Multiple Access

DC/DC

Direct Current to Direct Current

ESL

Equivalent Series Inductance

ESR

Equivalent Series Resistance

GPRS

General Packet Radio Service

GSM

Global System of Mobile communication

LDO

Low Dropout Regulator

LGA

Land Grid Array

LTE

Long Term Evolution

NMOS

Negative Channal Metal-oxide semiconductor

Power Amplifier

PCB

Printed Circuit Board

PMOS

Positive Channal Metal-oxide Semiconductor

WCDMA

Wideband Code Division Multi Access

TDMA

Time Division Multiple Access

TD-SCDMA

Time Division-Synchronous Code Division

Multiple Access

Huawei 01 正文 Module Power Supply Design Guide V100R001 02

HUAWEI Module Power Supply Design Guide-V100R001_02

HUAWEI_Module_Power_Supply_Design_Guide-V100R001_02

HUAWEI_Power_Supply_Guide

HUAWEI Module Power Supply Design Guide-(V100R001_02, English)

HUAWEI Module Power Supply Design Guide-(V100R001_02, English)

Navigation menu

Versions of this User Manual:

Views

Navigation