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Huawei U8185 Maintenance Manual

Huawei U8185 Maintenance Manual

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U8185
Maintenance Manual
Issue
1.0
Date
2012-03-23
HUAWEI TECHNOLOGIES CO., LTD.

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Summary of Contents for Huawei U8185

  • Page 1 U8185 Maintenance Manual Issue Date 2012-03-23 HUAWEI TECHNOLOGIES CO., LTD.
  • Page 2 Notice The purchased products, services and feat ures are stipulated by the contract made bet ween Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchas e scope or the usage scope. Unless otherwis e specified in the contrac t, all statements, information, and recommendations in this document are provided "AS IS"...

  • Page 3: About This Document

    Reviewed by Maintenance support team Date 2012-03-23 Approved by Service representative Date 2012-03-23 Change History Date Version Change Reason Section Description Author 2012-03-20 V1.0 Released R&D first issue. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 4: Table Of Contents

    9.3 RF Un it ....................................34 9.3.1 GSM Quad Band Transception Circu it ......................36 9.3.2 WCDMA2100/1900 Transception Circuit ......................39 9.3.3 W900/ 850 Transception Circuit ..........................43 9.4 Peripheral Circu its ................................48 Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 5 9.4.12 Wi-Fi..................................73 10 Solder Points on the PCB and BGA Chip ................. 75 11 Functional Tests........................... 81 11.1 Keys ....................................81 11.2 MMI Test ..................................82 11.3 Voice Call Test................................83 Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 6: Product Introduction

    Product Introduction 1.1 Appearance Figure 1-1 U8185 1.2 Specifications Category Description Dimensions (H x W x D) 106.5 mm x 56 mm x 10.9 mm Technical standard WCDMA/GSM Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 7 Standby time: up to 280 hours Display Resolution 240 RGB x 320 pixel Type TFT-LCD Color 262 k Size 2.83 inches Connectors Charging port Micro USB connector USB port Micro USB connector Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 8 GSM 850/900/1800/1900 MHz: better than –102 dBm/200 kHz  Operating temperature: –10° C to +55° C Temperature  Storage temperature: –40° C to +70° C  Humidity Operating humidity: 5% to 95% RH Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 9: Applicable Scope And Precautions

    2.1 Applicable Scope This document provides repair instructions for technicians at service centers authorized by Huawei. This maintenance manual is confidential and accessible to authorized service centers (ASCs) and authorized service providers (ASPs) only. While every effort has been made to ensure the accuracy of this document, errors may still exist.

  • Page 10: Exploded View

    Table 3-1 List of components in the exploded view drawing Description Quantity Touch panel (TP) Front cover assembly Printed circuit board assembly (PCBA) Rear cover assembly Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 11 U8185 Maintenance Manual 3 Exp loded View Description Quantity Battery Battery cover Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 12: Components On The Pcba

    U3202 RF switch MIC1501 MIC Failure of this Failure of this component can cause: component can cause: Signal receive or transmit No sound is picked or failure transmitted Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 13 The following list of components is provided for reference only. This list is subject to change without notice. The latest component list is available on Huawei's ITEM information system. If you have any questions, please contact your local technical support.
  • Page 14 SAW filter U4102, U4103 47090042 RF low-noise amplifier U5002 39210040 Bluetooth & FM chip U6000 39210039 WLAN chip U6100 47140101 RF switch U6202 12020125 Crystal resonator X301 Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 15: Software Upgrade

    Before the upgrade, NV items backup is performed (if the phone's NV items has not been backed up before). Then the phone restarts and the upgrade starts. The upgrade progress is displayed on the LCD. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 16: Troubleshooting

    Check that the upgrade file is correct. in microSD card upgrade mode.  Check that the upgrade method is correct.  Check that the microSD card functions properly.  Perform the upgrade again. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 17: Maintenance Tools

    Usage: to heat components Name: soldering iron Usage: to maintain and solder components Name: DC power supply Usage: to supply DC current Name: soldering table Usage: to secure the PCBA Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 18 Usage: to solder components Name: digital multimeter Usage: to measure during repair Name: toolkit Usage: to assemble and disassemble components Name: electric screwdriver Usage: to fasten and remove screws Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 19: Disassembly Procedure

    1. Wear an ESD wrist strap, and ensure that the strap is 2. U8185 before disassembly grounded properly. 3. Remove the battery cover. 4. Remove the four screws from rear cover. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 20 8. Remove the PCBA from the front cover. key dome, and Power key dome. 10. Remove the LCD. The phone is then disassembled. 9. Open the LCD connector. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 21: Assembly Procedure

    4. Install the TP connector, Volume key dome, and the TP connector FPC under the PCBA. Power key dome, and then snap latch between the PCBA and front cover in place. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 22 5. Install the Power key and Volume key, and snap the 6. Install the four screws into the rear cover. front and rear covers. 7. Install the battery cover. 8. The phone is now assembled. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 23: Principles And Failure Analysis

    Before repairing a phone, ensure that the failure of the phone is not caused by environmental factors or incorrect functional settings. It is recommended that you restore the phone to its factory settings. 9.1 Block Diagram Figure 9-1 U8185 block diagram HD1U8185M.pdf Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential...

  • Page 24: Baseband Unit

    Maintenance Manual 9 Principles and Failure Analysis The MSM7X2XA (the U8185 uses the MSM7225A) is the baseband signal processing chip, mainly responsible for processing the input and output of IMAGE, VIDEO, AUDIO, RF INTERFACES, and CONECTIVIT Y signals. The baseband chip provides keypad, LCD, microSD card, Wi-Fi, camera, and microphone interfaces.
  • Page 25 After the Power key is pressed, the phone powers on. VHP_PWR (main power voltage) powers the PM8029. The power management chip then provides the voltages listed in the following table. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 26 The power-on failure may be caused by any of the following conditions:  No current Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 27 Is U201's output Replace U201 voltage normal? Does X301 have Replace X301 32.768 kHz output? Replace U601 and re-install the phone's software. Is the problem solved? Replace U401 Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 28 Is Q202 normal? Remove U201. Do short Replace U201. circuits still exist? Replace U401. Circuit Diagram Signal Summary See Table 9-1 in section 9.2.2 "Charging Management Circuits." Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 29: Charging Management Circuits

    U8185 Maintenance Manual 9 Principles and Failure Analysis 9.2.2 Charging Management Circuits Figure 9-3 Circuit schematic diagram Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 30 9 Principles and Failure Analysis Analysis The U8185 uses the PM8029 solution for its charging management. The following figure shows the internal structure of the PM8029. The PM8029 has three charging states: trickle charging, constant current charging, and constant voltage charging. A universal charging channel is used: VEXT_DC→VCHG→Q201, pin3→VBAT...
  • Page 31 VCHG to 0 V to make sure that the charger is detected as not connected. The parallel connected capacitor protects the EMC, provides linear filter, and ensures circuit stability.  Trickle charging Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 32 If the battery is fully discharged, Vbat < Vweak and the typical voltage is 3.2 V . To protect the VDD from being pulled down, trickle charging is performed.  Constant current charging Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 33 During constant voltage charging, the VDD voltage remains unchanged. When Vbat is equal to Vmaxsel and the charging current is lower than the threshold, the charging is complete.  Pulsed charging Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 34 Replace Q201 available on C237? Is the battery in good contact with Repair or replace J902 the battery connector J902? Is the battery damaged? Replace the battery Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 35 Supplies power to the eMMC module on the MSM. VREG_L12 Supplies power to the TCXO_OUT_D1 buffer, AMUX, and XO ADC circuits. VREG_L13 Supplies power to the SD circuit. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 36: Clock Circuit

    VREG_L19 Supplies power to the AR6005 Wi-Fi module. 1.8 V 9.2.3 Clock Circuit Circuit Schematic Diagram Figure 9-4 32.768 kHz clock Figure 9-5 19.2 MHz system clock Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 37: Memory Circuit

    The crystal oscillator generates the 19.2 MHz clock as the system clock, and the crystal X301 generates the 32.768 kHz clock, as shown in the preceding figure. 9.2.4 Memory Circuit Figure 9-6 Circuit schematic diagram Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 38 NAND_RE_N Flash read enable; valid when at low level None. NAND_WE_N Flash write enable; valid when at low level None. NAND_CLE Flash command latch enable None. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 39: Rf Unit

    9.3 RF Unit The RF unit transmits signals between the baseband and the antenna. If any problem occurs during transmission and reception, troubleshoot according to the following flowchart. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 40 R3201 on the power voltage normal? supply network, or replace R3210, R3211, or R3212 on the control Troubleshoot as circuit described in the following sections Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 41: Gsm Quad Band Transception Circuit

    RF transmitter > Signals are amplified by the power amplifier > Signals are transmitted out from the antenna switch after frequency switchover. Figure 9-8 Receiving circuit Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 42 9 Principles and Failure Analysis GSM quad band adopts differentiated reception to match the network. Troubleshooting Process Failure: No transmission; the phone cannot initiate or receive a call. Solution: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 43 C3501, or C3502 on the voltage normal? power supply network, or replace C3518 or C3519 on the control Send the phone to an circuit advanced service site for repair Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 44: Wcdma2100/1900 Transception Circuit

    L3603 soldered them properly? Send the phone to an advanced service site for repair 9.3.2 WCDMA2100/1900 Transception Circuit W2100/1900 RF transception circuit filter, PA, duplexer, and antenna switch Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 45 ANT end to the duplexer and then sent out through the antenna. The duplexer's Rx and Tx ends are isolated, preventing transmission signals from interfering to receiving signals and thereby affecting antenna sensitivity.  Receiving circuit Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 46 Quadrature Downconverter and become I/Q signals > After analog-to-digital conversion (ADC), signals are transmitted to CPU for processing. Troubleshooting Process Failure: No transmission; the phone cannot initiate or receive a call, or access the network. Solution: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 47 Send the phone to an advanced service site for repair Failure: No reception; the phone cannot initiate or receive a call, or access the network. Solution: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 48: W900/850 Transception Circuit

    C3702 soldered them properly? Send the phone to an advanced service site for repair 9.3.3 W900/850 Transception Circuit W900/850 RF transception circuit filter, PA, duplexer, and antenna switch Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 49 The receiving signals are received from the ANT end of the duplexer and transmitted out from the Rx end; the transmitting signals are received from the Tx end and Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 50 Quadrature Downconverter and become I/Q signals > After analog-to-digital conversion (ADC), signals are transmitted to CPU for processing. Troubleshooting Process Failure: No transmission; the phone cannot initiate or receive a call, or access the network. Solution: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 51 Send the phone to an advanced service site for repair Failure: No reception; the phone cannot initiate or receive a call, or access the network. Solution: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 52 Is U3404 soldered Re-solder or replace it properly? Are C3611, C3612, Re-solder or replace and L3612 soldered them properly? Send the phone to an advanced service site for repair Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 53: Peripheral Circuits

    9.4.1 Display Figure 9-12 Circuit schematic diagram Analysis The U8185's LCM uses a 262k TFT-LCD (240 x 320 pixels) and a serial interface with synchronous clock. The MSM7225A provides the drive current. The LCM is provided by the supplier directly.
  • Page 54 LCDC_SPI_CS Chip select signal; valid when at low level None. LCDC_SPI_SCLK Serial clock signal None. LCDC_SPI_SDO Serial data output signal None. LCDC_SPI_SDI Serial data input signal None. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 55: Keypad

    LED_K4/ VREG_L12_2P85 Supplies power to the analog section. None. VREG_S3 Supplies power to the I/O port circuit. None. 9.4.2 Keypad Circuit Schematic Diagram Figure 9-14 Power key Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 56 Figure 9-16 V olume key Analysis The U8185 has a Power key, V olume key, and Home key. When the phone is powered off, press the Power key (PWR_ON). The KPD_PWR_ON signal is then pulled down. This signal is connected to the control switch of the power management module and triggers the power management module to power on.
  • Page 57 Replace the spring phone . Is the spring damaged? Replace the home Is the FPC lack of key FPC pad? Re-install the software or replace the CPU Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 58: Vibration

    BTB socket. When the motor is not vibrating, VPH_PWR and VIB_DRV_N are both at high level. Troubleshooting Process Failure: The motor fails to vibrate. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 59: O Ice Reception

    Main power supply, supplying power None. to the motor VIB_DRV_N Motor drive signal pin, connected to None. the motor's negative electrode 9.4.4 Voice Reception Figure 9-22 Circuit schematic diagram Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 60 U8185 Maintenance Manual 9 Principles and Failure Analysis Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 61 Maintenance Manual 9 Principles and Failure Analysis Analysis Figure 9-23 MSM7225A's internal audio structure Figure 9-24 PM8029's internal audio structure The U8185 provides three types of audio output: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 62 500 mW power. The speaker is on the rear cover and is in contact with the PCBA through a spring. Headset output: The U8185 is designed with a stereo headset. Troubleshooting Process Failure: After a call is established, no sound can be heard.

  • Page 63: O Ice Transmission

    Figure 9-26 Circuit schematic diagram Analysis The U8185 has two microphone circuits: the main microphone and headset microphone circuits. The main microphone circuit uses a –44 dB omnidirectional electret condenser microphone with differential outputs to the MSM7225A's MIC1_P and MIC1_N. The name of electret condenser microphone comes from its sound sensing structure similar to a condenser (capacitor).
  • Page 64 1.8 V? Replace the microphone. Problem solved? Send the phone to an advanced service site for repair Circuit Diagram Signal Summary See section 9.4.6 "Headset." Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 65: Headset

    9.4.6 Headset Figure 9-29 Circuit schematic diagram Analysis The U8185 adopts a stereo headset design. The headset port is in the IO. The headset output uses the amplifier of the PM8029. Troubleshooting Process Failure: No sound can be heard from the headset.
  • Page 66 Speaker's positive electrode Speaker wave forms measured over its two electrodes EAR1_M Receiver's negative electrode EAR1_P Receiver's positive electrode Receiver wave forms measured over electrodes, receiving mono sound Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 67  HS_DETECT_N Headset presence detection pin  When no headset is inserted, EAR_DETECT is at high level. When a headset is inserted, EAR_DETECT is at low level. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 68: Sim Card

    Figure 9-30 Circuit schematic diagram Analysis The U8185 supports the R_UIM card and connects the R_UIM card through the UIM card slot. The PM8029 provides the card slot with VREG_L16_RUIM power of 2.85 V . The R_UIM card's reset, clock, and data signals can be sent to and received from the PM8029 directly.
  • Page 69 Kept at low level after the phone is powered on.  UIM1_RESET_ESD ESD protection for the UIM None. card reset signal  Connected to the ESD protection component D606 Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 70: I/O Connector

    Solution: Clean, re-solder or replace the USB connector. Table 9-7 Circuit diagram signal summary Signal Description Reference Measurement or Wave Form VCHG Charging current High level, 5 V input Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 71: Microsd Card Connector

    Figure 9-32 Circuit schematic diagram Analysis The U8185 supports 8 GB microSD cards. The power consumption of 512 MB and 256 MB microSD cards is low, while the power consumption for microSD cards of 1 GB or higher is comparatively high, which is normal. To increase RF capability, 33 pF capacitors are added to all data lines.
  • Page 72 Is the microSD card slot soldered Re-solder or replace it properly? Send the phone to an advanced service site for repair 9.4.10 FM Figure 9-34 Circuit schematic diagram Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 73 9 Principles and Failure Analysis Analysis The U8185 uses Qualcomm's WCN2243 FM/Bluetooth chip to receive and process FM signals and realize the FM function. The stereo signals from the FM module are amplified by the MSM7225A and then sent to the headset or speaker.
  • Page 74 Problem solved? Does signal exist on I2C? Is U6000 soldered Re-solder or replace it properly? Send the phone to an advanced service site for repair Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 75: Bluetooth

    See section 9.4.11 "Bluetooth." 9.4.11 Bluetooth Figure 9-35 Circuit schematic diagram Analysis The U8185 uses Qualcomm's WCN2243 FM/Bluetooth chip to receive and process Bluetooth signals and realize the Bluetooth function. WCN2243 Bluetooth section's major features:  Bluetooth baseband processor integrated with 2.4 GHz transceiver ...
  • Page 76 Sleep control and coexisting  I2S interface  PCM interface Table 9-8 Circuit diagram signal summary Signal Description Reference Measurement or Wave Form BT_RFIO RF transmission and reception Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 77 Right audio channel output of the FM radio I2C_SCL I2C bus clock I2C_SDA I2C bus data FM_I2S_SD I2S bus data FM_I2S_WS I2S bus byte-select line FM_I2S_SCK I2S bus clock FM_RDS_INT FM RDS interrupt Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 78: Wi-Fi

    U8185 Maintenance Manual 9 Principles and Failure Analysis 9.4.12 Wi-Fi Figure 9-36 Circuit schematic diagram Analysis The U8185 uses QUALCOMM's AR6005 chip to realize the Wi-Fi function and support 802.11n. AR6005 chip's major features:  Support for IEEE 802.11b/g/n ...
  • Page 79 ANTE Shared antenna switch control signal BIAS_REF Internal analog bias reference RF2INN/RF2INP 2.4 GHz input RF2OUTN/RF2OUTP 2.4 GHz output XPABIAS5 External PA bias voltage GPIO GPIO interface Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 80: Solder Points On The Pcb And Bga Chip

    : V acant point  Green (R: 0, G: 255, B: 0) : Ground point  Blue (R: 0, G: 0, B: 255) : Solder point Magnified views of sections: Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 81 U8185 Maintenance Manual 10 Solder Po ints on the PCB and BGA Chip Figure 10-1 PM section Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 82 U8185 Maintenance Manual 10 Solder Po ints on the PCB and BGA Chip Figure 10-2 MSM7225A+NAND MCP section Figure 10-3 Bluetooth/FM section Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 83 U8185 Maintenance Manual 10 Solder Po ints on the PCB and BGA Chip Figure 10-4 Wi-Fi section Figure 10-5 RTR8285A section Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 84 U8185 Maintenance Manual 10 Solder Po ints on the PCB and BGA Chip Figure 10-6 Top surface Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
  • Page 85 U8185 Maintenance Manual 10 Solder Po ints on the PCB and BGA Chip Figure 10-7 Bottom surface Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 86: Functional Tests

    U8185 Maintenance Manual 11 Functional Tests Functional Tests 11.1 Keys Menu Back Search Home key Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 87: Mmi Test

    Test the main microphone, secondary microphone, and dual microphone (main and secondary) in the same way. Press the Volume– key to start the next test. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

  • Page 88: Voice Call Test

    If no problems are found during the test, finish the voice call test. If any problems are found, troubleshoot the phone or send it to an advanced service site for repair. Issue 1.0 (2012-03-23) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

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