Huawei U8860 Maintenance Manual page 36

U8860
Maintenance Manual
Subsystem Module
Oscillator and
frequency
synthesizer
Antenna
Coupler
User UART interface
interface
subsystem
USB interface
USIM card
interface
Keypad and
backlight
Color LCD and
backlight
TEMMC card
Speaker that
plays back MIDI
Receiver
Issue 1.0 (2011-11-14)
Unit
Use crystal
oscillator instead of
temperature
compensated
oscillator
External antenna,
internal interface
component, antenna
protection
Power coupler
Driver, protection
circuit, output
interface
component
Power supply,
protection circuit,
USIM card holder
Keypad driver
circuit, external
keypad, backlight
LED control circuit
LCD driver,
interface mode, and
backlight control
Power supply,
protection circuit,
connector
Driver mode,
connection mode,
speaker component
Driver mode,
connection mode,
receiver component
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd
9 Principles and Troubleshooting
Function
Generates highly accurate TCXVCO of 19.2 MHz
local reference clock. The QTR8615 embeds LO
for WCDMA and GPS.
The phone provides internal antenna for signal
transmission and supports WCDMA high and low
frequency band. U8860-92 phone antennas include
main antenna, diversity antenna, WiFi/BT antenna,
GPS antenna, FM antenna (headphone)
Couples part of the output power of WCDMA
power amplifier to QTR8615 for power monitoring.
The UART1 interface of the MSM8255 subsystem
is used for Bluetooth and the UART3 is used for
testing.
Indicates the peripheral circuits of USB interface in
MSM8255 subsystem, and unit circuits such as
protection circuit and interface connectors. It is the
major data service channel for the engineering
sample, and can be used to debug and test devices
during R&D.
Mainly includes USIM card holder and related
connection circuits.
Supports GPIO for keypad scanning and provides
backlight LED. When a key is pressed, the
backlight is on. By connecting with PM8058, it
provides brightness adjustment function.
The main LCD is of 16 mega colors. The brightness
of the LCD backlight can be controlled by users.
Mainly includes TEMMC card connector and
related interface circuits
The power of the speaker that plays polyphonic
ringtones when there is an incoming call can be 500
mW. It has sound frequency function that can play
back 20 – 20 KHz ringtones. It can also play
mono-audio MP3 files.
Receiver during a call
31