Pipu Board Hardware Structure - Huawei ETS2000 Series Maintenance Manual

the voice coding/decoding unit is to conduct compressing and coding operations
over 64K voice and digital code traffics like EVRC codes, to let them be suitable
for being transmitted in wireless environment. The baseband signal processing unit
mainly includes functions like baseband modulation/demodulation and channel
coding/decoding. It also includes the CPU system through which protocol software
runs, as well as FLASH for storing software and SRAM for running software.
The power and power-management modules fulfils functions like system power
supply and power management.
The radio frequency sub-system includes radio frequency processing unit and
antenna feeder system. Radio frequency signal processing functions cover
functions of modulating and demodulating baseband signals, power amplifying,
and frequency modifying. The primary function is to convert baseband signals into
radio frequency signals proper for wireless transmission and the reverse function.
The corresponding proper interface is the Um interface of CDMA2000 1x.
PIPU board interface module mainly provides power, PCM interface, UART
interface, USB interface and R-UIM interface. It is a 72PIN pad

1.2.2 PIPU Board Hardware Structure

primary power
LCD module
Keypad
handle
speaker
microphone
A shown in Figure 1-3, the PIPU board mainly includes the following circuit
modules, user sub-system, power supply and power management module.
The user sub-system includes serial port protection module, R_UIM card interface,
audio channels 1 and 2, environmental variable monitoring module, etc.
power switch
protection module
startup/
shutdown
second-time
control
power switchover
second-time power
Hook
LCD BUS
LCD interface
KPAD interface
audio
4-wire interface channel 1
audio
channel 2
R-UIM interface
Figure1-3 PIPU board hardware structure
5
DB9
serial port
protection
72Pin TCPU module pad
second-time power
charging control
charging circuit
battery
antenna
antenna
interface