akira LCT-20CHST, Service Manual

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Model No.: LCT-20CHST
Version: 1.0
4. PCB Module introduction
The Constitute of the PCB is easier than LP03 chassis, all the Signal Processing are in Main board.
a. Main board Module
Main board Module is the main part of Signal Processing in LCD TV. The input signal is
converted into uniform digital signal, which can be identified by LCM by system control
circuit. Main board module contain two parts of signal processing Module: Philips UOC3
process analog audio and video circuit mainly, MST518 process VGA circuit, signal Format
transform system control circuit mainly. The front module can convert the video IF signal and
audio IF signal from tuner into RGB analog signal and audio signal, this part is named analog
audio and video decoding process. The RGB color from UOC is received by MST518 and
accomplishes A/D conversion, output suitable digital color signal to drive circuit of TFT. 8051
Processor inside UOC is responsible for co-operation the each part of works in system, and
Respond to user operation, which is operated on Control panel (key-press panel Module).
b. Key board Module
It is composed of 7 function keys the user can operate the LCD TV conveniently by using this
Module.
c. Remote control receiving board Module
It is composed of a work indicator light and a remote receive head. The user use the remote
control box by this module can operate the LCD TV conveniently and know the LCD TV
work condition.
d. Earphone output board module
It is composed of a earphone outlet, user can Listen to by earphone conveniently.
e. Inverter board module (include inverter circuit)
The function of the inverter is supply power to light tube in TFT and lighten the back lamp
Unit of TFT module, so the user can see the image on TFT.