Description Of Block Diagram - LG FLATRON L1800PM Service Manual

1. Input signal switching part(BA7657).
There are two anolog inputs which are D-Sub analog and DVI-anolog input.
They come from each 15 pin D-Sub and 29 pin DVI-I connector.
2. Video Controller Part(GM5020).
This part amplifies the level of video signal for the anolog to digital conversion and converts from the analog video
signal to the digital video signal using a pixelclock.
The pixel clock for each mode is generated by the PLL.
The range of the pixel clock is from 25MHz to 135MHz.
This part consists of the Scaler and frame buffers which converts frame rate of input signal to 60Hz frame rate.
The Scaler gets the video signal converted analog to digital, interpolates input to1280 X 1024 resolution signal and
outputs 8-bit R, G, B signal to transmitter.
Especially pre-amp / ADC / Video controller are merged to one chip 'Gm5020' by Genesis.
Also FRC is separate.
3. Display Data Transmitter Part(LVDS).
This part transmit digital signal from the Scaler to the receiver of module.
4. Power Part.
This part consists of the one 5V, two 3.3V and one 2.5 regulators to convert power which is provided 12V, 5V in
Power Board.
12V is provided for inverter, 5V is provided for Micom and LCD Panel.
Also, 5V is converted 3.3V and 2.5V by regulator. Converted power is provided for IC in the main board.
5. MICOM Part.
This part consists of EEPROM IC which stores control data, Reset IC and the Micom.
The Micom distinguishes polarity and frequency of the H/V sync are supplied from signal cable.
The controlled data of each modes is stored in EEPROM.
6. Inverter
The inverter converts from DC12V to AC 700Vrms and operate back-light lamp of module.
7. Audio Part
Input voltage is DC12V from Main board Audio Signal AC 700Vrms is amplified.

DESCRIPTION OF BLOCK DIAGRAM

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