LG LM805L-WL, Руководство по обслуживанию

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DESCRIPTION OF BLOCK DIAGRAM
1. Input Selection Circuit
This block is composed of 74LVC257(U5) and peripheral devices.
There are two inputs, Analog and Digital H/V Sync. LVC257 IC chooses one input and outputs selected input
through sync selection pin (Pin 1).
2. A/D Converter
This block is composed of AD9883 (U4) and peripheral devices.
AD9883 includes A/D converter, Pre-amp, and PLL.
The basic RGB signal (0.7Vp-p) is input to R,G,B pin of AD9883(U4).
Input video signal is amplified, Phase locked , A/D converted to 8bits digital signal by this IC(U4)
And send the Digital video signal to PW166B-20T.
U4 makes clock for PW166B-20T
3. TMDS Receiver
This Block is composed of SiI161B (U201) and peripheral devices.
This IC decodes Composite Input signal from DVI-D Pin (J18) and make 8bit digital signal to send
Digital EVEN/ODD signal to PW166B-20T.
4. DDC controller
This block is composed of PW166B-20T(U8) and peripheral devices.
PW166B-20T controls peripheral devices through IIC line.
Major functions are (1) to control Flash memory through DDC-SCLA, DDC-SDAA of D-sub
And (2) to store EDID data in the EEPROM (U17, U30)
5. Video Decoder
This block is composed of SAA7114H (U7) and peripheral devices.
PW166B-20T controls this IC through IIC Line.
This IC analyzes input signal of CVBS, Y/C and output analyzed signal (8bit interlace signal) to De-interlace block.
Analyzed signal has video control signals like Contrast, Brightness, Sharpness, Color, tint signals
Including Adaptive Comb Filter.
6. Audio Decoder
This block is composed of MSP3420G (U49) and peripheral devices.
PW166B-20T controls this IC through IIC Line.
This IC analyzes Audio input signal through A/V Jack and PC audio.
And output the analyzed signals to Audio Amplifier (TDA7268).
7. Audio Amplifier
This block is composed of TDA7268 (U39) and peripheral devices.
It amplifies audio signal input from Audio Decoder and output amplified audio signal to Speaker,
Audio Output Jack.
The output signal form is BTL.
8. De-interlacer
This block is composed of SDA9400 (U16) and peripheral devices.
PW166B-20T (U7) controls this IC through IIC Line.
And this IC convert 8 Bit Interlace Y/UV signal to De-interlace signal.
It output converted signal to Format Converter (PW166B-20T).
9. Format Converter
This block is composed of PW166B-20T (U8), M29W800DT (U19) and peripheral devices.
MICOM in PW166B-20T (U7) processes outputs of A/D Converter and TMDS Receiver,
De-interlace output and output processed 48 Bit Digital signal to TMDS Transmitter.
PW166B-20T is Format Converter IC that receive Digital signal and output proper frame signal to
LCD Module(1280x1024).