LG L3200A Service Manual - Page 10

DESCRIPTION OF BLOCK DIAGRAM 1. Input Selection Circuit 1) PC Input Selection This block is composed of GM1501(U402) and peripheral devices. 2) Video Input Selection This block is composed of video S/W IC (CXA2040Q, U201) and peripheral devices. There are two inputs in CXA2040Q IC(Video input CVBS, S-video signal). One selected video signal is transmitted a video decoder IC (UPD64011, U904) 2. DDC controller This block is composed of GM1501(U402) and peripheral EEPROM IC(U114,U115). GM1501(U402) 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 (U114,U115). 3. Video Decoder This block is composed of UPD64011 (U904) and peripheral devices. GM 1501 controls this IC through IIC Line. This IC analyzes input signal of CVBS, Y/C and output analyzed signal (16bit interlace signal) to De-interlace block. Analyzed signal has video control signals like Contrast, Brightness, Sharpness, Color, tint signals Including Adaptive Comb Filter. 4. Audio Decoder This block is composed of MSP3420G (U501) and peripheral devices. GM 1501 controls this IC through IIC Line. This IC analyzes audio input signal through A/V Jack and PC audio. The analyzed signals transmitted to audio amplifier (TPA3004, U502). 6. De-interlacer This block is composed of MDIN150(U901) and peripheral devices. GM1501 (U402) controls this IC through IIC Line. And this IC converts 16 Bit Interlaced Y/UV signal to De-interlaced signal. It output converted signal to Format Converter IC(GM 1501, U402). 7. Format Converter This block is composed of GM 1501(U402) and peripheral devices. GM 1501(Scaler,U402) contains MICOM. 1) This IC contain A/D converter, Pre-amp and PLL circuit that converting analog video signal(0.7Vp-p) through D-sub(J101) Pin to digital signal. 2) This IC Decode TMDS signals of 8 line from DVI-D Pin (J102) and transmit to LVDS Transmitter. GM 1501 is Format Converter IC that receives Digital signal and outputs proper frame signal to LCD Module Timing(1366x768,WXGA). 8. DC/DC Converter block DC/DC Converter convert the input 12V, 24V to proper 2.5V, 3.3V, 5V, 1.8V for main control system. For shooting heat trouble, we use the DC/DC converting IC. 9. Caption/V-CHIP block -Only U.S.A This block is composed of M37272(U1001) and peripheral devices. M37272 IC is useful for channel selection system for TV with a closed caption decoder. 10. Power Supply Block This Block generates DC Voltages(12V, 24V) to Main Control system from AC Power(100-240 V, 50/60 Hz, 2.8 A). This Circuit contains PFC(Power Factor correction) circuit. The Minimum of Power efficiency is about 75%. 5. Audio Amplifier This block is composed of TPA3004 (U502) and peripheral devices. The function of the audio amplifier is that to amplify audio L/R signal transmitted from audio decoder. The audio signal is amplified according to pre-defined DC volume control curve. - 10 -