LG Flatron L3020T, Монитор сервиса

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DESCRIPTION OF BLOCK DIAGRAM
1. Input Selection Circuit
1) Analog Input Selection
This block is composed of BA7657F(U103) and
peripheral devices.
There are analog H/V Syncs. BA7657F IC chooses one
input and outputs selected input through sync selection
pin (Pin 1).
2) Video Input Selection
This block is composed of video S/W IC (CXA2040Q,
U3) and peripheral devices. There are three inputs in
CXA2040Q IC(CVBS video signal through RF tuner,
video input CVBS, S-video signal). One selected video
signal is transmitted a video decoder IC (VPC3230, U1)
2. DDC controller
This block is composed of GM1501(U402) and
peripheral EEPROM IC(U107,U108).
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 (U107,U108).
3. Video Decoder
This block is composed of VPC 3230 (U1) and
peripheral devices.
GM 1501 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.
4. Audio Decoder
This block is composed of MSP3420G (U503) 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, U505).
5. Audio Amplifier
This block is composed of TPA3004 (U505) 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. Also, Headphone
amplifier(Tpa6110, U501) is controlled through Line-
out.
6. De-interlacer
This block is composed of FLI 2310(U301) and
peripheral devices.
GM1501 (U402) controls this IC through IIC Line.
And this IC converts 8 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(J103) Pin to digital signal.
2) This IC Decode TMDS signals of 8 line from DVI-D
Pin (J202) and transmit to LVDS Transmitter.
GM 1501 is Format Converter IC that receives Digital
signal and outputs proper frame signal to LCD Module
Timing(1280x768,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 M37136(U202) and
peripheral devices. M37136 IC is useful for channel
selection system for TV with a closed caption decoder.
It receives text information signal and displays text
information through text receiver decoder. It called
multi-text broadcast.
10. Power Supply Block
This Block generates DC Voltages(12V, 24V) to Main
Control system from AC Power(100-240 V, 50/60 Hz,
1.0 A).
This Circuit contains PFC(Power Factor correction)
circuit.
The Minimum of Power efficiency is about 75%.