LG 20LC1R-ZG, Service Manual

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BLOCK DIAGRAM DESCRIPTION
Power Supply Block (LIPS)
This Block Generates DC Voltage (5V,15V) to Main
Control system from AC Power (100-240 V, 50/60 Hz,
1.0A)
Also it has the inverter function that converts input
voltage to AC Rms value for the LCD lamp.
DC/DC Converter block
DC/DC Converter convert the input 5V,15V to proper
3.3V, 5V, 8V, 12V for Main control system.
For shooting heat trouble, we use the DC/DC
converting IC
Audio Amplifier
This block is composed of TPA3005D2 and peripheral
device.
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.
Audio / Video / IF Decoder / Scaler
This block is composed of LOC1 and peripheral
devices.
1) Video Decoder
This Block Selects input Video signals (like CVBS, Y/C,
SCART RGB) and output RGB signal.
On decoding, We can control signal like Contrast,
Brightness, Sharpness, Color, tint signals including
Adaptive Comb Filter
2) Audio Decoder
This block analyzes audio input signal through A/V Jack
and PC audio and Tuner IF.
The analyzed signals transmitted to audio amplifier
On decoding, We can control signal like Bass, treble.
3) IF Decoder
This block can change IF signal to audio and video
signal that transmitted to Video/audio decoder.
4) Scaler
This IC includes A/D Converter and LVDS Transmitter
This IC is directly Inputted Analog Signal and transmits
it to LCD Module
5) Micom
This block controls each IC through IIC communication
line.
LVDS Rx (DTC34LF86L)
It is composed of DTC34LF86L/THC63LVDF84B.
The LVDS Rx converts the LVDS data streams back
into 24bits of CMOS/TTL data with
Falling edge or rising edge clock for convenient with
variety of LCD panel controllers.
Switch IC (PI3V512QE)
It is composed of PI3V512QE.
This IC selects between D-sub RGB signal and LOC1
RGB signal, and it transmits the selected signal to
video signal processor.
TUNER
Micom controls this through IIC Line.
TUNER makes IF and transmits IF signal to LOC1.