Circuit Descriptions - LG 42PG20 Training Manual

MAIN bOARD bOTTOM
Be sure to prevent the board from touching the frame while the board is turned over. Use
a piece of cardboard or towel to insulate.
Main ICs
Chip Pin Voltage
1 5V
IC705 2 3.29V
3 0V
1 5V
IC706 2 2.6V
3 1.37V
1 5V
IC708 2 3.31V
3 0V
1 3.29V
IC709 2 1.26V
3 0V
To keys and IR
1 3.3V
To Speakers
IC501 2 1.8V
3 0V
1 5V
IC805 2 3.3V
3 0V
1 5V
IC101 2 0V
3 5V
LVDS
P701
IC705
*
IC709
P302
MAIN
*
PCB
Q706
LD703
*
IC708
P303
*
IC501
JK501
IC805
*
LD400
X400
TUNER
25 Meg
Run Only
TUNER
*

CIRCUIT DeSCRIPTIONS

IC709
IC101
Reset
*
*
IC101
**LD400
IC100
Micro
25 Meg
Run Only
X100
12 Meg
1.5V SBY
Grayed Out ICs are
located on Back
*
*
Reset
MAIN PCB
"Back View"
IC1001
X100
12 Meg
1.5V SBY
*
Grayed Out ICs are
located on Front
IC705
IC702
IC706
Pin 16
X400
Pin 1
IC708
TUNER
IC501
TUNER
Pin 16 Video
Pin 14 SIF
Pin 1
*
IC805
P701
LVDS
*
*
P302
LD703
P303
*
To keys and IR
JK501
To Speakers
PDP Training - Fall 2008
4
2
P
IC702
IC
5) .29V
1)
G
4) 5V
2)
3) 0V
3)
2) 0V
IC5
1) 0V
1)
2
IC705
2)
1) 5V
3)
2) 3.29V
3) 0V
0
IC8
IC706
1)
1) 5V
2)
2) 2.6V
3)
3) 1.37V
IC1
IC708
1)
1) 5V
2) 3.31V 2)
3)
3) 0V
57