Service manual

Service Manual
5
Chapter 3- CIRCUIT THEORY
Block Diagram
There are 2pcs PCBA in this monitor, one is power& inverter board which is a single layer board,
one is interface board .The system function block diagram as below.This PWA is included
switching power supplier, inverter for CCFL and interface board.(fig.1)
Feedback
Control
1
Lamp1
To Panel CCFL
To IF Board
AC Line Filter
ON/OFF Control
Power
Transformer
Power
MOSFET
Photocoupler
Inverter Transformer
MOSFET
+5V DC output
Snubber
&Schottky
2
INL836
AC Input
90V~264V
Brightness Control
Feedback
and OVP
Lamp2
PWM Control IC
LD7552B
Rectifier&
Filter
Circuit
Snubber
&Schottky
+12V DC output
24C02
Mstar TSUM1PEJ-LF-2
I2C
Flash
LVDS for 2 Channels
VGA Connector
5V
14.318MHz
LM1117MPX-1.8
DVI
3.3V
AP1117E33A/
I2C
Brightness Control
DVI Connector
VGA
LM1117MPX-3.3
24C04
Wire Harness for 1 Channel
1.8V
One Connector
AP1117E18A/
XTAL
ON/OFF Control
SPI
Connector
24C02
Connector
5V
Scalar
Keypad
Panel Interface
I2C
DVI For Reserved
Fig.1
INVERTER POWER