Dell E2009W - Chapter 3- CIRCUIT THEORY

Service Manual
5
Chapter 3- CIRCUIT THEORY
Block Diagram
There are 4pcs PCBA in this monitor, one is power& inverter board which is a single layer board, one is
interface board , one is keypad which is OSD control. The system function block diagram as below
This PWA is included switching power supplier, inverter for CCFL and interface board.(fig.1)
Lamp1
3
To Panel CCFL
To IF Board
AC Line Filter
ON/OFF Control
Power
MOSFET
Power
Transformer
Inverter Transformer
Photocoupler
MOSFET
+5V DC output
MOSFET
Snubber
&Schottky
2
Lamp4
INL833
AC Input
90V~264V
4
Brightness Control
Feedback
and OVP
Lamp2
PWM Control IC
LD7552B
Rectifier&
Filter
Circuit
+24V DC output
Snubber
&Schottky
Lamp3
Feedback
Control
1
Fig.1
INVERTER POWER