Dell E2009W, Руководство по обслуживанию

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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)
Lamp
1
3
T
o
P
a
n
e
l
C
C
F
L
To
I
F
B
o
a
rd
AC Line Filter
ON/OFF Control
Power
MOSFET
Power
Transformer
In
ver
te
r
Tr
a
n
sf
or
m
e
r
Photocoupler
MOSFET
+5V DC output
MOSFET
Snubber
&Schottky
2
La
m
p
4
INL833
AC Input
90V~264V
4
Brightness Control
Feedback
and OVP
Lamp
2
PWM Control IC
LD7552B
Rectifier&
Filter
Circuit
+24V DC output
Snubber
&Schottky
La
m
p
3
Feedback
Control
1
Fig.1
INVERTER POWER