Service manual

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P-MOSFET Q852 is used for switching of step-down converter. And FD852/FD853 are the
flywheel diodes.
R874/R875 determine the feedback to IC851 to set up the output to +5V or +3.3V.
L853
Z45/100MHZ
R862
2.7K J
R875
1K F
Q855
PMBS3904
B
E C
Q856
2N3906S
C E
B
PANEL_+5V
C869
1200P K
P10
IC851
TL1451ACN
CT
1
RT
2
1IN+
3
1IN-
4
1FBK
5
1DTC
6
1OUT
7
GND
8
VCC
9
2OUT
10
2DTC
11
2FBK
12
2IN-
13
2IN+
14
SCP
15
RFF
16
Q852
2SJ598
D
G
S
R872
22K
R882
22
C868
470P K
L852
47U
R871
3.3K
FD853
ERB83-004
A K
FD852
ERB83-004
A K
R874
3.09K F
+ C867
220U 25V
12
+
C871
220U 25V
12
V-INVERTER
F851
32V 2A
#8 Inverter Circuit Operation Theory
LCDM Inverter Controller --- OZ9933
OZ9933 is a high performance, cost-effective CCFL controller designed for driving large-size
LCD applications requiring 2 to 6 CCFLs.
The controller converts unregulated DC voltages into a nearly sinusoidal lamp voltage and
current waveforms.
The OZ9933 supports full-bridge power conversion topologies while maintaining high-
efficiency operation, current and voltage regulation, over-voltage and over-current protection,
high drive capability.
The control logic provides s regulated ignition voltage and appropriate protection features for
over-voltage or over-current conditions.
Pin Assignment of OZ9933