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133
DP23/23G/24
PROTECT
_DEF
Side Pin Failure
High Det.
Flyback
5OP
29.01V
OVP
TH01
ABL Voltage
Too High Det.
RH32
Hi Volt
Drive
7
5
LH06
Excessive Hi
Voltage Det.
RH23
CH17
RK97
DK90
D703
D702
HZS7C3
RK98
-5V
+5V
Convergence Out Circuit
-5V Loss
Detection
3
ABL
Stops H. Drive
Side Pincushion Circuit
10
Vertical Output Circuit
R630
R631
C610
6
DH15
R629 0.68 Ohm
Q604
28V
D608
Excessive Vertical
Current Det.
R632
7
See Low Voltage Shut Down
Circuit Diagram for continuation.
RH32 allows ABL fluctuations to
manipulate the Trigger Point of Shut
Down as screen brightness varies. ABL
is inverse proportionate to brightness.
This prevents false triggering.
Any fluctuations in High Voltage will
also be reflected by the 50P output P/P.
By monitoring the 50P (50 Pulse) rises
in High Voltage will be sensed. If High
Voltage climbs too high, DH15 will fire
and trigger a shut down event.
A loss of the Negative 5V will cause the
positive 5V to be felt on the anode of
DK90 which forward biases the diode
and delivers a Shut Down high.
If the Vertical Output IC has a problem,
R629 will sense the current rise. The
voltage drop will be reflected at the base
of Q604 turning it on and producing a
Shut Down high.
D702 monitors the Side Pin
Drive IC. If the voltage at
pin 7 rises too high, D702
will fire generating a Shut
Down high.
High Voltage
Sensing Circuit
PPD3
DH13
DH14
1
RH26
R717
RH24
RH25
Summary of Contents for 43FWX20B
Page 34: ...34 DP23 23G 24 CONTROL P W B DP23 DP23G BACK TO ADJUSTMENTS ...
Page 72: ...PRINTED CIRCUIT BOARD Control P W B Pattern Side 72 DP23 23G 24 ...
Page 73: ...DP23 23G 24 PRINTED CIRCUIT BOARD Control P W B Part Side 73 ...
Page 74: ...DP23 23G 24 BLOCK DIAGRAM DP23 DP23G 74 ...
Page 75: ...DP23 23G 24 BLOCK DIAGRAM DP24 75 ...
Page 76: ...DP23 23G 24 WIRING DIAGRAM DP23 DP23G 76 ...
Page 77: ...DP23 23G 24 WIRING DIAGRAM DP24 77 ...
Page 83: ...DP23 23G 24 83 DP24 FINAL WIRING DRAWING ...
Page 125: ...125 DP23 23G 24 ...
Page 129: ...129 DP23 23G 24 ...
Page 130: ...130 DP23 23G 24 ...
Page 131: ...131 DP23 23G 24 ...
Page 134: ...134 DP23 23G 24 ...
Page 135: ...135 DP23 23G 24 ...
Page 136: ...136 DP23 23G 24 ...
Page 137: ...137 DP23 23G 24 ...
Page 140: ...140 DP23 23G 24 ...
Page 143: ...143 DP23 23G 24 ...
Page 144: ...144 DP23 23G 24 ...
Page 145: ...145 DP23 23G 24 ...
Page 147: ...147 DP23 23G 24 ...
Page 150: ...150 DP23 23G 24 ...
Page 151: ...151 DP23 23G 24 ...
Page 152: ...152 DP23 23G 24 ...
Page 153: ...153 DP23 23G 24 ...
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