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8-5. Error Detection Amplifier Circuit
The output v80.2V is compared with the reference voltage at the error amplifier IC671.
An error signal is applied to the control circuit via the photocupler PC621.
(Fig.8-5) Error Detection Amplifier Circuit
8-6. Over Voltage Protection
If some failure occurs and the output voltage of the secondary windings of T601 increase, the voltage of the
auxiliary winding of T601 also increase proportionally. When the voltage of C623 and IC621 pin 9 increase.
This action will stop the oscillator with in IC.
(Fig.8-6) Over Voltage Protection
CONTROL
CIRCUIT
+80.2V
GND
PC621
R674
IC671
R675
C673
2
1
3
IC621
D623
D625
T601
9
VIN
+
GND
-
2
C623