NEC MultiSync 2A Service Manual page 38

4-4
Output smoothing circuit
The fly-bac k voltage generated at the secondary winding of switching transformer T601 is
rectified by D651 and D652. Then, it is smoothed by C651, C652 and C 658 so that DC current is
obtained.
This fly-bac k voltage is maintained constant by controlling the ON duty of 0601 in the converter
circuit.
4-5 Detection error amplifier circuit
The output voltage 110V is divided by resistors, and its voltage is compared to the reference
voltage at the error amplifier IC651. An error is transmitted to the control circuit via a
photocoupler PC601.
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T601 0651
Fig. 4 Output Smoothing Circuit
PC601
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Fig. 5 Detection Error Amplifier Circuit
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R656
R657
VR651
R658
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