Power Supply (Str-F6654) - NEC DTE-25G5THS Service Manual

Service Manual CP-785A

5-8 Power supply (STR-F6654)

5-8 -1 STR-F6654 general description
The STR-F6654 is an hybrid IC with a build-in MOSFET and control IC, designed for flyback converter
type switch mode power supply applications.
5-8 -2 Power supply primary part operations
An oscillator generates pulses signals which turn on and off a MOSFET transistor.
* Start -up circuit: V
IN
The start-up circuit is used to start and stop the operation of the control IC, by detecting a voltage
appearing at V pin (pin 4).
IN
T801 SMPS TRANS
4 6
2 7
D804
D801
C804
R805
D805
C805
R819
D802
C803
D803
L801
R802
C806
3
4
Drain Vin
Main AC voltage
I801 STR-F6653
Ground
5
Power supply start-up circuit
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