電源技術-電源IC資料(pdf 16)

The NCP1215 is a controller for low power off-line flyback
Switched Mode Power Supplies (SMPS) featuring low size, weight
and cost constraints together with a good low standby power
performance. The operating principle uses switching frequency
reduction at light load by increasing the OFF Time. Also, when OFF
Time expands, the peak current is gradually reduced down to
approximately 1/4 of the maximum peak current to prevent from
exciting the transformer mechanical resonances. The risk of acoustic
noise is thus greatly diminished while keeping good standby power
performance.
A low power internal supply block also ensures very low current
consumption at start-up without hampering the standby power
performance.
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