I see circuits like these in VCRs a lot... not really anywhere else, for
some reason. Not the greatest efficiency, but the parts are a lot cheaper
than a whole UC3842 or TL494 deal. Maybe not worthwhile against TOPswitches
and such these days.

Efficiency as shown is around 67%. Runs at ~200kHz full power, much slower
at lighter loadings (it fires a full cycle, then stays off for a while)

Tim

--
Deep Friar: a very philosophical monk.
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