Russell McMahon wrote...

>I will happily
>admit that I do not (yet) know the formal transient performance of "my"
>design...

Somehow, after going 'round and 'round in circles with you on this
design for over a week now, this doesn't surprise me a bit.

Since you've decided- now that we've mentioned it in passing- to do a
bit of testing re transient response, here are two other things to
look at while you're at it:

=46irst, I strongly suggest you do something about that Zener diode and
its low operating current.  At the very least, test a large number of
units (with various manufacturer's diodes) at Tmax and verify your
regulation doesn't go all to pot.  Operating Zener diodes at only a
few score microamperes reverse current is asking for BIG trouble if
you're expecting them to maintain their specified breakdown voltage,
even at room temperature.

And second, take a close look (I'd suggest a VERY close look) at the
effects of output capacitor ESR.  Because of the unique manner in
which this circuit operates, I think you're going to have major
problems keeping your operating frequency within tolerable bounds if
output capacitor ESR goes over a few milliohms.

Dave

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