Hi Joop,

Interesting circuit.

Where does the R1/D1/Q/.Q2 reference point connect to ?

I assume the parasitic diodes in Q1/Q2 form a current path ?

-Mark


On Nov 30, 2:54*am, Joop wrote:
On Sun, 29 Nov 2009 00:33:13 -0800 (PST), MarkAren

wrote:
Bingo !

http://www.idesignz.org/misc/Simple%...tage%20PSU.pdf

Thanks,

Mark

This is a circuit that does not suffer from temporary abcense of power
during switching. And it is using a transformer with a single
secundary winding.http://www.gigawatts.nl/co/projects/...bel/switch.jpg

Joop