John La Rooy wrote:
> Could you not just add a zener in the feedback leg of the SMPS so it
> always
> tries to output Vzener volts above the voltage you have dialed?

I usually use a PNP transistor so that it turns on when the switcher output
is the E-B drop above the linear output.  The collector signal is then the
output high/low feedback into the switcher controller.


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