On 3/21/07, Vasile Surducan <piclist9@gmail.com> wrote:
> Based on drawing  ES-I is input and E_O is output and here the
> protection could be OK.
> Orin, a stabilizer circuit (even the three terminal one) has a
> negative feedback, so the voltage can't grow to 11.4V even in bad
> dreams. If the supply is based on a three terminal stabilizer the
> reverse diode between Vin and Vout will become on and the spike will
> be absorbed in the filtering cell.

Well, that all depends on Vin to the regulator which is undefined...
as you note, the supply schematics aren't given.

Then the problem being protected against was a short to 12V, not just
a spike.  What if Vin to the regulator is the same 12V?

Orin.
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