7810 output voltage spiking?

[jh.]

Some 78xx regulators *do* output a higher voltage
when there is no output current. Maybe your
switched regulator doesn't draw current in the first
milliseconds ? A 1k resistor from 7810 output
to GND should fix that.

JH.



-----Ursprüngliche Nachricht-----
Von: Rob <cyborg_0 at iquest.net>
An: Synth-DIY list <synth-diy at node12b53.a2000.nl>
Gesendet: Samstag, 21. Oktober 2000 20:19
Betreff: 7810 output voltage spiking?


I have a problem.

I have a power supply that has a 15 volt input supplying voltage to a 7810,
then, I take the 10v out from there and put it into an LTC1044A. But, for
some reason, after being on for about 15 minutes, the LTC1044A dies.

BTW, the 1044 is a switching type regulator.

Now, my question is, could the 7810 be allowing a spike on power-on to get
past regulation and damage the LTC1044A? I would think it unlikely, but I am
wondering if anyone has had such experiences with this sort of thing.
Changing the LTC1044a merely smokes another LTC1044a.

I am seriously believing its this 7810, but, the 7810 does not seem to be
out of regulation, on the contrary is is holding a very solid 10 volts
exactly according to my recently cal'd scope.I have not been able to capture
the power on spike either.

What gives?

Rob