Wall Wart Voltage

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Michael wrote:

It's an unregulated supply. If it is designed to supply up to 2.5A and
you're only drawing a few uAs the voltage is going to be a LOT higher
than rated, though I have to say >12v sounds a little slack. If you're
nervous about the voltage set up a voltage regulator.

- --
Brendan Gillatt
brendan brendangillatt co uk
http://www.brendangillatt.co.uk
PGP Key: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xBACD7433
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Or try loading it slightly - 10Kohm across them and I normally find they
drop to a fairly acceptable level.

I think that is most likely to work with a switching regulator style
wall-wart. If it is big/heavy, it is likely to have just a transformer
and rectifier inside and relies on the rated current to drag the voltage
down to the rated value.

Pete

If there are spikes that might do something.
You need a 3 ohm resistor to get 2.5 amps.
Figure up to a 30% voltage increase on a normally cheapo supply. A good
unregulated supply can get a 10-15% regulation.
Regulated packs are so cheap and reliable, and low RF noise, that
I buy them from Jameco all the time.

greg