120AC to 5V no transformer
On Thu, 22 Mar 2001 22:44:47 -0500, you wrote:
That would be a rather big resistor - it would dissipate 14 watts, and
the regulator another 2W - that's a LOT of heat.
You could us a capacitive dropper, but you're looking at a few uF,
which is big and expensive (more so than a small transformer)
>>What about isolation issues?
>That's the price you pay! If you don't want a transformer, you don't get
>the isolation. Make sure you have a fuse on the mains side (input to bridge).
>>Lots of issues here I am sure.
>Not really: just the lack of isolation and the maximum power/current
>through the zener.
oh, and heat!
>Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: lcfltd.comral
>Least Cost Formulations, Ltd. URL: http://lcfltd.com/
>824 Timberlake Drive Tel: 757-467-0954
>Virginia Beach, VA 23464-3239 Fax: 757-467-2947
>"Vere scire est per causas scire"
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