# Low Power Embedded DC supply from 120Vac Mains

#### Fish4Fun

##### So long, and Thanks for all the Fish!
Aug 27, 2013
472
For years, a recurring theme in my DIY projects has been a "cheap" DC supply from AC Mains .... and to that end Wall-Warts have generally been the answer ... But sometimes a Wall-Wart simply isn't a good answer ....

Over the years I have spent many, MANY hours conjuring up cost effective DIY solutions ... and like most DIY solutions they all fundamentally failed in at least one (and generally more) of the important four categories:

1) Safety
2) Cost
3) Reliability
4) Efficiency

Recently I have been working on a project that really isn't suited for a Wall-Wart and needs less than 75mA @ 5V .... the temptation to use a voltage divider + capacitor arrangement was strong! But before I wandered too far down the path of dangerous, unreliable and inefficient heaters, I checked ebay ... and guess what?

https://www.ebay.com/itm/10pcs-AC-D...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

Cheers!

Fish

#### Bluejets

Oct 5, 2014
6,197
Yes, as I suspected, non-isolated supply.
Refer to #4 and note the dangers.

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