Solution Finder Get Tech Support

3.3v @ 20ma line power supply

Posted by: wm77 on

Hello,
I need a power supply with a 3.3v/20ma output. Or maybe the output can be higher and I can put a post regulator to get it down to 3.3V. I already have a bridge on the AC line (85-265VAC) available so I would like it to connect to the bridge output that's already available.
What part would best fit this with lowest cost and efficiency as the important criteria.

Thanks

Comments

Submitted by Tim Starr on 03/17/2010

If you do not need isolation, a LNK-TN part would work very well in a buck configuration.

If you need an isolated supply the LNK-CV family (in a flyback topology) would be a good fit. These are both low cost solutions.

Hope this helps!

-Wesley

Submitted by wm77 on 03/18/2010

It will not be isolated. It looks like this part will be a good fit.
I looks like I can just scale R1/R3 to scale down the 12V to 3.3?

Thanks

Submitted by Skywalker on 03/18/2010

Since it is such a low output power, LNKLP would be the right device family.

The smallest device, LNK562D, will be good enough for your application.