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
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
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.
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