[sdiy] Best way to get a +3.3V rail from +15V?

[Stewart Pye]

Use something like this:
http://www.murata-ps.com/data/power/oki-78sr.pdf

We use the 5V version in several products where I work. I'm on holidays 
and can't remember where we purchase them, but they cost around AUD $2. 
We have dropped them in to PCB's designed for 7805 regulators and they 
work fine...

3.3V, 1.5 amps at 85% efficiency, no heatsink. Woot woot!

Regards,
Stewart.



On 3/7/2013 11:07 PM, Tom Wiltshire wrote:
> Hi all,
>
> I'm putting a little dsPIC prototype dev board together for mucking about on. I've done such things before, but I've always had a +5V supply available, so when I've needed a 3.3V rail for the dsPIC, I've stuck a regulator on the 5V supply. Which was fine, but that's not the situation this time.
>
> If I've only got +/-15V available, what's the best way to derive a 3.3V rail?
>
>
> I've used 3.3V regulators on the 15V rail before and found they got hot, which wasn't a surprise seeing how much voltage they've got to lose somewhere. But perhaps I was doing something wrong?
>
> Thanks,
> Tom
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>