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

[Steve Ridley]

> And this is much simpler than a switching solution.

Simpler? Try Traco TSR series or XP Power SR range devices. 

- Similar footprint to a TO220 (not smd - old folks can see them)
- Small part count - add two caps and a small inductor
- >90% efficient so barely warm - no more "ouch! (insert expletive here) moments when you touch it.
- no clumsy heatsink cluttering up your development board
- At 200mA out it'll draw less than 50mA from the 15v.


Complicated? Linear:

- Juggling heat dissipation across two devices in non-free space
- Mounting heatsinks so they don't get in the way, burn you or take up acres of space
- Deal with uneven load your +/-15v supply
etc.

Worth a try?


Steve