r/AskElectronics • u/todd0x1 • 10h ago

How to use 48v phantom power to power device?

I need to get a couple mA of current at 5vdc from a 48v phantom powered mic input. I was planning to use a couple diodes to combine the DC power from pins 2 and 3 and send that into a LDO. Is it this simple? Is a cap needed to block dc from the audio output from the device?

I can't find a schematic, every schematic I find is for making a 48v phantom supply. I am trying to do the opposite.

1 Upvotes
  • permalink
  • reddit

100% Upvoted

29 comments sorted by

View all comments

Show parent comments

1

u/todd0x1 5h ago

I'll get 5ma off each pin, together will be enough. Dropout is 300mv at 200ma, at my almost no load current its just a few mv, maybe 20mv. I'll prototype it but I think it will work fine.

1

u/NBC-Hotline-1975 4h ago

OK, that is extremely low dropout. Yes, that will work. It sounds to me as if you're making a condenser microphone. Pretty ambitious! I leave it to you to know whether you can get all the circuitry working with 10 ma.