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No 3.3V regulators on hand, can I — Parallax Forums

No 3.3V regulators on hand, can I

Problem with a prop mini I think, but need to test with another prop to be sure. so went to build up a prop on the 4 row breadboard and can't find a 3.3v regulator. Here somewhere....

So, I linked 3 diodes series for an output of 3.34V. If the drop across the diodes will always stay at 1.7v, does this seem like a reasonable solutionto run the prop? As a side question, if the former is reasonable, if my board is full of 5V ADCs, DACs, sensors and logic, would this be a lower cost way to power just the prop and its EEProm instead of having another three terminal regulator?

Thx

Comments

  • The diode stack reg. is just to old school for me, The LM78xx, LM79xx are easy and cheap. Thats my 2 cents
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2021-01-10 02:18
    For anything low current and in a pinch I just use a red LED. Sure, use the diodes, but only in a pinch. btw. regulators are dirt cheap, certainly under 30cents and the cheapest I found at Mouser for 1 off was 11 cents for a 300ma LDO (MIC5504-3.3YM5-TR). I'm sure LCSC would have some for 3 cents. Why except in a pinch would you bother with diodes!

    EDIT: LCSC have LDO regs at 50 for 89 cents.
  • Thanks Peter, this was actually an in a pinch question for now, so that was answered. As to the sources for the LDO, thx that will be good to know when I order up some more to use. The Frys aside from being 45 minutes away are open, but so picked over as to it being anyone's guess if one can be had there. Don't know why they just don't shut the things and be done with it.
  • Frank,
    I am a little closer but I agree though they certainly not in the components business.
    Jim
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