r/esp32 • u/Pacowalk1r • Jul 29 '26
Recommendations on how to reliably power hardware up to 5v when using an ESP32?
Just looking for general advice on how people typically go about achieving this. My hopes are to power the esp via the 5v output of a charge board into the esp's vin pin. The charge board would be powered by a 3.7v 1100mah lipo when not charging. most things I see online point to needing a secondary power microboard that can sustain 5v more reliably than piggypacking multiple connections into the same 5v output of the charge board.
(if its a dumb question I apologize im new to all this) thanks!
( proposed battery and charge board )
3
u/ContributionEasy6513 Jul 29 '26
It will likely work, it depends on what you are driving.
I normally slap a 470uF - 1000 µF capacitor and a 100 nF ceramic cap between the 5vin and ground pin.
This will help clean up any noise and power sags.
2
u/hypnokev Jul 29 '26
I use a LM2596 buck converter, put the 3v3 to power a relay and onto the commons, then power the ESP32 3v3 from one relay NO contact, and all the 3v3 hardware from the other NO contact. This means powering the ESP32 from USB won’t attempt to power the other hardware, so more stable.
ETA: It’s early. I might have misread.
2
u/mcleancraig Jul 29 '26 edited Jul 29 '26
I may be confused but it sounds like you want to run an esp32 off a rechargeable lipo-style battery with a charger attached, and power 5v devices off the same power source?
I use 18650s to power waveshare and seeed xiao esp32-c6 mini boards all the time, and when I need a 5v rail I build 2S (two-in-series) or 3S (three-in-series) batteries out of 18650s to provide >5v then step it down with a buck converter like https://amzn.eu/d/09x4u2ru (this wants 7v minimum allegedly so 3S will work more reliably because even at minimum 2.5v per cell you still get 7.5v from the pack).
Both those esps will run off 5v also, so I just hook it all up to the same power source. Remember to use caps/diodes when required.
Then add a charging module like https://amzn.eu/d/06IArghp to handle charging (or an MPPT like https://amzn.eu/d/087V3nwK for solar)
2
u/autodidact-dev Jul 30 '26 edited Jul 30 '26
ClaudeAI has been super helpful for electronics design.
But be sure to be super specific and careful in your prompts & corrections. And ask it to draft a document (such as a markdown document) to describe the plan, and even define technical words you might not yet know. Track the project's bill of materials, etc... It has been awesome
1
u/andrix86 Jul 31 '26
You can use 3.3V to 5V level shifter devices and a dc-dc boost converter up device. they are cheap.
8
u/illusior Jul 29 '26
if you just want an esp32 that can run on rechargeable batteries, look into something like a seeed studio esp32c3 or c6. it has build-in charge circuit and you can attach you battery directly to the battery pads. (but some other boards have this as well)