power supply options with output 5V

All ESP32 boards running MicroPython.
Target audience: MicroPython users with an ESP32 board.
Post Reply
ajocius
Posts: 81
Joined: Mon Feb 19, 2018 6:31 am

power supply options with output 5V

Post by ajocius » Tue Feb 11, 2020 7:20 pm

I have powered Wemos Lolin 32 ESP32 board via power supply (not USB) with 3,3V. I understand USB power input would be 5V, but on power input (which is separate connector) I need to supply 3,3V. Here is my board:
https://wiki.wemos.cc/products:lolin32:lolin32

Question, is it possible to use 5V connector (left side second bottom one, next to GND) to get 5V out which I need to power relays? There is 5V connector on this board, however it does not provide 5V in my case. Should I enable it via micropython command? Or is it only available if board is powered via USB 5V input?

I have 5V relays ant those work only sometimes when powered with 3,3V, so need to find another solution.

User avatar
jimmo
Posts: 1700
Joined: Tue Aug 08, 2017 1:57 am
Location: Sydney, Australia
Contact:

Re: power supply options with output 5V

Post by jimmo » Tue Feb 11, 2020 10:23 pm

Yeah that 5V pin is likely just connected to the USB voltage. The board very likely won't have an internal way to generate 5V from 3.3V.

A tiny boost converter is pretty easy to get. Adafruit have them as modules for powering USB devices from lipo batteries.

ajocius
Posts: 81
Joined: Mon Feb 19, 2018 6:31 am

Re: power supply options with output 5V

Post by ajocius » Wed Feb 12, 2020 3:53 am

Can I power ESP32 via that 5V pin instead of using 3.7V power connector socket? This would be simpler solution in my project if it is possible. As I am already using down converter from 12V down to 3.7 to feed ESP32. So instead of adding boost converted in order to get 5V, I could instead adjust 12V down to 5V and feed ESP32 via 5V pin as well as have 5V for my relay?

User avatar
jimmo
Posts: 1700
Joined: Tue Aug 08, 2017 1:57 am
Location: Sydney, Australia
Contact:

Re: power supply options with output 5V

Post by jimmo » Wed Feb 12, 2020 4:25 am

ajocius wrote:
Wed Feb 12, 2020 3:53 am
Can I power ESP32 via that 5V pin instead of using 3.7V power connector socket?
Looking at https://wiki.wemos.cc/_media/products:l ... v1.0.0.pdf that looks fine.

Post Reply