ESP WVROOM 32 Breakout not powering up

I have a bare ESP32 module (ESP WVROOM 32) soldered to a breakout board that I ordered from OSH Park and it appears to never power on. I’ve found multiple schematics and tutorials for powering a bare module, they’re all very similar but none are identical. I’ve tried them all with no luck.

I’m now trying to identify what my problem is, but I’m a bit stuck.

Here are some notes:

  • Using an external USB to UART programmer, I’m able to download a sketch to the module (at least the Arduino IDE tells me it was successful).
  • After removing the programmer connections and trying to power using just my benchtop supply, the module appears to do nothing. I simply downloaded the blink sketch and verified it’s working on a different ESP32 dev board.
  • I’ve checked my solder work by doing a continuity check on all pins to verify they’re connected and that there is no bridging of those small ESP32 pins.
  • The same attempt to power my ESP32 dev board works.
  • I have tried this with 3 different, identical breakout boards/ESP32 modules that I’ve made. They all exhibit the same problem.

I’m assuming that the dev boards have some other internal wiring that makes them power up unlike the board I soldered. But I haven’t been able to figure out what, if any.

This is the doc I used for my current wiring attempt.
https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf#page19

Attached is a pic of my project on a breadboard.

On those solderless breadboards the power rails are usually split in two at the midway point. Here’s a Paint showing roughly where.
It is likely the supply isn’t even getting to your board.
IMG_7219.jpg

Jasonchildress: After removing the programmer connections and trying to power using just my benchtop supply, the module appears to do nothing. I simply downloaded the blink sketch and verified it's working on a different ESP32 dev board

A useful troubleshooting tip;

When stuff you expect to work does not, check with a multimeter that you really do have a supply voltage (3.3V in this case) on the processor you are working on.

@BjHenry, My breadboard has solid power rails. I verified with my Multimeter.

@ srnet, I should have made it more clear in my original post that I did test all power connections with my multimeter to verify that the module is getting the proper voltage.

Some other information:

  • When powering the breadboard with 3.3v from my power supply, the breadboard’s power rail and 3.3v pin on the module read a lower voltage.
  • I’m assuming that breadboard’s rail and other components are introcuding some amount of resistance that is lowering the voltage before it hits the module’s power pin.
  • Even after increasing the power from my power supply until the module’s power pin does recieve at least 3.2v (which should be enough), the module still does not power on.

Its not clear from the photograph what you are showing us.

If your feeding 3.3V into the breadboard and the ESP32 is getting only 2.68V, you could have a serious problem.

Disconnect the power and sort the problem out.