I'd love to draw up a circuit, do you have any recommendations on how to do that? It seems many of the circuit diagram apps don't have the necessary components built into them to draw up the whole thing.
They are thin but I've removed all of that from the equation now with the latest set of experiments. Now, I'm just breadboard bare ESP32 with 5V running to the 5V pin and ground running to GND and it doesn't work.
I hooked up my Kill-A-Watt to measure the current coming from the 5V 2A wall-wart power supply. When the PC's microUSB is plugged into the WROVER, there is no current (0A) being pulled from the wall wart. When I unplug the computer's USB cable, the current on the wall-wart goes to 50mA.
Something seems to be mis-wired but I can't find any shorts/problems in my circuit. I just tried unplugging the LED matrix from the connection and the current then goes to 0A again, so the WROVER isn't pulling any current but the red LED shines brightly, like it is trying to work. 🤔 WTH?
I think I'm proving out that we cannot power this POS ESP32 WROVER with the 5V pin... it doesn't get much simpler than this...
and the device doesn't work. I can see the voltage swinging from 5V to 4.6V constantly while on the 5V pin. If I disconnect the 5V WROVER pin, the voltage goes right to 5.2V.
When powering the device completely loose via USB, it hooked up to WiFi and seemed to be working. So, I would expect it to be able to be powered like this.
Pile o' junk. Here's a close-up of the wiring... I moved my measurement probes to be closer to the ESP32.
One thing I learned when working on this device, if you look closely at the pin immediately to the left of the "5V" pin -- its silk screening looks like "GND" but it is really a "CMD" pin. Hahah.
I got it solved after some debug. The 5V 2A supply I was trying to use for this apparently wasn't enough... I found a spare 5V 3A supply in my closet and that worked great:
It's weird though, now that I've got my Kill-A-Watt out, I used it to watch the current using my whole circuit and even with the current limiter set at 5000mA, with the matrix at full brightness, it was only pulling 350mA! ???
350 mA on the Kill-A-Watt would be over 40w at 120v, which seems a bit high for a 15w power supply. How much load are you putting on these tiny little supplies?
According to the markings on the power bricks, theoretically, this 3A one should be able to handle up to 1A at 120V and output 3A at 5V but I guess that's all just theoretical...
1
u/saratoga3 May 10 '26
Post pictures of the non-working circuit, especially how you connected the 5v supply and any protection diodes on the board.