ESP32 Forum

Hello,
i have made a diy board using ESP32-C3 chip. I populated one and have it working perfectly. I populated a second one, identical to the first, but when i plug it to my windows computer the usb connection does not work. The board gets power but from the computer side it is like if nothing was connected.
I have spent a lot of time checking the connections pin by pin, and the only differences i notice is that the board that works well shows a voltage of 3.3V in both Chip_en pin (pin 7) and VDD_SPI pin (pin 18) while the one that doesn't work shows only 0.4 volts in those 2 pins.
Any clue what might be happening there? i have tried everything but nothing seems to work....

thanks a lot for any tip.

Hard to say without having the physical thing on hand, but it feels like the CHIP_EN is shorted to ground somewhere, or at the very least isn't pulled up to 3.3V. That would also result in VDD_SPI not coming up. I'd suggest looking at your reset circuit first, and perhaps try to reflow the ESP32C3 chip second.

thanks Sprite,
no, it is not shorted to ground, it must be something else

CHIP_EN MUST be driven high by your board. If it's not high, you must figure that out first. Normally, that's a pretty simple circuit (a pull-up resistor, and probably a reset switch). If that pin is not at 3.3V, nothing is going to work.

sorry guys, my bad, it is not chip_en that reads only 0.4V, it is the boot pin (pin 15) and as mentioned VDD_SPI pin (pin 18).
chip_en is not shorted to ground, i read 319 KOhm resistance between that pin and ground.
sorry for the confusion.