ESP32C3 super mini USB dropping on external power connection
Posted: Sun Dec 07, 2025 7:24 pm
Hello,
I have an issue with a project based on an esp32C3 super mini board.
My project has 3 stepper drivers and therefore an external power supply.
But it also needs a PC connection through the USB cable.
The problem is that, very often, but not all the time, when I connect the power to the board, the USB connection drops (I can hear the USB out windows sound).
Depending on the power source, I might not even be able to get any USB connection..
Can you help me fix this issue?
This is my main schematics.
This is a zoom on the ESP32C3 + power area.
The USB connection to the PC is optional. External 9-20V power is compulsory to drive the motors.
To allow the esp32 board to run from the "external" power when there is no USB, I have placed an ali-express DC-DC board to get 5V from this to power the ESP32.
Link to the DC-DC: https://fr.aliexpress.com/item/1005006308573192.html
Schematics of the ESP board:
Cyrille
I have an issue with a project based on an esp32C3 super mini board.
My project has 3 stepper drivers and therefore an external power supply.
But it also needs a PC connection through the USB cable.
The problem is that, very often, but not all the time, when I connect the power to the board, the USB connection drops (I can hear the USB out windows sound).
Depending on the power source, I might not even be able to get any USB connection..
Can you help me fix this issue?
This is my main schematics.
- pcb1.png (177.48 KiB) Viewed 4402 times
The USB connection to the PC is optional. External 9-20V power is compulsory to drive the motors.
To allow the esp32 board to run from the "external" power when there is no USB, I have placed an ali-express DC-DC board to get 5V from this to power the ESP32.
Link to the DC-DC: https://fr.aliexpress.com/item/1005006308573192.html
- pcb2.png (105.4 KiB) Viewed 4402 times
- esp32-c3-supermini-schematic.png (316.22 KiB) Viewed 4402 times