I have soldered very simple project on nano v3 includes i2c oled 128x32, pushbutton with certain sequence to change display data and isolated optocoupler used as 220 to 5V adapter (the project should count numbers of connections to 220V). When I power it from USB it works fine. But I need to power…

Works fine powered from USB works bad powered externally

ilyagin November 12, 2021, 6:21pm 6

Yes but I need to stay the USB port available in this project.

Topic		Replies	Views
Arduino stops working when connected to an external power supply IDE 1.x	5	1652	May 5, 2021
USB Problem with Arduino Nano 3.0 With External Power Applied IDE 1.x	9	13981	May 5, 2021
Power problems Frequently-Asked Questions	13	5211	May 6, 2021
Arduino NANO ATMEGA 328 IDE 1.x	9	2534	May 5, 2021
Measured voltage, Nano v3 dies, cannot power/IO via USB. IDE 1.x	17	3209	May 5, 2021