STM32f303

[DianaSok]

In 50% of the PCB s where the STM32f303 (with the Y revision ) was in we were unable to code a program , as well as that problem we had some difficulties with the UART It won’t connect to the laptop, it says that the device is unrecognizable and that it does recognize the COM port.
In the picture down below you can see the unstable signals (they are marked)

[Peter BENSCH]

Welcome @DianaSok, to the community!

What exactly do you mean by "unable to code a program", i.e. what do you want to programme and what errors occur?

Which program on your laptop returns the error that the device is not recognisable?

What do you mean by unstable signals, or what signals do you expect?

Regards
/Peter

[Tesla DeLorean]

Sorry, your presentation of the problem isn't terribly helpful.

We're Non-Y parts less problematic? Did prior batches of boards work?

What does "unable to code a program" mean? That the download failed? That the verify failed? That the code failed to run at startup? You're going to have to be a lot more specific and detailed in your observations..

Add some output telemetry for Error_Handler, HardFault_Handler and clock speeds and status.