STM32WB5 unable to connect

[vmcasadoz]

Dear Sirs,

I have been developing a board with an H7 and a WB5. I have not had any issues, but one day the WB5 stopped answering, and when I try to connect with the CubeProgrammer I get: "no stm32 target found if your product embeds debug authentication".

I moved to a new board wight out of the box, without luck, I changed from the STLink V2 to a new bought STLink V3, no luck.

At this point I do not know what to try, because I have already validated my custom PCB as I have it already running and it just lost the communication one day, and with a completely new board (because I thought I could have reflashed the SWIO/SWCLK pins or something to different pins) it does not work either.

One point to mention , is that the CubeProgrammer detects the Target Voltage at 3.23V.

I have updated both STLinks to the last FW versions that the updater tool allows.

I tried too by setting the BOOT0 pin to 1 so it boots in the default bootloader.

What could I try? Am I missing something? Has something been updated?

Thank you so much in advance,

Best regards

[TDK]

If it was working, and no longer is, and nothing that you know of has changed, it's likely something happened to the hardware. Perhaps ESD damage. Perhaps a pin became free due to a manufacturing defect. Perhaps a defect in the design finally cause the chip to fail.

Check power rails and power pins for relevant voltages. Show schematic. Check connections between parts.

Sounds like you have an H7 board on hand. That should be enough to verify the programmer is working.

[vmcasadoz]

Hi, but I got a new set of PCBs fabricated, and also with other boards and all the WB5s fail.

yes I can program and debug any other STMs, for example the H7 on the same board is working fine, also I bought the Datalink V3 to try and it does not work.

Here I attach the schematic.

Thank you so much for your help!

you!

[TDK]

Are all of your VSS pins connected? Only one is shown in the schematic.

[vmcasadoz]

Hi,

this is the actual layout:

Thank you!