STLink V3 Mini becoming hot when connected to USB

[SSaha.1]

I got a STLInk V3 Mini board from mouser. When I connect the board to the computer via USB, the board becomes hot (without connecting anything to the programming header pin). When I do connect the target board to the Mini, the Mini stops identifying the board after some time (probably due to heat).

Is the Mini board faulty?

[Uwe Bonnes]

That is normal. The F723 is a powerfull chip needing some current . The board is small and so a lot of temperature is needed to get rid of that heat.

[SSaha.1]

The board stops working when it heats up :\ That's not normal is it?

[Uwe Bonnes]

The board not connected to a target should not stop working. I suspect you connected a target in the wrong way. Be more specific? Did the board stop working with or without target connection. Does is work again when target is unplugged? Does it work again when cooled down? Can you measure temperatures, e.g. with pyro camera?

[SSaha.1]

The board was becoming hot even before I connected to the target. I then connected it to the target. The setup worked fine for ~ 10 mins (I could upload programs to the target and observe data flowing in and out of serial) before the board refused to detect the target anymore. After cooling down, the board again detects the target but stops working after few minutes.

[SSaha.1]

As per connections, here's how I connected the target to the board (reference: https://www.st.com/resource/en/user_manual/dm00555046-stlinkv3mods-and-stlinkv3mini-mini-debuggersprogrammers-for-stm32-stmicroelectronics.pdf (Page 19))

Board (STDC)/Debugger/Programmer - Target (stm32l476rg mcu):

1 -

2 -

3 - VCC (3.3V)

4 - PA13

5 - GND

6 - PA14

7 - GND

8 - PB3

9 -

10 -

11 - GND

12 - NRST

13 - PA3 (serial)

14 - PA2 (serial)

[LBeau.1]

I have 2 of these debuggers and 2 of the ST-LINK V3 mini, they have stayed connected for days and never got hot.

Either your board is wrong or the debugger is wrong. Seems like your connection is wrong.

I stay with the cortex mini header 10 pin 1.27mm SWD, pullup on SWO and NRST

[SSaha.1]

I have used the same connection between the STLink breakout that comes with Nucleo boards and target boards, did not have any problem. PA13 is the SWDIO, PA14 is the SWCLK and PB3 is the SWO on STM32L476rgt6 MCU. I also have pull up on NRST. The serial connections are fine too as data comes in and out.

[LBeau.1]

You think you have used the same... These things happen all the time.

I guess its your proble to fix and there is indeed a malfunction as it should not get hot.

Get another debugger and see...maybe.

[SSaha.1]

This is very weird. I got a brand new STLink debugger from mouser. I have not connected anything to the debugger at all and just connected it to my macbook via usb. It's becoming hot automatically. Repeat: I did not connect any board to the programmer I just connected the debugger to the computer via micro USB cable.

I am buying all these debuggers from Mouser: https://www.mouser.com/ProductDetail/STMicroelectronics/STLINK-V3MINI?qs=mAH9sUMRCtvrXm%2FF%2FC0CYg%3D%3D

This points something is wrong with these debuggers.