Hi,
I have built a handful of STM32 designs before and never had a chip fail to connect. I can't seem to get any connection in Cube Programmer at all:
- VDD,VREF+,VBAT is at 3.3V, VSS is connected to ground.
- NRST is high at boot
- I can see current drop from 17mA to 7mA (at 12V) when pulling NRST low , so it seems like MCU is doing something.
- I originally connected with a JLINK but just bought a STLINKV3 SET with the same result.
- Using SWD over a tag connect
- tried every connect option in cube programmer (mode/reset mode)
- I see SWCLK,SWDIO, and NRST working on an oscilloscope, although I haven't bothered decoding the signals.
- I confirmed chip orientation
- I confirmed SWCLK,SWDIO, and NRST pins
- I confirmed my STLINK was updated
- Checked for shorts under microscope
Schematic:
Layout:
I am pretty much out of ideas at this point, hoping its something *** I missed and need a second set of eyes :)
Any new ideas would be appreciated!
