what is the minimum circuit i need for a STM32 to run it and debug via SWD? Is the attached schematic sufficient? For debugging I would connect my J4 to CN4 of a Nucleo board. Sorry for the trivial question, i don't have much experience with stm32

[BKarl]

[Tesla DeLorean]

Yes, looks pretty good, I think it achieves what you set out to do.

Might want to add the 32.768 KHz crystal, most STM32 turn all the other clocks off in STANDBY operation. Check the diagrams for the Low Power Domain. PC13,PC14,PC15 have very low drive currents as they are in that domain.

[BKarl]

ok, happy to hear that, thanks for the quick answer

[S.Ma]

If Vdd is like 1.8V, check the debug probe capability for supporting lower voltages.

[BKarl]

Vdd is 3.3V, is that a problem if I want to use a Nucleo-board for debugging?

[Danish1]

As you don't show how power gets to the board (and no sign of a voltage-regulator), it might be that you're powering it from a bench power-supply (or some other voltage source) or the nucleo board, on the end of "long" wires (let's say longer than 20 cm).

If that's the case, I'd want more power-supply-decoupling - a single big capacitor 10 uF to 100 uF between Vdd and ground. (If you use a tantalum or electrolytic, be sure to get the polarity right.)

[BKarl]

ah ok i see what you mean, yes i took that into account (I hope so). This is how the power gets to the board: