Output voltage characteristics of STM32G070CB

[Kraal]

Hello folks,

I can't figure out the meaning of table 48 p.64 of STM32G070CB datasheet (see attached picture). In particular the FT_c pins. Page 63 it is written that all I/O can source up to +-6mA and +-15mA with relaxed VOL and VOH.

Back to table 48, FT_c pins can have +-2mA or even +-1mA Iio as conditions, but I fail to understand the differences between the lines (1 & 2) and lines (7 & 8).

Pratical case: if I want to use PD0 (FT_c) to generate a PWM to drive a MOSFET, what will be the maximum current output of this pin ? Vcc is 3.3V.

Thank you very much,

Kraal

[Bubbles]

Hello @Kraal​,

it's not obvious, but not too difficult either. lines 1&2 are under condition VDDIO > 2.7V. The lines 6&7 are for lower voltages, basically starting at BOR voltage threshold.

BR,

J

[Bubbles]

sorry I meant 7&8 of course

[Kraal]

Thank you @JHOUD​ for this clarification.

Now regarding the practical case, what is the output current of FT_c pins in PWM output when driving a MOSFET ?

Best regards,

Kraal

[Bubbles]

Hi @Kraal​,

that only depends on the load, which is the MOSFET in this case. I'm more SW oriented, but from what I remember the MOSFET gate is controlled by voltage, not current. I expect the gate impedance to be pretty high. Check the DS of the MOSFET you want to use, or run some simulation if model is available.

BR,

J