Regarding VOL voltage at various IOL currents

[AkshayMR]

We are using a GPIO pin in STM32H743IIK6 microcontroller in open drain configuration. In datasheet, it is mentioned that Vol = 0.4V at IIO = 8mA and Vol = 1.3V at IIO = 20mA. What will be the Vol voltage at currents higher than 10mA? How does Vol vary with respect to IIO?

[Michal Dudka]

The values ​​you specify are maximums (!) and typicaly will be much lower. Connect few resistances as load to output pin and measure real values, also for desired 20mA.