STM32F4 A/D Input Bias Current

[David Ashman]

I'm not able to find a spec in the STM32F446 datasheet for minimum A/D input bias current. Does anyone know where I can find this info? I need to sample the voltage from a high resistance potentiometer and it would be handy to know if I need to buffer prior to connecting to A/D pin. Thanks!

[waclawek.jan · Accepted solution]

Static current is given by

 

But this is never the limiting factor.

This is:

The ADC input is a switched capacitor,, and you have to ensure it is fully charged to input signal's level during the sampling phase of conversion.

JW

[David Ashman]

Thank you @Community member​ This is very helpful.