Undershoot tolerance at STM32F767IIT6

[Tomas Bengtsson]

Posted on May 15, 2018 at 15:10

1. Does STM32F767IIT6 tolerate an undershoot of -0.8V lasting for 2ns at a 5V tolerant I/O?

[T J]

Posted on May 15, 2018 at 15:55

maybe, only because the 2nS is not enough time to overheat anything.

You could divert that energy by using a schottky diode from ground on that pin, clamping to -0.4v max

[Imen.D]

Posted on May 15, 2018 at 15:57

Hello

tomas.bengtsson@prevas.se

,

For the Input voltage on FT pins:VSS − 0.3V ; with maximum:VDD+4.0V

For more details, please check therelated

http://www.st.com/content/ccc/resource/technical/document/datasheet/group3/c5/37/9c/1d/a6/09/4e/1a/DM00273119/files/DM00273pdf/jcr:content/translations/en.DM00273pdf

,in the Table Voltage characteristics

Noted that V

IN

maximum value must always be respected. You should refer to Table 16 for the values of the maximum allowed injected current.

Best Regards,

Imen.

[AvaTar]

Posted on May 15, 2018 at 16:07

maybe, only because the 2nS is not enough time to overheat anything.

This depends on the actual circuitry 'behind the pin', I would be cautious.

MOSFETs, for example, have a dV/dt limit. Exceeding that limit will kill it, without much energy involved (relative to it's total admissible power dissipation). I've seen FETs dying that way.