Question for pull down resistor in S32K358

Changwoo82 — Thu, 04 Jan 2024 17:21:57 GMT

From the datasheet, 3.3V GPIO pull up/down resistance is 20 ~ 60kohm under condition like pull up @ 0.3 x VDD_HV_A/B, pull down @ 0.7 x VDD_HV_A/B.

Could I understand that minimum internal pull down resistor is 20kohm in all cases?

I'm sorry that I can't understand that condition.

Thank you.

Re: Question for pull down resistor in S32K358

lukaszadrapa — Fri, 05 Jan 2024 12:32:55 GMT

Hi @Changwoo82

This specification is valid only for mentioned conditions, so it can slightly vary at different conditions. The pull up/down device is emulated by a FET transistor on the chip. On previous devices, it was usually specified using pull up/down current flowing though the FET, not by resistance. But you can still expect values around those 20-60k.
Anyway, considering the worst case 60k, it's highly recommended to not rely on internal pull up/down when it is needed. For robustness, it's recommended to use external resistors 4K7 - 10K, especially in noisy environment.

Regards,

Lukas

topic Re: Question for pull down resistor in S32K358 in S32 Design Studio

Question for pull down resistor in S32K358

Re: Question for pull down resistor in S32K358