topic S32K312 watchdog timer in S32K

S32K312 watchdog timer

mogilipuri_harish — Thu, 23 Mar 2023 07:53:29 GMT

hello team,

we are using S32K312 uc we are not using SBC ic and we are powering with LDO. so should we use any external watchdog timer. can you please tell me the if we are not using the SBC can we meet the functional requirements (ASIL-B)??

Re: S32K312 watchdog timer

petervlna — Thu, 23 Mar 2023 08:49:57 GMT

Hello,

Well this is a question for your safety expert.

In general, when you need to reach any safety class, you should ensure that in case of voltage loss/drop the device will react properly to that event.

If you do not have SBC with watchdog, I guess you have some supervisor unit monitoring and powering this ASIL-B device.

Best regards,

Peter

Re: S32K312 watchdog timer

mogilipuri_harish — Thu, 23 Mar 2023 10:08:26 GMT

s32k312 we need to connect any external watchdog timers or internal watch dog timer will take care when uc is timer is in timeout state?

we need to connect any external watchdog timers can you please suggest the part no?

Re: S32K312 watchdog timer

petervlna — Fri, 24 Mar 2023 08:48:06 GMT

Hello,

s32k312 we need to connect any external watchdog timers or internal watch dog timer will take care when uc is timer is in timeout state?

The internal watchdog will guard code execution, theres is no issue.

But I expect that for ASIL-B external watchdog is required (in order to backup internal one). Please consult it with your safety expert who exactly know what is ASIL-B requesting, or with certification company.

External watchdog can be also any supervisor unit, like other uC.

we need to connect any external watchdog timers can you please suggest the part no?

[Peter] - I do not have any recommendation, But basically any watchdog on serial bus is fine.

Best regards,

Peter