Error Output On the S32KK144 MCU

[gururajtalewad]

Hi

I am referring to the Functional safety manual (“S32K1xxSM_Rev6.pdf”) shared with us for s32K MCU family. In context  to hardware requirement, the manual suggest to have error output from MCU to connect it to external IC as shown in the fig 4-1 (Functional Safety related connection to External Circuitry).

Could you please clarify which peripheral pin is referred here as Error Output in MCU. I could not able to find Error output details in the pinmux sheet or Reference manual. Kindly clarify on the same. We are using FS32K144HAT0MLHT (32BIT 512KB FLASH 64LQFP) part in our design.

Let me know if any more information required, looking forward to hear from you soon.

Regards,

Gururaj T

@yosoytono 

[nxf69503]

Hello Gururaj,

The Functional safety related connection to external circuitry is explained in the detail in chapter 20 -External Watchdog Monitor (EWM) of S32K1xx Series Reference Manual, Rev. 13.

The EWM signals are available in Table 20-1. EWM Signal Descriptions and the pin mapping for these signals are available in the Pinout,  IO Signal Table, Input Muxing and PeripheralSummaries sheets of S32K144_IO_Signal_Description_Input_Multiplexing workbook.

Thanks & Regards,

Sanghamitra Pradhan

[gururajtalewad]

Dear Sanghamitra Pradhan,

Thank for the clarification on the topic. I have understood the strategy to be used now for apply the error output.

Thanks for the support.

Regards,

Gururaj

[jinjingyang]

Hi, @gururajtalewad 

There is no fault output or error output pin on S32K1. There are such pins on S32K3 or MPC57xx.

(The FCCU module has two pin output to an external SBC which monitors MCU status.)

If such pin is needed in some applications, I would suggest using a safety SBC which includes a watchdog. The MCU should refresh the SBC watchdog through SPI and this watchdog is windowed watchdog and challenger watchdog. When there is error on watchdog refreshing, the SBC will control its safe output pin. Thus the MCU plus SBC as a whole has an error output which can be used to turn off some driver IC or turn off some switches, communication interfaces, and so on.

[gururajtalewad]

Dear Jason Yang,

Thanks for the suggestion and clarification. I am using the UJA1169 SBC in my application. Is this device a safety SBC?

Or do you recommend similar device? Thanks for the support.

Regards,

Gururaj.

[r40959]

Dear Gururaj, the UJA1169 is not developed according to ISO26262. We recommend to use instead FS45/65/84/85 ASILB/D devices. They include FCCU monitoring functions to monitor MCU error signals. Best regards