Reset hold

[lyingying]

The S32K146 calls the software reset interface （function  ：NVIC_SystemReset();）， MCU crash   fortuitously One in ten thousand approximately，Measure the reset pin keeps pulling down and does not connect the MCUS32K146 by PE emulator ;As described in the application notes(AN13461) on the official website   ;But I don't understand how to deal with this problem,what is SiR in this document,How to solve SiR problem.What reason Lead to Reset pin keeps pulling down,We just called the reset function seldomly in work code.

We did the following validation test: The reset function is called every 1.5 milliseconds,It was tested on 20 test board simultaneously,It lasted just one day ,4 test board appeared  MCU crash,    Reset pin keeps pulling down,  can not  attach to running target,We're out of options. Call for help!!!

[lukaszadrapa]

Hi @lyingying 

Did you check the waveforms of rising voltages and reset signal during the startup by an oscilloscope? Is there anything unusual on failing parts? Is it possible to share some screenshots? Is it possible to share the schematic for review? I’m not interested in whole schematic, only in power supplies, decoupling, reset circuit etc…

Regards,

Lukas

[lyingying]

I grabbed it with an oscilloscope，When the fault occurs, The reset pin has no waveform，Just power it back on，Then continue the reset test，Sometimes it comes back in a day and sometimes it comes back in a week。

what is zhe waveforms of rising voltages?The test is a continuous power test,There are high and low level changes during normal reset test,but it can't get up when it breaks down.

failing parts:MCU not working;The measuring crystal clock is not vibrating,Measuring current 5.69MA,Power supply Normal 12V;The MCU 5V power supply is normal;The reset pin is pulled down; 

[lukaszadrapa]

I'm sorry for delayed response. Did you try to do A-B-A swap test? It's weird behavior, I can't see a reason for this. If the A-B-A swap test that the failure follows microcontroller, I would recommend to send the devices for failure analysis.
Regards,
Lukas