BQ76PL455A-Q1: How to check fault source and how to wake up after powering up

Miles Li1

Part Number: BQ76PL455A-Q1

Hi team,

I have two urgent questions that need your help:

1. When two 455 are using daisy chain in one board(one is connected to MCU), how should we wake up both device after powering on from powering off?

2. If falut_n is low and, both STACK_FAULT and STACK_FAULT_DET are read"1", how should I know where the fault is from? I need to find the source.

WIsh to get your reply, thanks!

over 4 years ago

0 Taylor Vogt over 4 years ago

TI__Genius 17370 points

Hi Miles,

1) The second device wakes up via a wake tone sent via daisy chain from base device. Search 'wake tone' in the datasheet to see if this helps.

2) This thread should address your concern: https://e2e.ti.com/support/power-management/f/196/p/816138/3027093?tisearch=e2e-quicksearch&keymatch=bq76pl455a%20stack_fault#3027093

Regards,

Taylor

0 Miles Li1 over 4 years ago in reply to Taylor Vogt

TI__Intellectual 1640 points

Hi Taylor,

Thanks very much for your reply! #2 answer is very helpful, but I wonder why low-frequency heartbeat occur? Hareware circuit or software configuration issue?

Wish to get your further answer.

Thanks!

0 Taylor Vogt over 4 years ago in reply to Miles Li1

TI__Genius 17370 points

Hi Miles,

It could be several scenarios but likely it could occur due to EMC noise, BCI (bulk current injection), or internal issue with the clk.

Regards,

Taylor

0 Miles Li1 over 4 years ago in reply to Taylor Vogt

TI__Intellectual 1640 points

Hi Taylor,

Do you have any suggestion on how to solve this question?

0 Taylor Vogt over 4 years ago in reply to Miles Li1

TI__Genius 17370 points

Hi Miles,

Did you see my response above? What is missing? i think this is the most detail we can provide on this topic.

Thanks,

Taylor

0 Miles Li1 over 4 years ago in reply to Taylor Vogt

TI__Intellectual 1640 points

Hi Taylor,

Got it. Thanks!

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BQ76PL455A-Q1: How to check fault source and how to wake up after powering up