BQ76952: The alert pin allows the MCU to wake up

Cherry Zhou

Part Number: BQ76952

Hi team,

The customer wants to wake up the MCU by interrupting the MCU through the alert pin. When exiting sleep, the alert pin signals an interrupt, but after exiting and entering sleep, the alert pin always outputs a high level with no change in signal.

The alert pin config is set as shown in the figure below, the alert pin is connected to 3.3V as recommended by the EVM with 10k pull-up:

Could you help check this case? Thanks.

Best Regards,

Cherry

over 1 year ago

0 Arelis Guerrero over 1 year ago

TI__Expert 4465 points

HI Cherry,

As you mentioned you have an external pull-up to 3.3V, my best guess is that you want to configure the ALERT pin as a open-drain output. Can you change the ALERT pin configuration to 0b00100010 and re-try.

Regards,

Arelis G. Guerrero

0 Cherry Zhou over 1 year ago in reply to Arelis Guerrero

TI__Mastermind 22235 points

Hi Arelis G. Guerrero,

Thank you for the support.

Arelis Guerrero said:
change the ALERT pin configuration to 0b00100010 and re-try.

Could you help elaborate more on the "0b" of 0b00100010?

Also, how to set the alert pin to signal an interrupt when only exiting/entering sleep?

Thanks and regards,

Cherry

0 Arelis Guerrero over 1 year ago in reply to Cherry Zhou

TI__Expert 4465 points

Hi Cherry,

"0b" means binary notation, similar to "0x" means hex. We want to set the register to binary (00100010) or hex (22). Then re-try and let us know if that solved the behavior you are observing.

Regards,

Arelis G. Guerrero

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BQ76952: The alert pin allows the MCU to wake up