BQ25155: BQ25155 reset button behavior

Riccardo Gaiati

Prodigy 70 points

Part Number: BQ25155
Other Parts Discussed in Thread: BQ25150,

Hi,

i would like your feedback about this scenario with BQ25155 or BQ25150.

As reported in the manual:

it seems that we can change the reset behavior.

In our project, the bq25155 is configured at the boot up in such way to generate an hw reset after 14 seconds.

Under some specific condition (battery voltage very low), I want to disable this behavior, by having no action after 14 seconds (see the picture below).

I ran some tests in these conditions:

Preset:

- battery voltage is very low (< 2Volts);

- VIN present;

Observation:

- the button MR is always detected as low;

- the hw reset keeps on happening after 14seconds from the boot;

- the device re-boots continuously after the hw reset because VIN is present;

Conclusion:

It seems that it not possible to disable the hw reset in the condition described above.

Could I kindly have a feedback from you please ?

Thanks in advance !

Riccardo Gaiati

9 months ago

0 Juan Ospina 9 months ago

TI__Genius 13785 points

Hi Riccardo,

Can you please share your register settings?

You should be able to prevent a HW Reset condition while an /MR press is occurring by writing MR_LPRESS_ACTION to 0b01. Can you confirm that this value can be read back from the register after it's been written?

Best Regards,

Juan Ospina

0 Riccardo Gaiati 8 months ago in reply to Juan Ospina

Prodigy 70 points

Hi Juan,

thanks for your reply.

I can confirm that the value it is written into the register.

I will enable the interrupt sent 1 second before the hw reset just to be sure that the reset we experience is due to the pmu.

thanks again !

0 Juan Ospina 8 months ago in reply to Riccardo Gaiati

TI__Genius 13785 points

Thanks Riccardo, I'll await your results.

Best Regards.

0 Riccardo Gaiati 8 months ago in reply to Juan Ospina

Prodigy 70 points

Confimed that the reset is not due to the button pressed.

0 Juan Ospina 8 months ago in reply to Riccardo Gaiati

TI__Genius 13785 points

Hi Riccardo,

Was your issue resolved? How did you confirm that it is not due to the button press?

Best Regards,

Juan Ospina

0 Riccardo Gaiati 8 months ago in reply to Juan Ospina

Prodigy 70 points

Hi Juan,

I think it is not due to the press of the button for the following reasons:

- the HW reset behavior associated to the MR pin is disable as described in the picture above;

- the same register is read back and the proper setting is there (no actions);

- the reset seems due to a drop in the external voltage VIN (battery voltage is basically 0);

We are investigating to understand why there is a drop in the external voltage VIN. So, it is not solved yet.

Kind regards

Riccardo

+1 Juan Ospina 8 months ago in reply to Riccardo Gaiati

TI__Genius 13785 points

Hi Riccardo,

I see, it sounds like this may be unrelated to the BQ device behavior then. If you have further questions regarding the BQ then please feel free to reply or start a new thread.

Best Regards,

Juan Ospina

Power management

Power management forum

BQ25155: BQ25155 reset button behavior