Hey Battery Fuel Gauge team,
I have a customer evaluating the BQ40Z80 for a new design and we are running into a problem which I'm hoping you can help to provide some clarity on. Please see a summary below of the issue and let us know if you need any additional info to provide guidance!
Summary of issue: We are seeing the BQ40Z80 reset after a series of SMBus communications. The BQ chip successfully communicates for a few seconds before resetting. It seems to be fixed when we reduce the rate at which we communicate with the BQ.
It seems to happen after a read that doesn't return real data and instead returns 20 bytes of 0xFF. In the logic data attached below (acquired by using a Salae), the failure happens after an attempted read at manufacturer access code 0x0071 (DAStatus1). You can see that before the failure, we successfully read the DAStatus1 register previously multiple times. After a few seconds in, the chip resets.
The voltage line that goes up to about 12V is the battery output voltage.
Any ideas of what might be causing this?
Best regards,
Matt Calvo
