BQ76922: CFET timing of CFETOFF versus I2C Command

Hello Keith,

Apologies for the delay and thanks for your patience. I think this previous thread, CFET turn ON Delay Time, may help answer your question. 

Best Regards,
Alexis

Hello Keith,

I realized you were asking for turn-off, and I think this previous thread is more helpful instead. The FET turnoff action can be delayed up to 250ms in NORMAL mode, however, by changing the setting to 0x98 or 0xE4, it should be a faster turn-off. 

Best Regards,
Alexis

Hello Keith,

Blue = CHG pin, Purple = SDA, Green = SCL,

I was able to grab a waveform to show the turn-off time with the ALL_FETS_OFF subcommand and the configuration below. From when the command was sent, to when the CHG pin turned OFF, it took around ~1.6ms.

CHG FET Protections A = 0x98

Best Regards,
Alexis

Hello Domenick,

I believe both should be able to be configured as an open drain output/Active Low. 

Domenick DAmico said:

Also, another question is how quickly the I/O can be driven high and low, would we have the 250ms delay? Or could it be consistently quicker?

This previous post (+) BQ76952: Turn-off and turn-on MOS speed of DFEOFF and CFEOFF of bq76952 - Power management forum - Power management - TI E2E support forums should help answer this question.

Best Regards,
Alexis