BQ28Z620: PTO suspend condition

Kailun Liu

Part Number: BQ28Z620

Hi team,

Could you help to check below PTO suspend condition: current<threshold.

From my understanding, the IC start pre-charge when the Vbat is lower than 3.0V. When the Vbat>3.0V, the IC will exit pre-charge and charging current will increase.

If the suspend condition is current <threshold, which means the PTO timer will not stop counting when pre-charge is exited.

over 1 year ago

0 Jonny over 1 year ago

TI__Mastermind 24931 points

Hello Kailun,

I'm not sure that I fully understand what you are asking here, can you please elaborate?

Regards,

Jonny.

0 Kailun Liu over 1 year ago in reply to Jonny

TI__Expert 3103 points

Hi Jonny,

When the Battery voltage is below 3.0V, it will start pre-charge at first. With the voltage recovered, charger/gauge will exist pre-charge and start normal charge, right? The charging current will increase and larger than it in pre-charge period.

As we can see, the PTO timer stopped condition is that current()<PTO: suspend Threshold. I think it should be ">", otherwise the timer will not stop when gauge exit from pre-charge and start normal charge.

0 Jonny over 1 year ago in reply to Kailun Liu

TI__Mastermind 24931 points

Hello Kailun,

The timer also gets stopped when the PTO Timer > PTO:Delay.

Regards,

Jonny.

0 Jonny over 1 year ago in reply to Jonny

TI__Mastermind 24931 points

Hello Kailun,

I have just consulted with the team on this and I believe your understanding here is correct, this might be a mistake in the device TRM.

Regards,

Jonny.

0 Kailun Liu over 1 year ago in reply to Jonny

TI__Expert 3103 points

Thanks Jonny,

On the other hand, I think here is also another condition that if we stop pre-charge before it starts normal charge, the current< threshold, at this time the timer should stop.

0 Jonny over 1 year ago in reply to Kailun Liu

TI__Mastermind 24931 points

Hello Kailun,

Here with the PreCharge timeout protection, it looks like the main focus here should be on the trip point, as this is where the action takes place.

Regards,

Jonny.

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BQ28Z620: PTO suspend condition