BQ24192I: Powering SYS from BAT only

Nir Dvash1

Part Number: BQ24192I

Hey all,

Using this device, I know I can control the charging of the battery using the CE pin or REG01(5:4) bits but is there also a way

to force the device to power SYS only from the battery, even when a valid charger is powering the VBUS input?

Also, how 'healthy' is it for a lit-ion battery if I connect a load to SYS which is changing from zero to about 2 amps in cycles of a few seconds all while VBUS is connected and trying to charge the battery

at the same time (1A charge current), assuming VBUS can handle this load?

Thank you!

Nir

over 4 years ago

0 Ning T over 4 years ago

TI__Guru 50791 points

Nir,

1. Yes. The host may set EN_HIZ REG00[7]=1 via I2C, the device will enter HIZ mode with REGN LDO and the bias circuits off. And the VBUS current during HIZ state will be less than 30 µA. The system is supplied by the battery.

2. If VBUS has enough power to handle SYS load and charging current, the charger will continue operating normally.

Thanks,

Ning.

0 Nir Dvash1 over 4 years ago in reply to Ning T

Intellectual 470 points

Hey Ning,

Thank you. You also helped me on my last question a few months ago.

As for your answer 2 - I was referring more to the battery itself - Do you think it is OK for a lit-ion battery to be charged in small cycles and discharge in between like I have described in my question?

Nir.

0 Ning T over 4 years ago in reply to Nir Dvash1

TI__Guru 50791 points

Nir,

Please check with the battery manufacturer.

Thanks,

Ning.

0 Nir Dvash1 over 4 years ago in reply to Ning T

Intellectual 470 points

Thank you Ning.

One last question: If the battery is supervised by the BQ24192L IC, does this mean that I can connect a battery without a PCM circuit (like AX1032)?

Nir.

0 Ning T over 4 years ago in reply to Nir Dvash1

TI__Guru 50791 points

Nir,

I'm unable to find AX1032 information online. If you are referring to battery protection or battery fuel gauge, they are optional, but nice-to-have. It is ok to connect the battery to the charger directly as shown on Typical Applications on the d/s.

Thanks,

Ning.

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BQ24192I: Powering SYS from BAT only