BQ24780S: BQ24780S REGN on in battery-only performance mode

Hello Zhang,

Zhang Excellent said:

As we know, BQ24780S REGN is only on when ACDET is above 0.6V,according to datasheet.

But why is REGN also on when charger is in battery-only performance mode where ACDET is below 0.6V?

This is only true when adapter is present.

Zhang Excellent said:

2, When in battery-only performance mode, REGN LDO is enabled (except for IDCHG buffer) for accurate reference, does reference herein mean VREF (reference voltage) for all the comparators shown in Functional Block Diagram in datasheet?? 

Can you clarify this question?

Zhang Excellent said:

3, Why does BA24780S need battery-only performance mode compared with battery-only low power mode?

IC in low power mode with battery only. IC is in the lowest quiescent current when this bit is PROCHOT, discharge current monitor buffer, power monitor buffer, battery only boost mode and independent comparator are disabled. So, if you need these features when operating with just the battery, then you need to be in performance mode, but if you do not, and you want longer battery life, you can enter low power mode.

Zhang Excellent said:

4, Does BQ24780S also have low power mode and performance mode when adapter is on?

No, Low power mode is used to conserve battery life in battery only mode.

Best Regards,

Christian.

Hello Zhang,

The last sentence. When the Adapter is removed, and low power mode is disabled, REGN LDO is enabled when any of the below functions is enabled.

Best Regards,

christian.

Hello Zhang,

Zhang Excellent said:

Where can I find the document including the text shown in your picture?

This is in the spec sheet. I will work on getting it added to datasheet.

Zhang Excellent said:

This means the REGN LDO will NOT be on if only IDCHG buffer is enabled by SMBUS,right? and if yes, why?

Yes, This is correct.

Best Regards,

Christian.