bq24616 / Battery Detection waveform

S.Satoshi

Hi,

Please let me ask about battery detection waveform. I checked the battery detection operation and then the detection is operated at 500msec cycle but such duration is not included in flow chart. Is there 500msec wait time after disable 125mA charge?

Best Regards,

Sonoki

over 9 years ago

0 Steven Bangdiwala over 9 years ago

TI__Expert 8690 points

Hi Sonoki,

This is the same waveform I see on the bench. It is a minimum time to re-detect battery, this way the waveform is not always charging and discharging at a high pace and consume a lot of power.

Regards,
Steven

0 S.Satoshi over 9 years ago in reply to Steven Bangdiwala

Guru 21685 points

Hi Steven,

I also think this is correct operation, but I think that this operation does not correspond with flow chart. I'd like to know this is estimated behavior.

Best Regards,
Sonoki

0 Steven Bangdiwala over 9 years ago in reply to S.Satoshi

TI__Expert 8690 points

Sonoki,

Yes this is expected behavior.

Regards,
Steven

0 S.Satoshi over 9 years ago in reply to Steven Bangdiwala

Guru 21685 points

Hi Steven,

Please let me ask about battery detection waveform again.

I understand that there is no charge and discharge current at the duration A in page 1 of attached. Is my understanding correct?
I confirmed that the reversed inductor current at duration A, but the LS FET was not turned on. I don't understand why reversed inductor current is occurred at LS FET turned off. Can you explain this operation?

Bq24616 Battery Detection waveform_20160607.pdf

Best Regards,

Sonoki

0 Steven Bangdiwala over 9 years ago in reply to S.Satoshi

TI__Expert 8690 points

Hi Sonoki,

The charge/discharge goes quickly because there is nothing that will hold the voltage at the same level, for example, a battery inserted.

The device is running in non-synchronous mode. You can look into the description at page 19 of the datasheet.

The LSFET only turns on to recharge the BTST cap. As for negative inductor current, its basically going back into the input cap through the HSFET diode.

Regards,
Steven

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bq24616 / Battery Detection waveform