BQ25898D: About Charging Current Setting

user777540

Part Number: BQ25898D

hello,

Please tell me about Table 6.Charging Current Setting in the datasheet.

When VBAT is 2V to 3V, IPRECHG=0mA(DEFAULT).
If VBAT is 2V-3V when running in Default Mode, does it not charge permanently?
Will the 4-hour Safety Timer expire and end the charge?

best regards

over 5 years ago

0 Ning T over 5 years ago

TI__Guru 57651 points

Hi,

Iprecharge is set to 0mA when Ichg REG04[5:0] = 000000. Otherwise, the default Iprecharge is 128mA.

Thanks,

Ning.

0 Ning T over 5 years ago in reply to Ning T

TI__Guru 57651 points

Hi,

The safety timer is 4 hours when the battery is below VBATLOWV threshold (i.e. precharge).

Thanks,

Ning.

0 user777540 over 5 years ago in reply to Ning T

Expert 1020 points

hello,

Is the Precharge Current Limit register setting as follows?

If VBAT is 2V-3V when running in Default Mode, does it not charge permanently?
Will the 4-hour Safety Timer expire and end the charge?

Iprecharge is set to 0mA when Ichg REG05[7:4] = 000000. Otherwise, the default Iprecharge is 0mA.

best regards

0 Ning T over 5 years ago in reply to user777540

TI__Guru 57651 points

Hi,

The default Ichg REG04[5:0]=2048mA, so the default Iprecharge=128mA. The battery should be charged up normally during precharging. If the battery voltage is still in precharge status after 4 hours, charging will stop.

Thanks,

Ning.

0 user777540 over 5 years ago in reply to Ning T

Expert 1020 points

hello,

About the Pre-charge Current in the datasheet
The bq25898D (Pre-charge Current) in Table 5 is listed as 128mA.
On the other hand, 2 V - 3 V (IPRECHG) in Table 6 is described as 0 mA (precharge disabled).
Please tell me why there is a difference between Table 5 and Table 6.

best regards

0 Ning T over 5 years ago in reply to user777540

TI__Guru 57651 points

Hi,

The default Iprecharge is 128mA because the default Ichg REG04[5:0]=2048mA. Iprecharge is set to 0mA when Ichg REG04[5:0] is set to 000000.

Thanks,

Ning.

0 user777540 over 5 years ago in reply to Ning T

Expert 1020 points

hello,

About REG DEFAULT SETTING column of 2 V-3 V (IPRECHG) in Table 6
Is the description of 0 mA (precharge disabled) incorrect?

best regards

0 Ning T over 5 years ago in reply to user777540

TI__Guru 57651 points

Hi,

The information is not accurate. It will be updated in the next revision of d/s.

Thanks,

Ning.

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BQ25898D: About Charging Current Setting