BQ24092: Charge current variation

Sreekanth Anegunda

Part Number: BQ24092

Hi,

We are using BQ24092 for charging Li-ion battery. The input voltage is 5V, current set to ~870mA and using a NTC for temperature sense.

When the battery voltage is less than 3V the battery is charged with precharge current and when the battery voltage reaches above ~2.8V the current drawn from the supply was ~880mA. But when the battery was getting charged the input current started dropping from ~880mA (~2.8V) to 460mA (4.076V).

Is this normal behavior of charger?

As per the Datasheet figure 14 the constant current phase should continue till the battery voltage reaches the voltage regulation. But in our case the current started decreasing when the battery voltage started increasing.

Thanks,

Sreekanth

over 5 years ago

0 Bill Johns over 5 years ago

TI__Guru 67876 points

Hi Sheekanth

"But in our case the current started decreasing when the battery voltage started increasing." -- Bill J - This suggests that the input to output voltage difference is too low. Check voltage difference across the device when output current drops.

0 Sreekanth Anegunda over 5 years ago in reply to Bill Johns

Intellectual 975 points

Hi Bill,

The voltage on Input pin was less, after adjusting the voltage to 5V the current is constant. Thanks for your support.

Thanks,
Sreekanth

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BQ24092: Charge current variation