• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 62 subscribers
  • Views 157 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ25700A: BQ25700A battery presence detection

Hollis Liu
Intellectual 2535 points
Part Number: BQ25700A

HI team,

Can BQ25700A detect whether the battery is present by itself? Do you have any idea to do battery presence detection by bq25700A? Thanks. 

  • 0
    TI__Mastermind 25800 points

    Hey Hollis,

    The BQ25700A cannot detect the absence of a battery by itself.

    You can attempt a few things:

    1) If you have external circuitry that can detect the presence of the battery, you may use that to pull the CELL_BATPRESZ pin LOW. This will inform the charger that the battery has been removed.

    2) Alternatively, I have seen other customers use the battery's integrated thermistor (if the battery has one) in conjunction with an N-Ch. MOSFET on the CELL_BATPRESZ pin, which would turn on the MOSFET if the battery is removed. This in effect would have the same response as (1).

    3) When the IBAT current is very low and the VBAT voltage is at the regulation voltage (use the charger's integrated ADC), you can disable charge and use the EN_SHIP_DCHG bit to apply a small pull-down current on the SRN node, and recheck the ADC VBAT value. If dropped significantly, it is likely the battery is removed. This implementation is more complex firmware-wise.

    Regards,

    Joel H