BQ77908A Li-Ion balancing and protection

Discussion in 'The Projects Forum' started by Dollarday, Oct 22, 2012.

  1. Dollarday

    Thread Starter Active Member

    Jan 25, 2012
    Hi Everyone :cool:,

    I would like to use the bq77908A to create my own protection and balancing circuit for a battery pack.

    The bq77908A has internal 50mA cell balancing capability, cell undervoltage, cell overvoltage, pack charge and discharge overcurrent protection.

    NOW, my question is... What is the maximum discharge current of a battery pack connected to a bq77908A IC.

    My gut tells me that the discharge current of the battery pack is independant of the bq77908A... as long as the detection voltage of the maximum discharge current is not exceeded. Your sense resistor needs to be small enough or the EEPROM needs to be correctly programmed. (See table 1 in the datasheet)

    In other words, if the selection of the sense resistor and N-channel FET's are correct, then the battery pack can have ANY discharge current. (See figure 2 in the datasheet)

    Am I correct in the assumption that a battery pack connected to a bq77908A can have any discharge current? Is there somewhere this is verified on the datasheet?