BQ76940: balancing with transistor

Hi Minqi,

Yes, the BQ76940 could support BJT transistors for balancing instead of FETs, but balance current will typically be lower than with a FET.  Due to the architecture of the BQ76940 the input resistance must be large to keep the part powered during short circuit events as described in https://www.ti.com/lit/pdf/slua749 , so the base current will be low and even with high gain transistors the balance current may not match what is available from a FET using a single transistor.  You could use the BJT to control the base of a second BJT for higher gain, or a MOSFET to get the full cell voltage for Vgs and thus lower RDSON and higher balance current.  This is more components, I don't know of an available example.