Part Number: BQ40Z50-R2
I am using a bq40z50 fuel gauge on 4 series Lipo 5AH cells. My charger is the bq24600. I am using the precharge profile of bq24600 and have no precharge FET in the bq40z50 implementation. Initial operation both CHG and DSG FETs are on.The charger brings the cells to 4.2 V and the CHG FET turns off.Cell balancing does its thing and all cells are soon within 3mV P-P. When a load is applied to VSYS, both CHG and DSG FETs are on. The discharge proceeds till cell voltages are scattered around 3000 mV. The CHG FET turns off and inhibits recharging. the DSG FET remains on. Recharging is impossible without a RESET command.
bq studio does not lose communication. The only safety status bit set is OC. i am missing something in the configuration. Suggestions would be appreciated. Attached is a image of the registers.
I have not been able to complete a learning cycle until i can both charge and discharge the pack.
thanks,
Jerry