Other Parts Discussed in Thread: BQSTUDIO
I have interfaced a BQ76952 with a host MCU through SPI. The BQ IC does not have any temperature sensors (NTC) connected to its pins. The MCU is measuring all required temperature. MCU is also responsible for load detection, charger detection and current sensing. BQ only measures cell voltages and is required for cell balancing.
Problem: When I send Activate Cell Balancing command along with a given cell number, no balancing takes place even though on reading back the registers, I get the cell number I had written.
Ques 1.) Do I need to disable any balancing parameters (temperature, cell voltages, etc) to force BQ to start balancing? I do not require auto-balancing. Also, with various temperature input pins, how does BQ calculate cell temperature?
I have currently 16 cells connected to BQ. I am able to read all cell voltages and the communication seems to work fine.
Ques 2.) It is mentioned that pin for cell 16 should always be connected to a real cell. If I have, say 14 cells, can I connect them till 14 pin, and short pin 15 and 16 to pin 14?
If no, then, if I connect 13 cells till pin 13 and 14th cell to pin 15 and 16 , where should I connect the 14 pin: to pin 15 or pin 13?
I have a production scheduled in a month. The requirement that pin 16 and 15 always needs to be connected poses some assembly issues, as for different series requirement, different cells go into pin 16 and 15. Is there a work around?