BQ28Z620EVM-071: Remaining Capacity is Always Zero

Gordon McKenzie

Part Number: BQ28Z620EVM-071
Other Parts Discussed in Thread: GPCCHEM

Tool/software:

Hello,

I'm trying to use the BQ28Z620EVM but I find that the full charge capacity and remaining capacity are always zero. I currently have the charge and discharge FETs shorted out so that current flows between PACK connections and battery connector J2.

The battery capacity is correctly set in the design memory as 3350mAh. The current is reported correctly (both charge and discharge) but it is not setting remainging capacity so is useless for monitoring state of battery charge.

What do I need to do to get it to do this properly?

5 months ago

0 Alan Frias 5 months ago

TI__Mastermind 26135 points

Hello Gordon,

Your question has been assigned and we are currently working on the solution.

Thank you,
Alan

0 Alan Frias 5 months ago

TI__Mastermind 26135 points

Hello Gordon,

I would re follow the EVM user guide, there is a lot that could've gone wrong within your process of setting up the guide. The beginning steps to start is parameter selection in the data memory tab >> calibration within calibration tab >> parameter selection in the data memory tab >> GPCCHEM calculator report >> Program in ChemID >> Cell learning cycle >> exporting golden image file .srec.

EVM:
https://www.ti.com/lit/ug/sluucq5/sluucq5.pdf?ts=1743097420185&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FBQ28Z620EVM-071

Critical Parameters:
Design Capacity, Design Voltage, Charge Term Taper Current, Discharge (Dsg) Current Threshold, Charge (Chg) Current Threshold, Quit Current and Term Voltage

GPCCHEM:
https://www.ti.com/tool/GPCCHEM

Learning cycle:
https://www.ti.com/lit/an/slua903/slua903.pdf?ts=1741893409900&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fen-us%252Fdocs%252Funiversalsearch.tsp%253FlangPref%253Den-US%2526nr%253D85%2526searchTerm%253DHow+to+achieve+a+success+learning+cycle

Thank you,
Alan

Power management

Power management forum

BQ28Z620EVM-071: Remaining Capacity is Always Zero