BQ4050: BQ4050 Full Charge Capacity restriction

Part Number: BQ4050


The Full Charge Capacity (FCC) of the BQ4050 fuel gauge is updated based on charge-discharge cycles. However, when the actual capacity decreases and the Full Charge Capacity becomes less than the Design Capacity minus 256 mAh, the Full Charge Capacity ceases to update and remains at the value of (Design Capacity - 256 mAh). What is the root cause?