ZHCS229C September 2011 – January 2020 BQ24725A
PRODUCTION DATA.
A battery LEARN cycle can be activated via SMBus command (ChargeOption() bit[6]=1 enable LEARN cycle, bit[6]=0 disable LEARN cycle). When LEARN is enabled with ACFET/RBFET connected, the system power selector logic is over-driven to switch to battery by turning off ACFET/RBFET and turning on BATFET. LEARN function allows the battery to discharge in order to calibrate the battery gas gauge over a complete discharge/charge cycle. The controller automatically exits LEARN cycle when the battery voltage is below battery depletion threshold, and the system switches back to adapter input by turning off BATFET and turning on ACFET/RBFET. After LEARN cycle, the LEARN bit is automatically reset to 0. The battery depletion threshold can be set to 59.19%, 62.65%, 66.55%, and 70.97% of voltage regulation level via SMBus command (ChargeOption() bit[12:11]).