The device has built-in safety timers to prevent an extended charging cycle due to abnormal battery conditions. When the safety timer expires, the charge cycle ends.

During thermal regulation, the safety timer counts at half the clock rate as the actual charge current is likely to be below the ISET setting. For example, if the charger is in thermal regulation throughout the whole charging cycle and the safety timer is 10 hours, then the timer will expire in 20 hours.

During faults which disable charging, such as VIN OVP, BAT OVP, TSHUT, or TS faults, the timer is suspended. If the charging cycle is stopped and started again, the timer is reset (toggle of the TS pin restarts the timer).

The safety timer restarts counting when the charging cycle stops and restarts. This can occur as a result of the TS pin being toggled, the battery falling below the recharge threshold, or the input supply being toggled.