JAJSEC4E September 2012 – January 2018 BQ24157
PRODUCTION DATA.
For applications with removable battery packs, the IC provides a battery absent detection scheme to reliably detect insertion or removal of battery packs.
During the normal charging process with host control, once the voltage at the CSOUT pin is above the battery recharge threshold, VOREG- VRCH, and the termination charge current is detected, the IC turns off the PWM charge and enables a discharge current, IDETECT, for a period of tDETECT, (262 ms typical) then checks the battery voltage. If the battery voltage is still above the recharge threshold after tDETECT, the battery is present. On the other hand, if the battery voltage is below the battery recharge threshold, the battery is absent. Under this condition, the charge parameters (such as input current limit) are reset to the default values and charge resumes after a delay of TINT. This function ensures that the charge parameters are reset whenever the battery is replaced.