ZHCSJR3B February 2019 – November 2019 BQ25887
PRODUCTION DATA.
The device monitors internal junction temperature, TJ, to avoid overheating and limits the IC surface temperature in boost mode. When the internal junction temperature exceeds the preset thermal regulation limit (TREG bits), the device reduces charge current. A wide thermal regulation range from 60°C to 120°C allows optimization for the system thermal performance.
During thermal regulation, the actual charging current is usually below the programmed value in ICHG registers. Therefore, termination is disabled, the safety timer runs at half the clock rate, the status register TREG_STAT bit goes high, and an INT is asserted to the host.
Additionally, the device has thermal shutdown to turn off the converter when IC surface temperature exceeds TSHUT. The fault register bits TSHUT_STAT and TSHUT_FLAG are set and an INT pulse is asserted to the host. The converter turns back on when IC temperature is below TSHUT_HYS.