ZHCSJ56C February 2018 – September 2019 BQ25882
PRODUCTION DATA.
The device is a host controlled charger, but it can operate in default mode without host management. In default mode, the device can be used as an autonomous charger with no host or while host is in sleep mode. When the charger is in default mode, WD_STAT bit is HIGH. When the charger is in host mode, WD_STAT bit is LOW.
After power-on-reset, the device starts in default mode with watchdog timer expired, or default mode. All the registers are in the default settings.
In default mode, the device keeps charging the battery with default 10-hour fast charging safety timer. At the end of the 10-hour, the charging is stopped and the boost converter continues to operate to supply system load.
A write to any I2C register transitions the charger from default mode to host mode, and initiates the watchdog timer. All the device parameters can be programmed by the host. To keep the device in host mode, the host has to reset the watchdog timer by writing 1 to WD_RST bit before the watchdog timer expires (WD_STAT bit is set), or disable watchdog timer by setting WATCHDOG bits = 00.
When the watchdog timer (WD_STAT bit = 1) is expired, the device returns to default mode and all registers are reset to default values except as detailed in the Register Maps section.