SLUSFN0A April 2025 – December 2025 BQ25630
PRODUCTION DATA
The device is a host controlled charger, but the device 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 becomes HIGH, WD_FLAG is set to 1b, and an INT is asserted low to alert the host (unless masked by WD_MASK). The WD_FLAG bit reads as 1b upon the first read and then 0b upon subsequent reads. 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. All the registers are in the default settings.
In default mode, the device keeps charging the battery with default 1-hour trickle charging safety timer, 2-hour pre-charging safety timer and the 12-hour fast charging safety timer. If any of these timers expire, charging is stopped and the buck converter continues to operate to supply the 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 1b to WD_RST bit before the watchdog timer expires (WD_STAT bit is set), or disable watchdog timer by setting WATCHDOG bits = 00b.
When the watchdog expires, the device returns to default mode. The ICHG value is divided in half when the watchdog timer expires, and a number of other fields are reset to the POR default values as shown in the notes column of the register tables in Section 8.6.2. The watchdog timer is reset on any write if the watchdog timer has expired. When watchdog timer expires, WD_STAT and WD_FLAG are set to 1b, and an INT is asserted low to alert the host (unless masked by WD_MASK). If WD_MODE bit is set to 1b and the watchdog timer expires, a system reset occurs.
