3 Performing a watchdog reset

In some scenarios, when the system processor or host is nonresponsive, a forced hardware reset or a power cycle might be necessary; you can accomplish this with a watchdog reset. For instance, on TI’s BQ25180 charger device, a hardware reset is possible when meeting conditions such as:

• No I2C communication for 15 s or more after plugging in the adapter.
• The user pressed the reset button for an extended period of time.
• A duration >40 s from the last I2C communication.

During a hardware reset sequence, the charger IC disconnects the system from the battery and adapter (if present), waits for a configurable duration, and then turns the system back on, enabling system startup and initialization. Because the battery is physically connected to the system, an external load switch might be necessary in a non-power path charger device to perform a hardware reset.