Thermal shutdown is a function that prevents the IC from malfunctioning, suffering characteristic degradation, or being damaged when the IC junction temperature becomes excessively hot.
In the case of general voltage regulators and DC/DC, when the thermal shutdown function activates, the current supply to the output side is stopped, and output turns off.
When the current supply to the output side stops, self-heating stops, which decreases the junction temperature.
For ICs with a built-in self-reset type thermal shutdown function, when the junction temperature decreases to the thermal shutdown reset temperature, the IC restarts.
When the excessive load continues after restarting, the thermal shutdown activates again, and it will behave by repeatedly detection and reset.
DC/DC converter (XC6702): Thermal shutdown detection ⇔ Reset state
(Condition: Vin=11.8V, Vout=1.8V)
There are also products with a similar function where the charger IC monitors the battery temperature and performs optimum charging control based on the battery temperature state.