Thermal shutdown prevents the device from extreme junction temperatures by turning off the internal switches when the IC junction temperature exceeds 168°C (typical). Thermal shutdown does not trigger below 158°C. After thermal shutdown occurs, hysteresis prevents the device from switching until the junction temperature drops to approximately 158°C. When the junction temperature falls below 158°C (typical), the converter attempts to soft start.

While the converter is shut down due to high junction temperature, power continues to be provided to VCC. To prevent overheating due to a short circuit applied to VCC, the LDO that provides power for VCC has reduced current limit while the converter is disabled due to high junction temperature. The VCC current limit is reduced to a few milliamperes during thermal shutdown.