The LM5008A must be operated so the junction temperature does not exceed 125°C during normal operation. An internal Thermal Shutdown circuit is provided to shutdown the LM5008A in the event of a higher than normal junction temperature. When activated, typically at 165°C, the controller is forced into a low-power reset state by disabling the buck switch. This feature prevents catastrophic failures from accidental device overheating. When the junction temperature decreases below 140°C (typical hysteresis = 25°C), normal operation continues.