Infineon’s automotive linear regulators are designed to withstand junction temperatures up to 150°C. Package and heat sink selections need to ensure that the maximum junction temperature is not exceeded in any operating condition.
To prevent IC damage in fault conditions (e.g. output continuously short-circuited), a thermal shutdown has been integrated. The circuitry switches off the power stage for a junction temperature higher than 151°C, typically 175°C, unless otherwise specified in the datasheet. The device re-starts automatically after cooling down with a typical hysteresis of 15K (e.g. with a thermal shut-down at 175°C, re-start occurs at 160°C).
Temperature above 150°C is outside the maximum ratings of the voltage regulators and reduces the IC lifetime significantly.
Thermal shutdown and hysteresis