SBVS233B January 2016 – June 2021 TPS7A84
The TPS7A84 contains a thermal shutdown protection circuit to disable the device when thermal junction temperature (TJ) of the main pass-FET exceeds 160°C (typical). Thermal shutdown hysteresis assures that the LDO resets again (turns on) when the temperature falls to 140°C (typical). The thermal time-constant of the semiconductor die is fairly short, and thus the device cycles on and off when thermal shutdown is reached until the power dissipation is reduced.
For reliable operation, limit the junction temperature to a maximum of 125°C. Operation above 125°C can cause the device to exceed its operational specifications. Although the internal protection circuitry of the TPS7A84 is designed to protect against thermal overload conditions, this circuitry is not intended to replace proper heat sinking. Continuously running the TPS7A84 into thermal shutdown or above a junction temperature of 125°C reduces long-term reliability.