7.3.10 Thermal Protection

The junction temperature of the LMR24220 should not exceed the maximum limit. Thermal protection is implemented by an internal thermal shutdown circuit, which activates (typically) at 165°C to make the controller enter a low power reset state by disabling the main MOSFET, disabling the on-timer, and grounding the SS pin. Thermal protection helps prevent catastrophic failures from accidental device overheating. When the junction temperature falls back below 145°C (typical hysteresis = 20°C), the SS pin is released, and normal operation resumes.