Hi TI-team
My customer have a question.
It states that the thermal shutdown threshold is 175°C.
The thermal shutdown does not operate within the guaranteed operation range (-40 to 150°C) even if the temperature sensor variation is included.
Is this perception correct ?
In other words, does thermal shutdown take place at 150°C?
Best Regards,
Koji Hayashi
Hello Hayashi-san,
The thermal shutdown does actually take place at 175°C. The -40°C to 150°C range is the the where the device is to guaranteed to operate correctly with datasheet parameters under steady state DC conditions. Essentially you should only design your application so that it never goes above 150°C in the nominal state.
If your maximum DC load current is going to be 2A with a 85°C ambient temperature, for example, you would calculate the junction temperature by:
(note we are using 166mΩ as the worst case RON). This means you would never get close to the actual thermal shutdown and the device would behave as expected. More details can be found in the following application note:
https://www.ti.com/lit/slvae30
For the TPS1H100-Q1 you can also calculate how the device behaves thermally by using the thermal PSPICE model. More details on how to do this can be found in the following application note:
https://www.ti.com/lit/pdf/slvaez0
The 175°C thermal shutdown number is a fail safe mechanism so that the device will never get damaged physically. You should ideally never hit this number unless you have a short-to-ground or other fault case.
