Figure 8-4 shows a self-test scheme where a manual self-test function can be implemented. SENSE4 has an overvoltage (OV) threshold that is set at 5.5 V and the undervoltage (UV) threshold set at 2 V. SENSE4 can be connected via a 100-kΩ resistor to VDD. The self-test setup gives the added benefit of a built-in overvoltage detector for the rail powering the TPS37044F-Q1. From a functional safety perspective, a voltage supervisor cannot be considered reliable if the supervisor is operating outside its recommended operated limits.

To trigger a manual self-test, pull UV_Trig high to cause SENSE4 to be logic low, therefore triggering an undervoltage (UV) fault. The UV fault appears at RESET2 as an asserted low signal. By tying both reset outputs to an NMI or interrupt input of the processor, this self-test option scheme serves as a purpose to ensure that RESET2, of the TPS37044F-Q1 is operating properly. For more information on functional safety, see the Functional Safety Manual.