Texas Instruments has introduced a reset chip for voltage rails between 1.5V and 10V, that can work on 24V rails with additional resistors (see below). Called the TPS3840 family, supply current is typically 300nA, and is 700nA max over temperature. Threshold voltage is fixed, and versions are available from 1.6 to 4.9V in 0.1V steps – ...

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