Low-dropout linear regulators double as voltage-supervisor circuits

摘要

Many low-dropout voltage regulators include an enable-input pin that can also serve as an inexpensive alternative to a voltage-supervisor IC. Although the enable pin normally serves as a means of shutting down the regulator's output to save power, a few discrete components ensure that the regulator's output will turn on and off at appropriate input voltages. Thus, you can use the circuit as a voltage supervisor or as a controlled-char-acteristic linear-voltage regulator.