It monitors power supplie in computers and digital systems as well as appliances, and will generate a reset signal whenever a supply rail falls below a defined threshold. This function is required by computers and communication equipment, and also portable, battery-powered devices, says the company. The low quiescent current also makes it a suitable choice for when appliances, like TVs, are operating in standby mode.

Detection voltage level range is 1.2 to 5.0V in 0.1V steps, to provide a threshold accuracy of ±1.5%, while consuming just 1μA. No external components are required. Whenever the monitored V_CC power supply rail drops below the chosen threshold, the detector asserts a reset signal within 20μs that is held until the supply rail recovers to a level above the threshold. The device’s reset pin provides an open-drain, active-low output with device ordering options that allow for delay times of 0, 55, 220, or 450ms.

Available in three-pin SOT23, SOT323, and SC59 packages and a five-pin SOT25 package, the APX803L can be used as a drop-in replacement and for original designs.