View r3111x-series datasheet:

R3111x SERIES LOW VOLTAGE DETECTOR NO.EA-056-070829 OUTLINE The R3111x series are CMOS-based voltage detector ICs with high detector threshold accuracy and ultra-low supply current, which can be operated at an extremely low voltage and is used for system reset as an example. Each of these ICs consists of a voltage reference unit, a comparator, resistors for detector threshold setting, an output driver and a hysteresis circuit. The detector threshold is fixed with high accuracy internally and does not require any adjustment. Three output types, Nch open drain “L” type, Nch open drain “H” type and CMOS type are available. The R3111x Series are operable at a lower voltage than that for the Rx5VL series, and can be driven by a single battery. Six types of pac