Patent ID: 6995587

Claim:
An under-voltage detection circuit for providing under-voltage detection in a circuit having a supply voltage VDD, a ground, and an input voltage Vin, the under-voltage detection circuit comprising: a first current mirror circuit operatively coupled to the supply voltage VDD; a bandgap reference current circuit operatively coupled to the first current mirror and ground, the bandgap reference circuit adapted for deriving a bandgap current proportional to absolute temperature, IPTAT; an input node for accepting an input voltage Vin; an input resistor coupled to the input node for inducing an input current lin; a comparator circuit coupled to the bandgap reference circuit and the input node for comparing the IPTAT and the input current lin; an output node coupled to the comparator for providing either a high output or a or low output indication of whether an under-current condition exists, wherein the bandgap reference current circuit further comprises: a first bipolar transistor having a collector operably coupled to the first current mirror and an emitter coupled to ground; and a first resistor operably coupled to a base of the first bipolar transistor.