Patent ID: 7728633

Claim:
A window comparator of an A.C. input voltage, consisting of: between two terminals of application of a voltage representative of the voltage to be measured, two first transistors of a first type, each first transistor being assembled as a current mirror on a second transistor having a first conduction terminal connected to one of said application terminals, the two second transistors having a second common conduction terminal, the two first transistors performing full wave rectification of said voltage representative of the voltage to be measured; and two third transistors of a second type assembled as a current mirror between said common conduction terminal of the second transistors and a current source, a D.C. voltage being applied on a first terminal of said current source and an output signal being provided by a second terminal of the current source, wherein the two third transistors are configured to compare a measured current provided by the two second transistors to a reference current provided by the current source and to provide the output signal indicative of a result of the comparison, said voltage representative of the voltage to be measured being applied via a resistor.