A constant current amplifier stage for a voltage comparator circuit includes a first CMOS transistor pair having a common gate terminal and a common drain terminal and a second CMOS transistor pair which functions as a load for the first CMOS transistor pair. The second CMOS transistor pair has a common gate terminal and a common drain terminal both of which are connected to the common drain terminal of the first CMOS transistor pair. The transistors are configured so that the current through the first transistor pair at null is at least twice the current through the second transistor pair at null voltage.