A 1 V, 380nW, Current Generator Circuit using Sub-Threshold Region of Operation of MOSFETs

In Analog circuit design field, current reference circuit is mostly used for constant current supply to the circuits, so that their function runs properly. This work gives a circuit that operates with minimum operating voltage and current, CMOS current generator circuit and presents its performance with circuit simulation in 180nm UMC CMOS technology. The designed circuit has four sub parts start-up, Bias-voltage, current-source sub-circuits, voltage generator circuit, with most of the MOSFETs operating in sub-threshold region. Simulation results shows that the circuit gives a constant reference current of 4-nA at supply voltage 1 V with line variation of 0.203%/