Patent ID: 7573325

Claim:
A CMOS reference current source comprising: a first circuit branch connected between supply terminals and including a series connection of a bias current source and a first MOS transistor of a first conductivity type; and a second circuit branch connected between the supply terminals in parallel with the first circuit branch, and including a series connection of a diode-connected MOS transistor of a second conductivity type, a second MOS transistor of the first conductivity type and a third MOS transistor of the first conductivity type; and wherein the first MOS transistor of the first conductivity type has its gate connected to the drain of the third MOS transistor of the first conductivity type, the second MOS transistor of the first conductivity type has its gate connected to the drain of the first MOS transistor of the first conductivity type, and the third MOS transistor of the first conductivity type has its gate connected to a bias source; and wherein the bias source for the third MOS transistor of the first conductivity type is provided by the drain node of the first MOS transistor of the first conductivity type.