A current generator includes first and second current generators and an output current generator. The first current generator has an output for providing a first current, the first current proportional to a difference between a first power supply voltage and a first gate-to-source voltage. The second current generator has an output for providing a second current, the second current proportional to a second gate-to-source voltage. The second gate-to-source voltage is approximately equal to the first gate-to-source voltage. The output current generator provides an output current proportional to a sum of said first current and said second current.