A circuit for generating a reference current, comprising a positive
feedback loop, a negative feedback loop, and a floating current mirror
coupled to the positive feedback loop. The negative feedback loop may
operate to divert current directly from the floating mirror, and may also
operate to divert current from the floating mirror by using a voltage
follower. The circuit may operate with a minimum supply voltage of
approximately the sum of the threshold voltage of a transistor plus three
drain saturation voltages, in one example.