an enhanced output impedance current mirror in which the operational amplifier includes a set of four mosfets having a common gate that is connected to a drain terminal of one of the differential pairs . two of the mosfets reside in parallel in the current path of each of the mosfets of the differential pair . the differential pair mosfet that has its drain terminal connected to the common gate also has a gate terminal that is connected to the common node between the two other mosfets in its current path .