Abstract: A reference circuit includes: (a) a first reference circuit having a reference signal and a ?VBE loop; and (b) a modification circuit using a first voltage to change a first current in the ?VBE loop of the first reference circuit. In one embodiment, the reference circuit is a voltage reference circuit.

Abstract: Prior art differential track and hold amplifiers produce an error voltage when transitioning from a track mode to a hold mode. An error voltage limits the resolution of a track and hold amplifier. A first circuit (44) and a second circuit (45) couple a differential voltage to the storage capacitor. Control signals applied to the first and second circuits (44, 45) generate parasitic currents through parasitic capacitances which couple to a storage capacitor of a track and hold amplifier (41). The control signals applied to the first and second circuits (44, 45) are forced to transition an equal voltage magnitude to produce identical parasitic currents through the parasitic capacitance. Identical parasitic currents affect common mode voltage but do not change the differential voltage stored on the storage capacitor. A clamping circuit (50) clamps the voltage transition of the control signals to produce identical voltage transitions.