Patent ID: 7362169

Claim:
A circuit comprising: a first load port and a second load port; a first amplifier comprising an output port coupled to the first load port, the output port having an output voltage Vo 1 (t), the first amplifier further comprising an input port having an input voltage Vin(t); a second amplifier comprising an output port and an input port having an input voltage Vin 2 (t); a capacitive impedance; and a switch to couple the capacitive impedance to the second load port only when the switch is in a first state, the circuit to put the switch into its first state when the output voltage is within an operating range; wherein the first amplifier is coupled to the second amplifier so that [.delta.Vin 2 (t)/.delta.Vin(t)] is substantially equal to the negative of [.delta.Vin 2 (t)/.delta.Vo 1 (t)][G 1 ], where G 1 is the gain of the first amplifier.