Patent ID: 7190178

Claim:
A system comprising: (a) a variable gain amplifier having a first input terminal coupled to receive a first input signal, the amplifier further having a first output terminal for outputting a first output signal that is a function of the first input signal, and a gain control terminal controlling a variable gain applied to the first input signal; (b) a first summer, operatively coupled to the first output terminal for adding a first offset signal to the first output signal, the first summer having a second output terminal; (c) a first multiplier, operatively coupled to the second output terminal, the first multiplier having a feedback factor terminal for receiving a proportional feedback factor signal and the first multiplier having a third output terminal for outputting a multiplied feedback signal representing the offset first output signal multiplied by the proportional feedback factor signal; (d) a second summer, operatively coupled to the third output terminal, for adding a second offset signal to the multiplied feedback signal, the second summer having a fourth output terminal; and (e) a second multiplier, operatively coupled to the fourth output terminal, the second multiplier having a gain factor terminal for receiving a gain factor signal and the second multiplier having a fifth output terminal for outputting a multiplied gain signal representing the output of the fourth output terminal multiplied by the gain factor signal; wherein the gain control terminal of the variable gain amplifier is operatively coupled to the fifth output terminal.