a method of gain control by amplifying an input signal with a variable gain amplifier to generate an output signal where the gain of the variable gain amplifier is selected based upon a control signal presented at a control input of the variable gain amplifier . when the output signal is larger than the upper boundary , incrementally changing the magnitude of the control signal so as to reduce the gain of the variable gain amplifier in a step - wise linear fashion . when the output signal is smaller than the lower boundary , incrementally changing the magnitude of the control signal so as to increase the gain of the variable gain amplifier in a step - wise linear fashion .