Patent ID: 8233869

Claim:
A method, comprising the steps of: providing an input signal for a first amplifier; and generating first and second control signals, said first control signal controlling a gain of said first amplifier in response to a magnitude of said input signal and said second control signal controlling a gain of a second amplifier coupled to said first amplifier in series in response to said magnitude of said input signal, wherein: said first control signal remains substantially unchanged at a first level while said magnitude of said input signal is within a first range, said first control signal remains substantially unchanged at a second level while said magnitude of said input signal is within a second range in which said magnitude of said input signal exceeds said magnitude of said input signal in said first range, said gain of said first amplifier in said second range is substantially lower than said gain of said first amplifier in said first range, said first control signal changes with a first variable level in a third range in which said magnitude of said input signal exceeds said magnitude of said input signal in said second range, said gain of said first amplifier in at least a part of said third range is gradually reduced, said gain of said first amplifier in said third range is substantially lower than said gain of said first amplifier in said second range, said second control signal changes with a second variable level in said first range, said gain of said second amplifier is gradually reduced, said second control signal changes with a third variable level in said second range, said gain of said second amplifier is gradually reduced, said second control signal remains substantially unchanged at a third level in said third range.