Compensated gain-controlled amplifier having a wide linear dynamic range

摘要

A high dynamic range linear automatic gain control (AGC) circuit that has independent means for temperature compensation. The temperature compensation circuit of this invention can be used in a closed-loop AGC circuit such as is required in a transceiver for compensating the gains of receiver and transmitter amplifiers to ensure that both track closely over ranges of temperature, frequency and load impedance. The temperature compensation signal is coupled to one of the two gates in a field effect transistor (FET) amplifier to maintain a constant gain function over ranges of temperature, frequency and load impedance. Thermal compensation for the transmitter amplifier is derived from the thermal compensation signal for the receiver amplifier.