ALTERNATING CURRENT AMPLIFIER WITH DIGITALLY CONTROLLED FREQUENCY RESPONSE

摘要

ALTERNATING CURRENT AMPLIFIER WITH DIGITALLY CONTROLLED FREQUENCY RESPONSE An improved A.C. amplifier circuit is disclosed which allows for digital control of the frequency response of the amplifier. A fixed capacitor is serially coupled to a multiplier circuit and the serial combination placed in the feedback path of an operational amplifier circuit. The multiplier provides an output voltage which is proportional to the binary value of a digital control signal and the voltage output of the amplifier circuit. By altering the digital control signal, the effective value of the fixed capacitor may be altered to balance the input capacitance of the amplifier and thereby minimize the effect of the input capacitance on the amplifier frequency response.