E7G12 : What is an operational amplifier?
A
A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
B
A digital audio amplifier whose characteristics are determined by components external to the amplifier
C
An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
D
A RF amplifier used in the UHF and microwave regions
Correct Answer: A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance