Which of the following amplifiers can be used to create an Operational Amplifier?

Which of the following amplifiers can be used to create an Operational Amplifier?

• A. Single-ended Amplifier
• B. Common Emitter Amplifier
• C. Differential Amplifier
• D. Class A Amplifier

Answer: (C)

The differential amplifier is one of the foundational building blocks of an operational amplifier (op-amp). An op-amp is designed to amplify the difference in voltage between its two input terminals while rejecting any signals that are common to both inputs. This is precisely what a differential amplifier does; it takes two input signals and produces an output that is proportional to the difference between these signals. Differential amplifiers can be implemented using various configurations and components, but their core function is essential for op-amps, which are widely used in various applications including signal conditioning, filtering, and mathematical operations like addition and subtraction. The other types of amplifiers listed do not inherently provide the differential signal processing capability that is vital for an op-amp’s operation. A single-ended amplifier amplifies a single input signal relative to a common ground, which does not allow for the comparison of two input signals. The common emitter amplifier is primarily a type of BJT transistor amplifier configuration, again focusing on one input signal rather than the difference between two. Class A amplifiers refer to a type of biasing for transistors used in amplifiers, but they do not specifically relate to the differential nature of op-amps. Thus, the differential amplifier is correctly identified as the type of amplifier

The differential amplifier is one of the foundational building blocks of an operational amplifier (op-amp). An op-amp is designed to amplify the difference in voltage between its two input terminals while rejecting any signals that are common to both inputs. This is precisely what a differential amplifier does; it takes two input signals and produces an output that is proportional to the difference between these signals.

Differential amplifiers can be implemented using various configurations and components, but their core function is essential for op-amps, which are widely used in various applications including signal conditioning, filtering, and mathematical operations like addition and subtraction.

The other types of amplifiers listed do not inherently provide the differential signal processing capability that is vital for an op-amp’s operation. A single-ended amplifier amplifies a single input signal relative to a common ground, which does not allow for the comparison of two input signals. The common emitter amplifier is primarily a type of BJT transistor amplifier configuration, again focusing on one input signal rather than the difference between two. Class A amplifiers refer to a type of biasing for transistors used in amplifiers, but they do not specifically relate to the differential nature of op-amps.

Thus, the differential amplifier is correctly identified as the type of amplifier