GATE Electrical Engineering - Complete Master Library

 

GATE Electrical – Analog Electronics

Practice Problems – Page 14

This section contains problems based on Operational Amplifier Applications including summing amplifier and difference amplifier circuits.

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Problem 131

Question:

What is a summing amplifier?

Answer:

A summing amplifier is an op-amp circuit that produces an output voltage proportional to the sum of multiple input voltages.

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Problem 132

Question:

Write the output equation of an inverting summing amplifier.

Answer:

Vo = −Rf (V1/R1 + V2/R2 + V3/R3)

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Problem 133

Question:

If Rf = 10 kΩ, R1 = R2 = 5 kΩ, V1 = 1 V, V2 = 2 V, find output voltage.

Solution:

Vo = −Rf (V1/R1 + V2/R2)

Vo = −10k (1/5k + 2/5k)

Vo = −6 V

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Problem 134

Question:

What is a difference amplifier?

Answer:

A difference amplifier amplifies the difference between two input signals.

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Problem 135

Question:

Write the output voltage equation of a difference amplifier.

Answer:

Vo = (Rf/R1) (V2 − V1)

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Problem 136

Question:

If Rf = R1 and V2 = 4 V, V1 = 1 V, calculate output voltage.

Solution:

Vo = (V2 − V1)

Vo = 4 − 1 = 3 V

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Problem 137

Question:

Which op-amp circuit performs addition of signals?

Answer:

Summing Amplifier

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Problem 138

Question:

Which op-amp circuit is used for signal subtraction?

Answer:

Difference Amplifier

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Problem 139

Question:

Where is summing amplifier commonly used?

Answer:

Audio mixers and signal processing circuits.

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Problem 140

Question:

Which op-amp application is used in digital to analog converters?

Answer:

Summing Amplifier