Opamp Basics

Question 1

What is DIBO amplifier?

Answer 1

It is input stage of opamp; uses 2 identical CE amplifier,Vo taken between collectors and input at base of 2 transistors.

Question 2

Describe nature of transfer curve of opamp.

Answer 2

Vo proportional to V1-V2 till reaches positive or negative saturation voltage,thereafter Vo remains constant.These saturation voltages are specified by Vo of opamp for given supply voltages.

Question 3

Voltage series feedback amplifier using opamp is also known as ______.State voltage gain for this circuit.

Answer 3

Noninverting amplifier with feedback.

Af= 1 + ( Rf / R1)

Question 4

Voltage shunt feedback amplifier using opamp is also known as ______. State voltage gain for this circuit

Answer 4

Inverting amplifier with feedback.

Af= - ( Rf / R1)

Question 5

For Noninverting amplifier what is Rif and Rof?

Answer 5

Rif = Ri (1 + A B)

Rof = Ro / (1 + AB)

Question 6

For Inverting amplifier what is Rif and Rof?

Answer 6

Rif = Ri

Rof = Ro / (1 + AB)

Question 7

Application ckt of Noninverting amplifier.

Answer 7

Voltage follower

Question 8

Application ckt of Inverting amplifier.

Answer 8

Current to Voltage converter

Question 9

Open loop opamp is used for what type applications?

(linear or Nonlinear)

Answer 9

Nonlinear applications

Question 10

Types of feedback. What are advantages of negative feedback

Answer 10

Positive & Negative Negative feedback classified as Vtg series,Vtg shunt,current series,current shunt. Advantages of negative feedback: Gain stabilization, increases bandwidth,d decrease in distortions and offset voltage