Opamp Characteristics

Question 1

What is mean by Input offset voltage?

Answer 1

Input offset voltage is a parameter defining the differential DC voltage required between the inputs of an amplifier, especially an operational amplifier ,to make the output zero .

Question 2

What is CMRR?

Answer 2

It is ratio of differential voltage gain to common mode voltage gain.Ideally it should be large.For opamp IC741 it is 90 dB.

Question 3

What is slew rate equation in terms of input signal frequency,p eak value of output and it’s unit?

Answer 3

Slew rate = 2π f vp

Unit : V / sec

Question 4

What is UGB and it’s value for IC741?

Answer 4

At some specific value of input signal frequency the value of Aol(f) in dB is zero i.e. it’s numeric value is 1 i,this frequency is called Unity gain bandwidth .For 741 it is 1MHz

Question 5

What is input bias current?

Answer 5

It is average of currents that flow into Inverting and Noninvrerting terminal of opamp