SRM University 2007 B.Tech Information Technology ELECTRONIC DEVICES AND CIRCUITS - Question Paper

45. Define the term slew rate
46. Define CMRR for an opamp?
47. Define unity gain bandwidth of an opamp.
48. What is meant by drift as applied to an opamp.
49. For an opamp having a slew rate of two volts/µsec what is the maximum closed loop voltage gain that can be used when the input signal varies by 0.5 volt in 10µsecs.
50. The voltage gain of an opamp is 80dB when its bandwidth is 20Hz. obtain its unity gain bandwidth
51. An opamp has a differential gain of 60dB and common mode gain of 40dB. obtain CMRR.
52. Given output voltage of an opamp is –90V1 + 90.09V2. obtain CMRR.


TEN MARKS

1.
(i) Draw block diagram representation of an opamp and discuss every block in detail.
(ii) Explain briefly the classification and advantages of IC’s.
2.
(i) Sketch the pin diagram for an operational amplifier in metal can and DIP IC packages. Identify all terminals and briefly discuss.
(ii) Sketch the input output stages of a bipolar operational amplifier. discuss the circuit operation and explain the input and output impedances.
3. Derive an expression for gain of an inverting, non-inverting and difference amplifier configurations.
4.
(i) Sketch the basic operational amplifier circuit with the external connection for non-inverting amplifier operation. discuss how the circuit amplifies the signal.
(ii) Briefly discuss the characteristics of an ideal opamp.

5.
(i) Sketch a circuit diagram for an inverting amplifier. Identify all the terminals and discuss the circuit operation
(ii) What is meant by input offset voltage and input offset current in an opamp.
6. Sketch the circuit of an opamp difference amplifier. discuss its operation and derive an formula for the output voltage in terms of the input and the circuit components.
7. Discuss briefly about voltage follower and inverter circuits.
8. With a neat diagram discuss the operation of an inverting and non-inverting summer
9. Sketch a 3 input summing amplifier circuit and discuss its operation.
10. Explain the differentiator circuit with a neat diagram. Also derive an expression for the output voltage.
11. Explain the opamp based Integrator circuit with a neat diagram. Also derive an expression for the output voltage.
12. Explain the subsequent with a neat sketch
(i) V to I converter with floating loads.
(ii) V to I converter with grounded loads.
13.
(i) What is CMRR? Derive an expression for Ac, Ad in terms of A1, A2 and hence derive CMRR.

Earning:   Approval pending.