# JNTU, B Tech,i Semester Linear And Digital Ic Application, November 2008

JNTU PAPERS

, B.Tech,I-Semester LINEAR AND DIGITAL IC APPLICATION, November 2008

( Computer Science & Engineering, Information Technology and Computer Science & Systems Engineering) SET-2

1. (a) Define the terms : SVRR,CMRR, input bias current, input offset voltage,

Gain Bandwidth product [10]

(b) What are the differences between the inverting and non inverting terminals?

What do you mean by the term ‘’virtual ground‘’? [6]

2. (a) What is Gyrator circuit? Explain its operation with a neat circuit diagram [6]

(b) What is a sample and hold circuit? Why is it needed? With neat circuit diagram, describe the operation of an OP-AMP based sample and hold circuit.

[10]

3. (a) What feedback is preferred for oscillators and why? What is the effect of negative feedback? [8]

(b) Design an OP-AMP based relaxation oscillator and derive the frequency of oscillation. [8]

4. (a) Explain the functions of each of pins in 555 timer. [8]

(b) List the important features of 555 timer. [8]

5. (a) Draw the circuit of a PLL AM detector and explain its operation. [10]

(b) What is the major difference between digital and analog PLLs? [6]

6. (a) Explain the design procedure (with suitable circuit diagram of a fourth order

Butterworth low-pass filter). [10]

(b) A certain narrow band-pass filter has been designed to meet the following

specifications: fC=2kHz. Q=20, and Ap=10. What modifications are necessary in the filter circuit to change the center frequency ‘fc’ to 1kHz, keeping

the gain and band-width constant? [6]

7. (a) Draw the circuit of a Totem-pole TTL NAND gate? What is the purpose of

using a diode at the output stage? Explain its operation and verify the truth

table. [8]

(b) When do we use open-collector TTL gate? [4]

(c) Which is the fastest logic gate and why? [4]

8. (a) What is a sample-and-hold circuit? Draw the circuit diagram and explain its

action? [6]

(b) With reference to sample and hold circuit define the following terms: [4]

i. Aperture time

ii. Hold mode.

(c) Draw the circuit of Weighted Resistor DAC and derive expression for output

analog voltage Vo. [6]