DIGITAL ELECTRONICS MCQS PART 09
1. The output of a JK flipflop with asynchronous preset and clear inputs is ‘1’. The output can be changed to ‘0’ with one of the following conditions.
(A)By applying J = 0, K = 0 and using a clock.
(B)By applying J = 1, K = 0 and using the clock.
(C)By applying J = 1, K = 1 and using the clock.
(D)By applying a synchronous preset input.
Ans: C Explanation: Preset state of JK Flip-Flop =1
With J=1 K=1 and the clock next state will be complement of the present state.
2. The information in ROM is stored
(A) By the user any number of times.
(B) By the manufacturer during fabrication of the device.
(C) By the user using ultraviolet light.
(D)By the user once and only once.
Ans: B
3. The conversation speed of an analog to digital converter is maximum with the following technique.
(A) Dual slope AD converter.
(B) Serial comparator AD converter.
(C) Successive approximation AD converter.
(D)Parallel comparator AD converter.
Ans: D
4.A weighted resistor digital to analog converter using N bits requires a total of
(A)N precision resistors.
(B) 2N precision resistors.
(C) N + 1 precision resistors.
(D) N – 1 precision resistors.
Ans: A
5. The 2’s complement of the number 1101110 is
(A) 0010001.
(B) 0010001.
(C) 0010010.
(D) None.
Ans: C Explanation: 1’s complement of 1101110 is = 0010001
Thus 2’s complement of 1101110 is = 0010001 + 1 = 0010010
6. The decimal equivalent of Binary number 10101 is
(A) 21
(B) 31
(C) 26
(D) 28
Ans: A Explanation: 1x2^4 + 0x2^3 +1x2^2 +0x2^1 + 1x2^0 = 16 + 0 + 4 + 0 + 1 = 21.
7. How many two input AND gates and two input OR gates are required to realize Y = BD+CE+AB
(A) 1, 1
(B) 4, 2
(C) 3, 2
(D) 2, 3
Ans: A Explanation: There are three product terms, so three AND gates of two inputs are required. As only two input OR gates are available, so two OR gates are required to get the logical sum of three product terms.
8. How many select lines will a 32:1 multiplexer will have
(A) 5.
(B) 8.
(C) 9.
(D) 11.
Ans: A Explanation: For 32 inputs, 5 select lines will be required, as 25 = 32.
(A)By applying J = 0, K = 0 and using a clock.
(B)By applying J = 1, K = 0 and using the clock.
(C)By applying J = 1, K = 1 and using the clock.
(D)By applying a synchronous preset input.
Ans: C Explanation: Preset state of JK Flip-Flop =1
With J=1 K=1 and the clock next state will be complement of the present state.
2. The information in ROM is stored
(A) By the user any number of times.
(B) By the manufacturer during fabrication of the device.
(C) By the user using ultraviolet light.
(D)By the user once and only once.
Ans: B
3. The conversation speed of an analog to digital converter is maximum with the following technique.
(A) Dual slope AD converter.
(B) Serial comparator AD converter.
(C) Successive approximation AD converter.
(D)Parallel comparator AD converter.
Ans: D
4.A weighted resistor digital to analog converter using N bits requires a total of
(A)N precision resistors.
(B) 2N precision resistors.
(C) N + 1 precision resistors.
(D) N – 1 precision resistors.
Ans: A
5. The 2’s complement of the number 1101110 is
(A) 0010001.
(B) 0010001.
(C) 0010010.
(D) None.
Ans: C Explanation: 1’s complement of 1101110 is = 0010001
Thus 2’s complement of 1101110 is = 0010001 + 1 = 0010010
6. The decimal equivalent of Binary number 10101 is
(A) 21
(B) 31
(C) 26
(D) 28
Ans: A Explanation: 1x2^4 + 0x2^3 +1x2^2 +0x2^1 + 1x2^0 = 16 + 0 + 4 + 0 + 1 = 21.
7. How many two input AND gates and two input OR gates are required to realize Y = BD+CE+AB
(A) 1, 1
(B) 4, 2
(C) 3, 2
(D) 2, 3
Ans: A Explanation: There are three product terms, so three AND gates of two inputs are required. As only two input OR gates are available, so two OR gates are required to get the logical sum of three product terms.
8. How many select lines will a 32:1 multiplexer will have
(A) 5.
(B) 8.
(C) 9.
(D) 11.
Ans: A Explanation: For 32 inputs, 5 select lines will be required, as 25 = 32.
Magme Guru is India's Biggest learning free App for Aspirants who are competing for all government exams with more than 2350+ Subjects and 523+ Exams.
No comments:
Post a Comment