Electronics and Communication Engineering - Digital Electronics

31. 

For a 4096 x 8 EPROM, the number of address lines is

A. 14
B. 12
C. 10
D. 8

Answer: Option B

Explanation:

4096 = 212 .


32. 

Assertion (A): A PROM can be used as a synchronous counter

Reason (R): Each memory location in a PROM can be read synchronously.

A. Both A and R are correct and R is correct explanation of A
B. Both A and R are correct but R is not correct explanation of A
C. A is true, R is false
D. A is false, R is true

Answer: Option D

Explanation:

PROM is a memory. It is not a counter.


33. 

A B C D + AB C D =

A. ABC
B. ABCD
C. A B D
D. ABCD

Answer: Option C

Explanation:

A B C D + A B C D = A B D(C + C) = A B D .


34. 

Find the output voltage for 011100 in a 6 bit R-2R ladder D/A converter has a reference voltage of 6.5 V.

A. 6.4 V
B. 2.84 V
C. 0.1 V
D. 8 V

Answer: Option B

Explanation:

(an-1 2n-1 + an-2 2n-2 + .....a121 + a020)

(24 + 23 + 22) = 6.5 x = 2.84 .


35. 

Binary number 1101 is equal to octal number

A. 17
B. 16
C. 15
D. 14

Answer: Option C

Explanation:

1101 = 13 in decimal = 15 (i.e., 8 + 5) in octal.