# Electronics and Communication Engineering - Digital Electronics

6.
A device which converts BCD to seven segment is called
encoder
decoder
multiplexer
none of these
Explanation:

Decoder converts binary/BCD to alphanumeric.

7.
In 2's complement representation the number 11100101 represents the decimal number
+37
-31
+27
-27
Explanation:

A = 11100101. Therefore A = 00011010 and A' = A + 1 = 00011011 = 16 + 8 + 2 + 1 = 27. Therefore A = -27.

8.
binary states 1000 to 1111
binary states 0000 to 0011
binary states 1010 to 1111
binary states 1111 to higher
Explanation:

A decade counter counts from 0 to 9. It has 4 flip-flops. The states skipped are 10 to 15 or 1010 to 1111.

9.
BCD input 1000 is fed to a 7 segment display through a BCD to 7 segment decoder/driver. The segments which will lit up are
a, b, d
a, b, c
all
a, b, g, c, d
Explanation:

1000 equals decimal 8 Therefore all segments will lit up.

10.
A ring counter with 5 flip flops will have
5 states
10 states
32 states
infinite states