Question

You are required to design a counter using D flip-flops with the following count sequence:

A B C will be used to represent the bits in the present count'state, where A is the MSA and C
is the LSB.
A+ B+ and C+ will be used to designate the bits in the next count.
In the state table, Don't Cares should be used for the unused count transitions.
The following questions are based on the different aspects of that design.
Grading comment: How many D flip-flops are needed to store the count sequence?

a)1
b)2
c)3
d)4

Answer 1

A total of three D flip-flops are required to store the count sequence A, B, C. Option (c) is true.

Step-by-step explanation:

The explanation is based on the fact that each flip-flop in the counter design represents one bit of the count sequence.

In this scenario, the count sequence is represented by A, B, and C, where A is the most significant bit (MSB) and C is the least significant bit (LSB).

A flip-flop for A: One flip-flop is needed to store the state of bit A.

A flip-flop for B: Another flip-flop is needed to store the state of bit B.

A flip-flop for C: Yet another flip-flop is needed to store the state of bit C.

The concept used here is that each bit in a binary count sequence requires one flip-flop to store its state.

This is based on the binary nature of counting, where each bit represents a power of 2 (1, 2, 4, 8, etc.).

So, a total of three D flip-flops are required to store the count sequence A, B, C.

Thus, Option (c) is true.