Question

The minimum number of flip-flops required to design a mod-10 counter is:

• A. 3
• B. 4
• C. 5
• D. 10

Hint:

Use \( 2^n \geq \text{MOD} \) to determine flip-flop count for counters.

Answer 1

The Correct Option is B

To determine the minimum number of flip-flops required to design a mod-10 counter, we must consider the properties of binary counters: A mod-N counter requires enough flip-flops to represent at least N different states.

The number of flip-flops (n) required is determined by the formula: 
2ⁿ ≥ N

For a mod-10 counter, N = 10. We solve for n:
 

• 2³ = 8 (not enough, because 8 < 10)
• 2⁴ = 16 (sufficient, because 16 ≥ 10)

Thus, the minimum number of flip-flops required is 4.

Flip-flops (n)	2n Values
3	8
4	16