A flip-flop has a 20-nano second delay from the time its CP input goes from 1…

2017

A flip-flop has a 20-nano second delay from the time its CP input goes from 1 to 0 to the time the output is complemented. What is the maximum delay in a 16-bit binary ripple counter that uses these flip-flops?

  1. A.

    20 ns

  2. B.

    320 ns

  3. C.

    36 ns

  4. D.

    16 ns

Attempted by 83 students.

Show answer & explanation

Correct answer: B

In a binary ripple (asynchronous) counter, flip-flops are connected in a chain. The clock pulse cascades sequentially from one stage to the next. Therefore, the propagation delays of all individual flip-flops accumulate linearly to create the worst-case maximum total delay.

Formula:

Maximum Total Delay = n x tpd

Given data:

  • Number of bits/stages (n) = 16

  • Propagation delay per flip-flop (tpd) = 20 ns

Substituting the values:

Maximum Total Delay = 16 x 20 ns =320 ns

Thus, the correct option is B.

Explore the full course: Coal India Management Trainee