# Binary Ripple Counter in Digital Electronics

A counter that follows the binary sequence is called a binary counter. A binary ripple counter consists of a series of complementing flip flops (T or JK FF) with the output of each flip flop connected to the clock pulse input of the next higher order flip flop. The flip flop holding the least significant bit receives the incoming count pulses.

It is known as ripple counter because the flip flops change one at a time in rapid succession and the signal propagates through the counter in a ripple fashion. CLK is coming for subsequent flip flops from previous flip flops and change state only when transition of previous flip flop’s output is from high to low i.e. from 1 to 0.

The lowest order bit Q0 gets complimented with each count pulse. Every time Q0 goes from 1 to 0, it complements Q1. Every time Q1 goes from 1 to 0, it complements Q2 and so on.

A complimentary flip flop can be obtained in 3 ways as described below:

1. Using T Flip Flop
2. Using JK Flip Flop with J & K inputs tied together
3. Using D Flip Flop with the complement output connected to the D input. In this way the D input is always the complement of the present state and next clock pulse will cause the flip flop to complement.
 CLK Q3 Q2 Q1 Q0 0 0 0 0 0 1 0 0 0 1 2 0 0 1 0 3 0 0 1 1 4 0 1 0 0 5 0 1 0 1 6 0 1 1 0 7 0 1 1 1 8 1 0 0 0 9 1 0 0 1 10 1 0 1 0 11 1 0 1 1 12 1 1 0 0 13 1 1 0 1 14 1 1 1 0 15 1 1 1 1

Mod of Binary Ripple Counter = 2n,, where n is the number of flip flops

The counter counts in a binary sequence from 0 to 2n-1