Experiment 1 - The 1-bit Counter

To understand counters, you first look at a simple 1-bit counter.

A 1-bit counter is composed of a single T flip-flop. A T flip-flop stores one bit. With a signal to the Data IN the T flip-flop counts from 0 to 1. With a further signal it reverts again to 0.

Circuit diagram of a 1-bit counter consisting of a T flip-flop.

Illustration states of the 1-bit counter.

In practice, you use a JK flip-flop that you can easily transform into a T flip-flop...

Circuit diagram of a 1-bit counter consisting of a JK flip-flop.

Circuit 1-bit counter with JK flip-flop. (Enlarge)

Circuit diagram - Circuit

In the further experiments T flip-flops are used in all circuit diagrams, whereas in the circuits JK flip-flops are used.

This serves to make the circuit diagrams as clearly as possible...

Practical Note

In the circuits you are using C-MOS4027 with two combined JK/RS flip-flops. To make sure that the circuit works correctly, you must set both R and S to 0!

In the next experiment, you build a 2-bit counter...

Experiment 2 - 2-bit Counter