Question

Explain the working of a four bit synchronous up counter using relevant diagrams.

Answer 1

Counter is a logic circuit used for counting the pulses. It is a set of flip flops whose state changes in response to pulses applied to their inputs.

Counters are of two types:

(i) Synchronous counters and

(ii) Asynchronous counters.

After Clock pulse	Status of Counter Q1	Q2	Q3	Q4
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

In a synchronous circuit, the clock signal is applied to all flip flops simultaneously.