3 Bit Synchronous Down Counter

It contains introduction to 3 bit synchronous down counter. Through these slides you will have a complete understanding of synchronous down counter.

1. 3 bit synchronous down counter 1 Presented by: Rabin BK BSc.CSIT 2 nd Semester

2. CONTENTS Introduction to Counter 3 bit synchronous down counter References 2

3. A sequential circuit that goes through a prescribed sequence of states upon the application of input pulses Input pulses may originate from external sources and occur at defined interval or at random Counter is found in almost all the digital logic for counting the number of occurrences of an event Useful for generating timing sequences to control operations in digital system An n bit binary counter counts from 0 to 2 n -1or vice-versa and consists of n flip-flops 3 Introduction to Counter

4. A ll the flip-flops receive the same clock signal , so it is called as Synchronous counter Since it counts from 2 3 -1 = 7 to 0 , it is called down counter Consists of 3 T flip-flops and one 2-input AND gate All the flip-flops are negative edge triggered and the outputs of flip-flops change (affect) synchronously The T inputs of first, second and third flip-flops are 1, , respectively   4 3 bit synchronous down counter T flip-flops

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6. R eferences Books reference Digital Logic and Computer Design, M. Morris Mano Web reference: https:// www.tutorialspoint.com/digital_circuits/digital_circuits_counters.htm 6

7. Queries 7