Draw the circuit diagram of Asynchronous decade counter and explain its working.
Ans:
To design a circuit diagram of decade asynchronous counter initially we draw the circuit for MOD 16 asynchronous counter that counts from 0 to 15 by using four flip-flop (JK or T flipflop). This must count from 0 to 9 and then come to 0. The initial state to be skipped is 1010 (10) here Q3 and Q1 are 1 and Q2 and Q0 are 0 if we obtain Q3 and Q1 and applied these to a NAND gate after that the output of the NAND gate will be low only where Q3 and Q1 are high. Such signal can be utilized to asynchronously clear all flipflops to make the counting state 0000. In this method MOD 16 counter will be limited to count 10 states i.e. from 0 to 9.
The circuit diagram of Asynchronous decade counter