ripple_counter
Asynchronous (ripple) counters
Basic idea of counters
Asynchronous (ripple) counter using JK flip-flops
counting through binary power (e.g. 24 = 16 states, 0–15) counting through an arbitrary range (e.g. 0–9, decade counter)Effect of propagation delay
causes clock to ‘ripple’ through counter
causes the system to pass through wrong states (briefly)
hence ripple counters are used only for undemanding applications where the timing is not critical
Other types of asynchronous counters can also be made
down counters, for example
