The clock period of a ripple counter must be longer than the total propagation
delays through all of the flip-flops. For proper operation, the period / frequency
should be:
Tmin = N x tpd where tpd is the propagation delay fmax = 1/ Tmin = 1/ (N x tpd).
If the propagation delay is 15ns for a J-K FF, what is the largest
MOD counter that can be constructed to ensure the counter will operate for
frequencies > 12 MHz?
