An eight stage ripple counter uses a flip-flop with propagation delay of 75 nanoseconds. The pulse width of the strobe is 50ns. The frequency of the input signal which can be used for proper operation of the counter is approximately ?
Ans. Maximum time occupied for all flip-flops to stabilize is 75ns x 8 + 50 = 650ns. Frequency of operation should be less than 1/650ns = 1.5 MHz.