Question

n stage ripple counter can count up to

• A. $2^n$
• B. $2^n$ - 1
• C. n
• D. $2^{n-1}$

Answer 1

The correct option is B $2^n$ - 1

n stage ripple counter can count up to 2^n-1.

A ripple counter is an asynchronous counter where only the first flip-flop is clocked by an external clock. All subsequent flip-flops are clocked by the output of the preceding flip-flop. Asynchronous counters are also called ripple-counters because of the way the clock pulse ripples it way through the flip-flops. The MOD of the ripple counter or asynchronous counter is 2^n if n flip-flops are used.