Tag: Sequential Circuits

Up to now, every circuit that was presented was a combinatorial circuit. That means that its output is dependent only by its current inputs. Previous inputs for that type of circuits have no effect on the output. However, there are many applications where there is a need for our circuits to have “memory”; to remember…

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What is a Synchronous Counter? A synchronous counter, in contrast to an asynchronous counter, is one whose output bits change state simultaneously, with no ripple. The only way we can build such a counter circuit from J-K flip-flops is to connect all the clock inputs together, so that each and every flip-flop receives the exact…

In the previous section, we saw a circuit using one J-K flip-flop that counted backward in a two-bit binary sequence, from 11 to 10 to 01 to 00. Since it would be desirable to have a circuit that could count forward and not just backward, it would be worthwhile to examine a forward count sequence…

If we examine a four-bit binary count sequence from 0000 to 1111, a definite pattern will be evident in the “oscillations” of the bits between 0 and 1: Note how the least significant bit (LSB) toggles between 0 and 1 for every step in the count sequence, while each succeeding bit toggles at one-half the…