O'Reilly logo

Digital Logic Design: A Rigorous Approach by Moti Medina, Guy Even

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

CHAPTER 17

Flip-Flops

So far we have focused only on combinational circuits. It is time to deal with circuits that have a memory. Memory, in principle, means that the output depends not only on the input but also on the history. However, if we wish to refer to the history, then we need a notion of time. So before we consider a memory device, we must address the issue of time.

Time in digital logic is defined by a special signal called the clock. The clock signal is not a clock in everyday terms; it is simply a periodic signal that alternates between zero and one. The alternations help us partition time into disjoint intervals, called clock cycles.

Bits are stored in a special memory device called a flip-flop. The definition of flip-flops ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required