ripple-carry adder , RCA (skrót)

A ripple-carry adder works in the same way as pencil-and-paper methods of addition.

It is the "rippling" of the carry from right to left that gives a ripple-carry adder its name, and its slowness.

This kind of adder is called a ripple-carry adder, since each carry bit "ripples" to the next full adder.

The simplest and (currently) most practical approach is to mimic conventional arithmetic circuits with reversible gates, starting with ripple-carry adders.

A carry-skip adder (also known as a carry-bypass adder) is an adder implementation that improves on the delay of a ripple-carry adder with little effort compared to other adders.

The layout of a ripple-carry adder is simple, which allows for fast design time; however, the ripple-carry adder is relatively slow, since each full adder must wait for the carry bit to be calculated from the previous full adder.