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Advanced (A Level)


18 - Boolean Logic


13 - Full adders

Full Adder

A full adder adds binary numbers and accounts for values carried in as well as out. A one-bit full-adder adds three one-bit numbers, often written as A, B, and Cin; A and B are the operands, and Cin is a bit carried in from the previous less-significant stage.[2] The full adder is usually a component in a cascade of adders, which add 8, 16, 32, etc. bit binary numbers. The circuit produces a two-bit output. 


Full adder in action. A full adder gives the number of 1s in the input in binary representation.

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