6.4: 2-Bit Adder Circuit
- Page ID
- 52382
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The full adder forms the basis for all arithmetic in a CPU. To illustrate this, a 2-bit adder is represented in Logisim in the Figure \(\PageIndex{1}\). This adder is implemented by using two instances of the 1-bit adder, and connecting the Cout from the first adder to the Cin of the second adder The adder shown below is adding X=112 (310) plus Y = 012 (110), resulting in 1002 (410), as expected. To create a n-bit adder (for example, a 32 bit adder used in many modern CPUs), 32 full adders can be wired together in a series, with the Cout of each bit being connected to the Cin of the next bit.
