7483: 4-Bit Full Adder

This is an arithmetic unit that provides the sum of two 4-bit binary numbers. Note the unusual supply connections.

The A number is weighted A1 = 1, A2 = 2, A3 = 4, A4 = 8 and is used as one input.

The B number is weighted B1 = 1, B2 = 2, B3 = 4, B4 = 8 and is used as a second input.

The sum of these two numbers, A and B, appears as Σ1 = 1, Σ2 = 2, Σ3 = 4, and Σ4 = 8.

If the answer exceeds decimal 15 (binary 1111), a 1 also appears on the C4 line as a Carry Output.

When used only with 4-bit numbers, the C0 input should be grounded. When used as the upper 4 bits on an 8-bit number, the C0 input is connected to the C4 output of the previous (less significant) four stages.

Positive logic with 1 being at high level is used.

Pinout
Pin # Pin Assignment
1 Input A4
2 Output Σ3
3 Input A3
4 Input B3
5 Power (+5V)
6 Output Σ2
7 Input B2
8 Input A2
9 Output Σ1
10 Input A1
11 Input B1
12 Ground
13 Input C0
14 Output C4
15 Output Σ4
16 Output B4

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