Adders
Combinational circuits performing binary addition on inputs producing sum and carry outputs. Half adders add two bits. Full adders add three bits (two data plus carry-in). Cascading full adders enables multi-bit addition.
Formula
Half adder: Sum = A XOR B, Carry = A AND B
Real World
The ALU inside an Intel Core i9 processor chains billions of full adders together to perform the integer additions needed for everything from spreadsheet calculations to video rendering.
Exam Focus
Draw and label both the half adder and full adder circuits separately — mixing them up loses marks on diagram questions.
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