Arithmetic Circuits

Equality Comparator

• compares whether or now two n-bit binary numbers are equal

• uses XNOR gates, which are 1 when both inputs are equal

Half Adder

• performs binary addition on two bits

• output is a sum bit and carry bit

• one XOR and AND gate

Full Adder

addition with an input carry bit

Ripple-Carry Adder

• adds two n-bit integers (n is width)

Ripple-Carry Adder Structure

• LBS is handled by a half-adder

• other additions are performed using full adders

• final carry output detects overflows