MAC Unit

• In computing, especially digital signal processing, the Multiply–Accumulate (MAC) or Multiply–Add (MAD) operation is a common step that:
• Computes the product of two numbers.

• Adds that product to an accumulator.

• The MAC operation modifies an accumulator y:

y ← y + (a × b)

For simplicity, in C code:

y += (a * b);

• General CPUs are used in Von Neumann architecture, but digital signal processors (DSPs) use MACs.
• The hardware unit that performs the operation is known as a Multiplier–Accumulator (MAC Unit).