VIN Technologies › Labs › Digital Systems Lab

Full adder

Digital Systems Lab · free online experiment, runs in your browser with no install or sign-up.

Open this experiment in the circuit simulator

Objective

Add two bits and a carry-in; verify SUM and COUT against binary addition for all 8 input combinations.

Procedure

  1. Run through all 8 combinations.

Theory

SUM = A ⊕ B ⊕ CIN and COUT = majority(A, B, CIN). The pair (COUT, SUM) is the binary number A + B + CIN.

Questions to answer

  1. How do you build a 4-bit adder from full adders?

Components used

Full adder, 2 × Logic probe / LED, 3 × Logic switch

About the model

Ideal wires; component models as listed in the catalogue (no parasitics, no temperature drift). Built without a breadboard so the schematic stays readable.

Open this experiment in the circuit simulator

More Digital Systems Lab experiments