Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
using 2 halfadders u can implement a fulladder.
connect 2 inputs to first halfadder, and connect the 3rd input and the "SUM" output of the first halfadder to the second halfadder. the "SUM" result of the 2nd halfadder will be a fulladder "Sum" output. Use an OR gate to get the "carry" out signal. Connect the "carry" out of the first and second halfadders to that OR gate to get the Full adder "Carry" out.