Binary Adder
Calculator
Introduction
A digital calculator built from recycled electronic components (E-waste). The system adds two numbers and displays the result on three 7-segment displays.
Using binary counters, digital adder ICs, and display drivers, this project demonstrates practical digital arithmetic while promoting sustainable electronics engineering.
Completed during the First Year – Second Semester Electronics Laboratory.
Project Overview
The calculator generates two numbers via binary counters, adds them through binary adder ICs, converts the result to decimal digits, and drives 7-segment displays for output.
System Block Diagram
Hardware Components
| Component | Function |
|---|---|
| 4029 Counter IC | Generates input numbers (0 to 99) |
| 74283 Binary Adder IC | Performs 4-bit binary addition |
| 7511 Display Driver | Drives 7-segment display segments |
| 7-Segment Displays | Displays final decimal output |
| AND / OR Logic Gates | Binary to decimal conversion logic |
| Recycled Components | ICs, resistors, caps from E-waste boards |
Circuit Design
Two 4029 counter ICs generate the input numbers, each capable of counting from 0 to 99. Their binary outputs feed directly into the addition circuit as the two operands.
Two 74283 4-bit binary adder ICs are cascaded to produce an 8-bit result, covering the full sum range of the two counter inputs.
The 8-bit binary sum is converted to three decimal digits using AND gates, OR gates, and additional adder circuits — producing BCD values suitable for driving the 7511 display driver ICs.
PCB Design
To improve stability and compactness, the full circuit was transferred onto a custom-designed PCB.
E-Waste Component Collection
ICs, resistors, capacitors, and displays were salvaged from discarded electronics, reducing e-waste and demonstrating sustainable engineering practice.
Project Demonstration
Final Output
The completed circuit performs binary addition of two numbers and shows the decimal result across three 7-segment displays.
