ELECTRONIC_PROJECTSCIRCUIT • DESIGN • BUILD
Connecting Circuits...
Explore the innovative electronic engineering projects created by our talented students.
The circuit combines two integrated circuits: the 74HC192 BCD up/down counter and the SN7447 BCD-toseven-segment decoder/driver, creating a complete counting and display system.
A smart embedded system designed to measure and display real-time environmental temperature and humidity data. Built using an Arduino Uno microcontroller integrated with a DHT11 sensor for accurate climate reading, and an LCD 16x2 (I2C module) for clear data visualization.
This project is a hardware-based digital clock designed entirely using discrete logic circuits to deliver accurate and reliable performance. Timekeeping precision is achieved using a 32,768 Hz quartz crystal oscillator, with full support for both 12-hour and 24-hour display formats. The clock also integrates advanced features, including a dual normal/stopwatch mode, a hardware-level zero detection circuit for timer functionality, and a multiplexer-driven manual time-setting mechanism for seamless user control
Smart Back Posture Correction Device is a wearable embedded systems project designed to help users maintain a healthy sitting and standing posture by monitoring the angle of the back in real time and providing instant feedback whenever poor posture is detected. Poor posture is one of the most common causes of back pain, muscle strain, fatigue, and long-term spinal problems, especially for students, office workers, programmers, and gamers who spend long hours sitting. This project aims to provide a simple, portable, and low-cost smart solution that encourages users to correct their posture habits continuously throughout the day. Componants Arduino Uno R3 Development Board MPU6050 Motion Sensor Vibration Motor (DC 3.3V) Male-to-Male Jumper Wires ATtiny85 Microcontroller 2N2222 NPN Transistor 1kΩ Resistor (1/4W) 1N4007 Flyback Diode 9V Battery 9V Battery Snap USB Programming Cable The system works using the MPU6050 motion sensor, which contains both a 3-axis accelerometer and a gyroscope. The sensor is attached to the user’s back area to continuously measure tilt and body orientation. The collected motion data is processed by the microcontroller to determine whether the user’s posture is correct or incorrect based on predefined angle thresholds programmed into the system. When the device detects a bad posture position such as excessive slouching or leaning forward for a certain amount of time, it automatically activates a small vibration motor that provides a haptic alert to the user. This vibration acts as a reminder for the user to straighten their back and return to a healthy posture position. Once the posture is corrected, the vibration stops automatically. The project is initially developed and tested using the Arduino Uno R3 development board because it provides an easy platform for prototyping, debugging, and sensor calibration. After testing and optimization, the system is redesigned into a compact wearable version using the ATtiny85 microcontroller to reduce the overall size and power consumption of the final device. Several electronic components are used to build the project, including the MPU6050 motion sensor for posture detection, a DC vibration motor for alerts, a 2N2222 NPN transistor used as a switching element to safely drive the motor, a 1kΩ resistor for current limiting and transistor protection, and a 1N4007 flyback diode to protect the circuit from voltage spikes generated by the motor. The entire system is powered using a portable 9V battery connected through a battery snap connector. During the prototyping stage, all components are connected using a solderless breadboard and jumper wires for easy testing and circuit modifications. The project combines concepts from embedded systems, sensor interfacing, wearable electronics, and real-time monitoring systems. It demonstrates practical applications of motion sensing technology and human-centered electronics design. The final goal of the project is to create an affordable and portable smart posture assistant that can improve user health awareness, reduce bad posture habits, and promote healthier daily sitting behavior.
Gas Detection System This project is a simple gas detection system using an Arduino and a gas sensor. The sensor detects the presence of gas in the air and sends the data to the Arduino. When no gas is detected, the green LED turns on. If gas is detected, the red LED and buzzer are activated to alert the user of a possible gas leak. Components Used: - Arduino Uno - Gas Sensor - Buzzer - Red LED - Green LED
Full-Wave Bridge Rectifier Circuit Project Description This project demonstrates a Full-Wave Bridge Rectifier circuit used to convert Alternating Current (AC) into Direct Current (DC). The circuit uses a transformer to reduce the AC voltage and four diodes connected in a bridge configuration to rectify the input signal. An LED is used as an indicator to show the presence of the DC output. Components Used - Transformer - Four Rectifier Diodes - LED - Resistor - Breadboard - Connecting Wires Working Principle The transformer supplies an AC voltage to the bridge rectifier circuit. During the positive half-cycle of the AC input, two diodes conduct current, while during the negative half-cycle, the other two diodes conduct. As a result, the current flows through the load in the same direction during both half-cycles, producing a pulsating DC output. The LED lights up to indicate that the circuit is functioning properly. Applications - DC Power Supplies - Battery Charging Circuits - Electronic Devices Requiring DC Voltage - Educational and Laboratory Experiments Conclusion The Full-Wave Bridge Rectifier is an efficient circuit for converting AC voltage into DC voltage. It utilizes both halves of the AC waveform, resulting in a higher average output voltage and better efficiency compared to a half-wave rectifier.
A Laser Security Alarm System is a simple electronic project used to detect intruders. The system consists of a laser source, an LDR sensor, a transistor, a resistor, an LED, and a buzzer. The laser beam continuously falls on the LDR sensor. When the beam is interrupted by a person or an object, the resistance of the LDR changes. This change activates the transistor, which turns on the buzzer and LED to give an alarm signal. This project demonstrates the practical use of sensors and electronic switching devices in security applications. It can be used in homes, offices, and educational electronics projects.
دائرة مؤقت تأخير زمني بسيطة (Simple Off-Delay Timer Circuit) تعتمد على فكرة الشحن والتفريغ في منظومة المقاومة والمكثف (RC Network). تُستخدم الدائرة للتحكم في زمن تشغيل ريليه (Relay) لتأخير إيقاف الحمل الكهربائي بعد فصل إشارة التحكم. فكرة العمل: عند الضغط على مفتاح التشغيل، يتم شحن المكثف فوراً ويقوم الترانزستور (BC548) بالانتقال إلى حالة التوصيل (Saturation Mode)، مما يسمح بمرور التيار وتشغيل الريليه. عند رفع اليد عن المفتاح، يبدأ المكثف بتفريغ شحنته ببطء عبر المقاومة (22\text{ K}\Omega) إلى قاعدة الترانزستور (Base)، مما يحافظ على استمرار تشغيل الريليه لفترة زمنية محددة تعتمد على سعة المكثف المستخدم وقيمة المقاومة، حتى تنخفض الشحنة ويتحول الترانزستور إلى حالة الفصل (Cut-off)." المكونات المستخدمة في التصميم (Component List) المفتاح الإلكتروني: ترانزستور NPN طراز BC548. عنصر التحكم الزمني: مكثفات إلكتروليتية بسعات مختلفة (100\mu\text{F}, 220\mu\text{F}, 470\mu\text{F}, 1000\mu\text{F}, 2200\mu\text{F}) لتغيير قيمة الثابت الزمني (\tau = R \times C). مقاومة تحديد تيار القاعدة: بقيمة 22\text{ K}\Omega. خارج الدائرة (Output): ريليه (Relay) للتحكم في الأحمال الكهربائية المعزولة. عنصر الحماية: دايود (Flyback Diode) موصل بالتوازي مع ملف الريليه لحماية الترانزستور من التيارات الراجعة (Back EMF). أزرار التحكم: مفاتيح ضاغطة (Push Buttons) مع دايودات لتوجيه الإشارة.
A circuit that detects rising water levels and lights indicators accordingly, providing a clear visual representation of the tank's water level.
Sound Amplifiering with simple tools (TIP41C Transistor NPN, two Capacitor 47 uF, Speaker, Resistor 2 kohm , 3.5mm Audio jack). This project is used to amplify the sound coming out of the phone or any sound source (microphone, laptop, computer, etc...). A very weak audio signal enters from the JP1 port. The signal passes through capacitor C1 which filters it of any static (DC) electrical charges and leaves only the varying sound waves. These weak waves reach the “base” of transistor Q1. The transistor works like a "water valve". The very small current of sound opens and closes the valve very quickly. This valve controls a much larger current coming from the battery (V1). The large variable current (which is an amplified version of the original audio signal) passes through speaker U1. Transformations of this current cause the speaker cone to vibrate, producing the audible sound.
Sound Amplifiering with simple tools (TIP41C Transistor NPN, two Capacitor 47 uF, Speaker, Resistor 2 kohm , 3.5mm Audio jack). This project is used to amplify the sound coming out of the phone or any sound source (microphone, laptop, computer, etc...). A very weak audio signal enters from the JP1 port. The signal passes through capacitor C1 which filters it of any static (DC) electrical charges and leaves only the varying sound waves. These weak waves reach the “base” of transistor Q1. The transistor works like a "water valve". The very small current of sound opens and closes the valve very quickly. This valve controls a much larger current coming from the battery (V1). The large variable current (which is an amplified version of the original audio signal) passes through speaker U1. Transformations of this current cause the speaker cone to vibrate, producing the audible sound.