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What is a printed circuit board PCB?

A Printed Circuit Board or PCB is essentially a board that connects electronic components. It is the basic building block of any electronic design.

Types of circuit board

Kinds of circuit boards include single-sided circuit boards, double-sided circuit boards, multilayer circuit boards, and flexible boards.

Basic Components of a circuit board.

An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow.

Why is a circuit board green?

If the PCB itself is green, that indicates, that its made from glass-epoxy which is naturally green.

 What is a Substrate?

Most printed circuit boards are built in layers. The middle layer is the base material, also called the substrate. Depending on the material of the substrate, PCBs can be either rigid or flexible. 

What is PCB Soldering Process?

Wave soldering is a large-scale soldering process by which electronic components are soldered to a printed circuit board (PCB) to form an electronic assembly.

What is PCBA manufacturing?

A circuit board prior to assembly of electronic components is known as PCB. Once electronic components are soldered, the board is called Printed Circuit Assembly (PCA) or Printed Circuit Board Assembly (PCBA). 

Simple Arduino Uno Circuit glowing LED when push button is pressed.


Arduino code for glowing led on push button click

void setup() {

pinMode(2, INPUT_PULLUP);
pinMode(13, OUTPUT);


void loop() {
int sensorVal = digitalRead(2);

if (sensorVal == HIGH) {
digitalWrite(13, LOW);
} else {
digitalWrite(13, HIGH);

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Focus on Multilayer PCB 4-50L, HDI PCB 5-7 Days & PCB Assembly


Build 0201,30um/QFP,0.3mm BGA , AOI ,X-RAY and Coating in House


Focus on Multilayer PCB 4-50L, HDI PCB 5-7 Days & PCB Assembly


Build 0201,30um/QFP,0.3mm BGA , AOI ,X-RAY and Coating in House


Circuit boards manufacturers, printed circuit boards manufacturers, printed circuit board assembly.



Turn-key PCB Assembly: Bittele Electronics is a low-cost, turnkey, PCB assembly service provider for prototype and low-volume, electronic contract manufacturing.




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Electronics Circuits & Schematics


Simple Electronics projects circuits for Beginners

5 beginners projects that work in the first attempt | Build Circuit


Simple electronics projects and small basic hobby projects/circuits



Simple Electronic Circuit

555 Timer Circuit +5V TO +15V

Burglar Alarm Circuit

Light Dark Detector Circuit

Fire Alarm Circuit

Rain Alarm circuit


Op amp circuit

USB Battery Charger Circuit

Touch Sensor Circuit

Power Failure Circuit

Vibration Motion Sensor Circuit

555 Timer LED Flasher Circuit

Lamp Dimmer TRIAC DIAC Circuit

AC TO DC Converter

RS232 Circuit


Current Boosting Circuit



Electronic components manufacturers list


List of top semiconductor manufacturers in the world.


Free electronic circuit design and simulation softwares links -123circuits.com

  1. SchemeIt:www.digikey.com/schemeit

  2. CircuitMaker: http://circuitmaker.software.informer.com/6.2/

  3. Electronic Circuit Designer: http://www.electronics-lab.com/downloads/schematic/

  4. CircuitLogix: https://www.circuitlogix.com/student_version.php

  5. Schematic and PCB Design Software: www.ibfriedrich.com

  6. Design software: www.electronics-project-design.com/free-electronics-design-software.html

  7. Multisim: www.ni.com/multisim

  8. SmartDraw:www.smartdraw.com/software/electrical.asp

  9. PCB design software :www.cadsoftusa.com

  10. Simulation Software: www.smps.us/tools.htm

  11. Electronic Design Automation: www.altium.com

  12. LogicCircuit : www.logiccircuit.org

Useful Links

PCB Manufacturing and Assembly

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PCB Assembly

Printed circuit board fabrication

Order PCB

Download Electronic Circuits, Free Electronic Circuits for Hobbyist

·    555 Timer Tutorial - An extensive tutorial on 555 timer (history, timing and logic diagrams, replacement guide).

 Bowden's Hobby Circuits - A collection of electronic circuits for the hobbyist or student, links to related sites, commercial kits and projects, newsgroups and educational areas.

 Building Gadgets - A collection of electronics projects, circuits, datasheets, and helpful articles from the authors of "Electronics Projects For Dummies".

 Butterworth Low-Pass Filter - Design of a 5th order Butterworth LP filter using Sallen-Key circuit design.

 Circuit Cellar Archive - Nearly every issue is listed from 1988 to 2001, software code.

 CircuitDB - A searchable database of schematics and electronic circuit designs such as alarms, audio/video, auto, etc.

 Circuits Archive - ASCII circuit diagrams, radio, audio and computer related circuits; data sheets.

 Circuits Today - Collection of circuits built around specific components and functions

 CircuitsArchive - A Wiki-based archive of electronic circuits for hobbyists.

 Closed Caption Decoder - A simple closed caption decoder for your TV. Schematic, BOM, theory of operation.

 CoolCircuit - Electronic circuits, projects, schematics, and software for hobbyists.

 CXI Schematics - Schematic index: audio, RF, power, switching and miscellaneous circuits.

 Delabs Electronic Schematic Diagrams - Electronic circuit archive, FAQ, freeware, resources directory.

 Digital Clock - Easy nixie clock with different microcontrollers.

    Discover Circuits - A collections of categorized and cross-referenced electronic circuits or schematics.  

·   Electro Tech Electronic Projects - An electronic forum. Includes a collection of small electronic circuits.

·   Electronic Circuit Diagrams - Schematics with descriptions and do-it-yourself electronic projects for hobbyists.

·   Electronic Circuit Projects - A circuit archive with schematics, descriptions and PCB layouts.

    Electronic Circuit Projects - Electronics projects, schematics,PCB tips for high school students, teachers, students, and hobbyists.

    Electronic Circuits - An archive of electronic circuits divided into categories such as power supplies, auto, computer circuits, sound/radio.

    Electronic Circuits - Electronic circuit diagrams, software, tutorial, schematics, projects, and tools.

    Electronic Circuits and Microcontroller Projects - A collection of electronics circuits, microcontroller projects, and tutorials for hobbyists.

    Electronic Circuits Directory - A collection of electronic schematics and projects, index of tutorials and design software.

    Electronic Circuits for Beginners - Site with simple circuits that are easy for beginners in electronics to build and understand

    Electronic Circuits for the Hobbyist - Electronics projects, schematics, and tutorials: high voltage, radio control, timers, oscillators, RF transmitters, amplifiers and other.

    Electronic Info and Schematic Page - Technical references and schematics archive: alarm, audio, auto, etc.

    The Electronic Peasant - Dedicated to inexpensive Do-It-Yourself music electronics, electronic salvage/recycling, and alternative energy projects.

    Electronics and Electrical Engineering Resource - Electronics theory, books, construction projects, tips, and practical advice.

    Electronics Circuit Forum - Electronic circuits and projects with description, diagrams and PCB, electronics articles.

    Electronics Circuit Search Engine - A search engine for electronics circuits.

    Electronics Guides and Projects - Contains electronics projects and guides, including microcontroller programming.

    Electronics Hobbyist - Projects for beginners, articles on electronics and electrical science, Tesla coils, electrostatic devices, and resource links for the hobbyist and educator.

    Electronics Infoline - Search engine and categorically organized circuits in a directory.

    Electronics Lab - Electronic circuits with full description, diagrams and PCB, electronics articles, links and downloads.

    Electronics Projects with Circuit Diagrams - A collection of electronics projects and circuit diagrams. How to build your own electronic gadgets.

    Electronics Zone - Electronic circuits, kits, do-it-yourself, circuit diagrams, design and electronics hobby schematics from alarms to test circuits.

    Electroniq.net - Electronic schematics, circuits, projects, tutorials and software for hobbyists.

    FC's Electronic Circuits - Circuits on solar power, micro power FM broadcasting, a temperature controlled NICD charger, and more from Forrest Cook; electronics links.

    Free Circuit Diagram - Electronic circuit schematic diagrams collection.

    Free Electronics Schematics Diagrams - Electronics diagrams: pro music equipment, vintage tube amplifiers and other; chat room.

    Hobby Circuits - A large collection of simple electronic circuits for hobbyists from Imagineering On-line Magazine.

    Hobby Electronics - From Japan. Several interesting circuits. Some interesting theory and applications.

    Home Brew Spectrum Analyzer - How to make a spectrum analyzer with tips and advice on component selection and architecture. A large number of circuit ideas and schematics, with sources and construction tips.

    Hotwater Electronics Projects - Electronic projects covering GPIB connectivity, instrumentation, microcontrollers, Ham radio and wireless communications with PCBs and key components.

    Julien Thomas Enterprises - RS-232 protection and connections schemes. For protecting your Mother Board.

    Learn Electronics - Schematics with descriptions and do-it-yourself electronic projects for hobbyists.

    Music Electronics µArchive - An archive of tube and transistor amplifiers and information, mostly for music applications.

    PIC Based Analog Synth - Project to build a real analog synthesizer using easy to get components.

    Ronald´s Electronic Project Site - Fully documented electronic projects, such as stand alone microcontroller circuits and nixie, numitron and decatron clocks.

    Rugby PIC Clock - Schematic a construction of a 60kHz time code receiver and clock. Includes PIC programmer and LED clock display.

    Sam Electronic Circuits - Electronic Circuits for the hobbyist, analog, audio and digital, useful circuits with full Greek descriptions , diagrams in Greek and English.

    Sam's Schematic Collection - Includes information about safety, power supplies, Jacobs Ladders, circuits, IR detectors, power oscillators, and schematics.

    Small TV Terminal - TV terminal design. Connects TV and PC keyboard to a microcontroller based device.

    StarGate-TR - Projects related to Electronics Engineering. Includes schematics, source codes of embedded systems, such as microcontroller based electrical motor driver or finite element analysis with free tools.

    Synthesizer Home Page - How to make a very nice and stable frequency synthesizer from Harvard. Includes schematics, block diagrams and parts lists. Very through design.

    Tech Tut - A blog on electronics projects, ideas, and tips on repairing broken electronics.

    Techlib.com Electronics - Audio, PC, games, phone, oscillator, power, test equipment, and weather related schematics and information.

    Television Schematics - Television schematics for electronic specialists who repair TV sets.

    Tomi Engdahl's Electronics Pages - Electronic circuits and projects designed by Tomi Engdahl. Audio, video, computer, data communication, light effects and controllers, power supplies, and telephone circuits.

    WeMan's Electro Stuff - Audio tubes, transistors, analog circuits, transistor amplifiers as well as connector pinouts.

    Your Electronics Open Source - Electronic projects, firmware, circuit board, reference designs, datasheet, application notes.


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