Introduction to Arduino Boards

Arduino

• It's an open-source electronics platform and microcontroller, complete with its own programming software/IDE.
• It is designed to be inexpensive, easy to use, and easy to learn.
• It is connectable to relays, motors, and sensors.

History

• Development began at the Interaction Design Institute Ivrea in Italy.
• It's based on Hernando Barragan's thesis, "Wiring: Prototyping Physical Interaction Design".
• Wiring's objective was to simplify electronics for artists and designers.
• Massimo Banzi produced the first prototype in 2005.
• He was later joined by David Cuartielles, Tom Igoe, Gianluca Martino, and David Mellis.

Arduino Boards

• Diecimila was released in 2007 using the ATmega168V microcontroller.
• LilyPad was released in 2007 using the ATmega168V/ATmega328V microcontroller.
• Nano was released in 2008 using the ATmega328/ATmega168 microcontroller.
• Mini was released in 2008 using the ATmega168 microcontroller.
• Mini Pro was released in 2008 using the ATmega328 microcontroller.
• Duemilanove was released in 2008 using the ATmega168/ATmega328 microcontroller.
• Mega was released in 2009 using the ATmega1280 microcontroller.
• Fio was released in 2010 using the ATmega328P microcontroller.
• Mega 2560 was released in 2010 using the ATmega2560 microcontroller.
• Uno was released in 2010 using the ATmega328P microcontroller.
• Ethernet was released in 2011 using the ATmega328 microcontroller.
• Mega ADK was released in 2011 using the ATmega2560 microcontroller.
• Leonardo was released in 2012 using the ATmega32U4 microcontroller.
• Esplora was released in 2012 using the ATmega32U4 microcontroller.
• Micro was released in 2012 using the ATmega32U4 microcontroller.
• Yún was released in 2013 using the ATmega32U4+ Linino microcontroller.
• Zero was released in 2015 using the ATSAMD21G18A microcontroller.

Arduino UNO R3

• It is basic and inexpensive.
• It is the most popular Arduino board.
• It has a market share of over 50%.
• It is the best prototyping board for beginners in electronics and coding.

LilyPad Arduino

• It is used in e-textiles and wearable projects.
• It can be sewn to fabric.
• Power supplies, sensors, and actuators can be mounted similarly.

Arduino Nano

• Functionally like the UNO, but with different components and layout.
• Lacks a DC power jack.
• Has a compact size.

Arduino Esplora

• The Esplora allows users more direct control over their creations.
• This board is used more as a user interface for other electronic projects.

Power (USB / Barrel Jack)

• Arduino can be powered via:
  • A USB connection.
  • A DC power source via the jack.

Pins

• GND: Ground pins for grounding a circuit.
• 5V & 3.3V: Supplies power with 5 or 3.3 volts.
• Analog: Reads signals from analog sensors (e.g., temperature sensor).
• Digital: Used for both digital input and output.
• PWM: Pulse-Width Modulation pins act as normal digital pins.
• AREF: Analog Reference pin that can be used to set an external reference voltage (between 0 and 5 Volts) for the analog input pins.

Reset Button

• Connects the reset pin to ground.
• Restarts any loaded code.

Power LED Indicator

• A small LED next to 'ON' lights up when the Arduino is plugged into a power source.

TX RX LEDs

• TX (transmit) and RX (receive) LEDs provide visual indications when the Arduino is sending/receiving data.

Main IC

• It is the "brain" of the Arduino.
• The IC type may be required to load programs from the Arduino software.

Voltage Regulator

• Controls the amount of voltage let into the Arduino board to prevent damage for voltages normally greater than 20 volts.

Arduino IDE

• It programs an environment for drafting different kinds of programs, and then loading programs into the Arduino Microcontroller.
• It uses a user-friendly programming language based on processing.
• The IDE compiles and translates to the assembler language.
• It then uploads the program to the Arduino microcontroller.
• The built-in code parser checks the user written code before sending it to the Arduino.

Embedded System

• A combination of computer hardware, software, and additional mechanical or electronic parts designed to perform a dedicated function.
• It is an applied computer system built to control a range of functions.
• Advancing technology causes decrease in the cost of manufacturing and allows implementation of various hardware and software components.

Resistors

• A passive two-terminal electrical component that implements electrical resistance as a circuit element.

Brief History on Resistors

• Georg Ohm was a German physicist and mathematician.
• He was known for his “Ohm’s Law”.
• Ohm’s Law states that the current through a conductor between two points is directly proportional to the voltage across the two points.
• The resistor was invented by Otis Frank Boykin in 1959.
• He invented a control unit for the artificial cardiac pacemaker.
• He died because of heart failure in 1982.

Capacitors

• An electronic component that stores electric charge.
• Made of two close conductors (usually plates) separated by a dielectric material.
• Plates accumulate electric charge when connected to a power source; one plate accumulates positive charge and the other plate accumulates negative charge.
• Capacitors are measured in Farads.

Transistors

• A three leg component.
• In a computer they're in millions of numbers in small microchips.

Brief History About Transistors

• Before transistors, first generation computers used vacuum tubes for logic circuitry.
• The first general-purpose electronic computer, ENIAC, had more than seventeen thousand vacuum tubes.
• Vacuum tube cathodes are needed to be heated first to work.
• Vacuum tubes burnt out regularly and needed to be replaced.
• Because of the large number of vacuum tubes, the ENIAC was very power hungry.
• The first transistors were developed by John Bardeen, Walter Brattain, and William Shockley at AT&T Bell Laboratories in the mid 1940s.

Integrated Circuits

• It is a small chip that can function as an amplifier, oscillator, timer, microprocessor, or even computer memory.

Types of IC’s

• Digital Integrated Circuits
• Analog Integrated Circuits
• Mixed Integrated Circuits
• Logic Circuits
• Comparators
• Switching ICs
• Audio amplifiers
• Operational amplifiers

Potentiometers

• A manually adjustable, variable resistor with three terminals.
• Two Terminals are connected to a resistive element.
• The third terminal is connected to an adjustable wiper.
• The position of the wiper determines the output voltage.

Different types of Potentiometers

• Rotary potentiometers:
  • The most common type of potentiometer.
  • Where the wiper moves along a circular path.
• Linear potentiometers:
• Potentiometers where the wiper moves along a linear path.
• Also known as slider, slide pot or fader.

Diodes

• A two-terminal electrical device that allows the transfer of current in only one direction.
• Used for rectifying waveforms, within radio detectors, or within power supplies.
• Used in various electrical and electronic circuits where ‘one-way’ result of the diode is required.
• Most of diodes are made from semiconductors like Si (silicon), but sometimes, Ge (germanium) is also used.

Brief History About Diodes

• The story of invention revolves around the perseverance of Russel S. Ohl who discovered the basic form of PN Junction.
• Russel Ohl was a researcher with AT &T Bell laboratories who specialized in materials research.

Types of Diodes

• Diode: Allows current flow in one direction only (left to right).
• Zener Diode: Allows current flow in one direction, but also can flow in the reverse direction when above breakdown voltage.
• Schottky Diode: A diode with low voltage drop.
• Varactor / Varicap Diode: Variable capacitance diode.
• Tunnel Diode
• Light Emitting Diode (LED): Emits light when current flows through.
• Photodiode: Allows current flow when exposed to light.

Light-Emitting Diode (LED)

• An LED is a small component that gives light.
• It is similar to a standard diode, but with Electroluminescence.

Types of LED

• The LED has two pins called anode and cathode. -The anode is the longest pin, and is connected to the most positive voltage. -The cathode is the pin you connect to the most negative voltage. -They must be connected correctly for the LED to work.

Light Dependent Resistors (LDR)

• An LDR has a variable resistance that changes with the light intensity that falls upon it.
• This allows them to be used in light sensing circuits.
• Are sensitive devices.
• Used to indicate the presence or absence of light, or to measure the light intensity.

Some Applications of LDRs

• Lighting switch: Automatically turn on a light at a certain light level.
• Camera shutter control: Controls the shutter speed on a camera to measure the light intensity.

Button Switch

• A simple switch mechanism for controlling some aspect of a machine or a process.
• Buttons are typically made out of hard material, usually plastic or metal.
• The surface is usually flat or shaped to accommodate the human finger or hand, so as to be easily depressed or pushed.
• Buttons are most often biased switches.

Relays

• Switches that open and close circuits electromagnetically or electronically.

Some Types of Relays

• Contactor: A type of relay that can handle the high power required to directly control an electric motor or other loads.
• Solid-state relays: Control power circuits with no moving parts, instead using a semiconductor device to perform switching.
• Magnetic latching relays: Require one pulse of coil power to move their contacts in one direction, and another, redirected pulse to move them back.

Multimeters

• It is known as a volt-ohm meter.
• It is a handheld tester used to measure electrical voltage, current(amperage), resistance, and other values.

Types of Multimeters

• Analog multimeters use a microammeter with a moving pointer to display readings.
• Digital multimeters (DMM, DVOM) have a numeric display, and may also show a graphical bar representing the measured value.