Electronics Reviewer PDF

ELECTRONICS REVIEWER (baste version) Electricity is generated when electrons shift between atoms, producing energy. It’s a natural phenomenon linked to the movement of electric charge and is essential for the operation of electrical and electronic devices. The fo...

ELECTRONICS REVIEWER (baste version) Electricity is generated when electrons shift between atoms, producing energy. It’s a natural phenomenon linked to the movement of electric charge and is essential for the operation of electrical and electronic devices. The four key properties of electricity are current, voltage, resistance, and power. Georg Simon Ohm created Ohm’s Law, which calculates the relationship between voltage, current, and resistance in an electrical current. Current (Amperes/A): The flow of electrons, like a river. 0.5 amperes can cause a shock. André-Marie Ampère, a French physicist, proposed the existence of electrons and created a magnetic field using electric current. Voltage (Volts/V): The force driving electrons, similar to the steepness of land. Alessandro Volta, an Italian physicist, made the first battery and showed that electrical current is generated by contact between different metals. Resistance (Ohms/Ω): The force that opposes or slows the flow of current, like debris or a dam. Georg Simon Ohm described the relationship between current, resistance, and voltage. Charge (Coulombs/q or Q): The amount of charge passing through a conductor carrying one ampere per second. Charles-Augustin de Coulomb formulated Coulomb’s Law, stating that electrostatic force is proportional to the product of the charges and inversely proportional to the distance between them. Power (Watts/W): The rate of doing work. James Watt was a Scottish inventor known for his steam engines. Electrons (e-) are negatively charged subatomic particles that generate electrical energy. Units: Kilo (k) = 1,000 Mega (M) = 1,000,000 Milli (m) = 1/1,000 Micro (µ) = 1/1,000,000 Nano (n) = 1/1,000,000,000 Pico (p) = 1/1,000,000,000,000 Electrical Circuits consume large amounts of power and include components like resistors, inductors, and capacitors, converting electricity into heat, light, etc. Electronic Circuits use semi-conductive materials, consume less power, and are used for processing, storing, and retrieving information. Examples include transistors. Types of Current Alternating Current (AC): Involves oscillation, with electrons moving forward and backward. It is used in power supplies like outlets and transformers. Direct Current (DC): Moves in only one direction, making it small and portable. It is commonly used in battery-powered devices. Passive and Active Electrical/Electronic Components: Active Components: Basis: Deliver power or energy to the circuit. Examples: Diodes, Transistors, SCRs, Integrated Circuits. Function: Produce energy in the form of voltage or current.  Power Gain: Capable of providing power gain. Flow of Current: Can control the flow of current. Nature of Energy: Energy donors. Passive Components: Basis: Utilize power or energy within the circuit. Examples: Resistors, Capacitors, Inductors. Function: Store energy in the form of voltage or current. Power Gain: Incapable of providing power gain. Flow of Current: Cannot control the flow of current. Nature of Energy: Energy acceptors. Circuit Diagram: Represents circuits using realistic images of components, providing a detailed and accurate portrayal of the actual components and their layout. Schematic Diagram: Uses standardized symbols to represent the elements and parts of a system. It employs abstract symbols to simplify and convey the functionality and connections within the circuit. Electrical and Electronic Components Analogy: Operating systems function like the nervous system, while components are similar to organs in bodily systems. A failure in a component can affect the entire system, leading to malfunctions or complete failure. 4 Important Components: Transistors: Control current flow and amplify signals. Resistors: Limit current flow and adjust voltage. Inductors: Store energy in a magnetic field and resist changes in current. Capacitors: Store energy in an electric field and smooth out voltage fluctuations. Breadboard: Used for prototyping circuits. Each hole is lined with conductive material to connect components. Connecting Wires: Insulated to allow current to travel between circuit points. Common materials include copper, gold, silver, tungsten, and aluminum. Conductibility (ability to allow current flow) ranks as follows: Silver (most conductive) Gold Copper (more used due to cost, availability, and similar conductivity to gold and silver) Power Supply: Provides electric power to a load by converting electric current to the correct voltage, current, and frequency. Common power supplies include cells, batteries, voltage outlets, and transformers. Additional components: Ground/Earth: Essential connection to the earth for safety and stability. Fuse: Prevents overload by breaking the circuit if the current is too high. Transformer: Adjusts voltage levels as needed. Examples include: DC Power Supply: Typically in the 0-12 volts range, with a maximum of 12.0 volts. LEDs: Typically operate at around 5 volts. Transducers (Output Devices): Convert energy from one form to another. Electrical Motor: Converts electrical energy to mechanical energy. Lights (LED, Fluorescent, Incandescent): Convert electrical energy to light energy. Speaker & Buzzer: Convert electrical energy to sound energy. Switches: Control the flow of current by connecting or disconnecting the conducting path. Push to Break: Used for digital timers and alarms. Push to Make: Used for buzzers. Single-Pole, Single Throw: Controls a device from one location (e.g., a light switch). Single Pole, Double Throw: A 2-way switch directing current to one of two routes. Double Pole, Single Throw: A dual on-off switch used for mains electricity. Resistors: Passive components that implement electrical resistance. There are two types: Fixed Resistor: Has a fixed value of resistance and is not adjustable. Examples include Carbon Composition Resistor, Wire Wound Resistor, and Chip Resistor (SMD). Variable Resistor: Can change the resistance value within a range. Carbon Composition Resistor: Made from a blend of carbon particles, graphite, and ceramic dust, mixed with a binder, and treated with high temperature and pressure. Resistor Color Code: 1st Band: 1st digit of the resistance value 2nd Band: 2nd digit of the resistance value 3rd Band: Multiplier (number of zeros) 4th Band: Tolerance value Tolerance Value indicates the accuracy of the resistance: 1. Gold: ±10% 2. Silver: ±5% 3. Red: ±2% 4. Brown: ±1% Wire Wound Resistor: Made by winding a resistive wire around a non-conductive core. The core provides mechanical support while the resistive wire conducts with resistance. Chip Resistor (SMD): Rectangular in shape with metallized areas at either end, allowing them to be mounted onto printed circuit boards using pads for electrical connection. Variable Resistor: Allows for the adjustment of resistance to control the flow of current. Example: Potentiometer. Capacitors: Two-terminal components consisting of two metal plates separated by an insulating material (dielectric). They are fundamental passive components, alongside resistors and inductors. Examples are: Capacitors - dielectric on the left | Ceramic capacitors on the right Transistors: Devices that control the movement of electrons and electricity, similar to a water faucet. They can start and stop current flow (switch) and control its amount (amplifier). Example: Traffic lights. Types of Transistors: Bipolar Junction Transistors (BJT): Invented by William Shockley and John Bardeen. Bidirectional devices using both electrons and holes as charge carriers. NPN Transistor: One p-type semiconductor between two n-type semiconductors. PNP Transistor: One n-type semiconductor between two p-type semiconductors. Field Effect Transistors (FETs): Consist of a channel of N- or P-type semiconductor material with a control mechanism (gate) that regulates current flow. Source: One end of the channel. Drain: The other end of the channel. Gate: Controls the flow of current from source to drain. Meters: Ammeter: Measures electric current. Voltmeter: Measures voltage (potential difference). Ohmmeter: Measures resistance. Galvanometer: Measures small amounts of current.