Electronics components basics 2020
In this post, you will read about the fundamentals of electronics. At the end of this post, you will able to
explain the basics concepts of electronics,
identify electronic components
explain the fundamentals of electricity.
Introduction to Electronics
Electronics is the branch of science it involves the study of flow. This branch deals with electrical circuits involving active electronic components such as transistors, diodes, and integrated circuits and passive
electronic components such as resistors, capacitors, and inductors, along with interconnection technologies.
The following figure shows some concepts that form the basis of electronics:
Components and Devices
- Analog Circuit
- Digital Circuit
- Basic Circuit
- Ohm’s Law
- Kirchoff’s Law
- Alternating current(AC)
- Direct Current(DC)
Measuring Instrument Equipment
- Digital multimeter
- Clamp meter
- Power supplies
- Voltage Source
- Current Source
All the circuits of a computer are made up of various basic electronic components. These components are the fundamental building blocks of the electrical/ electronic circuits. They are generally found on the hard disk drive, motherboard and on the other parts of a computer and its peripherals. For a field technician, it is necessary to identify these components correctly.
The electronic components are embedded on printed circuit boards(PCBs). A PCB acts as a base for the components that are mounted on its surface and soldered. The circuits are initially built and it tested on a breadboard before being embedded on a PCB. The following image shows a motherboard PCB and a few electronic components embedded on it:
Electronic components that may be embedded on a PCB are of two types:
These components depend on a source of energy to perform their functions. They can amplify current and produce a power gain. The following figure represents a list of active components:
A diode is a specialized electronic component with two terminals known as the anode and the cathode. It has asymmetric conductance, which means that it conductance, which means that it conducts mainly in one direction . It has very little resistance(ideally Zero), to the flow of current in one direction. It has high resistance(ideally infinite), in the other direction. Diodes are usually made up of semiconductor materials such as germanium, silicon or selenium. The following image shows diodes:
A transistor is an electronic device, made up of semiconductor material. Usually, it has at least three terminals to connect to an external circuit. It is used to amplify or Switch electrical power and electronic signals. The following image shows a transistor:
An IC, also known as a microchip, is a semiconductor wafer on which a number of small resistors, capacitors and transistors are fabricated. It can work as an oscillator, an amplifier, a timer, a counter, a microprocessor or as a computer memory. The following image shows an IC:
Light Emitting Diode(LED)
It is a p-n junction diode that gives out light when it is activated. It is a two-lead semiconductor source of light. Energy is released as photons when a suitable voltage is applied to the leads. The following image shows an LED:
A power source is a source that provides powers to a circuit. Generally, it is a generator or a battery.
The following image shows a battery:
These components do not require any power source to perform their specific functions. They are not capable of controlling the current. The following figure lists different passive components in a circuit:
A transformer consists of a metal core with coils of wire around it. It is a device used to convert AC to the required values by decreasing or increasing the alternating voltages in an electronic or electric system.
The following image shows a transformer:
A resistor is a component in an electronic circuit that is built to resist or limit the flow of current in that circuit. It may be a small carbon device or a big wire-wound power resistor. Its size varies in length from 5mm up to 300mm. The following image shows different types of resistors:
A capacitor is a device that is made up of one or more pairs of conductors and an insulator separating them. It is used to store an electric charge. The following image shows capacitors:
Fundamentals of electricity
Electricity is a natural force that comes into existence whenever there is a flow of electric charge between any two components . The flow of electric charge is called current . Voltage is potential difference between negative and positive charged components. When working with circuits, basic knowledge of electricity is very important to ensure that all connections are correct. A wrong connection in a circuit may cause high damage to people and the circuit components.
Introduction to PCB
In personal computers, a motherboard is the PCB that provides connectors for peripherals and has many important components on the board.
It is the main circuit board of a computer. A motherboard includes the following devices:
- I/O ports
- ROM chip
- Expansion slots
- Peripheral controllers
Motherboard is also known as “Mainboard” or “System Board”.
Types of PCB
There are two types of motherboards:
- Non-integrated PCB(older): peripheral controllers were not on the motherboard. Additional boards (called add-on-cards) were installed in expansion slots as per requirement. For example, a video card, floppy disk drive(FDD) controller card, hard disk drive(HDD) controller card, serial and parallel port card and sound card.
- Integrated PCB(latest): Most of the peripheral controller cards are integrated on the motherboard itself. Electronics of these logics are integrated in the motherboard and connectors are visible on the rear panel of the PC.
Chipset: A chipset is a motherboard component that includes the CPU and other chips that support basic functions of the computer.
The two main chips in the chipset are:
Northbridge: Northbridge is the part of the computer chipset that provides a network between the CPU and the other interfaces of the computer. These interfaces may include memory, Accelerated graphics port(APG) port and peripheral component interconnect (PCI) bus. It is also linked to the southbridge.
Southbridge is the portion of the computer chipset that provides a network between the northbridge and the slower speed interfaces and then further connects the interfaces to the
CPU. These interfaces may include parallel ports, serial ports, Universal Serial Bus (USB) ports and PS/2 ports. The southbridge controls the slower I/O components like the Serial ports, USB ports and the integrated development environment (IDE).
The form factor of the motherboard determines the physical organization, general shape, the sorts of cases and power supply usage of PCB. It also specifies the physical layout, order of the board and the arrangement of mounting holes in the PCB. For example, a company can manufacture two motherboards with the same functionality but having a different form factor. The real differences lie in the physical layout and the position of the components on the board.
PCB has many components embedded in it. The two main components are:
A processor is a logical circuitry unit embedded in a PCB (or motherboard), which helps in running the system software such as OS and other applications such as window office. It also executes instructions given by the user. It is also known as CPU and contains a silicon chip. It can perform complex calculations. There are different types of processors such as advanced micro devices (AMD), digital signal processors (DSP) and Intel processors.
A processor contains three basic components:
• I/O unit
- Control unit (CU).
- Arithmetic logic unit(ALU)
The components of a processor are discussed in the following figure:
Processor Frequency or Speed
The speed of the processor at which it operates internally is known as processor frequency For example, the processor’s internal operating speed is 3.2 GHz but external operating speed is 800 MHz. In this case, 3.2 GHz is the frequency of the processor and 800 MHz is the frequency of the system bus.
Processor technologies can be used by AMD only, by Intel only or by both the vendors. These technologies help in distinguishing in between different processors in terms of their performance or features, The processor technologies can be classified as:
- Over clocking
- Voltage regulator module (VRM)
- Hyperthreading (HT Technology)
The default frequencies of motherboard and processors can be altered just by changing a BIOS set-up setting. Overclocking is the process in which a motherboard or processor works at a higher speed or velocity than that recommended by the manufacturer. The stability of the speed is not guaranteed in running the motherboard or processor in overclocking. Hence, it is inadvisable to run the motherboard or processor in it. In addition, much higher speed or velocity can create overheating, which can damage the processor. So, the major area of concern to deal with while overclocking a system is overheating.
A CPU is a collection of transistors. These transistors work at a specific voltage level. If excessive voltage is supplied to the transistor, it will burn off. Hence the motherboard manufacturers have to take special care of the CPU voltages.
Throttling is a process that is responsible for maintaining the rate at which the processing of an application is conducted. Whenever the system is overheated, it lowers down the frequency it also helps in conserving power. It is also known as dynamic frequency scaling.
Intel developed a technology known as HT Technology. Two execution threads are processed by the HT technology inside a processor. On enabling it in the BIOS of the system, the single processor appears as two processors to the operating system.
In the architecture of a computer , a bus works as a communication system that transmits data amidst various computers or components within a computer . A computer is comprised of many components such as the CPU, I/O devices and the memory chips. A bus is a common passage or a group of wires that interconnects all these subsystem of a computer. Thus , the different components are able to exchange information through the bus.
Based on the flow of data between different devices, buses are classified as follows:
Types of buses
There are four types of buses connecting different devices as shown in the following figure:
- System bus refers to the bus which connects the CPU with the system memory.
- The system bus is the main communication path between the CPU and memory.
- The address bus is necessary to provide the address of the location where the data can be stored or retrieved.
- Data bus is bidirectional and the data is transferred to and from the CPU.
- The control bus is used to coordinate the data between the CPU and the peripherals devices or memory.
The following image shows the connection of different buses with the devices: