Printed circuit boards only allow the transfer of current to the different components that are soldered on them. Still, the components that are on the circuit board are just as important. Without components, a gadget will certainly not be able to function, rendering the circuit board useless.
Think of it as analogous to a city. The printed circuit board is the city itself. There are services, buildings, and essential places that function within the city. These buildings and services need manpower to function. So, think of the buildings and services as the components. The current is represented by the people whose manpower enables the buildings and services to function. To get there, the people need roads and other forms of transportation. This is represented by the copper tracks that form an electronic circuit on the board. Each part plays an essential role for the city to function properly.
Moving on to the parts of printed circuit boards, electronic components are devices or micro devices within an electronic system that serve specific functions. There are usually two or more terminals within an electronic component. Terminals are the points of contact between the component and the electronic circuit. They are also where the flow of electricity ends. The terminals are usually metal rods that extend from an electric component. These rods are then soldered to the printed circuit board.
The electronic components of printed circuit boards are usually classified into two: active components and passive components. However, other materials are classified under a third type of electronic component called electromechanical.
Types of Electronic Components
Active components are those that need a source of energy to function, meaning electricity. Active components may also introduce power into the electronic circuit and may amplify power and electronic signals as well. Passive components, on the other hand, are those that cannot introduce energy into the electrical circuit and can only allow energy to “pass” through them. They can only draw power from the electronic circuit upon which they are connected. Passive components also cannot amplify signals and usually feature only two terminals – one for positive and one for negative. Lastly, electromechanical components are those that use parts and/or electrical connections to carry out functions.
The most common kinds of active components are semiconductors. Examples of these are transistors and integrated circuits. Transistors are commonly used in amplifying electronic signals. They can also be used to switch electronic signals. Transistors usually have three terminals wherein the current that is applied on one of the terminals changes the current that is applied on the other two. Integrated circuits are two or more sets of electronic circuits compressed on one small plate. These plates are usually chips or microchips like the central processing units found on today’s computers.
There are usually two designs of integrated circuits: analogue and digital. Analogue circuits are more into physical signals within semiconductor devices like power or resistance. They can be used to amplify and filter analogue signals like television signals or music. On the other hand, digital circuits are those that handle logical signals like whether signals are true or false, high or low, 0 or 1. Digital integrated circuits are designed to handle mathematical processes.
Passive and Electromechanical Components
Moving over to passive components, the most common types of these are capacitors and resistors. Capacitors are commonly used to store electrostatic energy. Meanwhile, resistors are electrical components that exhibit electrical resistance to the current within the circuit. Resistors are used mostly to reduce and lower the current flow inside the circuit. The last type of components found within printed circuit boards are the electromechanical components. A common example of an electromechanical device is a switch, which needs a moving part to either inhibit or restore the flow of electricity within an electronic circuit.