Analysis of eight common components

In our life, we see most of the  circuit boards have the components. And there are different components on the circuit board.They have different shapes, different colors, different legs of them and so on. They also provide different functions, so today we will introduce 8 kinds of circuit board components , that we commonly use,  and we also will learn about their functions.

First, let us see a picture, this is a circuit boards with several kinds of the components. We can see resistors, capacitors, connectors and so on.


First, let us learn about the resistor.

1.What is a resistor: Elements with a certain resistance made of conductors

2.The role of resistors:The main function is to hinder the flow of current, and we use it in current limiting, shunt, step-down, voltage divider, load and capacitor cooperation, filter and resistance matching, etc.

3.Common sense of resistor selection:

①Selection of resistance value: The principle is that the smaller difference between the nominal value of the resistor used, and the resistance value of the required resistor, it is better.

②Rated voltage: When the actual voltage exceeds the rated voltage, even if they meet the power requirements , it will damag the resistor  by breakdown.

③Rated power: The rated power of the selected resistor, that should be more than twice the actual withstand power, it can ensure the reliability of the long-term operation of the resistor in the circuit.

4.Here are some Resistor’s pictures


  1. Concept:It consists of two metal electrodes, and sandwiching a layer of insulating medium. When we apply the voltage between the two electrodes, it will store the charge on the electrodes.
  2. The role of capacitors:Tuning, filtering, coupling, DC blocking, AC bypassing and energy conversion.
  3. Here are some Capacitor’s pictures


1.What is an inductor:Components that can produce inductance, they are collectively referred to as inductive components.

2.Effect:Block AC and pass DC, block high frequency and pass low frequency (filtering).

3.Inductors are energy storage components, and on the circuit board the devices used for energy conversion, or in other words, the components used for energy consumption are called magnetic beads.

4.For example


1.Concept:Semiconductor diode, also known as crystal diode, referred to as diode, consists of a PN junction plus lead and tube shell. It has unidirectional conductivity and is a nonlinear component.

2.Function: detection, rectification, switching, voltage regulation, etc.

3.Diode positive electrode and negative electrode judgment method:

negative electrode:

①colored ring



②Mark the side of the arrow



③Side with short legs





4.Pictures of Diode


1.Concept: Semiconductor triode, also known as bipolar transistor, transistor triode, referred to as triode, is a semiconductor device that controls current.

2.Function: Amplify the weak signal into a larger electrical signal, as well as a non-contact switch .


Switch Element

1.Concept: It is a component that can turn on and off a circuit board. We can see switches  in various electronic devices and household appliances.


Integrated Circuit

When it comes to integrated circuits, you may not have heard of them, but you must have heard of another name for him: chips or IC.

1.Concept:The integrated circuit is a device obtained by making multiple components, and connecting wires on the same semiconductor substrate , that using a semiconductor manufacturing process , in other words, we usually call it an IC-integrated circuit.。

2.Features: small size, low power consumption, high reliability, low cost, etc..

3.Common packages:SIP, DIP, SOP, SSOP, PLCC, BGA, QFN

4.How to confirm chip polarity:

①a corner with a dot

②there is a gap in the corner

③a corner with numbers

5.Here are some images of IC


  1. Concept: A device that connects two components on a circuit board to transmit current or signals.
  2. Function: Set up a bridge of communication between the blocked or isolated circuits in the circuit, so that the current can flow and the circuit board can achieve the predetermined function.
  3. Connector Benefits:

①Improve production process:The connector simplifies the configuration process of electronic products,  and it builds a bridge of communication, so that the current flows and the circuit achieves the predetermined function

②easy to repair:If an electronic component fails, the failed component can be quickly replaced when the connector is installed

③Easy to upgrade:As technology advances, when we install the connectors, if we want to update the components , we just can replacing old ones with new, more complete components.

④Increase design flexibility:Using connectors gives engineers greater flexibility when designing and integrating new products, as well as when building systems from components.

The above is the relevant analysis of the eight major components, which we often see on the circuit board.

In fact, there are many components on the circuit board, such as: voltage controller, fuse wire, crystal , electroacoustic devices, etc..

If you have any questions, please leave us a message to communicate.