When it comes to electronics, there are numerous components that are essential to building any functional circuit. Here are 10 common electronic components that you’re likely to encounter.
Resistor will cause a change in the flow of electrons. The smaller the resistance, the greater the flow of electrons, and vice versa. Substances with no resistance or very little resistance are called electrical conductors, or conductors for short. Substances that cannot form electric current transmission are called electrical insulators, or insulators for short.
In physics, resistance is used to represent the size of the conductor’s resistance to current flow. The greater the resistance of the conductor, the greater the resistance of the conductor to current flow. Different conductors generally have different resistances, and resistance is a characteristic of the conductor itself. Resistive elements are energy-dissipating elements that impede current flow.
Resistor symbol: Resistor is represented by “R” plus numbers in the circuit, such as: R1 represents the resistance numbered 1. The main functions of resistors in the circuit are shunting, current limiting, voltage dividing, biasing, etc.
Capacitance refers to the charge storage capacity under a given potential difference; denoted as C, and the international unit is farad (F). Generally speaking, charges will move under force in an electric field. When there is a medium between conductors, it will hinder the movement of charges and make charges accumulate on the conductors; the accumulation and storage of charges is caused. The most common example is two parallel metal plates. It is also commonly known as a capacitor.
Capacitor symbol: Capacitor is generally represented by “C” plus numbers in the circuit (for example, C13 represents the capacitance numbered 13).
Inductance is a property of a closed circuit and a physical quantity. When the coil passes current, a magnetic field induction is formed in the coil, and the induced magnetic field will generate an induced current to resist the current passing through the coil. Inductors are inductive components made of inductive properties.
If the inductor is in a state where no current is flowing, it will try to block the current from flowing through it when the circuit is on; if the inductor is in a state where current is passing, it will try to maintain the current when the circuit is off. Inductors are also called chokes, reactors, and dynamic reactors.
Inductor symbol: Inductor is often represented by “L” plus numbers in the circuit, such as: L6 represents the Inductor numbered 6.
A crystal diode is a semiconductor two-terminal device in solid-state electronic devices. The main feature of these devices is their nonlinear current-voltage characteristics.
Since then, with the development of semiconductor materials and process technology, a variety of crystal diodes with various structures and functions have been developed using different semiconductor materials, doping distributions, and geometric structures. Manufacturing materials include germanium, silicon and compound semiconductors. Crystal diodes can be used to generate, control, receive, transform, amplify signals, and perform energy conversion.
Crystal diode symbol: Crystal diodes are often represented by “D” plus numbers in circuits, such as: D5 represents a diode numbered 5.
Zener diode is a semiconductor device with high resistance until the critical reverse breakdown voltage.
The Zener diode is a diode that uses the reverse breakdown state of the pn junction, and its current can change in a wide range while the voltage is basically unchanged. It is a diode that acts as a voltage regulator. The diode is a semiconductor device with high resistance up to a critical reverse breakdown voltage.
At this critical breakdown point, the reverse resistance decreases to a very small value, and the current increases while the voltage remains constant in this low-resistance region. Zener diodes are graded according to their breakdown voltage. Because of this characteristic, Zener diodes are mainly used as voltage regulators or voltage reference components. Zener diodes can be connected in series for use at higher voltages, and higher stable voltages can be obtained through series connection.
Zener diode symbol: Zener diodes are often represented by “ZD” plus numbers in the circuit, such as: ZD5 means a Zener diode numbered 5.
Varactor diodes, also known as ‘variable reactance diodes’, are made by utilizing the characteristics that the junction capacitance changes with the applied voltage when the pN junction is reverse-biased. It is used as a variable capacitor in high-frequency tuning, communication and other circuits. It is used in high-frequency circuits for automatic tuning, frequency modulation, tuning, etc., for example, as a variable capacitor in the tuning circuit of a TV receiver.
Varactor diode symbol: The text symbol of a varactor diode is exactly the same as that of an ordinary crystal diode, and is often represented by “VD” or “V”. If there are many similar components in the circuit diagram, numbers can be added after the text symbols to show the difference, such as VD1, VD, etc.
A transistor is a semiconductor device that controls current and can amplify current. Its function is to amplify weak signals into electrical signals with larger amplitude values. It is also used as a non-contact switch to control various electronic circuits.
The transistor is made on a semiconductor substrate with two PN junctions that are very close to each other. The two PN junctions divide the positive semiconductor into three parts. The middle part is the base area, and the two sides are the emitter area and the collector area. There are two types of arrangement, PNP and NPN.
Transistor symbol: The transistor is often represented by “Q” plus numbers in the circuit, such as: Q17 means the transistor numbered 17.
Field Effect Transistor
Field Effect Transistor is abbreviated FET. There are two main types: junction FET (JFET) and metal-oxide semiconductor FET (MOS-FET). Participated in conduction by majority carriers, it is also known as unipolar transistors. It is a voltage-controlled semiconductor device. With the advantages of high input resistance (108~109Ω), low noise, low power consumption, large dynamic range, easy integration, no secondary breakdown phenomenon, and wide safe working area, it has become a strong contender for bipolar and power transistors.
Field effect transistors can be used for amplification, variable resistors, constant current sources, electronic switches, and high input impedance, which are very suitable for impedance transformation.
Field effect transistors symbol: This symbol is often used in circuits to indicate field effect transistors.
A sensor is a physical device that can detect and sense external signals, physical conditions (such as light, heat, humidity) or chemical composition (such as smoke), and transmit the detected information to other devices.
The national standard GB7665-87 defines a sensor as: “A device that can sense a specified measured object and convert it into a usable signal according to a certain law (mathematical function rule), usually consisting of a sensitive element and a conversion element.”
Transformer is a device that uses the principle of electromagnetic induction to change AC voltage. The main components are primary coil, secondary coil and iron core (magnetic core). In electrical equipment and wireless circuits, it is often used for raising and lowering voltage, matching impedance, safety isolation, etc.
In a generator, whether the coil moves through the magnetic field or the magnetic field moves through the fixed coil, an electric potential can be induced in the coil. In both cases, the value of the magnetic flux remains the same, but the amount of magnetic flux intersecting the coil is different. This is the principle of electromagnetic mutual induction. A transformer is a device that uses electromagnetic mutual induction to transform voltage, current and impedance.
The functions of the transformer mainly include: voltage conversion; current conversion, impedance conversion; isolation; voltage stabilization (magnetic saturation transformer), etc.
Resistor is a passive two terminals electrical component used for limiting or regulating the flow of electricity in a circuit.
A capacitor is a device that stores electrical energy in an electric field by virtue of accumulating electric charges on two close surfaces insulated from each other. It is a passive electronic component with two terminals.
An inductor, also called a coil, choke, or reactor, is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it. An inductor typically consists of an insulated wire wound into a coil.