Three major electronic components
In the electronics industry, all kinds of electronic components have their own important uses. For people in the electronics industry, electronic components are the same as the water they drink every day. They are exposed every day, but there are many little knowledge in it. learn. Here are three commonly used electronic components in the electronics industry, as well as related basic concepts and knowledge, and review them with everyone.
As a worker in the electronics industry, resistance is unknown to everyone. Its importance is beyond doubt. Resistance is very much used in the electronics industry, and the obstacle that substances produce to current is called resistance. Resistance will change the flow of electrons, the smaller the resistance, the greater the flow, and vice versa. A substance with no resistance or very low resistance is called a conductor. Substances that cannot form current transmission are called insulators.
In physics, resistance represents the size of the conductor's obstructive effect on current. The greater the resistance of the conductor, the greater the resistance of the conductor to the current. Different conductors generally have different resistances, and resistance is a characteristic of the conductor itself. The resistance element is an energy dissipating element that hinders the current.
The resistance value of a resistance element is generally related to temperature. The physical quantity that measures the magnitude of resistance affected by temperature is the temperature coefficient, which is defined as the percentage of the resistance value that changes when the temperature rises by 1°C.
Resistance is represented by "R" plus a number in the circuit. The main function of resistance in the circuit is shunting, current limiting, voltage division, biasing, etc.
Parameter identification: The unit of resistance is ohm, and the multiplying unit is: kiloohm, megaohm, etc. The conversion method is: 1 megohm = 1,000 kiloohms = 1,000,000 ohms
Capacitance is the amount of charge storage; it is denoted as C, and the international unit is farad. Generally speaking, electric charges move under force in a power plant. When there is a medium between the conductors, the movement of electric charges is hindered and the electric charges accumulate on the conductors; this causes the accumulation and storage of electric charges. A common example is two parallel metal plates. . It is also a common name for capacitors.
1. Capacitors are generally represented by "C" plus a number in the circuit. A capacitor is a component composed of two metal films close together and separated by an insulating material. The characteristic of the capacitor is mainly to block the direct current and pass the alternating current. The size of the capacitance indicates the amount of electric energy that can be stored. The obstructive effect of the capacitance on the AC signal is called capacitive reactance, which is related to the frequency and capacitance of the AC signal.
2. Identification method: The identification method of capacitance is basically the same as that of resistance, which can be divided into three types: direct marking method, color marking method and number marking method. The basic unit of capacitance is expressed by Farah, and other units are: millifarad, microfarad, nanofarad, and picofarad. Among them: 1 farad=103 millifarads=106 microfarads=109 nanofarads=1012 picofarads, the capacitance value of a large capacity capacitor is directly marked on the capacitor, and the capacitance error table symbol FGJKLM allows the error ±1% ±2% ±5 % ±10% ±15% ±20%
Inductance: When the coil passes current, a magnetic field is induced in the coil, and the induced magnetic field generates an induced current to resist the current passing through the coil. We call this interaction between the current and the coil the electrical inductance, which is the inductance, and the unit is "Henry" (H).
Inductance is often represented by "L" plus a number in the circuit. The inductance coil is made by winding an insulated wire around a certain number of turns on an insulated frame. DC can pass through the coil. The DC resistance is the resistance of the wire itself, and the voltage drop is very small; when an AC signal passes through the coil, self-induced electromotive force will be generated at both ends of the coil. The direction of the self-induced electromotive force is opposite to the direction of the applied voltage, which hinders AC Pass, so the characteristic of the inductance is to pass DC and resist AC, the higher the frequency, the greater the coil impedance. Inductance and capacitance can form an oscillating circuit in a circuit. Inductance generally has direct calibration method and color calibration method, and the color calibration method is similar to resistance.
The basic unit of inductance is: Hen (H) The conversion unit is: 1H=103mH=106uH.