The difference between diode and resistor

Last Update Time: 2018-12-08 11:39:22


Diodes are generally made of semiconductor materials such as silicon, germanium, etc., which are made of some impurity elements and have unidirectional conductivity. The resistor can be bi-directional and belongs to the energy consuming component.

 

A diode is a device with two electrodes that allows current to flow in a single direction, many of which are applied to its rectification function. The varactor is used as an electronically tunable capacitor. The current directionality of most diodes is often referred to as the "rectifier" function. The most common function of a diode is to allow only current to pass in a single direction (called forward bias) and reverse direction (called reverse bias).

Therefore, the diode can be thought of as an electronic version of the check valve. An early vacuum electronic diode; it is an electronic device that conducts current in one direction. Inside the semiconductor diode, there is a PN junction and two lead terminals. The electronic device has a unidirectional current conductivity according to the direction of the applied voltage. Generally, a crystal diode is a p-n junction interface formed by sintering a p-type semiconductor and an n-type semiconductor. A space charge layer is formed on both sides of the interface to form a self-built electric field. When the applied voltage is equal to zero, the diffusion current is equal to the drift current caused by the self-built electric field due to the difference in the concentration of carriers on both sides of the p-n junction, and is in an electric equilibrium state, which is also a diode characteristic under normal conditions.

The resistor is a current-limiting component. After the resistor is connected to the circuit, the resistance of the resistor is fixed. Generally, it is two pins, which can limit the current through the branch connected to it. A resistor cannot be changed and is called a fixed resistor. A variable resistance is called a potentiometer or a variable resistor. The ideal resistor is linear, ie the instantaneous current through the resistor is proportional to the applied instantaneous voltage. Variable resistor for voltage division. On the exposed resistor body, one or two movable metal contacts are pressed. The contact position determines the resistance between either end of the resistor body and the contact. The resistance value of the resistance element is generally related to temperature, material, length, and cross-sectional area. The physical quantity that measures the magnitude of the resistance of the resistance is the temperature coefficient, which is defined as the percentage change of the resistance value for every 1 °C increase in temperature. The main physical characteristic of a resistor is that it converts electrical energy into thermal energy. It can also be said that it is an energy-consuming component through which current generates internal energy. The resistor usually functions as a partial pressure or a shunt in the circuit. For signals, both AC and DC signals can pass through the resistor.

 

This article is from ALLICDATA ELECTRONICS LIMITED.