取款宝 - 最权威的电子平台

Diodes: Diodes are also called crystal diodes, or diodes for short. In addition, there are early vacuum electronic diodes; they are electronic devices with unidirectional conduction current. There is a PN junction and two lead terminals inside the semiconductor diode. This electronic device has the unidirectional current transmissibility according to the direction of the applied voltage. Generally speaking, a crystal diode is a p-n junction interface formed by sintering a p-type semiconductor and an n-type semiconductor. Space charge layers are 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 caused by the difference in the carrier concentration on both sides of the p-n junction is equal to the drift current caused by the self-built electric field, and it is in an electrical equilibrium state, which is also a diode characteristic under normal conditions. Semiconductor diodes are used in almost all electronic circuits. They play an important role in many circuits and their applications are also very extensive.



The color of SMD LEDs is red, yellow, green, blue, etc. There are three types of commonly used packages: 0805, 1206, and 1210.



According to the color of the light-emitting tube, it can be divided into red, orange, green (also subdivided into yellow-green, standard green and pure green), blue light, white light and so on. In addition, some light-emitting diodes include chips of two or three colors.



The light emitting diodes of the above various colors can be further classified into colored and transparent, colorless and transparent, colored scattering, and colorless scattering according to whether the light emitting diode is doped with or without a scattering agent, colored or colorless. Diffuse light-emitting diodes are used as indicator lights.