SMD LED is the surface mount light emitting diode. It is a solid state semiconductor device that converts electricity directly into light. The heart of LED is a semiconductor wafer, one end of which is attached to a bracket, one end is negative, and the other is connected to the positive electrode of the power to encapsulate the entire wafer with epoxy resin.
Semiconductor wafers consist of two parts, one is P type semiconductor, in which the hole dominates, and the other end is N type semiconductor, which is mainly electronic here. But when the two semiconductors are connected, they form a P-N junction between them. When the current passes through the wire acting on the chip, the electrons are pushed into the P region. In the P region, electrons combine with the hole and then emit energy in the form of photons, which is the principle of LED luminescence. The wavelength of light, that is, the color of light, is determined by the material that forms the P-N junction.
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