SMD LED, also known as SMDLED, is a simple L.ED lamp bead. Its light-emitting principle is to pass current through compound semiconductors, and through the combination of electrons and holes, excess energy will be released in the form of light to achieve luminescence. Effect.
It can directly convert electricity into light. Its voltage is 1.9-3.2 days. The red and yellow light voltages are low. The heart of the LED is a semiconductor chip. One end of the chip is attached to a bracket, one end is negative, and the other end is connected to the positive pole of the power supply, so that the entire chip is ringed. Oxygen resin is encapsulated. The semiconductor wafer is composed of two parts, one part is a P-type semiconductor, and the other end is an N-type semiconductor, here are mainly electrons. But when these two semiconductors are connected, a P-N junction is formed between them. When the current acts on this most piece through the wire, the electrons will be pushed to the P area, where the electrons and holes recombine, and then emit energy in the form of photons. This is the principle of LED light emission. The wavelength of light is also the color of light, which is determined by the material forming the P-N junction.
With the development of SMD LEDs from time to time, in order to obtain high profits, some manufacturers have caused a large number of unqualified products to go on the market. This violates the true value of LED energy saving, short-lived, environmental protection, etc. How to distinguish the advantages and disadvantages of SMD LEDs, the reporter interviewed Huibo Lighting R&D engineer, summarized the following tips:
1. Finish the appearance of the lamps. The SMD LED produced by the big factory has a smooth appearance and rich texture. After multiple processes, the appearance will never rust or fade. 2. Circuit design. Poor circuit design will greatly reduce the service life of the lamp, and the power factor is low. No matter how good the lamp bead is used, the life of the patch will not be long.
Third, the quality of the lamp beads. The quality of the lamp beads determines the quality of the chip and the packaging technology. Some small manufacturers, in order to reduce costs, use the lamp beads produced by domestic third- and fourth-line manufacturers, while some large manufacturers, such as Tongjia Optoelectronics, all use imported lamp beads, such as Taiwan Epistar, American Kerry et al. Fundamentally guarantee the quality of SMD LEDs.
4. Drive power. Compared with other parts of the lamp, the service life of the power supply is much shorter. The service life of the power supply affects the overall life of the lamp. The theoretical life of the lamp bead is 50,000 to 100,000 hours, while the life of the power supply is 0.2 to 30,000 hours. Design and material selection will determine the service life of the power supply.
5. Heat dissipation. SMD LED heat dissipation is also very important. If the heat dissipation conditions are not good, the lamp bead will work at high temperature for a long time, the light decay will be great, and the life of the lamp will be reduced.
6. Safety regulations and certifications. Before leaving the factory, high-quality SMD LEDs have been inspected by professional equipment, while some small manufacturers rely on purchasing parts for processing and assembly without inspection and certification.
