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Product Attributes

1．

  LED is a new type of highly efficient and environmentally friendly semiconductor light source device. Compared with other light sources, LED has great advantages in automotive lighting and has a broad application prospect. Different ways of combining LEDs in series and parallel to form LED arrays are used to meet the requirements of automotive lighting intensity.

With the improvement of technology and the rapid development of the social economy, LED products have been widely used in people’s life. 21 century, LED production and market scale have reached an unprecedented level, the most important application market of LED is various places of display, various brands of mobile phones, and so on. In addition, LEDs play an important role in roads, architectural lighting, interior decoration, and many other areas. With the rapid development of the automotive industry, LED driver circuits have been widely used in modern automotive electronics, and previous automotive light sources such as headlights are gradually being replaced by them. At the same time, LED has high luminous efficiency, a short response time (fast response), compact structure (small size), long service life, and other characteristics, it will be used in automotive headlights and also has strong color discrimination and anti-glare characteristics. However, due to the limitations of various factors, LED still has certain defects, need to continue to improve LED technology, to better meet the needs of automotive electronics.

2.

   LED is a semiconductor device light emitting diode, which is made of certain compound semiconductors. LED is a light source with good resistance to vibration and shock, it is protected by an epoxy resin cap, the core is very small, and the core is a P-N junction core, so it has the characteristics of a P-N junction, i.e. forward conduction, reverse cut-off and overvoltage breakdown, etc. In certain special Under certain special conditions, it can also be characterized as a light emitter.

3.

   LED drive circuits are divided into two types of drive: constant voltage drive and constant current drive. Due to the constant current drive type LED, in the structure of the P-N junction-based, can be an exponential relationship to represent the LED voltage and current changes, so it the more widely used. Constant-voltage driving method generally is the use of resistive capacitance step-down or transformer step-down filtering, the use of voltage regulator diodes or switching power supply method, to the LED power supply, but the LED light characteristics will be in the current constantly changing under the corresponding impact. The linear regulator in the constant current drive method has two types: parallel and series, the core is the power triode or MOSFET working in the linear zone as a dynamically adjustable resistor to control the load. the voltage and current at both ends of the LED are not a linear relationship, cannot be powered directly by a voltage source, and needs to be limited by limiting the current to prevent excessive current and avoid damage to the LED. the LED luminous flux and current are not The luminous flux is not proportional to the current, the luminous flux increases with the current, they bear different degrees of electrical power, internal resistance, and potential barriers are not the same, so they cannot be used directly in parallel. Select the correct and reasonable drive mode should consider the application and its functional rationality, for any kind of mode, are required to choose in the switching power supply control mode, the application more common are PFM, PWM mode, and slide film control, which is simple and flexible PWM control mode structure, can maintain a stable frequency in operation, but also need to consider from the energy-saving point of view and other directions, to improve LED instantaneous brightness, and reduce LED power consumption.