LED lamp quality and drive power relationship

Update:24 Aug 2019

LED is the abbreviation of "LIGHT EMITTING DIODE" in En […]

LED is the abbreviation of "LIGHT EMITTING DIODE" in English. It is abbreviated as light-emitting diode in Chinese. Because of its environmental protection, long life, high photoelectric efficiency (current light efficiency has reached 100LM/W), and seismic resistance, it has been applied in various industries in recent years. Rapid development, in theory, the service life of LED is about 100,000 hours, but in the actual application process, some LED lighting designers have insufficient understanding of LED driving power or improper selection or blind pursuit of low cost, resulting in a long life of LED lighting products. Shorter, poor LED lamps last less than 2,000 hours, and some even lower, the result is that the advantages of LED lamps are not well played.

Due to the particularity of LED processing and manufacturing, the current and voltage characteristics of LEDs produced by different manufacturers and even the same manufacturer in the same batch of products have large individual differences. Taking the typical specification of high-power 1W white LED as an example, according to the current and voltage variation rules of LED, a brief description is given. Generally, the forward voltage of 1W white light application is about 3.0-3.6V, that is, when it is labeled as 1W LED. When the current flows through 350 mA, the voltage across it may be 3.1V, or it may be other values ​​at 3.2V or 3.5V. To ensure the life of 1WLED, the general LED manufacturer recommends that the lamp factory use 350mA current. Drive, when the forward current through the LED reaches 350 mA, the small increase in the forward voltage across the LED will cause the LED forward current to rise sharply, causing the LED temperature to rise linearly, thereby accelerating LED light decay. To shorten the life of the LED and even burn out the LED when it is serious. Due to the particularity of the voltage and current changes of the LED, strict requirements are imposed on the power supply for driving the LED.

LED drive power is the key to LED luminaires. It is like a person's heart. To manufacture high-quality LED luminaires for lighting, it is necessary to abandon constant voltage to drive LEDs.

Many high-power LED packaging plants now seal many individual LEDs in parallel and in series to produce a single 20W, 30W or 50W or 100W or higher power LED, even before the package. They are strictly selected and matched, but there are dozens and hundreds of individual LEDs due to the small internal quantity. Therefore, the packaged high-power LED products still have great differences in voltage and current, and Compared with a single LED (generally a single white light, green light, blue light operating voltage of 2.7-4V, a single red light, yellow light, orange light working voltage of 1.7-2.5V) parameters are even more different!