LED drive power must need aluminum electrolytic capacitor?
2018-04-11 19:00:08
[Ancient China Aluminum Network] An important reason for the low life of LED driver power supply is the insufficient life of the aluminum electrolytic capacitor required for driving the power supply. The main reason is that the ambient temperature inside the LED lamp is high during long working hours, resulting in aluminum electrolytic capacitors. The electrolyte is quickly depleted and its life is greatly reduced. Generally, it can only work for about 5,000 hours. The life of the LED light source is 50,000 hours, so the working life of the aluminum electrolytic capacitor becomes a short rib of the life of the LED driving power supply. Now some vendors have solved this problem by inventing a LED driver solution without aluminum electrolytic capacitors. However, not all LED driver power suppliers agree with this approach. Chen Hao pointed out: "There is currently no one in the LED lighting drive power supply that is currently in mass production. The drive scheme for electroless capacitors is used because without it, many test standards cannot be passed, such as EMI test and flicker-free test." The LED driving power scheme using aluminum electrolytic capacitors is usually easily tested above. What if the film capacitors and ceramic capacitors or tantalum capacitors are replaced? The film capacitors must have the same capacitance (typically 100-220uF). Will be very large, and the cost is too high, the ceramic capacitor capacity is too small, such as the use of multiple ceramic capacitors to achieve such a large capacity, accounting for the area and cost are too large, tantalum capacitors to have such a large capacity, one is too expensive , but the pressure is too low to meet the requirements, so replaced by any other kind of capacitor, basically is not too bulky, it is too expensive, such as for these shortcomings into a smaller capacity capacitor, eliminating the effect of ripple Not so good, many of the strict certification test indicators required for export products can not pass, so the current high-quality LED drive power is still commonly used aluminum electrolytic capacitors. Many suppliers claim that the electrolytic capacitor-less LED driver power supply solution is likely to only remove the aluminum electrolytic capacitor at the AC input, and the aluminum electrolytic capacitor at the constant current output should be difficult to remove or replace. From the perspective of the LED drive power supply structure, Chen Hao said that Japan and the United States will mainstream non-isolated solutions because their power grid input voltage is only 110V. In China and Europe, an isolated solution will be the mainstream, because their grid input voltage is as high as 220V, and the security of the isolation scheme is guaranteed, although the cost may be higher.