According to the reporter, in recent years, the number of companies developing electroless capacitors or solid capacitors has gradually increased, but they are not mature in technology. Many suppliers claim that the electroless capacitor LED driver solution is mostly just removing the aluminum electrolytic capacitor from the AC terminal. The aluminum electrolytic capacitor at the constant current output is difficult to replace.
Mr. Mao Zhaoqi, Marketing Manager of Yingfeite Electronic Technology in Hangzhou, said that at present, the medium and high power LED lighting drivers produced by Infineon are not using electroless capacitor technology. Usually thousands of hours mentioned in the specification refers to the working life in the extreme working environment. The actual situation is that it can easily achieve more than 50,000 matching with LED chips by improving efficiency, enhancing heat dissipation and using high-quality long-life capacitors. Hours of life. With the drive solution of electroless capacitors, many test standards are difficult to pass, such as EMI test, flicker free test and so on.
Solid capacitor drive solutions such as thin film capacitors, ceramic capacitors, and tantalum capacitors are also available on the market. Such solid capacitors can be classified into three types: inorganic dielectric capacitors, organic dielectric capacitors, and electrolytic capacitors according to the type of medium. Inorganic dielectric capacitors include the well-known mica capacitors and ceramic capacitors that are often seen on CPUs. The comprehensive performance of ceramic capacitors is very good and can be applied to GHz-class UHF devices such as CPU/GPU. However, the general capacity is small, such as using a plurality of ceramic capacitors to achieve large capacity, the board area and cost are too large, and the price is relatively expensive. Organic dielectric capacitors include thin film capacitors that can achieve the same capacitance (typically 100-220uF), but are still very large in size and price.
Electrolytic capacitors mainly refer to tantalum capacitors. The capacity of tantalum capacitors is small, and the price itself is too expensive. The biggest fatal point is that the withstand voltage is too low. As can be seen above, switching to any other type of capacitor is not too large, or the price is too high. If you want to avoid these shortcomings and replace it with a capacitor with a smaller capacity, the effect of eliminating ripple is not so good, and it cannot be certified. .
Electrolytic capacitor technology is still widely used in the industry, and the dielectric of the electrolytic capacitor is a liquid electrolyte. Liquid particles are very active at high temperatures, creating pressure on the inside of the capacitor, but its boiling point is not very high, so there may be a burst. The solid capacitor uses a polymer dielectric. The solid particles are lower in temperature and activity than the liquid electrolyte at high temperatures. At the same time, the boiling point of up to 350 degrees Celsius, in theory, the solid capacitor has almost no possibility of explosion.
The solid capacitor has better performance than the traditional electrolytic capacitor in the equivalent series impedance performance. According to tests, the solid capacitor has a very small equivalent series resistance at high frequency operation, and the conductivity frequency is excellent, and the electrical impedance is reduced. The lower heat output features the most obvious performance between 100KHz and 10MHz. Conventional electrolytic capacitors are more susceptible to ambient temperature and humidity, and are slightly less stable in terms of high and low temperature stability. Even at 55 degrees Celsius to 105 degrees Celsius, the ESR reactance of a solid capacitor can reach 0.1 to 0.3 ohms, but the electrolytic capacitor changes due to temperature.
In terms of capacitance value, the liquid capacitance is below 20 degrees Celsius, which will be lower than the capacitance value indicated. The lower the temperature, the lower the capacitance value will be. At minus 20 degrees Celsius, the capacitance drops by about 13%; at minus 55 degrees Celsius, the capacitance reaches 37%. Of course, this has no effect on the average user, but for manufacturers who use liquid nitrogen as the ultimate overclocking, the solid capacitor can not ignore the impact of the capacitor capacity due to the temperature drop, which leads to a great compromise in overclocking stability. When the solid capacitor is below 55 degrees Celsius, its capacitance drops to less than 5%.
However, the price of solid capacitors is still relatively high, and the capacity of electrolytic capacitors cannot be achieved under the same volume. Therefore, in the case of the LED lighting price is constantly lower, under the premise of meeting the life requirements, liquid electrolytic capacitors are generally selected.
2 in 1 Selfie Stick with detachable blue tooth shutter remote, allows you to take self-snapshot easily or you could separate the blue tooth controller to take group photos and record videos. The only goal of the stick is to help you capture the fun of the moment by blue tooth shutter remote easily.
The maximum length taking snapshot is your arm length plus 27 inch monopod selfie stick ! Imagine that you have two arms length to take self-snapshot and get Face-lift function photos.The folded minimum size 7.87 inch design seems to be more foldable & portable for your pocket or bag perfectly.
Want get satisfying Mufti-angle self-snapshot ?This blue tooth selfie stick tripod stand will achieve your dreams because there are 3 ways to rotate the blue tooth selfie stick tripod by the 225°rotation head with a adjustable knob + 3 modes rotatable phone holder--free combination to get the prefect angle; You can rotate the phone holder and select the phone camera`s using angle (horizontal or vertical or 45°).
Bluetooth Selfie Stick Tripod has High-intensity Aluminum alloy extendable stick and ABS +PC tripod stand with non-slip soft Silicone foot pad that helps the tripod legs won`t slide, so the tripod will be more stable to record video or face time with your family or friends by the remote. Easy to use : Just turn it on, pair it with smart phone via Bluetooth which name is Caiyoule and then take photos or record videos.
Selfie Stick
Selfie Stick,Portable Selfie Stick,Universal Selfie Stick,Bluetooth Selfie Stick
GuangZhou CAIUL Digital Products CO,.LTD. , https://www.caiul-instax.com