COB integrated light source and LED light source are two well-known lamps in today's lighting industry. The difference is that LED integrated light sources generally use large-size and high-power LED chips of more than 1 watt, and the chip size is generally more than 30MIL. The COB light source is mainly low-power LED chips less than 1 watt, and a very small amount of COB light sources will also use high-power LED chips above 1 watt. There are some similarities in their overall characteristics. Here is a detailed analysis for everyone.
COB integrated light source characteristics
Integrate several low-power LED light sources into a bracket to get the light source to be an integrated light source. Generally refers to the packaging form of CHIP on Board, which is commonly known as cob packaging, which means that several chips are directly attached to the substrate, and they are packaged together with silica gel, epoxy resin or other materials. The yellow one is phosphor. The main problem in lighting applications is that heat dissipation leads to phosphor volatilization and lens aging. COB integrated light sources are widely used in LED bulbs, LED lamp cups, LED spotlights, LED downlights, LED ceiling lights, LED bean gall lights, and are currently one of the mainstream trends of LED lighting sources. COB integrated light sources mainly include the following Features:
1. It can be freely matched and combined to form a variety of LED lamps, which is easy to assemble.
2. High reliability, no dead lights, no plaques.
3, the light is uniform, the light is soft, no glare, and does not hurt the eyes.
4. High color rendering index and high luminous efficiency.
5. Under normal current, the attenuation is the smallest, and it is controlled to be less than 3% within 1000H.
6. It is safe and reliable, all working under 50V, which fully considers the application certification.
7. Green and environmentally friendly, no pollution.
LED, high efficiency and energy saving effect, has been given the title of green lighting by people. From the analysis of LED lighting products, COB integrated light source as a light-emitting element has always been the core of the development of LED. The understanding of COB integrated light source can be divided into the following aspects. The first is to use thermally conductive epoxy resin on the surface of the substrate (usually mixed with Silver particles (epoxy resin) cover the silicon wafer placement point, then place the silicon wafer directly on the surface of the substrate, heat treatment until the silicon wafer is firmly fixed on the substrate, and then use wire bonding to directly establish between the silicon wafer and the substrate Electrical connection. Compared with traditional aluminum substrates, ceramic substrates have higher reflectivity, which helps to improve light efficiency. Ceramic has the characteristics of high reliability and long life. The coefficient of thermal expansion and contraction of ceramics is small, and its surface is relatively flat even in a high temperature environment, which helps to dissipate heat. It is easy to assemble, and the ceramic substrate cob light source can be directly assembled on the radiator through thermally conductive glue. The high thermal conductivity of ceramics can ensure that the LEDs of Guangtuo Optoelectronics have the industry-leading thermal lumen maintenance rate (95%). Ceramics are insulators, which help LED lighting products to pass various high voltage tests and can withstand high voltages above 4000v.
