Chip-on-board or "COB" refers to the mounting of bare LED chips in direct contact with a substrate (such as silicon carbide or sapphire) to produce an LED array. COB LEDs have many advantages over older LED technologies, such as surface mount device ("SMD") LEDs or dual in-line package ("DIP") LEDs. Most notably, COB technology allows for higher LED array packaging density, which is what optical engineers call an improved "lumen density." For example, using COB LED technology on a 10mm x 10mm square array, compared with DIP LED technology, the number of LEDs is 38 times the former, and compared with SMD LED technology, the number of LEDs is 8.5 times the latter. This leads to higher light intensity and greater uniformity. In addition, the use of COB LED technology can greatly reduce the footprint and energy consumption of the LED array while maintaining constant light output. For example, a 500 lumen COB LED array can be many times smaller than a 500 lumen SMD or DIP LED array, and the energy consumed is also greatly reduced.
Another huge advantage of using COB LED technology is that, no matter how many diodes, the COB device has only one circuit and two contacts on the entire chip. This single circuit design, no matter how many diodes are on the chip, makes the other parts of the LED device simple.
Why are COB LEDs so important when battery-powered?
When designing battery-powered lighting systems, there is always a trade-off between the number of high-quality lumen outputs (ie, brightness) and the length of battery-operated runtime. Historically, the higher the brightness of high quality, the shorter the running time (assuming you are using the same size battery). However, with the recent development of COB LED technology, this trade-off has become less important. Very low-power COB led can output high-quality, super-bright light for the first time. Therefore, a relatively small and light-weight lithium-ion battery pack can provide long-term power for COB LED-based lighting systems. In fact, our 6W COB LED will run for 14-15 hours using our very small and lightweight (1.25 pounds) rechargeable mobile power center. Using a relatively small battery to output high-quality light for a long period of time was impossible a few years ago! This is why COB-based LED lights are the only ones when we design ultra-bright, ultra-efficient lighting systems select.
All in all, onboard LED is the latest and most advanced technology on the market today. In short, COB LEDs are brighter, consume less energy, and output a higher quality light beam, compared to the older LED technology found in most other trade show lighting today.
The above is provided by down lights cob led chip factory.