A COB LED, or chip-on-board LED, is a type of LED that consists of many LED chips mounted on a thermally efficient substrate placed below a uniform phosphor coating. The LED chips are mounted extremely closely together on the substrate, allowing for high intensity or light density to be emitted from a smaller area than is possible with single packaged LEDs. COB technology allows for a much higher packing density of the LED array, which results in improved "lumen density". COB LEDs have a number of advantages over older LED technologies, such as Surface Mounted Device (SMD) LEDs or Dual In-line Package (DIP) LEDs. Some of the advantages of COB LED arrays include:

• High lumen density
• High-quality light output over extended periods of time using a relatively small battery
• A more structural look
• Brighter, clearer lighting
• Wide range of applications, extending from residential to industrial utility

COB LEDs are becoming more popular in lighting applications as designers discover the advantages of employing them over typical standard LEDs. COB LED strips are particularly interesting because of their continuous illumination line without hot spots. COB LED strips are very flexible since their diodes are smaller and placed closer together, so they can curve into tight areas or fit around corners. COB LED strips eliminate hot spots due to their seamless illumination, making them best suited for cases where the light strip is placed close to a reflective surface since it will not show any hotspots in the reflection.