How Circuit on Board (COB) Lights Work

How Circuit on Board (COB) Lights Work

Describe COB Lights.

Chip on board (COB) LEDs, which are relatively new on the LED market, have many benefits over the conventional options. In order to create a single module, the manufacturer will bond numerous LED chips (typically nine or more) straight to a substrate. Since the individual LEDs used in a COB are chips rather than the conventionally packaged LEDs, the chips can be mounted to take up less room while still maximizing the LED chips' potential. When the COB LED package is powered on, it looks more like a single illuminated panel than it would if several SMD LEDs were mounted tightly together.

Benefits of COB LEDs

Because COB LEDs are multi-chip packed, they can emit far more light per square inch than regular LEDs because their light emitting surface can accommodate several times more light sources.

COB LEDs power its numerous diode chips using a single circuit with only two connections. As a result, less hardware is needed for each LED chip to function properly. Also, the fewer components and absence of the conventional packaging for LED chip structures might lower the amount of heat produced by each LED chip. When connected to an external heatsink, the ceramic/aluminum substrate of COB LEDs also functions as a greater efficiency heat transfer medium, substantially reducing the assembly's overall operating temperature. To make the most of a COB, care must be taken while mounting it to a heatsink. The heatsink should be able to dissipate the heat produced. Over time, proper heat dissipation boosts productivity and reduces failure rates.

The fact that spot soldering of the individual LED chips is not required because each chip is directly placed into the substrate is another feature of COB LEDs that lowers failure rates. The failure rate decreases as a result of fewer welding spots.

When employing COB LEDs, lenses and other conventional LED packaging components are removed, resulting in a significant reduction in light loss and an increase in viewing angle.

One drawback of COB LEDs

One drawback of COB LEDs is that there are now only a few different color options available (blue, green, pink, red, cool white, neutral white, and warm white).

The use of COB LED lighting

The spectrum of COB LEDs' potential applications is extensive. The major purpose of COB LEDs would be as solid-state lighting (SSL) replacements for metal-halide lamps in applications including high-bay lighting, street lighting, and high-output track lights and downlights, while these lights might also be utilized for greater power general lighting.

The fundamental steps needed to power up a COB LED are shown in Figure 2. In this example, a Citizen CLU721 Series COB LED is given a constant 1.05 A from an Excelsys Technologies LXC42-1050SW driver.

The driver can deliver up to 1.05 A to the COB LED (which in this case has a test current of 1.05 A and a maximum rating of 1.38 A) and won't be harmed by overdriving it. The input voltage range for the driver is 90 to 305 VAC. Moreover, drivers function more efficiently and contribute to less losses in the system as a whole when they are operated close to their full capacity (in this case, 39.48 W out of a maximum 42 W).

Conclusion

As designers become more aware of their advantages over the conventional standard LED solutions, COB LEDs are being used more frequently in lighting applications. It is difficult to not consider them for any lighting application design given their ability to fit more LED sources into a smaller space for increased lumen output, their capacity to transfer heat more effectively to a heatsink, the lower failure rates due to their simpler construction, their lower light loss, and their increased viewing angle.

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