Advantages and disadvantages of various packaging formats for high-power LEDs from the perspective of automotive headlights

LED car headlights offer significant advantages, such as an extended lifespan, high brightness, and enhanced beam reach, making them the preferred lighting solution for replacing halogen and xenon lamps in large-scale applications. These headlights have also become a key trend in next-generation automotive lighting systems.

Although LEDs are a new type of light source, in the automotive parts and aftermarket markets, their design still adheres to the dimensions and mounting methods of original LED headlight bulbs due to the need to fit seamlessly into the vehicle’s headlight housing system. Meanwhile, the interface, power supply, control mechanisms, shape of the light-emitting area, brightness, and luminous flux must closely match those of halogen and xenon lamps.

When replacing halogen and xenon lamps, no significant modifications to the lamp housing are required. As a new, alternative light source, LED-based automotive headlights should deliver a fresh experience to users—not only in terms of lifespan and reliability but also by significantly enhancing visibility without increasing, or even reducing, glare. Additionally, they should improve ground illumination and projection distance.

As a mature light source, LEDs are widely used in lighting, backlighting, displays, and other applications. High-power LEDs are characterized by their compact size, high current capacity, and exceptional reliability—and are primarily employed in directional projection lighting systems such as automotive headlights, motorcycle lamps, pico projectors, stage lighting, portable dazzle lights, ultra-long-range spotlights, and more. Currently, automotive and motorcycle headlight systems commonly utilize high-power LED packages, including COB (chip on board), CSP-COB (chip scale package–COB), 2016 LEDs, or CSP LEDs, as well as high-performance ceramic-based LEDs and LED modules specifically designed for automotive headlamps.

Due to the limitations of the packaging shape, chips in high-power ceramic-based LEDs can only be arranged in a square configuration. Clearly, when high-power ceramic-based LED automotive lamps are installed in an overall luminaire, much of the light emitted outside the linear illumination zone ends up as harmful scattered light and glare—this not only fails to enhance the effective brightness of the road surface but also distorts the intended light pattern and disrupts the desired brightness distribution of the projected beam. Moreover, high-power ceramic-based LEDs are sensitive to substrate size constraints, resulting in relatively bulky designs. The main product types include 7070, 5050, and 3535. To maximize luminous flux, however, placing two closely spaced high-power ceramic-based LEDs on a narrow automotive headlight PCB will inevitably lead to dark spots, causing even greater light loss than any potential gain in brightness.

Despite the insurmountable drawbacks of high-power ceramic-based LEDs when used in automotive headlights, they still remain in demand on the market thanks to their relatively mature packaging and high luminous efficiency. Currently, most LED automotive bulbs rely on high-power ceramic-based LEDs. The main domestic and international suppliers include CREE in the U.S., LG in South Korea, Weitian from Taiwan, and Jingrui in Jiangxi. However, with the emergence of linear high-intensity LED light sources that offer superior value for money and enhanced user experiences—such as the 2016 LEDs and CSP-COB technologies described below—the application of high-power ceramic-based LEDs in automotive headlights could gradually be phased out.

From the simple analysis above, it is clear that in the automotive parts and aftermarket markets, replacing traditional halogen and xenon lamps remains the dominant practice. High-intensity LED-based automotive bulbs must closely match halogen and xenon lamps in terms of physical dimensions, mounting methods, interfaces, power supply and control systems, as well as the shape and characteristics of the light-emitting area, brightness, and luminous flux. While the production cost of conventional COB LEDs is low, their reliability and beam pattern are relatively poor, leading to their gradual displacement from the mainstream market.

Due to inherent limitations and high costs, the use of high-power ceramic-based LEDs in automotive headlights will gradually be replaced by linear, high-brightness LEDs that offer a better price-to-quality ratio and superior user experience. A linear LED light source can consist of either 2016 LEDs arranged in a line on a printed circuit board, or 5050 and 7070 CSP-COB LEDs. However, five-sided CSP LEDs are not suitable for creating highly reliable automotive headlight systems. LED modules for automotive headlights are primarily used in both the factory-installed market and the aftermarket auto parts sector, where they are specifically designed with custom LED modules tailored for vehicle headlight applications.