Conformal Coatings for LED Applications

Conformal coatings elevate the performance of LEDs. Whether it’s enhancing color accuracy, providing protection against damage, or ensuring optimal electronic performance, conformal coating extends the applicability of LED technology. Discover the top six ways in which conformal coating and LEDs complement each other seamlessly.

1. UV Resistance

Many types of LEDs are sensitive to the ultraviolet (UV) radiation that emitted by the sun. Over time, these LEDs gradually yellow and experience reduced light output. While some conformal coatings do not protect LEDs from UV, others like special types of Parylene, block the light and its yellowing effects. Conformal coating of LED electronics that are outside can help to make the displays last longer while maintaining the vivid colors that LEDs are known for.

2. Moisture-Resistance

Placing LEDs outdoors exposes them to harsh weather conditions, with water contact posing a significant risk of damage. Silicone conformal coatings can be applied relatively thickly, providing a large margin of error to prevent water from reaching and damaging the LEDs and the circuitry that drives them. Parylene coatings have also been shown to have a high degree of success preventing moisture damage to LEDs.

3. Chemical Protection

Applying a conformal coating to LEDs serves as a shield against chemicals. Urethane conformal coatings and Parylene, in particular, safeguard LEDs from solvents encountered in automotive settings. Beyond protecting outdoor LEDs from salt, these coatings play a vital role in protecting consumer electronics used near the human body, which can produce sweat and other substances.

4. Optical Clarity

Many conformal coatings are optically transparent. This means that they can add protection to LED displays without the risk of glare or distortion that can come with adding a cover glass over them. At the same time, they’re also usually relatively light and thin. A truly conformal coating over LED electronics, like the kind that Parylene offers, is also completely uniform, minimizing the risk of any distortion or refraction of the light.

5. Electrical Insulation

Numerous conformal coatings also serve as excellent dielectrics. When conformal coatings are applied to the backside of LED electronics, they seal the components off from each other. This helps to reduce the risk of any short circuits occurring when parts shift or when conductive materials fall on the PCB.

6. Tin Whisker Management

Unfortunately, some connections are prone to the formation of tin whiskers. These are small conductive bridges of tin that gradually grow out of tin-coated surfaces and can cause short circuits. One of the best ways to manage them is through the use of conformal coatings. Coating LED electronics with materials like urethane addresses the issue in two ways. Firstly, it inhibits whisker growth and encases any growth within a dielectric barrier. Secondly, even if a whisker manages to breach the coating, it will encounter a conformal coating barrier on the other side, rather than making direct contact with a bare conductor. As LEDs are used in new applications, the significance of conformal coating for LED electronics will remain crucial.

To learn more about how conformal coatings can elevate the performance of LEDs, contact SCS.