What are the factors that distinguish the quality of LED? How to tell the difference between two types of LEDs? In fact, choosing high-quality LEDs can start from the chip and continue until assembly is complete, during which there are many factors to consider. Tier One LED manufacturing companies are able to produce high-quality and consistent wafers starting from high-quality LED manufacturing materials, which in turn can produce excellent chips. The chemical materials used in the wafer production process are a significant factor in determining all performance indicators of LEDs.

A 2-inch wafer can cut over 6000 LED chips, with only a few chips having different performance indicators compared to the whole. The difference in color, brightness, and voltage drop between chips manufactured by an excellent chip manufacturer is very small. After the packaging of LED chips is completed, there may be significant differences in many performance indicators, such as viewing angle. In addition, the influence of packaging materials is also significant, for example, silicone resin has better performance than epoxy resin.

Classification ability

Excellent LED manufacturers not only produce high-quality chips, but also have the ability to classify and package LEDs based on their color, brightness, voltage drop, and viewing angle. High quality LED suppliers will provide customers with products with consistent working characteristics, while lower quality LED suppliers can only provide LEDs similar to "mixed" ones.

For high-end applications with strict quality requirements, such as airport runway boundary lights, they must meet FAA level color and brightness specifications. To ensure performance and safety, the consistency of LED packaging is also strictly limited. LEDs with poor packaging grade used in strict application fields can lead to a series of inconsistency issues such as premature failure, which is likely to cause major accidents. In order to avoid equipment shutdown and ensure the reliable working characteristics of the LED specified in the design, it is quite important to avoid using "mixed" products in high-end and quality demanding applications.

Product matching capability

In addition to discrete LEDs, the assembly and power supply of LEDs have a significant impact on their performance, brightness, color, and other indicators. Due to factors such as ambient temperature, operating current, circuit structure, voltage spikes, and environmental factors that can all affect the performance indicators of LEDs, proper circuit design and assembly are key to protecting LEDs and ensuring performance. LED manufacturers also use various technologies and materials to design circuit structures and assemblies. In most cases, differences in the experience of LED assemblers can result in differences in overall performance and reliability of LEDs in the same application.

With the rapid growth of LED demand, manufacturers and assembly plants serving the global market are also rapidly increasing. Unfortunately, the surge in support manufacturers not only heavily adopt low-quality LEDs, but their packaging and LED design engineers are also relatively inexperienced. Therefore, in addition to accurately screening LED suppliers based on existing experience, OEM manufacturers must also examine their circuit design and assembly techniques to ensure compliance with design specifications, as well as whether the design provides sufficient heat dissipation capacity, as overheating is the main factor causing LED failures and inconsistent performance.

Collaborative vendor testing

In order to eliminate unfairness in testing, many companies entrust third-party manufacturers to test the assembly and circuit structure of LEDs. An LED device may be tested or used for several weeks in harsh environments. During the testing process, pressure, temperature cycling, voltage fixation/variation, current fixation/variation, and other harsh environmental tests are conducted simultaneously to determine whether the LED meets the application requirements. A large number of parameter changes that occur before and after testing must be recorded, and the changes in the brightness, color, and voltage drop of the tested LED must be monitored.

Accelerated lifecycle testing is a key test to avoid failures in special application areas. Testing helps ensure the screening of LEDs that are expected to work for at least 100000 hours but fail prematurely after only 1000 hours of operation. This situation is possible because low-quality LEDs (or high-quality LEDs that are improperly assembled and designed) will experience a decrease in brightness after 1000 hours of operation. In fact, if a low-quality LED has a higher driving current, it will be brighter than a high-quality LED in the early stages of operation. However, excessive current will cause the LED to heat up too quickly, resulting in a decrease in brightness or burnout.

In addition, there are also examples where assembly technology has a greater impact on LED performance to some extent than the chip itself. Design engineers should request reliability specifications for LEDs from LED suppliers, and also conduct assembly tests on LEDs to ensure that those with higher brightness are indeed better. Some excellent LED suppliers can guarantee the reliability of their LED assembly technology for three years or longer, and can further provide final LED products that include high-quality LEDs and appropriate designs for specific applications.

Reasonable use

Not every application requires high-quality LED assembly technology. If the assembly of LED does not meet the requirements of harsh environments, the application may not necessarily pose significant safety risks, or if the maintenance cost of the final product is not very high, using inferior assembly techniques may be more suitable.

The most fundamental point is that LEDs must be affordable. Therefore, within the cost constraints, it is necessary to consider factors such as the packaging level of the supplier's products, assembly design experience, and testing. Designing to meet application and market demands is the most effective means of serving end-users. If the application requires high-end solutions, the selection of chip suppliers, design experience, and testing should all be considered factors. If we do not consider the sales price of high-end products, we should carefully consider other relevant factors that distinguish good and bad LEDs. LED suppliers with the ability to classify packaging levels and manufacturers capable of conducting reliability and accelerated lifecycle testing can engage in long-term cooperation, which helps manufacturers develop high-end products using more reliable LEDs.