Quality evaluation of a high voltage LED light engine

The concept LED light engine (LED Light Engine) is the earliest known to the semiconductor industry, it is starting to set up and promote ZHAGA Union. The so-called LED light engine refers to the LED package (component) or LED array (module), LED driver , and other overall combination of luminosity, thermal, mechanical and electrical components, under normal circumstances can be directly powered by the mains.

The main purpose of R&D and promotion of LED light engine is to realize the standardization of light source, so that in practical applications, like the traditional lighting products, in the event of failure, the LED light source part can be directly replaced without the need to replace the whole lamp, which is conducive to saving. cost.

In order to further reduce the cost of LED, in addition to the standardized design of the light engine, the semiconductor lighting industry began to appear more and more high-voltage LED design.

The high-voltage LED products discussed in this paper are traditional high-voltage LED products, that is, a plurality of LED chips are connected in series and in parallel by a certain method, and are powered by a high-voltage direct current after simple rectification. The schematic diagram of its circuit structure is shown below:

High-voltage LED products, because they no longer use the LED drive power supply step-down power supply design, only a few components, such as rectifier bridges, resistors, voltage regulators, etc., so the price is relatively low, the scope of use is gradually expanded, including high-voltage LED light Engine design.

Due to the lack of protection of the driving power supply, the safety and performance of the high-voltage LED will be reduced to some extent. When designing as a light engine, in consideration of interchangeable applications, such as installation and disassembly between components, certain high-voltage live parts are more likely to be exposed to the operator, and the safety hazard may be further increased.

Structure and design of a high voltage LED light engine

A certain type of high-voltage LED light engine can be designed as a light source of LED downlight or LED bulb, combined with the power supply of high-voltage LED, with standardized connectors, the structure is convenient to replace. The specific structure is shown in Figure 3 to Figure 6:

From the perspective of product structure and assembly process, the product structure is simple. In addition to the LED chip, the light engine has only a few components such as electrical connectors, rectifier bridges, resistors, ICs, etc. The circuit structure principle is similar to that of Figure 2. Compared with the same type of products, it has a certain low cost advantage.

The connection between the light engine and the heat sink is screwed by metal threads and is also equipped with a threaded light-transmissive light-transmissive cover to form an LED light engine with complete optical, electrical, thermal and mechanical structures. . The luminaire manufacturer can design the luminaire structure according to the structural parameters of the light engine to achieve the replaceability of the light source.