At present, there are non isolated designs and isolated driving power sources in the general LED lighting market.
Non isolated designs are limited to double insulated products, such as alternative products of light bulbs. The LED and the entire product are integrated and sealed in non-conductive plastics, so the end user is not in any danger in electric shock. The secondary products are insulated and the price relatively expensive, But in places where users can access LEDs and output wiring (usually in LED lighting and street lighting applications), this product is essential.
LED drive power with isolation transformer or electrical isolation means that the LED can be directly touched by hand without electric shock. The LED drive power without isolating transformer can still achieve partial mechanical insulation by means of protective enclosure. But at this time, LED can not contact directly at work.
 
 

   Insulating bulbs will become main stream in the future.
Physical design determines whether the driver is isolated or non isolated. Safety rules usually require two separate isolation layers. Designers can choose between two physical isolation layers, a plastic astigmatic mask and a glass shield, and use a non-isolated power supply. If physical isolation costs are too high, and mechanical difficulties exist, or too much light is absorbed, electrical isolation must be solved in the power supply. The isolated power supply is usually larger than the non isolated power of the same power level. Lighting designers have to do a lot of cost and design optimization for each product they design.
 

    Designers will always have different opinions from different perspectives as they apply to different applications, whether to use insulated transformers or to use insulated lampshade enclosures. Usually, they are analyzed in many ways, such as cost and manufacturing process, efficiency and volume, insulation reliability and safety requirements, and so on.
The drive cost of the transformer is higher, but it also makes the LED lamps more practical, which can meet the needs of the end user accidental contact with the LED. When the incandescent lamp glass enclosure is easily damaged, an E27 ordinary bulb can be replaced by an LED lamp. In addition, lamps and lanterns used in industrial areas or office equipment do not require contact with end users, such as street lights and mall lighting, and LED lights do require isolation transformers.
 

    As a product that enables end users to use safely, the reliability of insulation and isolation will be considered. As a complete product, the part of the product surface that the user can touch must be isolated from the electric shock. As far as the whole system of the product is concerned, isolation is unavoidable. The difference is only that the location of isolation is different. Some designers use isolated transformers, s So they can simplify the design of heat dissipation and lampshade. If a non isolated drive design is adopted, a reliable insulation requirement must be considered in the structure of the lamp housing. Therefore, as power driven, isolation and non isolation schemes exist all the time.
 

    The main challenge facing Chinese LED driver manufacturers is to find low-cost AC / DC drives to meet stricter power factor and efficiency performance in low-cost power systems.

    In the future, the use of high-quality, reliable power in space-constrained and difficult-to-dissipate systems (such as LED lamps) will no longer be free. However, it is difficult to prove a high quality bulb before the end user has used many bulbs with a life span of about 10,000 hours.

    The isolated LED driver based on transformer will be the mainstream.
Isolated and non isolated LED drive power schemes have their own advantages and disadvantages. We think that ClassII will be the mainstream because it simplifies the LED heat dissipation problem. The ClassI or II system depends on the grounding system. In most cases, it has a lot to do with the location of the installation. ClassII is more common. It requires two level or enhanced isolation, and transformer windings, insulation belts and physical isolation are also required. The ClassI system requires a grounding enclosure and / or mechanical obstacle while the ClassII system does not need it.
There are several trends that are driving the development of LED lighting market.The first is the continuous improvement of high brightness LED efficiency and the emergence of high reliability constant current LED drive power supply with very high efficiency. Secondly, global legislation prohibits incandescent lighting (due to its low efficiency) and the gradual fading of CFL energy saving lamps.( If it breaks, it will flow out of mercury that is harmful to the environment.) The combination of these factors is making LED lighting a long-term trend. Of course, low system costs (including LEDs, thermal management systems, and LED drivers) will always be the driving force behind the widespread adoption of LED universal lighting by consumers.
In fact, in many LED lighting products, failure is a common phenomenon, mostly because of power failure, not LED failure.
At design level, this means that OEM must become an expert in system thermal design. LED provides high efficiency, but they also produce more heat conduction than incandescent or energy-saving lamps. Because many LED lighting applications are enclosed in a very small space, it is difficult to use ventilation to dissipate heat. Without careful thermal design, LED and power-driven circuits can easily degrade or permanently fail due to high temperatures.