Small, Smart and Connected LED Drivers Through Design Innovation!

ERP Power meticulously considers a combination of factors to produce very small, smart and connected LED drivers which are efficient, reliable and cost effective. The ERP Power 2017 platform designs deliver up to 24W per cubic inch of power density at a time when other manufacturers are providing only 8W per cubic inch. Higher power density means the driver shrinks in size while maintaining the same power output.

Achieving higher power density increases in difficulty as the power level of the driver drops. Achieving 20W per cubic inch at 150W is many times easier than achieving the same 20W per cubic inch density at 30W due to the fixed overhead of non power related requirements. These attributes, like EMI compliance and basic safety isolation requirements are somewhat fixed and occupy available space quickly at lower power levels.

Over the last decade, LED component technology has rapidly matured. Highly efficient and very small LEDs are available from a variety of reputable LED manufacturers. These LEDs are so efficient that lighting designers are no longer interested in a few more LPW (lumen per watt) in LED performance. The new challenge for the lighting fixture designer community is to create the most aesthetically pleasing, slim and sleek LED fixture design.

Unfortunately, the LED driver industry has been slow to adapt and provide high power density drivers, therefore limiting the imagination and creativity of LED lighting fixture designers. Very compact drivers from ERP Power enable designers to achieve LED lighting fixture designs that were unthinkable a few years ago. Aside from dramatic weight reduction, reducing the size of drivers plays a major role in producing aesthetically pleasing, slick and slim fixtures by completely hiding the bulky driver. By utilizing very small drivers, the unappealing external canopy (driver housing) or the large space within the chassis of the fixture can be totally eliminated or dramatically reduced in size.

Below are some of the key factors ERP Power utilizes to achieve power densities seemingly unattainable by many other driver manufacturers.

Integration: One of the key factors for size reduction is integration. ERP Power uses the latest and most integrated ICs from very reputable IC manufacturers, albeit at a higher component cost.

Topology and Innovative Circuit Design: ERP Power design engineers meticulously select a driver topology to achieve the highest efficiency in a small footprint. Then, through innovative circuit design techniques, ERP design engineers minimize the number of components, which reduces the size and cost of the driver. Over the past decade, ERP design engineers have mastered the fine art of balancing the driver performance, reliability, and cost. The most advanced high power density platforms today are utilizing sophisticated resonant converter approaches for power processing. These types of converters utilize the concepts of natural resonance to generate the power conversion more efficiently than forced communication type designs used in lower density approaches. Development teams at ERP have developed LLC type resonant converters used by some of the most demanding computing manufacturers in the word – Apple, Dell, HP and IBM/Lenovo to name a few.

Mechanical Size Reduction = Small LED Drivers: Every component is analyzed in order to select the most compact version without sacrificing performance. Pushing this concept to its limits, ERP Power may build some components (such as magnetics) that do not exist in the industry at the desired density or shape.

Owning the Manufacturing Facility: ERP Power owns its manufacturing facility which can facilitate building certain custom electronic components or building boards that other third party CMs would not entertain for a variety of reasons. This in-house manufacturing expertise provides ERP Power the flexibility to build more compact drivers.

Layout and Mechanical Design: ERP Power puts a tremendous amount of care into the layout of PCBs and the mechanical design of the drivers to achieve the highest power density possible. By utilizing 3D design techniques, the amount of empty space left on the board and within the driver housing is drastically minimized. Minimizing noise paths and optimizing the flow of energy through the converter are paramount to success in high density design.

Efficiency and Thermal Design: Without a high level of driver efficiency, ERP Power would not have been able to achieve the tremendous amount of size reduction while maintaining high reliability and a long lifetime. As the driver size shrinks, the contact area of the driver to the heatsink also shrinks, hence transferring less heat to the heatsink or chassis of the LED lighting fixture. To achieve the same max Tc (case temperature) of 90°C and a very long predicted lifetime, the efficiency of the driver is maximized by innovative circuit designs to reduce the thermal load of the driver.

Several thermal design techniques are used to keep the sensitive components as cool as possible. The ERP drivers are potted to conduct heat more uniformly to the bottom and the body of the driver. The entire driver contact surface area is fully utilized to make thermal contact with the heatsink or the chassis of the LED lighting fixture. Fully utilized driver contact surface allows a smaller thermal contact surface to be required to achieve the same case temperature.

Additionally, the high operating frequency of the designs, averaging about a quarter megahertz, enable the removal of all but one chemical electrolytic capacitor (which is the weakest link in power design reliability). This enables ERP to deliver a power curve with 5-year reliability points at full max case temperatures of 90°C.

Although ERP Power uses many innovative thermal design techniques in the driver design, LED lighting fixture designers must also employ sound thermal design considerations for effectively transferring the heat from the driver and the LED board into ambient air. The lower the Tc, the longer the lifetime of the driver, and most importantly the higher the reliability of the system during the useful life of the driver. It is highly recommended to refer to the Thermal Design Considerations and Basic Modes of Heat Transfer appnotes and thermal design videos available on the ERP University website. Below are links to these thermal design resources.

ERP Power Appnotes:

Technical Documentation

Thermal Design Videos:

In summary, ERP Power thrives on innovation, as evidenced by many LED driver industry firsts such as tri-mode dimming and 24W per cubic inch high power density which results in very compact driver size.