r key requirement of the dielectric layer is to be able t.compensate for the different coefficients of thermal expansion of the copper track on the topside of the assembly and the aluminum base plate/heat spreader on the bottom side.
Going three-dimensional Flat sheets of insulated
metal circuit boar.comprising copper foil, a dielectric layer and an aluminum base plate have been available for several years. In the eyes of the forward-thinking LED module designer, the main problem has been that flat sheets of insulated metal circuit board limit them to 2D shapes.
To address these limitations, new dielectric materials are becoming available that have a low modulus, meaning that they ar.compliant with mechanical stress and strain. These materials not only accommodate the coefficient of expansion of the metal elements of the construction, but also enable parts to be formed into right angles, and even through 360°. This enables designers to realiz.complex-shaped designs and ones that form .complete circle with eany attention for the life of the vehicle.
The long life of LEDs also simplifies the designers task because it is less important to make the lighting module accessible for servicing in the finished product. This can result in a neater, more integrated installation and also in potential cost savings.
Temperature modelling Thermal analysis software packages are available to help prove LED based module designs before they ar.committed to manufacture. These software packages gather data from an integrated database about LED performance and specifications along with those of other devices that are mounted on the insulated metal circuit board. This data i.combined with other information about elements of the design, including the copper traces, power and ground planes, and vias. The collated information is then processed to produce an accurate representation of the thermal performance of the design.
User-friendly graphical representations of the results enable the design engineer to quickly pinpoint areas that may require attention, right down t.component and track level.
Thermal analysis software can bring significan.commercial and design benefits by helping speed the time to market and reducing the number of iterations needed to reach a production-ready solution. "
