APPLICATIONS OF ALUMINUM PCBS:

Although Power Converters and LEDs are the largest users of these products, Automotive and RF companies are also looking to take advantage of the benefits of these constructions. While a single layer construction is the simplest, other configuration options are available at Amitron, including:

1. FLEXIBLE ALUMINUM PCBS

One of the newest developments in IMS materials is flexible dielectrics. These materials feature a polyimide resin system with ceramic fillers which provides excellent electrical insulation, flexibility and of course thermal conductivity. When applied to a flexible aluminum material like 5754 or similar, the product can be formed to achieve a variety of shapes and angles which can eliminate costly fixtures, cables and connectors. Although these materials are flexible, they are intended to be bent into place and remain in place. They are not suited for applications that are intended to be flexed regularly.

2. HYBRID ALUMINUM PCBS

In a ‘Hybrid’ IMS construction a “Sub-assembly” of a non-thermal material is processed independently and then bonded to the aluminum base with thermal materials. The most common construction is a 2-Layer or 4-Layer Sub-assembly made from conventional FR-4. Bonding this layer to an aluminum base with thermal dielectrics can help dissipate heat, improve rigidity and act as a shield. Other benefits include:

• Less costly than a construction of all thermally conductive materials

• Provides superior thermal performance over a standard FR-4 product

• Can eliminate costly heat sinks and associated assembly steps

• Can be used in RF applications where a surface layer of PTFE is desired for its’ loss characteristics.

• Use of component windows in the aluminum to accommodate through-hole components. This allows connectors and cables to pass connections through the substrate while the solder fillet creates a seal without the need for special gaskets or other costly adapters.

3. MULTILAYER ALUMINUM PCBS
Common in the high performance power supply market, multilayer IMS PCBs are made from multiple layers of thermally conductive dielectrics. These constructions have one or more layers of circuitry buried in the dielectric with blind vias acting as either thermal vias or signal vias. While more expensive and less efficient at transferring heat as a single layer designs, they provide a simple and effective solution for heat dissipation in more complex designs.