Metal core PCB (MCPCB) or insulated metal surface (IMS PCB) are types of metal-based PCB. It is a technology developed to overcome the thermal limitations of FR4 material. If your boards need to work in a high temperature environment, metal material is a better choice than FR4. MCPCB is based on a metal with high thermal conductivity, and the electrical insulation is ensured between the copper and body material, by using a special dielectric. Aluminum, copper and iron can be used as common metal materials. Aluminum is the most common of the metal materials. Such PCBs are generally known as Aluminum PCB.
Metal Core PCB Technology
It is available as single-layer, double-layer and multi-layer PCB. The choices vary depending on the individual PCB application needs. As the layer increases, your cost increases as well.
METAL CORE PCB STACK-UPS
SINGLE LAYER
The metallic base transfers heat to the cooler, to an installation surface or directly into the air. Materials are placed on a single surface.
DOUBLE LAYER
Plated through holes (PTH) can be made with special processes. Thus, SMT and THT components can be placed on both sides.
MULTI-LAYER
The SMT components are placed on one side only. THT components are not allowed, but it provides the possibility of making blind and embedded vias with built-in signal layers.
“If you have FR 4 cards in hand, you typically need to add a heat sink to transfer heat away from the board, otherwise it will create potentially damaging hot spots.”
How Do Metal Core PCBs Dissipate Heat?
The reason why Metal Core PCBs are much more effective at dissipating heat than FR4 boards is due to their dielectric material, which acts as a thermal bridge from the IC components to the metal plate, conducting the heat from the core to a heat sink automatically. If you have FR 4 cards in hand, you typically need to add a heat sink to transfer heat away from the board, otherwise it will create potentially damaging hot spots.
Important Aspects:
Thermal Conductivity: FR4 has a low thermal conductivity, typically around 0.3W, while for aluminum this varies between 0.5W-4.0W (most commonly preferred: around 1.0W).
Plated through hole (PTH): In MCPCB, there are no coated holes for single-layer PCB. Materials are usually placed on a single surface. The cost of PTH application is high, and it is not much preferred unless it is not necessarily required.
Solder Mask: PCB solder masks are usually dark colors. (green, blue, red, black.) It is usually applied on both surfaces. The MCPCB solder mask is almost completely white for LED boards. It is applied only to the surface where there is copper.
Thickness: General PCBs have a wide range of thicknesses using various combinations of materials and number of layers. MCPCB thickness variation is limited with the available backing plate thicknesses and dielectric layer thicknesses.
Preferred General Applications:
Lighting: LED Light is the main user of Aluminum PCB.
Power module: Power converters,
Power supply: Switching regulator, DC/AC converter, SW regulator,
Automobile: Electronic regulator, ignition, power controllers,
