The Use of Heavy Copper in PCB Design and Fabrication
The use of heavy copper PCB has had revolutionary experiences over the years. Being an efficient and reliable PCB material for designing most electronic circuits; Heavy copper is undoubtedly gaining popularity in most industrial and technological applications. Unlike the traditionally printed circuits, heavy copper PCB can withstand high current ratings hence boosting productivity. While this technology can be a bit costly, the wide range of applications, efficiency and advantages are worth the investment.
Heavy copper fabrications are designed using a copper material in a weight range of 4 oz./ft2 to 20 oz./ft2. This design can efficiently conduct heat away from the electronic components reducing overheating issues and thermal failures. heavy copper PCB is available either double-sided or multi-layered. They are usually manufactured using a specific number (depending on its application) of copper foil sheets. The etching process follows to get rid of unwanted copper parts. Plating is then done to sides, planes, and traces through holes and the circuit is laminated into a final product. High-speed plating and differential etching are the special techniques used in the design process.
Why Heavy Copper?
As earlier stated, heavy copper is used for high current applications due to their ability to withstand high-temperature ratings. Temperature is one of the main determinants of how much current an electronic device can carry. Due to the ohmic resistance in the circuit, there will be power loss as current passes through the traces; this generates heat in the PCB circuitry. To avoid damage to the various components, the copper trace supplies heat to the neighboring materials through conduction. This heat is then transmitted out of the PCB board through convection. Apart from thermal management, here are the other advantages of heavy copper PCBs.
- Increased mechanical strength at the connector sites
- Ability to create smaller product sizes by using multiple weights on one circuitry layer.
- Ability to use exotic materials to a maximum capacity with minimal risks of failures.
- Better current conductivity and ability to survive repeated thermal cycling
The pioneering applications of heavy copper were in power electronic devices used in Aerospace and Military applications. Their uses include; weapon control systems, power distribution panels, power supply for radar systems, battery charging systems & even monitoring systems. The preference was due to their advantage of withstanding more current without necessarily creating excessive power losses via localized heating. Advanced circuits that offer heavy copper capabilities are sometimes referred to as Extreme copper and they weigh between 20oz/ft2 to 200oz/ft2
Nowadays, the use of Heavy copper is gaining popularity as a technology of choice for most industrial applications. Except for low voltage applications, the use of heavy copper PCBs is inevitable. Heavy project designs, for example; driving high current transistors and resistors make use of heavy copper to increase efficiency.