Table of Contents
What is Heavy Copper PCB?
Advantages of Heavy Copper PCB
Higher Currents Handling
Better Heat Dissipation
Extended lifespan
Design Considerations of Heavy Copper PCB
Copper Thickness
As a clearer picture of how copper thickness plays out to the design below is the following table that illustrates the copper thickness to minimum trace width and maximum current capacity. The figures in this table are general guidelines that engineers use to determine how wide the traces should be for a given copper thickness to safely carry a specific amount of current:
|
Copper Thickness (oz/ft²) |
Minimum Trace Width (mm) |
Maximum Current Capacity (Amps) |
|
4 oz |
1.5 |
10 |
|
6 oz |
2.0 |
15 |
|
10 oz |
3.0 |
25 |
|
20 oz |
5.0 |
50 |
As shown in the table, a 4 oz copper layer requires a minimum trace width of 1.5 mm to handle 10 amps, while a much thicker 20 oz layer needs a 5.0 mm wide trace to safely carry 50 amps. This example highlights how critical it is to adjust trace widths based on the copper thickness to ensure the board operates efficiently and safely under high-power conditions.
Thermal Management
In high power electronic applications, thick copper pcbs experience high operational temperatures because of the large currents they conduct. Of particular note, these boards have multiple copper layers which can inherently help to dissipate heat but it is not enough to prevent high temperatures from arising. Other measures are required to help the PCB run optimally and safely and without getting too hot, or otherwise getting damaged.
Thermal Vias
Heat flow can be well controlled in a heavy copper PCB, one of the best ways being through the use of thermal vias. These are small Through Holes that are made from copper in the PCB; they function to transfer heat from high power density areas such as power components to other dissimilar planes or layers or even to a heat sink. Defining heat away from delicate items, the thermal vias do not allow the single points to become too hot and, instead, dissipate the heat far better around the copper.
Heat Sinks and Pads
The insertion of heat sinks or thermal pads is another vital part of agendas when it comes to thermal issues. Heat sinks are metallic pieces which mechanically mounted to the outer layer of the PCB to transfer heat away from devices such as power transistors or voltage regulators. Heating films, however, are typically located under such parts for better heat dissipation to the PCB or an external cooler. Altogether they will guarantee that the important components are at their permissible operational temperature even at increased electrical load.
Plating and Etching
The process or fabrication of heavy copper PCBs is slightly different from those of ordinary PCBs with simple copper shapes. Thick copper foils demand aggressive approaches to etching to create small features without under-etching the traces. In most cases, several cycles of plating are required to provide the needed thickness of copper on the component.
- Plating: Dense copper layouts can call for several etching cycles to deposit the appropriate thickness of copper.
- Etching: Vintage techniques in etching are required to make clean traces, mainly because copper thickness makes etching harder.
Via Design
Vias are essential in any PCB, but in heavy copper designs, their ability to carry current and dissipate heat becomes even more critical. Larger or multiple vias are often necessary to handle the increased electrical and thermal loads.
Mechanical Strength
Heavily copper PCBs are manufactured to take demanding situations including mechanical shock, vibrations as well as fluctuations in temperatures. The thickness of copper layers in a layered board will always make the board strong, but one should still pay a lot of attention while designing the board so that the components do not move or get damaged while in use.
However, in regions of the PCB, where the circuit might be subjected to physical stressing such as bending or vibration, then the conductor traces should be wider and thicker. This helps guard against the vias and traces from cracking or getting damaged in the future, thus making sure the board is still dependable even where the environment is quite destructive.
Housings that can be physically stressed during operation, for example, power components or connectors, require solder joints with larger cross-sections. This makes certain that the component interconnections stay correctly soldered on the PCB, especially in times when there are rigorous and obtained conditions such as vibrations or mechanical shocks. Subsequently, it should be noted to properly pitch and reinforce key regions of the board, heavy copper PCB can be reliable mechanically as well as would endure dynamic campaigns.
Application of Heavy Copper PCB
Heavy copper-based PCBs are used in applications that call for increased power carrying capacity and ability to withstand harsh conditions of high temperatures, vibrations, amongst others. Here are some of the common industries where they are used:
Power Electronics
High copper PCBs are used in power supplies, inverters, and converters because control of large currents and the ability to efficiently shed heat are significant factors necessary for the functionality and reliability of PCBs.
Automotive Industry
Solar Power and Renewable Energy
Such PCBs are employed in solar power systems as well as in the controllers and inverters in solar panels where the capacity to manage current and dissipate heat in a proficient and effective manner.
Industrial Control Systems
Military and Aerospace
It remains ideal for defence and aerospace industries because they offer excellent performance under varying harsh environmental conditions and currents required in the sector coupled with mechanical stresses ripped out from the two industries.






