Why Use Heavy Copper PCBs?

The goal of any printed circuit board project is to design it correctly from the start since modifications can prove costly and push back your timeline. A heavy copper PCB is no exception.

Certain printed circuit boards are designed to produce more amperage (or the strength of the electrical current) through the trace. But the higher the power requirement, the thicker the copper you need in order to transmit the signal through the board. That is why heavy copper PCBs are used in higher amperage designs.


What Is a Heavy Copper Printed Circuit Board?

A heavy copper PCB contains at least one ounce of copper, and the amount can increase in one-ounce increments. These types of circuit boards, however, are not as common as standard PCBs; about 20% of all printed circuit board projects are heavy copper.

A standard printed circuit board, contains up to one ounce of copper.

What Is a Heavy Copper Printed Circuit Board?

Applications for Heavy Copper PCBs

Heavy copper is often used in high energy (or high current) printed circuit boards, specifically power electronic devices and power supply systems. These type of PCBs are found most often in the following industries:

  • Industrial
  • Military
  • Oil
  • Solar energy
  • Aerospace
  • Computer

There are no applications where heavy copper couldn’t be used, but it’s important to remember that the amount of copper in a project is driven by the demand of the design.

Heavy Copper PCB Construction

Standard PCBs are fabricated using standard copper etching and plating processes. Heavy copper PCBs have a similar construction, but dielectric separation is generally greater with heavier copper. Dielectric separation is the nonconductive substrate between the copper layers

Heavy Copper PCB Construction

Benefits of Heavy Copper PCBs

Why should you opt for a heavy copper PCB? Here are some of the benefits:

  • Heavy copper PCB provides increased current carrying capacity.
  • You’re looking for a PCB that can withstand the shock and vibration of a particular environment.
  • Heavy copper also conducts heat out to the edges of the board, thus increasing performance.

Heavy Copper Carrying Capacities

How much current can a heavy copper PCB carry? The answer depends on the amount of heat a printed circuit board can withstand. In order to determine the maximum current, you must first estimate the heat rise that’s connected to the applied current.

Heavy Copper Carrying Capacities

Cirexx’s Heavy Copper PCB Capabilities

Design & Test
Minimum 5-7 mil trace width, 6 mil air gap starting with 2oz Cu, and larger traces and air gaps as the weight of the copper increases incrementally. IPC class 2/IPC class 3
Drill & Rout
Counter sinks/counter bores, Scoring/rout and retain, Laser route, Blind vias/buried vias, Stacked vias
1-30 layers, Vacuum lamination, Sequential lamination
Conductive via fill, Non-conductive via fill, Plated edges, Plated radii (castellation), Plated milling cutouts, Hard gold body, Soft bondable gold, Immersion gold, Immersion silver, HAL standard, HAL lead-free (ROHS), ENTEK (OSP)
Flex and rigid-flex, Kapton™ , Rigid RF and high-speed materials, Hybrid Mix /FR-4-Teflon, Metal back boards (LED/power distribution ), Heavy Cu 6 oz. finish rigid substrates

Cirexx has the technology, deep engineering experience, and knowledge to help you design and build a heavy copper PCB correctly from the start. With our innovative capabilities, we can fabricate a PCB with up to 6 ounces of copper for outer layers and up to 4 ounces for inner layers. If you have questions about how much copper you need for your project, contact us, and we’ll get back to you shortly.

Looking for a Heavy Copper PCB Quote?

We use a well-organized process and the right software to provide you with a quote within 24 hours. After you upload your information, including any fabrication drawings or schematics, our engineering staff will analyze the data and provide us with a comprehensive document so we can take a closer look at your heavy copper PCB project.

Looking for a Heavy Copper PCB Quote?

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