The Differences Between Military and Civilian PCBs
Printed circuit boards, or PCBs, have become a technological standard in virtually every industry from mining to traffic control. Many of these industries use similar PCBs that adhere to the same set of manufacturing standards with little to no variation.
However, sensitive, precise, and complex industries such as aerospace travel, government data control, and military applications require higher PCB performance and fabrication standards.
Many of these industries have their own PCB regulations to ensure a safe and secure final product. You can learn about some of the regulations specific to government PCBs in our previous blog, “NIST 800-171 Compliance, PCBs, and Your Company.”
In this blog, we discuss the primary distinctions between military and defense PCBs versus strictly civilian PCBs, as well as how these differences may affect the engineering and manufacturing process for your company.
While all PCBs must perform under a range of conditions, military PCBs should be suited for the rigors of defense applications. Military PCBs may see more extended periods of use, extreme temperatures or climates, higher electrical demand, and other difficult conditions that don’t occur in typical commercial and industrial settings.
For example, military PCBs can be found in underwater craft navigational systems, large power arrays, missile guidance and launch systems, explosives testing systems, and communication devices intended for critical and sensitive field use.
Military PCBs must be designed, manufactured, and stress tested to ensure that they withstand:
- Demand for signal transmission strength and clarity
- High electrical amperage
- The presence of multiple ambient waveforms and frequencies without any feedback that affects performance
- Thermal duress
- Variable humidity
These capability requirements can be considered the fundamental reason why you would never commission military-grade PCBs from a manufacturer that typically supplies commercial-grade boards. Commercial components are not adequate for defense conditions.
In addition to the components themselves, military PCB manufacturers utilize different layouts to achieve more durable boards and more in-depth testing to predict how the board will perform in its final application.
The correct layout for a military board depends on the exact application. The layout requirements for an LED light array is less complex than that of firearms testing equipment. As you create your defense product, discuss the advantages and drawbacks of PCB layout options with your designer.
All military PCBs must undergo rigorous testing before being put into wide use. This testing is commonly known as design for manufacturability, or DFM, testing. Your manufacturer will test for basic performance as well as the essential characteristics listed above.
ITAR and MIL-PRF-31032 Standards
All technology used in the defense field must comply with strict standards that regulate the manufacturing, import, and export. The primary regulations that apply to PCBs ITAR and MIL-PRF-31032.
International Traffic in Arms Regulations, or ITAR, authorization is intended to manage the import and export of American defense and defense-related products. ITAR applies to 21 item categories, many of which involve PCB technology.
To receive ITAR authorization, companies register and then comply with established standards that make them subject to oversight from officials. ITAR authorization ensures that physical and intellectual property created for military purposes is secure at every stage of its production.
You can learn more about ITAR in our previous blog, “ITAR Authorization and PCB Development.”
MIL-PRF-31032 is one of the strictest sets of standards that can apply to a PCB. These standards regulate materials, layout, manufacturing, and so on. Many individuals confuse MIL-PRF-31032 and IPC 6012 3A standards when looking at PCB manufacturer qualifications.
This confusion comes from the fact that IPC 6012 standards divide PCB quality control into three classes and Class Three PCBs, designated as IPC 6012 3A boards, are almost exclusively used in military and aerospace applications.
However, MIL-PRF-31032 standards go a step further than IPC 6012 to establish guidelines tailored to the capability requirements discussed in the first section.
Check that your prospective PCB manufacturer has all relevant certifications and registrations without any violations before commissioning any military-grade boards.
For example, many manufacturers with MIL-PRF-31032 certification will also have IPC 6012 certification, but if your prospective manufacturer does not have MIL-PRF-31032, the final product may not be suitable for defense applications.
When you work in the military, other defense industries, or adjacent fields, you understand the critical importance of adhering to the highest standards in technology, manufacturing, and innovation. When you update an existing PCB or create a new product involving PCBs, keep the specifications for military PCBs outlined above in mind.
For the best results in your military PCB applications, partner with PCB engineers with a long track record of creating high-performance, secure, and compliant PCBs. These professionals can help you ensure that you retain your defense contracts and protect those who use your technology while serving their country.
For expert PCB design and creation with extensive knowledge of the distinctions between military and civilian applications, trust Streamline Circuits.