PCB Blog - Military circuit board

Military PCB is a circuit board specifically designed for military purposes. In terms of design and manufacturing, this type of circuit board is more complex than ordinary circuits. Military PCBs must meet the requirements of the military industry. Circuit boards in military applications require high functionality and reliability. This is because they must withstand harsh environmental conditions.

Military PCB is a circuit board that meets military specifications and requirements. To produce military PCBs, all components must be of military specifications. The most important thing is that the tolerance of these components must be between 1% and 2%. Manufacturers must use circuit boards that can withstand the highest current load.

Standards and requirements for military circuit boards

1) MIL-PRF-31032

Basic performance specifications for printed circuit boards used in highly reliable military systems. It defines general requirements for materials, design, manufacturing, quality control, and testing. A single weapon system or project typically refers to MIL-PRF-31032 as a benchmark.

2) MIL-PRF-55110

General specifications for printed circuit boards and related materials used in military systems. It provides default requirements for various board types that can be further customized for specific applications.

3) IPC-6012

The IPC's Class 3 performance specifications provide additional baseline requirements for high-reliability PCBs beyond commercial grade. It is authorized for many defense projects

Notes on designing military circuit boards

1) Durable

Supports operation under shock, vibration, temperature cycling, and other environmental stresses. Strategies such as thicker copper layers, larger pad sizes and trace widths, and additional mechanical fastening points can increase durability.

2) Thermal management

High-power military systems require careful heat dissipation design to dissipate heat. Large copper planes/polygons, thermal conductive dielectrics, and thermal through-holes help with heat conduction.

3) Mixed signal circuit

Isolate sensitive analog signals from noisy digital circuits by partitioning, protecting wiring, grounding, and placing components.

The characteristics of military circuit boards

1) Climate resistance

This is a major feature of military circuit boards. These boards can withstand any weather conditions. They can withstand moisture and high temperatures. The use of additional shielding and thermal compounds helps with this feature.

2) Mil specification components

Military PCB manufacturers use military specification components when producing these boards. Military specification components provide enhanced durability, functionality, and reliability. Mil specification components have a stricter tolerance range between 1% and 2%.

3) Chemical corrosion resistance

This is one of the biggest characteristics of military polychlorinated biphenyls. These polychlorinated biphenyls can withstand any chemical attack. Military circuit boards have high chemical resistance. Therefore, they have less chance of being corroded.

Printed circuit boards used for military applications require specialized design and manufacturing to meet strict reliability and performance requirements. Unlike commercial PCBs, military circuit boards are constrained by strict quality standards for critical defense systems, where failures are inevitable.