When I was just a little younger than I am now, I used to watch The Jetsons, a show about a family living in space, with amazement. Of course, watching how their lives were different from mine here on earth was interesting, but I was greatly fascinated by the fact that they drove around in space and there were rarely any accidents. This puzzled me for a while, as there are constantly accidents here on Earth. I finally postulated that they must have become better drivers, which was a necessary adaptation for the space environment. The need to adapt, especially for functioning in space, is not limited to safer driving.
Communications satellite in orbit
Probably, the most fundamental and yet the most critical capability we need as we increase our presence in space is the ability to communicate reliably. We have certainly mastered communication between space vehicles, such as satellites, and the Earth, which is evidenced by the global positioning system (GPS) that virtually all of us interact with daily. This achievement would not have been possible without adapting the way PCBs and electronics that comprise the communications systems of space vehicles were built. Let’s explore the process of aerospace PCB manufacturing for communications, but first, let’s define the boards that are used for communicating in space.
What Are Communications Aerospace PCBs?
Typical spaceship communications system
In the figure above, a spaceship internal communications system is shown. As illustrated, onboard communications occur between all major systems, primarily for monitoring and control. The boards perform the communications activities are communications aerospace PCBs. This includes boards that may also perform other functions.
These communications PCBs being in space present significant challenges for your board’s manufacturer. A major challenge is signal integrity on the board and between systems where radiation may be present. In most cases, this means high-speed materials and other special considerations, such as high-density interconnects (HDI). For some boards, especially involving thermal and propulsion subsystems, thermal issues are very important. For others that may be exposed to vibration, mechanical stress or require flexibility, structural integrity is a prime concern. In order to address these considerations for communications aerospace PCB manufacturing, your contract manufacturer (CM) may need to apply several solutions. Let’s see what the options are.
Communications Aerospace PCB Manufacturing
CMs that build PCBs for critical systems, including medical devices and automotive, must address a number of considerable challenges. For aerospace systems, a good deal of these are regulatory requirements. When it comes to confronting the manufacturing concerns for aerospace communications PCBs, CMs are largely guided by their expertise and best practice techniques, such as those listed below.
Aerospace PCB manufacturing techniques for best communications
- Use smaller components
Surface area is always at a premium on space platforms, and smaller components are less susceptible to radiation, which can disrupt signal transfer on the board itself as well as communications with remote electronics. This means weighing SMT versus through-hole technology to reduce board size while providing adequate spacing between components to minimize EMI.
- Use rad-hard components
Another means of ensuring communications in space is radiation hardening. In fact, for high energy ionizing radiation, which can in some cases prevent communications boards from operating at all, hardening components and electronics packaging is the only effective means of protection. However, this method will likely add weight and size to your boards.
- Increase solder paste
Mechanical shock and vibrations are not limited to the space vehicle structure. On-board electronics and boards are also subject to these stresses. Using increased solder paste volume during assembly can yield better solder joint quality and ensure that communications board components maintain reliable connections which support good signal transmission and reception.
- Use PCB pins
The use of PCB pins to secure board connections can be helpful in securing components against vibrations aboard space vehicles and also help signal propagation as it provides the consistency of a plated through-hole (PTH). Note, this will add to PCB manufacturing time (and perhaps cost); therefore, its usage must be weighed against these factors for the specific case.
- Use conformal coating
Conformal coating can increase board reliability when exposed to temperature swings that are prevalent in space. It also protects the paths for communications signals against moisture and other debris.
|Tempo‘s Custom Avionics for PCB Manufacturing Service|
By utilizing the techniques listed above, your CM can maximize the reliability of your aerospace vehicle communications. At Tempo Automation, the industry leader in fast, high-quality PCB prototype and low volume manufacturing, we have the expertise to build your aerospace communication boards to meet your communications requirements.
And to help you get started on the best path, we furnish information for your DFM checks and enable you to easily view and download DRC files. If you’re an Altium Designer or Cadence Allegro user, you can simply add these files to your PCB design software. For Mentor Pads or other design packages, we furnish DRC information in other CAD formats and Excel.