A new era in space products: Radiation tolerant commercial space devices
Article By : T.J. Fure and Gabino Alonso, Analog Devices Inc.
The demand for innovation in space products has never been higher.
Recent developments have made doing business in space ever more achievable to a broadening base of companies. A market previously consisting solely of major defense contractors and national governments has been disrupted by a growing list of commercial companies determined to deploy an enterprise beyond the confines of our terrestrial home. This paradigm shift is also driving new developments in space products that will have a dramatic and exciting effect on spacecraft size and performance in the future for all customers.
Promising commercial companies fill the news with reports of huge investments in space technology. The cost of launch has dropped to the lowest level in history as companies develop new approaches to launch vehicles. Investments of up to $1B are going toward deploying constellations of low Earth orbit (LEO) satellites to connect people in remote corners of the globe. Other approaches to increasing internet connectivity include high altitude unmanned aerial vehicles (UAVs). These approaches require more integrated parts to build smaller, lighter platforms to achieve their goals.
Clearly, the demand for innovation in space products has never been higher. Analog Devices Inc. has a long history in the space business of delivering the highest quality, reliability, and resilience to the damaging effects of radiation in space. Our heritage line of space products is well known in the industry to be hardened to over 100 krad, making these products suitable for the harshest orbits.
Analog Devices is well known for developing new ICs for the commercial market that enable our customers to design smaller and more efficient products. However, transitioning these to space qualified products is complex and time-consuming. The vast majority of new ICs are built on BiCOMS processes that give us the capability to combine the best of bipolar and CMOS process technology. From a radiation tolerance perspective, though, these BiCOMS devices require us to characterize and mitigate effects of both total ionizing dose (TID) as well as single event effects (SEEs). This extends the development time for new products at a time when we need to release new products more rapidly.
Another factor driving new product development is packaging since many new products are being designed with unique packaging that enhances the performance of the commercial IC. In some cases, transitioning a commercial product to space becomes impractical when its performance is tied directly to the existing non-hermetic package. This might include issues related to additional parasitic effects that require complete new hermetic package development, costly redevelopment of post package trim, or procurement of new highly complex test systems and handlers. Whatever the issue, we offer existing commercial products that previously had no chance to transition to space products because the investment was too great to justify.
Figure 1: An example of a miniaturized satellite platform using PEMs.
Luckily, there are other forces at work that will allow us to develop more advanced products more rapidly. The first is that the total dose radiation requirements of LEO are lower than traditional orbits, so a product that can meet 30 krad to 50 krad tolerance is acceptable. The second is a ground swell of support for the use of flying plastic encapsulated modules (PEMs) in space, an idea that until recently had been met with outright disdain from EEE parts managers and engineers. It will not be easy, but if done properly and accepted by the space community, these developments will open the door to dramatic improvements in performance, as well as reductions in size, weight, and power (SWaP) for the spacecraft.
Producing space qualified PEMs with the highest quality and reliability is crucial to our combined success. The major space agencies around the world have long had specifications for the postprocessing of PEMs to qualify them for space use. The space community has long resisted the use of PEMs due to inherent risks and uncertainties in the process, including lot traceability, validity of radiation test results, test program correlation, and lack of manufacturer warranty and support. It is costly and time consuming to do the testing and carries the risk of a lot failure leaving the designer to start the process over with a different part, add shielding, or include other mitigation techniques that add cost and weight. If we as the manufacturer offer a space qualified PEMs product, those risks are greatly reduced. It also opens up the possibility to dramatically improve the build schedule as well if the product we are offering is in stock.
To address these needs, Analog Devices is introducing a new line of commercial space products. In this line, we will offer three distinct flows targeted at differing requirements from customers depending on the quantity of satellites they will be flying. The lowest flow is intended for pure commercial space customers looking to fly high volume in space, offering special support for radiation requirements. The medium level flow is an optimized flow offering additional radiation test, screening, and lot qualification. These flows will likely satisfy the vast majority of commercial space customers.
The high level flow combines improved quality and reliability screening and qualification with radiation characterization and assurance. The combined flow will include radiation characterization both for TID and SEE as well as lot qualification for TID. The work required is extensive and the unit pricing must reflect that. Even so, the benefits in performance, and reductions in size, weight, and power compared to existing space qualified products coupled with the quality and radiation assurance will more than justify the cost and will enable future spacecraft to deliver higher performance at a lower total cost than ever before.
We fully recognize that not every mission will be able to accept PEM products. So we will continue to develop similar advanced products for use in hermetic packages where those previously mentioned packaging challenges prove manageable. In order to focus our effort on the products that will truly transform your future spacecraft, we would appreciate hearing from you. Please let us know which Analog Devices products would most dramatically affect SWaP and performance for your spacecraft. It could be small reductions multiplied by many uses in a spacecraft or products that integrate many functions and protection features into a single component with few features. Our future product development will be driven in large part by customer demand.
Figure 2: ADI’s product life cycle.
For more information on any of the abovementioned products, visit analog.com/DAC.
About the Authors
T.J. Fure has over 25 years of experience in the semiconductor industry and over 10 years focused on the military and space market. His semiconductor knowledge includes water fabrication, assembly, test, qualification, failure analysis, and reliability. He also has experience in circuit design, applications engineering, sales, and marketing. His current focus is developing products for the space industry that will enable future spacecraft to achieve transformative capabilities that dramatically reduce size, weight, and power. He holds a Bachelor of Science in electrical engineering from Arizona State University. He can be reached at tyler.fure@analog.com.
Gabino Alonso is currently the marketing manager for the Power by Linear™ Group. Prior to joining ADI, Gabino held various positions in marketing, engineering, operations, and education at Linear Technology, Texas Instruments, California Polytechnic State University, and Cabrillo College. He holds a Master of Science degree in electrical and computer engineering from University of California, Santa Barbara. He can be reached at gabino.alonso@analog.com.
