By John Keller
Designers of high-reliability power integrated circuits say they are concentrating primarily on space power applications, rather than on the military, because many of even the most demanding military power applications these days can meet their environmental requirements with commercial off-the-shelf (COTS) power electronics.
“Our primary focus is on the space market in high rel,” says Richard Southwell, director of sales for the International Rectifier (IR) high-reliability products group in El Segundo, Calif. “Many commercial automotive-grade products can meet military requirements from a reliability standpoint.”
Military applications that require power components have been migrating to COTS power IC parts for the better part of the past two decades—particularly since the Pentagon formally moved in the direction of COTS in 1994.
“We are really focused on the satellite and space market, where there is more testing, radiation hardening, and extended temperature requirements,” says Ravi Pragasam, senior market manager for the National Semiconductor Corp. high-reliability group in Santa Clara, Calif.
When designers of power ICs manufacture devices for space power electronics, they primarily are concerned with requirements for radiation-hardened products that are able to resist the potentially harmful influence of naturally occurring space radiation, which can destroy components on orbit or shorten their life cycles.
“We reserve our internal development resources for space, because there is nothing on the commercial market that will meet the parameters for space, primarily because of radiation hardening,” says IR’s Southwell.
Make no mistake, military applications still require high-reliability power ICs, yet the strategy of manufacturers these days is to draw from their commercial-grade lines and make whatever changes might be necessary. “Very few hermetic products are used in the military today,” Southwell says. “Now it is all primarily enhanced plastic.”
Growing use of low-power design electronics in satellites and other space applications also is putting pressure on power integrated circuit designers. “One of the driving forces in these applications is the use of FPGAs and ASICs,” National’s Pragasam explains. “FPGAs are getting smaller in geometries, and voltages are smaller, so you need power solutions that support those. At the same time, they must support the longevity of the product.”
Many of power management IC requirements of commercial and military applications also hold true for space applications, Pragasam explains. “We see SWAP (size, weight, and power) as hugely important. Every time you launch into space, you need to be concerned with weight. Integration also is hugely, hugely important. The trend is to get the devices to be smaller, much more compact, and higher performance.”
The electronic architectures of satellites and other spacecraft also are changing with the times, and power management electronics architectures must change with them. “Our group is focused on space, and the biggest trend we see is distributed power,” Southwell says.
“Distributed power is a concept that has been embraced in the space industry,” Southwell continues. “Instead of one master power supply, there is a trend in the space industry to go with smaller, lightweight, more flexible power supplies that you can place right at the point of the load. You might have numerous smaller, lightweight power supplies. We put more and more of the power management and intelligence in the chip to reduce parts count, and make it small and low cost.”
