PC-104 single-board computers suitable for military applications

PC-104 format for single-board computers may seem old-fashioned and may be replaced by COM Express, but there are many manufacturers of them and many COTS (commercial off-the-shelf) military uses for them. PC/104 boards are available in hundreds of flavors from dozens of manufacturers around the world. No matter what you need, you're likely to find it in a PC/104 module. And all of these boards work together, so your system comes together fast. If you need additional functionality at a later date, just add another board to the stack. The stackable format cards are PC-based — like x86 processors and associated software. And they are relatively low in cost.

For military apps, these boards do need to meet temperature, shock, and vibration specifications, and they have long-term availability. I uncovered just a few of many such boards coming from at least a dozen manufacturers.

Diamond Systems

Diamond Systems’ Athena III PC/104 single SBC features a 1.0-GHz Intel Atom E640T CPU, 1 Gbyte of soldered-on DDR2 DRAM, a Gigabit Ethernet port, and a data acquisition system. It can meet IEC68-2-27 shock specification and MIL-STD-810E 514.4 vibration specs and has a −40°C to 80°C operating temperature range. The boards data acquisition includes a 16-channel 16-bit A/D with 150-kHz sample rate and four 12-bit D/A channels.

As an example application, we can look at a weapons station control system that was done by a European military equipment manufacturer and provided to the U.S. Army’s vehicle program. The unit controls a gunnery system from inside a moving military vehicle, which is often traveling over rough terrain. The manufacturer selected a custom variation of the Athena II SBC as the control processor. The SBC needed to be small and have full analog, digital, and serial I/O with excellent analog calibration accuracy and a graphical display interface.

The customer took advantage of Diamond Systems ruggedization program that added conformal coating of the SBC and flash disk. The gunnery system also is exposed to a relatively large amount of shock and vibration, and the SBC had to pass MIL-STD-810E 514.4 vibration tests. To successfully meet the specification, Diamond replaced all standard connectors with latching versions that had increased contact plating. In addition, the PC/104 connector, due to potential vibration wear between the mated contacts, was replaced by a high-reliability MIL style connector. All of the setup jumpers were replaced with soldered zero-Ω resistors and, to counteract the effects of extreme vibration over and above that of the MIL-STD-810, all of the BGA chips were under-filled to eliminate any solder bond cracking between the board and the BGA lands. Diamond has since updated the SBC to the Athena III version (backward-compatible). The Athena III PC/104 SBC comes in a variety of models beginning at less than $750 in volume.

Versalogic

The Cougar VL-EPM-14 from Versalogic is in the PC/104-Plus  form factor and uses the 500-MHz AMD Geode LX 800 Processor. The card takes less than 5 W and has 256 Gbytes of DDR memory, soldered in, plus a compact flash socket. It is tested to these shock and vibration specifications:

Vibration, Sinusoidal Sweep        MIL-STD-202G, Method 204, Modified Condition A

Vibration, Random                      MIL-STD-202G, Method 214A, Condition A

Mechanical Shock                        MIL-STD-202G, Method 213B, Condition J

The VL-EPM-14 has 10/100 Ethernet, four USB 2.0 ports, RS-232, RS-485, and an IDE port. It features high-performance video at up to 1600 x 1200 with analog and LVDS interfaces. This card is priced at $649 ea/10.

Advantech

The PCM-3363Z2-1GS6A1E from Advantech offers an Atom N455 single-core 1.66-GHz CPU and 1 Gbyte of DDR3 RAM. The board is “HALT tested and has 100% locked connector” for increased reliability, and it operates over −40°C ~ 85°C (PCM-3363Z2-1GS6A1E version only).

The card has an 18-/24-bit VGA output, Gigabit Ethernet, four USB 2.0 ports, RS232/485, a CompactFlash socket (Type I/II), high-definition audio, and a SATA 3 Gbit/s interface. Power consumption is only 7.0 W typical, 11.8 W maximum. Priced at $500.57 ea/10.