PXI has grown to become a viable instrumentation platform and in many cases, contender against VXI for demanding applications once thought to be out of reach due to limited channel density and performance. As PXI moves into more traditional test markets such as military ATE, new challenges will appear as a result of the environments in which these systems are deployed. As existing rugged PC, VXI, and proprietary platforms are replaced, these next-generation PXI systems must be capable of withstanding harsh environments. High shock and vibration, sub-zero temperatures, stringent EMI limits, condensing humidity, and excessive dust all combine to create a highly undesirable system environment. While the relative compact size of PXI is a benefit, survival in such conditions requires careful consideration at the chassis level. While some issues such as shock isolation and low-temperature control may be similar to those faced in the existing ATE design, many new challenges exist. As both a developer and manufacturer of PXI standard packaging and the largest provider of PXI OEM packaging, Tracewell Systems has the technologies in place to address these issues. Cooling is a primary challenge in these systems. While the PXI card size is small, component density is typically very high making it difficult to provide sufficient cooling. This is often a problem even in commercial applications running at near room temperature; field ATE systems are often faced with operating temperatures approaching 50 deg C. Although the PXI standard limits the amount of power per slot, adaptations not unlike in VXI implementations will no doubt push power dissipation well past recommended limits. Successful cooling of systems in such an environment will require the use of advanced cooling methods such as Tracewell's Advanced Vector Controlled Airflow (AVCAF). Power requirements in 3U PXI systems are often equal to power requirements in 6U VXI systems. Power supply size and efficiency are both important considerations for both the PXI system and the unit under test. Tracewell Power has introduced the TTX Series of power supplies, utilizing a patented power topology resulting in efficiencies near 90 percent meaning less heat loss and higher reliability. As a rugged, low-cost, and adaptive PC-based test architecture, PXI will continue to gain strength in the military ATE market.
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