One of the most visible challenges
test engineers face today is the increased complexity of the devices they need to test. For example, the consumer electronics, communications and semiconductor industries continue to drive the convergence of digital imaging/video, high-fidelity audio, wireless communications and Internet connectivity into a single product. The fluid functionality of these complex
devices is defined by the software embedded in them, which gives design engineers the ability to add features faster than ever before.
Next-generation test systems must be flexible enough to support the wide variety of tests that differ among convergent products and they must be scalable enough to accommodate a larger number of tests as new measurement functionality is required. Software-defined instrumentation is the essential differentiator for meeting this test challenge. The mainstream adoption of software-defined modular instruments in automated validation and production test applications is confirmation of this trend.
The functionality of a modular instrument is characterized through user-defined software residing on the host PC instead of on the instrument. The role of software in modular instrumentation cannot be overstated. With a software-defined modular instrumentation system, engineers can quickly adapt to changing test needs. Through software, they can program a modular instrumentation system to function as one user-defined instrument using built-in shared clocks and triggers. PXI, governed by the PXI Systems Alliance (PXISA) since its inception in 1997, is an example of a widely used software-defined instrumentation platform for building modular, automated test systems. The PXISA comprises more than 70 vendors, including Agilent Technologies, National Instruments and Rohde & Schwarz, as well as more than 1,500 software-defined PXI instruments.
Frost & Sullivan Measurement & Instrumentation Research Manager Kiran Unni recently stated, “The adoption of tools such as PXI is an indicator that companies recognize the benefits of moving toward software-defined instruments. The savings being realized in capital equipment, system development and improvements in system efficiency all contribute to reducing the per-unit cost of tests, directly influencing the bottom line.”
Engineers implementing test systems based on modular, software-defined instrumentation attain increased flexibility and performance compared to hardware-defined instrument systems from previous generations. For example, Microsoft needed a functional test system for its Xbox 360 controllers. Microsoft engineers were able to rapidly adapt the existing software-defined Xbox test system to meet the new test requirements including adding new PXI modular instruments. The new PXI tester resulted in a 100 percent increase in test throughput per test station.
As devices continue to become more complex and include more disparate technologies, test systems must become more flexible. The only way to accomplish this is through software-defined instrumentation, which helps engineers develop scalable, high-performance test systems.
Kevin Bisking is senior product manager for National Instruments.