The PXI-based instrumentation market is the fastest-growing segment in the automated electronic test market
PXI, PCI eXtensions for Instrumentation, has emerged as a major force in the test equipment and instrumentation industry. PXI provides a rugged PC based platform for use in automated test, data acquisition and many other applications.
It successfully combines rugged mechanical elements with a high electrical performance specification and a low cost. Using standard PC technology, this makes PXI an ideal platform for a host of applications.
Peripheral component interconnect (PCI) extensions for Instrumentation (PXI) is an open modular standard in the automated test and measurement. It offers high measurement speed, small footprint, and low power consumption compare to traditional test and measurement technique such as rack-and-stack test systems. The various application market of PXI technology include, wireless technology, aerospace, defense and consumer electronics industries.
On the basis of the various end user applications, the global PXI market can be segmented in five different classes namely, wireless communication or RF, aerospace, defense, consumer electronics and other. Wireless communication segment holds the majority of market share and still showing promising growth aspects in coming years. PXI module is very popular in wireless communications technology particularly in PXI-based platforms to assist complex and challenging test requirements for radio frequency (RF) in wireless communication.
PXI testing is more precise and accurate compare to other traditional test and measurement technology. Additionally PXI software and hardware suppliers are also designing their equipments with in-built feasibility for new testing methods which offers easy switching option to engineers. Moreover shifting of traditional box test and measurement technology towards more advanced and accurate technology is driving the global PXI market.
PXI is relatively new test and measurement technology. It requires proper skill and training which is not well known to the older generation of engineers and hence acting as a challenge for the overall adoption of the PXI market. However the effect of this is expected to minimize in upcoming years especially with new generation of engineers with more skill on computer based tools and technique.
PXI is an ideal deployment platform for measurement and automated test systems, environments in which reliability is critical. As devices become more advanced, it increases the amount of necessary testing. Rising costs are thus associated with validating these new products. PXI was created to specifically address the challenges in the automated test industry. In comparison with traditional box instruments, PXI-based test setups can be customized with the instrumentation modules needed to meet each new test requirement. They provide complex test setups while retaining flexibility.
Next-generation devices have prompted suppliers of PXI-based test products to provide complete test solutions to meet the complex testing requirements of these devices. By combining modular PXI-based hardware with measurement software, these test solutions provide comprehensive results with benefits in test time and cost.
Some of the leading companies operating in global PXI market include, ADLINK, Aeroflex, Keysight, LitePoint, ZTEC Instruments, Marvin Test Solutions, Modular Methods, National Instruments, Pickering Interfaces, Teradyne, and VTI Instruments.
PXI strengths in Automated Test discussed by Bob Stasonis – Sales & Marketing Director for Pickering Interfaces
Automated test today is highly modular in nature. While there are some areas of test that require large stand-alone instrumentation (Millimeter Wave Technology applications come to mind), that barrier for modular test is dropping. When PXI first started, a few MHz was the best you could expect to measure – now 50 GHz is achievable.
The industry of course has to deal with increased RF Bandwidth, complex waveform capture and generation, as well as increased functionality of each PCB. But the industry also has to deal with the reduced individual value of each module tested. By that I mean, how much can we afford to test? For one example, look at the cellphone industry – their cost of test is probably half of what it was 5 years ago, yet the complexity had gone up exponentially. If one were to look at the test strategy of a smart phone, I would believe that the most complex testing is in the lab and NPI (New Product Introduction). In volume production, it can be as simple as “Does the device turn on? Then ship it!”
For the most part, the challenges in automated test are the same as in the past – the balancing act between budgets, test times, specifications, and first pass yield. What is changing depends on the application – bandwidth, complex modulation schemes, and high speed serial busses do present problems for the test engineer. But generally speaking, as I mentioned in an earlier answer, a bigger issue may be that many products have such a low build cost that there is very little rework budgeted for. If it fails, bin it. Or do we test at all because we can’t afford the added expense? The trend in low cost electronics is to get the manufacturing process right as soon as possible and minimize potential failures.
Modular platforms are desirable for many reasons – small footprint, common chassis for many instrument types, tightly coupled triggering schemes, and cost. While there are still some automated applications that are essentially “do it yourself”, they are few and far between.
There are several modular platforms for automated test. At present PXI is king. VXI, which has been around since the late 1980’s is now primarily for legacy applications. While there are a few new modules introduced by VXI manufacturers, they are not addressing the newer manufacturing challenges.
In addition to PXI, a newer modular platform called AXIe is starting to get attention. AXIe has the same PCIe fabric and programming as PXI, but with multiple configurations for minimal rack space as well as substantial PCB Real estate and power densities compared to PXI for large, complex applications. So far most AXIe applications I have seen are related to Semiconductor test – also there are very few AXIe products at this time. But there are more than ten companies who are members, so I would not be surprised to see more AXIe in the future.
PXI has evolved to meet the speed and complexity of so many applications. The latest generation of PXIe features us to 8 GB/s data rates per module for very complex waveform generation and acquisition. Members of the PXI Systems Alliance have expanded the bandwidth of PXI instruments to measure up to 50 GHz. The fact that PXI Express chassis support legacy non PXIe modules in hybrid slots means that no instrument or switching is obsolete. PXI is able to support legacy applications as well as new ones, often in the same chassis.
ince 1998, Pickering Interfaces had been very focused on signal switching and sensor emulation. We have been involved in PXI almost since the beginning or PXI. In the past 18 years, we have designed and built a catalog of over 1,000 PXI Modules. We offer a breadth of choices ranging from DC to fiber optic switching, including the highest density matrices on the market, the highest switching voltage (1,000 V) available in PXI, Microwave switching up to 65 GHZ, and the broadest range of modules for simulating resistive sensors, RTD probes, and strain gauges. With a 3 year warranty and offices and agents around the world, we have the products and the support to serve our customer’s needs.
Satish Mohanram, Technical Marketing Manager, National Instrument highlights the level of innovation in PXI platform
One of the largest operational costs associated with automated test systems, especially in the aerospace and defense industry, is the support and maintenance cost over the life of the system. Proactive life-cycle management requires designing maintainable testers, diligently monitoring automated test equipment (ATE), and tracking instrument and component end-of-life (EOL) notifications.
While life-cycle management might not be a novel concept, the reality is that the evolution of mobile technology, accelerated hardware obsolescence, and sheer volume of test software are making this task increasingly difficult. Best-in-class organizations are rearchitecting test strategies to gain a competitive advantage amid the growing challenge of life- cycle management. Evolution of OS Life Cycles Within a decade, OS providers have transitioned from releasing a single OS and maintaining it for several years, such as Microsoft Windows XP (which was supported for 13 years), to today’s paradigm that targets mobile users that expect constant upgrades. This requires OS providers to frantically release new versions and retroactively fix bugs in daily updates. Global market intelligence firm IDC forecasts that smartphones and tablets will control 88.4 percent of the smart-connected device market by 2019, leaving portable and desktop PCs with only 11.6 percent. As mobile devices control vast majority of the market, OS providers will continue to prioritize the mobile user. This shift poses a monumental hurdle for test systems that rely on a stable OS to eliminate the need for system revalidation. As a result, some organizations are moving to Linux-based systems to have more control over the OS. Another approach is to minimize the number of OSs to reduce the burden for test engineering and IT organizations. Many legacy test systems contain several OSs (one for each unique box instrument), which introduces the risk of revalidation due to individual OS updates.
One major benefit of modular platforms, such as VXI or PXI, is the single OS controlling all instruments in the chassis or system.
Accelerated Decay of VXI and Legacy Instruments
In the late 1980s and early 1990s, the aerospace and defense community standardized on VXI as the modular commercial off-the-shelf platform for ATE systems. However, as VXI grows obsolete and support diminishes for legacy instruments, programs are under increased pressure to migrate to a stable alternative. This is compounded by a looming RoHS conversion deadline, which will increase the rate of component and instrument EOLs.
Over the past decade, PXI has replaced VXI as the de facto modular platform for ATE systems due to the size, performance, cost, and level of innovation in the platform. Global consulting firm Frost & Sullivan expects PXI to grow by 17.6 percent annually, which accounts for most of the expected growth for the test and measurement industry. With nearly 70 vendors offering more than 1,500 PXI instruments and a steady stream of innovation, PXI will continue to provide increased value to long-life-cycle ATE systems.
As teams migrate from VXI-based to PXI-based test systems, the investment required to modernize hardware will typically pale in comparison to that of updating and revalidating software. Due to the criticality of the system and the tight regulations for requirements tracking and software validation, simply opening, saving, and revalidating a test program set (TPS), or test sequence, can cost hundreds of thousands of dollars. This has created an environment where companies must rethink their software strategies or risk hemorrhaging money to sustain legacy testers.
Since minor software changes can greatly impact TPS compatibility, instrument vendors should offer TPS-compatible hardware migration options. This includes preserving driver functionality, APIs, and dependencies between driver versions to minimize the impact on the hardware abstraction layer. For example, NI is collaborating with Astronics Corporation to bring remaining VXI instruments into the PXI platform, such as the Astronics PXIe-2461 frequency time interval counter, which preserves TPS compatibility with legacy systems. Despite their best efforts, vendors cannot always provide TPS-compatible alternatives. In these situations, a common approach is emulating legacy instrument functionality. Recently, engineers have adopted software-designed instruments with user programmable FPGAs to augment standard instrument capabilities with custom functionality to emulate legacy behavior. For example, filters and triggers that were common in instruments 20 years ago and obsolete in today’s instruments can be reengineered.
To maintain margins while the average sales price shrinks, companies must reduce the cost of semiconductor design and test. Given that test cost is often nearly half of the cost of goods sold, according to IC Insights, RFIC suppliers have a renewed focus on decreasing the cost of manufacturing test. Over the past decade, this intense focus has produced a significant shift from using turnkey ATE solutions to building in-house and cost-optimized testers based on off-the-shelf instrumentation. The ability to specify a tester for a specific IC device—along with improvements in instrumentation technology—can significantly reduce test cost. This shift to a custom tester approach has been a large factor in the success of modular instrumentation platforms like PXI in manufacturing particularly because modular instruments have shown excellent value per performance.
Today, PXI instruments offer the measurement accuracy required for R&D and the speed required for manufacturing test. As a result, organizations are increasingly standardizing on modular instrument platforms throughout the entire design cycle, which directly reduces the cost associated with correlating measurement results. In addition to the improved speed and measurement quality of PXI, application-specific systems, such as the NI Semiconductor Test System, build on the PXI platform by adding a rugged enclosure, fixturing, DUT control, and the turnkey software required for the semiconductor manufacturing environment.
Testing such functionally integrated devices poses new questions. Do these become single modules that support all bands in one package? What test points will be exposed for functional test? Will these modules be tested at all bands on one station, or will they separate sub 6 GHz test and 60 GHz test? Modular platforms like PXI mitigate these scalability challenges by simplifying new I/O insertion that can augment existing functionality. In addition, traditional single-standard systems, which commonly incorporate LAN buses, do not scale to handle larger waveform sizes limited by data movement and processing power. For example, a typical 802.11ad signal requires up to 50X the data movement capacity as a typical 802.11ac signal. Unlike traditional systems that quickly grow in size and cost, modular test platforms like PXI provide a well balanced combination of size, cost, and I/O to support functionally integrated applications. PXI can handle nearly 16 GB/s of throughput today, and, as the underlying bus and processing technologies continue to evolve, it seems to be the logical test platform for future test technologies.
Sadaf Siddiqui, Business Development Manager, Keysight Technologies India Pvt. Ltd. explains how PXI allows engineers to build the test system they need today
The term, test system, represents millions of different possible configurations of test instruments, software, and device under test (DUT) specific test execution programs. Each test system is created based on a specific technology, application, and phase of a product under test development whether it is in research, validation, verification or manufacturing. Some test systems are created for consumer products such as smartphones and tablets and maintain goals of fast throughput, low cost, and easy to configure and update. Others such as satellite payload test, cost several million dollars to manufacture, are complex and must provide high quality measurements to ensure functionality, accuracy and repeatability of the payload while in orbit. With these examples and the endless possibilities for test systems in between, one type of test system cannot provide the answer for all test needs. When it comes to test system development, one size does not fit all.
Some of the other challenges can be integration with existing platform, adaptability for emerging standards, variation in test requirements, non-availability of custom accessories/fixtures etc.
High volume device test in manufacturing benefits from the use of modular instruments programmed for automatic measurement sequences where stimulus can be adjusted and results monitored through software. Multiple devices may be tested simultaneously and are best addressed by a modular system with a greater number of stimulus and measurement channels.
Modular instruments, such as PXI and AXIe, are becoming more widely used in test systems for several reasons. PXI and AXIe platforms address the engineers’ demand for greater measurement speed, including data transfers and synchronization across instrument modules. PXI is able to provide more functionality, stimulus input and measurement outputs, with more channels in a smaller form factor than benchtop instruments.
The PXIe chassis backplane is based on the computer standard PCI Express® (PCIe)® architecture and takes advantage of embedding this widely used leading edge technology for data rates and throughput. The PCIe bus is a point-to-point bus which connects a single upstream and single downstream component which provides higher bandwidths than a multi-drop topology bus structure.
As the number of desired channels in a test system increase, design and test become more complicated requiring better channel-to-channel correlation and additional equipment to address multiple channels. PXI and AXIe modular instruments are ideally suited for high channel count applications due to their easily integrated instrument architectures, small form factor, scalability, and module-to-module synchronization. Module-to-module synchronization, in particular, provides advanced measurement capabilities for more challenging multi-channel applications. The compact and scalable configuration of PXI allows engineers to build the test system they need today and add modules for more channels or instruments as their test system requirements change in the future.
For more than 75 years, Keysight has been unlocking measurement insights. Along the way, we’ve created industry-leading test equipment in different shapes and sizes a full-size benchtop, small benchtop, handheld and modular. In every form factor, our goal is to deliver the performance needed to stay on the leading edge in industry. For modular instruments, our hardware innovations are focused in two specific forms: PXI and AXIe. We’re putting our unrivaled performance—and consistent measurement science—into the RF, microwave and high-speed digital instruments in our PXI and AXIe portfolio.
To provide time-saving starting points for test system creation, we’re documenting Reference Solutions that address specific application areas that range from power amplifier testing to satellite signal monitoring. Keysight Reference Solutions provide the right combination of hardware, software, and measurement expertise through programming examples – highly optimized for specific applications. Reference Solutions show you how to get the most out of your test equipment, helping you achieve half the time to insight. Keysight Reference Solutions increase confidence in solving test challenges, enable quick evaluation of the test solution’s performance & capability for a specific application, dramatically reduce the time it takes to integrate a new test system into a test environment and leverage Keysight’s measurement expertise and software for specific application requirements.
Some of our test reference solutions are :
LTE/LTE-A Multi-Channel Reference Solution
5G Waveform Generation and Analysis Reference Solution
Radio Test Reference Solution
