The hottest new era of automated testing

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The new era of automated testing

in more than 30 years, the scientific and technological community has witnessed Moore's law in various practices

the density of transistors doubles every 18 months, which greatly improves the performance of electronic equipment. This can be seen not only in the recent Intel i7 processor, but also in many constantly "reducing" technologies. For example, 64GB solid-state drives can now reach the size of a stamp. These technological advances have brought about a substantial reduction in costs. For example, LCD screens that used to cost hundreds of dollars can now be integrated into cheap greeting cards. Because with faster, smaller and cheaper equipment, the entire industry has also witnessed the explosion of a generation of emerging products. These products often integrate many tools, such as GPS positioning system, digital camera, etc. In addition, these tools often have the function of software definition. Users can download application software to make their devices more suitable for their personalized needs

with the continuous emergence of technological innovation, it is increasingly a challenge to test every breakthrough technology. For example, adding wireless local area technology to the next generation of products will add 50 new related tests to the original products. Fortunately, Moore's law is equally applicable to the next generation of test platforms and modular test instruments. With the solution of software definition, especially the production of tires as a key part of bicycles - only the development of material solutions with the advantages of wear resistance, abrasion resistance, chemical resistance and durability, the improvement of the performance of these test systems can fully keep up with the development of the equipment to be tested

from rack test system to PXI (PCI expansion for instrument system)

for decades, engineers have designed some automatic test systems by using the same traditional desktop instruments as in engineering experiments and building them layer by layer on the rack. The rack system is connected to the computer through an instrument control interface, and the program on the computer ensures the automatic operation of the system. Although these rack systems can complete certain functions, they are not used as envisaged by the designer of the instrument

the traditional desktop instrument is designed for the experimental platform, which will be used when engineers or technicians want to manually test or detect the failure of an instrument. In the rack system, the screen, knob and button of the instrument often become a waste of space and money. Further, these instruments are not specially designed to measure speed or data throughput like those automatic instruments. On a design experimental platform, the measurement time of ten seconds is negligible, but when this measurement method is used to measure thousands of equipment on a production line, it may mean huge economic losses

compared with traditional rack mounted desktop instruments, using PXI, you can get a solution that is smaller, more cost-effective and more suitable for your needs

– jessy Cavazos, Frost & Sullivan

figure 1 Unlike traditional rack mounted instruments, engineers can continuously improve the performance of the PXI system throughout its life cycle by upgrading the controller

in the past few years, industrial automation testing has reached a turning point and is now rapidly changing to PXI. PXI, which is specially optimized for automated testing, provides a faster, smaller and more cost-effective solution than rack instruments. Harris RF communications, a supplier of military multi band tactical radio equipment, recently received many orders for its Falcon Series High-Performance radio equipment. The company needs a more advanced testing method so that it can test more radio equipment at the same time. Harris chose Ni TestStand software and PXI hardware as the software and hardware development platform of its next generation test system. Using Ni platform, Harris can not only increase the number of tested radio equipment, but also reduce the test cost of each radio equipment by 74%

The recent global test manager survey of Ni confirms this turning trend. In the survey, more than 70% of the test managers indicated that they would use PXI as the core technology of at least one of their next generation automatic test systems to further shorten the start-up time of the enterprise. In sharp contrast, only 30% of test managers choose to continue to use rack type test instruments in their automatic test system

"using the new technology platform based on Ni PXI, we can reduce the cost to 1/3 of the original while ensuring the integrity of measurement and performance, and improve the throughput of semiconductor testing to 10 times the original."

– ray Morgan, on semiconductor

suppliers of traditional desktop instruments have also made great investments in PXI. For example, in September, 2010, Agilent Technologies announced its support for the PXI platform and launched more than 40 PXI modules. Agilent has joined the PXI system alliance with more than 60 suppliers. As an industrial alliance to promote and maintain PXI standards, this alliance ensures that the investment is in an open and multi supplier (fair competition) environment

Figure 2 The new Ni pxie5665 provides industry-leading RF performance, and compared with the same rack solution, the cost is reduced by 40% and the volume is reduced by 90%

Moore's law will bring PXI to the future

PXI has obtained great benefits from Moore's law by using ready-made technologies in the market. Using transistors that are only 1/2000 in size 20 years ago, Ni has created a high-performance RF instrument in a 3upxi module that is only 1/10 the size of the original desktop instrument. The space occupied by the rack instrument is effectively reduced, and the weight and power consumption of the instrument are reduced. Analog devices has been using traditional automated test equipment (ATE) to detect its MEMS microphone. When it turns to PXI test system, the company can reduce the weight of their test system by 66 times and the power consumption, but try to reduce it to 1/16 of the original. The container loading cost of loading an ATE system in the past is equivalent to the development cost of the whole PXI test system now

The effect of

Moore's law is also significantly reflected in the processing capacity of PXI. Using the modular controller architecture, engineers do not need to replace the chassis and the instruments in the chassis, but simply replace the controller, which can increase the additional processing capacity. In order to improve performance, they can easily replace an old system built in 2001 with a controller using the latest Intel Core i7 processing chip with a working frequency of 2.5 g flops, so that the new system can run at the frequency of 35g flops. Advanced processing capabilities are critical for computing intensive applications, such as RF signal processing and analysis. For example, TriQuint semiconductor company replaced the traditional desktop instrument with PXI based automatic test system, and realized the time-consuming reduction of 6% to 14% in the characteristic test of GSM, edge and WCDMA power amplifier. Using Ni PXI modular instruments, the company's testing time for new product features was reduced from two weeks to one day

pxi not only provides a smaller and faster solution, but also continues to promote the improvement of test performance of various platforms. The new Ni pxie-5665 vector signal analyzer (VSA) provides the best RF test performance, including industry-leading phase noise, amplitude accuracy and dynamic range. Compared with the previous desktop instruments, the new VSA still achieves the best performance with a cost reduction of 40% and a volume reduction of 90%. Another example of leading measurement technology is the new Ni pxie-5186 digitizer. The digitizer was jointly developed by Ni company and Tektronix (the world's best oscilloscope manufacturer). It is now the highest performance PXI digitizer on the market except for the automobile transmission shaft fatigue performance test bench. It has a bandwidth of 5GHz and a sampling rate of 12.5gs/s

software development

when PXI provides us with a faster, smaller and more cost-effective choice, its practical significance lies in providing a real software defined solution. Unlike traditional desktop instruments with specific or supplier setting functions, PXI test system is defined by its software. Just as engineers can download applications to personalize their intelligence, they can now personalize their test systems according to their specific devices to be tested

pxi system software is constantly upgrading with the complexity of the tested equipment. When engineers test a wireless local area system on a chip, they no longer need to test and confirm the effectiveness of components through input excitation and waiting for output. In fact, the test system often needs to debug the equipment based on the communication of real-time digital protocols (such as I2C, pciexpress, SPI, etc.), and finally, in turn, synchronize the RF measurement. This complexity requires software to achieve a higher level of abstraction, so as to model, control and test these systems

Figure 3 When testing complex systems such as chips integrated with wireless local area networks, new testing abstract software and new testing capabilities are needed

fortunately, tools such as NI LabVIEW graphical system development software can meet this requirement. The graphical programming environment similar to the desktop instrument interface that has been used for 25 years enables test engineers to model complex excitation response systems, including complex timing and synchronization. In addition, engineers can also directly download the same code to the user accessible FPGA on PXI for embedded signal processing, personalized protocol communication, and so on

"Ni PXI platform can greatly reduce our development time while ensuring great flexibility and real-time performance. Using LabVIEW can ensure the development and use of real-time controllers and FPGA modules in the same environment, help us achieve the effect of rapid integration, and finally get an independent and reliable product."

– Miguel n ú EZ, Instituto de astrof í Sica de Canarias (IAC)

as stated in Moore's law, newly developed devices are faster, smaller and cheaper than ever before. In order to keep up with the development of the equipment to be tested, test engineers must turn to the PXI based test system

– Matthew Friedman

Senior Product Manager of PXI platform of Ni company, director of PXI system alliance and co chairman of marketing department. Search @pxi on Twitter to add follow Matthew, and you can get the latest PXI update message

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