The Automated Test Blog

There is no doubt that we now are facing an economic headwind. Customers I’ve visited around the world are trying to understand how this headwind will affect their business and what they can do to put themselves in the best position to weather this storm, and perhaps even come out of this down cycle stronger than they are now. More and more test engineers are looking at how to optimize their approach to test more with less.

Testing more with less means that you may have to reevaluate your approach to test, and indeed, it is in disruptive conditions such as we now face that new ideas are the most prone to take hold. I believe that modular, software defined test systems provide the greatest opportunity for testing more with less – regardless of the dimension where optimization is needed. For example, optimizing the test speed of a production system is often the best path to decreasing test costs. For other applications, reconfiguring a single tester to test multiple devices yields the best results. And in very complex testers, the capital cost may the focus for cost reduction. For each of these situations, and in many others, the software-defined approach has proven time and time again to deliver dramatic improvements.

Let me share a few examples. In a production system, time is, quite literally, money. If you can reduce test time by ½, then you may be able to put half the number of testers at the end of a line. Wireless devices, in particular, are often expensive and time consuming to test. Many cellular phones are still tested with a inefficient method called “call-processing”. In this approach, a device called a “one-box tester” is used to actually simulate a phone call to the device under test. Bringing a phone up into a call is slow and is unnecessary to test if the device is correctly assembled. This would be like testing a television by watching a movie on it, instead of simply sending it a test pattern and verifying the result. More and more cellular handset manufacturers are moving to a software-defined test system that instead tests the physical layer signal of the device and uses signal processing in software to perform the necessary tests to verify each type of wireless standard. This technique is often 2-5 times faster than call-processing, which results in huge savings for the manufacturer.

Another example of achieving cost savings with a modular, software-defined approach is to use the flexibility of software to reconfigure a system to test many different types of devices. Another challenge in wireless test is that many devices have multiple wireless standards. My beloved iPhone, for example, now has 5 radios! Often, these different standards have required different instruments with their own vendor-defined measurement routines. A software-defined system can be reconfigured to test each standard with the same hardware. And when standards inevitably change and evolve, a software-defined system is in a much better position to be able to react to these changes.

A final example is in semiconductor ATE. Many semiconductor devices are tested on so-called “Big iron” testers. These testers have the sophisticated digital infrastructure and pin-electronics to test high performance semiconductors such as processors and SOCs. For simpler devices with low target prices, such as a MEMs sensor or an RFID, however, these testers may be overkill. Because they have the infrastructure to support high performance, it is difficult to scale them to these simpler requirements. A modular, open system such as PXI, though, has a very low entry cost and can be configured with only the minimum required capability, which results in lower capital expenditure.

So, in these turbulent economic times, it will be up to test engineers to innovate using the latest technology to meet the challenges of testing more with less. And those companies and individuals that do this the best will be able to come out of this difficult time stronger than before and ready to take advantage of new opportunities as conditions improve.

I just finished reading the book Bill and Dave: How Hewlett and Packard Built the World’s Greatest Company. Its a good read that focuses on the personal story of how two engineers built the most successful high technology company of their generation. Its also a good reminder of how much Hewlett and Packard laid the groundwork for the current generation of technology companies. Among other things, they pioneered “Flex-time”, the “Open Door” policy, “Management by Walking Around”, profit sharing, employee stock purchase plans, casual Fridays, “10% time” MBOs, company barbecues, and the cubicle (but don’t hold that last one against them!). All of us in the technology field owe a lot to those two pioneers.

Last week, I was in China for a conference. The economy continues to boom there; its amazing to see how much has changed since my last trip just two years ago. The skyline in Shanghai has grown immeasurably, the piracy and knock off brands have been pushed ‘underground’ (though, its still pretty easy to get a fake Rolex), and the evidence of China’s growing middle class is apparent - its almost as easy to get a real Rolex now at the many upscale shops around town. But one of the most pronounced changes is the growing pollution in Shanghai and Beijing. I only flew through Beijing, but I couldn’t even see the terminal from our plane as we taxied in. As one of my colleagues noted, you could look right at the sun, which was only a soft glow behind the yellow smog. Shanghai wasn’t quite as bad, but as we drove into the city, we all noticed our sinuses clogging and a distinct itch in the back of our throats. Another colleague attempted to take a jog in the city, but gave up after a few blocks.

So that raises the question that everyone has been asking: How is Beijing going to host the world’s premier athletic competition in a mere few months? The Chinese have instituted a decade long plan to clean up Beijing’s air, but opinions vary on how well it has worked so far (and my experience last week would suggest that it hasn’t). There are also more drastic contingencies planned, such as shutting down factories, restricting automobiles, and even seeding clouds to force rain, in an effort to “cleanse the air”. Some athlete’s aren’t so confident - one of the world’s premier marathon runners today announced that he may pull out of the Olympic due to health concerns related to the pollution.

So what’s the long term solution to the pollution in China and elsewhere around the world? Probably not restricting traffic or seeding clouds. The problem will be ultimately solved through consumer demand and engineering innovation, or green engineering . Consumer demand is what is causing the huge uptick in green products and corporate sustainability plans. Sure, there is a lot of hype out there (now called “Greenwashing“), but the net effect of all the focus on environmental sensitivity is a positive one. Even more sustainable are the discoveries and innovations in the scientific and engineering community. China’s pollution, for example, is primarily the result of coal power plants (a new plant opens in China every week to 10 days) and automobiles. Both of these industries are seeing huge investments in research to fund cleaner, more sustainable alternatives. The global investments in renewable energy reached $100B in 2006 and its projected to grow to more than $750B in the next 10 years. Research abounds in more efficient solar, wind, and even wave energy production. There is also a large investment in researching and productizing alternative fuel and zero emissions vehicles.  We don’t yet know which of these innovations will prove most successful, but innovation, combined with a capitalistic system which rewards it, will ultimately triumph.  Its only a matter of time before these inventions are not just a novelty, but a economically sustainable business delivering zero emissions but also better performance and lower cost of ownership than their fossil fuel predecessors. It might not be in time for the Beijing Olympics, but hopefully it will be in time to clean the air for the next generation of China’s urban population.

Wireless mobile devices will fundamentally change the way we use and interact with the Internet. As I’ve posted before, I am a unabashed iPhone user. And I’ve started to notice some curious things about my use of the Internet now that its with me all the time and easily accessible. For one, my Internet usage has gone up by an order of magnitude. I don’t think I’m exaggerating - I literally mean 10x. And let’s be clear, I was already a heavy Internet user. Now I use it 10 times more. This also means I access the Internet on my phone at least 10 times more than I do on my PC. I’ve grown so accustomed to the device that I find myself surfing the web on it while sitting in front of my laptop. I have also noticed that my expectations for Internet content has changed. For example, my expectation for real time content has gone up dramitically. I check news sites like cnn.com several times each hour and expect news updates. No new headlines in the last 20 minutes? Maybe I should try another site. I also notice that I use the device to augment my own knowledge on the fly by searching acronyms, names, etc., while in conversation or in a meeting. I don’t think I’m at all alone in this trend: Google recently reported that 50 times more traffic from iPhone users than from other mobile devices. Think about that - 50 times! When you make a tool like Google more accessible, dramatic things can happen. I’ve also talked to several colleagues (NI has a density of iPhone users that I doubt is topped anywhere outside of Cupertino), and they report a similar phenomena.

So, the question is, what is driving this change? I think first and foremost, we’re starting to really see the impact of ubiquitous wireless connectivity. The iPhone happened to make the full Internet available in way that is as good or better than the experience on the PC. Once the Internet makes the jump to wireless devices, the dynamic of the Internet will really change. The PC will quickly become irrelevant as an Internet device - the number of mobile devices (>1 billion per year) dwarfs the number of PCs (about 250 million per year). As Bolaji Ojo of EEtimes recently stated in his article Wireless is everywhere, ignore it at your peril, “the search is over for the next killer app…it is wireless”.

As an extension of my own personal iPhone observations, I think the new wireless Internet will have some of the following attributes:

• Usage an order of magnitude greater than the current web;
• Significantly increased demand for real time information;
• A two way communication portal, not just an information source (Web 2.0);
• Optimized primarily for mobile devices, not PCs.

It will get even more interesting as the wireless data bandwidth explodes with standards such as WiMAX and LTE. 2008 should be a fascinating year for wireless, particularly, the wireless Internet.

I recently presented at a group called the Semiconductor Test Consortium, or STC. There were two subjects of the talk – learnings from PXI and other industry standards and emerging trends in SOC (System On a Chip) and SIP (System In a Package) functional testing. The latter has been the subject of some interesting discussion of late in the semiconductor test industry.

The challenge that many chip designers face is that the devices are increasing in complexity at a rate that exceeds the advances in testing technology. The result is that the cost to manufacturer complex semiconductor devices is decreasing faster than the cost to test them. In validation, the issue is not only test cost, but overall test time, which can impact the time to validate new silicon and, ultimately, time to market.

As devices begin to resemble complete systems, a higher level test methodology is called for to both reduce the tester’s complexity, as well as provide a tighter link back to the system level design tools. An engineer at Broadcom recently coined the term “Protocol Aware ATE” to describe this need and at the International Test Conference (ITC) this year, there was a panel discussion on this trend. The idea is to create a test system that can perform functional testing of a device by emulating the device in situ, or in its intended surroundings. This requires the capability to model the other components of the system and to interact with the device in real time.

This is similar in many was to functional testing that is already routinely done at the board and system levels. For some devices, this is just stimulus-response type testing performed at the end of the manufacturing process. When real-time response is needed, this is very similar to a technique called Hardware in the Loop, or HIL, used extensively in automotive and aerospace validation testing. For chip testing, the real time requirements are often more stringent. A technology that has promise to meet many of these requirements is the Field Programmable Gate Array (FGPA), also noted as an ideal architecture in the Broadcom paper. A programmable FPGA placed in the tester close to the device under test, can be used to emulate the system and test the device in situ. The FPGA also holds promise as a target that can run system models directly from system level design tools to bring design and test closer together.

One the biggest signs of success factors of PXI has been the increased adoption by major test and measurement vendors. Even though at times they have been hesitant to wholeheartedly support the PXI standard, Agilent, has several product lines in PXI:

•  A line of PXI-based high performance signal generators (N6030A)
• PXI digitizer modules, from their acquisition of Acqiris
• PXI Optical test instruments, form their acquisition of PXIT

Last week, Agilent released new PXI modules in their optical test product line. Their press release notes that the modules offer their customers “a smaller, faster, more cost-effective solution” - precisely the primary benefits of the PXI platform.

Last week was National Instrument’s annual user conference, NI Week. It has become more of a whirlwind every year, and this year set a new bar: over 2500 customers, plus members of the trade press, investors, university professors, partners, and NI employees. I’m still digesting all the feedback and takeaways, but here was my overriding impression: over the past few years, the sophistication of applications that our users have accomplished with NI tools has grown remarkably. I recall judging our application paper contest just a few years ago in the communication category and all the applications submitted were fairly straightforward GPIB-controlled test applications. Today, NI hardware and software are being used in research labs to prototype the latest communication standards, in RF chip validation testers, and in high volume production test of wireless devices. During the NI Week keynotes, we showed leading edge applications of virtual instrumentation, including a ‘mind controlled wheelchair’, a Boeing 787 audio flyover test system, multichannel video streaming, and a cryogenic medical device - all applications of LabVIEW. It really is amazing what our users our accomplishing with our tools.

I am hearing increasingly from customers and other vendors in test and measurement about the need for “Open Analysis”. The need is driven by the increasingly diverse set of applications and thus measurement requirements driven by, among other things, macro trends outlined in the book The Long Tail. As communication standards continue to proliferate, and the pace of change increases, users need tools that can adapt just as rapidly to their changing measurement needs. Instrumentation vendors such as Tektronix, for example, are increasingly offering options for users to plug in third party analysis tools, or export their data to analysis environments for custom processing. Tek’s OpenChoice is “a collection of software libraries, utilities, samples, industry-standard protocols and interfaces”. An example of OpenChoice software is SignalExpress Tektronix Edition, which is used to automate Tektronix instruments and bring data into and open, PC-based environment for further analysis. Tektronix AEs, third parties, or customers themselves can add in their own custom analysis to meet their specific application needs.

I’d like to clarify the difference between these two terms as I have found that there is very often confusion between them. The distinction is entirely in the software model and the programmability of software-based analysis by the instrument user. A Virtual Instrument’s primary programming model is to present raw data to the user for customized measurements. A Traditional Instrument’s primary programming model is to present vendor-defined measurements to the user.

What about Standalone Instruments versus Modular Instruments? This is a question of form-factor, not software, and is therefore entirely orthogonal to whether the instrument is virtual or traditional. A standalone instrument can indeed be used as a virtual instrument. An example is a standalone oscilloscope that is automated to create custom measurements in software. Similarly, it is possible for a modular instrument to present only a traditional use model to the user; VXI instruments, for example, were most often vendor-defined instrument repackaged in a modular form factor.

While the definition of virtual instruments and modular instruments is orthogonal, it is true that many modular instrument standards lend themselves to building virtual instrumentation systems. In order to effectively perform user-defined analysis on a signal, the user must have access to the raw data from the instrument’s acquisition. For high-speed measurements, this requires transferring many megabytes of data from the instrument to a processor to be analyzed in software. High-speed interface buses such as PCI Express, which can transfer data at up to 4 Gigabytes/s, are well-suited to this application. Instrumentation standards such as PXI combine high-speed buses and upgradeable PC-based processors, making it an ideal platform for virtual instrumentation systems.

PXI is celebrating its 10 year anniversary in 2007. Richard Quinnell at Test and Measurement World recently wrote about PXI’s anniversary, highlighting the compatibility it has achieved during this time. For me, its been remarkable to see the growth and changes in this marketplace over the past 10 years, especially all the times that PXI vendors achieved “the impossible”. Here are a few of my favorites:

• 1999 - 50 members and over 200 products. The first few years of the standard saw a rapid adoption by vendors and the release of a lot of products. Grow exceeded expectations in every dimension.
• 2002-PXI’s entry ito RF. Prior to the release of products by National Instruments and Aeroflex, certain vendors had been outspoken that “you could never do RF in PXI”. Last year, Phase Matrix announced that they are taking PXI all the way up to 26.5 GHz!
• 2003 - PXI systems shipments exceed VXI. By 2006, PXI vendors shipped over 10,000 systems per year - 3 times larger than VXI at its peak. Naysayers claimed modular systems would never be mainstream.
• 2004- A 512 Cross-Point Switch. With the release of the PXI-2532, National Instuments put to rest those that claimed the Achilles heal of PXI was switch density.
• 2005-PXI Express. The PXI Systems Alliance did a remarkable job incorporating new technology to achieve a 45-fold increase in bandwidth while preserving backward compatibility. Those that claimed PCI Express would break compatibility become suddenly quiet.
• 2007 - Agilent joins the PXISA. Agilent Technolgies joined other big name vendors such as Advantest, Aeroflex, Keithley, National Instruments, Rohde & Schwarz, and Teradyne. So much for not having any big name companies in PXI!