OUTLOOK 2017: Rising to the testing challenges

4 mins read

A straw poll of design engineers is quite likely to conclude that testing the products they design is becoming increasingly challenging.
There’s a number of reasons for this; apart from component functionality becoming more complex and devices coming in smaller packages, the need for a range of connectivity is adding another dimension to the testing challenge. And that’s before time to market considerations are factored in.

Jithu Abraham, oscilloscope product manager for Rohde & Schwarz, noted: “Faster processors, efficient power management modules, digital communication interfaces, local program memory, data memory and sensors all operate in the smallest spaces and pose great challenges to the community. And, with applications such as IoT gaining more prominence, the next integration step is radio modules.”
Dean Miles, senior EMEA technical marketing manager with Tektronix, added: “Today’s design engineers must often debug complex devices, with integrated analogue and digital signals, serial buses and wireless communication.

“This means designers are having to wear new hats while troubleshooting and debugging designs.”

Art Mcfall, marketing brand manager, EMEAI, with Keysight Technologies, added: “Most recently we see devices with many more application-specific serial protocols and integration with RF communication. But regardless of the protocol or medium, finding the cause problem quickly remains the goal for the R&D engineer.”

Miles sees the biggest change as having come from wireless connectivity. “Many of the latest communications standards featuring frequency hopping. In addition, devices such as frequency synthesisers also use frequency hopping techniques, so there is the need to examine spectral content in real time.”

Neil Crossan, technical marketing engineer for core test and RF with National Instruments, pointed to growing complexity. “Gone are the days where a test system was required to test a limited number of functions. Take the mobile phone as an example. Early devices made and received calls and text messages. Music players and cameras were separate devices. A modern smartphone contains all of these separate devices, plus more, making the test system more complex.”

And Abraham agreed: “Integrated RF modules, more efficient batteries and power management systems add complexity to an engineer’s testing needs.”

As technology develops, the challenges are likely to increase. What are these challenges likely to include? Geoff Kempster, product manager with rental specialist Microlease, suggested that, if anything, the pace was likely to increase. “We’re now talking about 400Gbit/s – even terabit –communications rates. In addition, designs will incorporate more and more on the same platform. An IoT module, for example, might feature cellular, WLAN, Ethernet and Bluetooth communications, as well as USB and other ports, while supporting more than one form of data storage.”

Picking out just one thing, Miles said: “A massive change that will increase complexity is just over the horizon as the industry shifts from the traditional USB connector to the Type-C 24pin reversible-plug connector.”

With a raft of challenges on the horizon, what is the test and measurement sector doing to help engineers?

“Demanding measurement tasks require the integration of different test and measurement devices,” said Abraham. “For example, the RTO2000 is an all in one test instrument for multi domain applications. Apart from voltage level checks and jitter analysis, it can decode protocol based serial interfaces for control signals and perform frequency domain analysis.”

“Apart from component functionality becoming more complex and devices coming in smaller packages, the need for a range of connectivity is adding another dimension to the testing challenge. And that’s before time to market considerations are factored in.”

Graham Pitcher

Mcfall pointed to two things.“Firstly, the user interface and off-line control/analysis software is much more intuitive, yet more powerful. This means engineers don’t have to learn a complex menu or even know the user interface. Now, if you can see it, you can use it.

“Secondly, we have been increasing the capability of an oscilloscope beyond it being ‘just a scope’. With the addition of features such as protocol analysis, cross pattern triggering and RF power and spectrum analysis, today’s scope is a ‘Swiss Army Knife’ device.”

Crossan, from National Instruments, pointed out the company offers a platform that scales from design to test. “With products such as LabVIEW and TestStand, engineers are able to develop test programs and integrate them seamlessly into a test management software environment with limited effort.”

Where do the experts see test and measurement instrument design heading in the next few years?

Microlease’s Kempster highlighted the fact that manufacturers are offering more and more features in software. “I am also seeing increasing flexibility being offered by the major test instrument manufacturers in the licensing terms that they are offering on software upgrades.

“A natural evolution is the subscription model adopted by Microsoft – buy a basic hardware platform and pay a subscription fee to keep it updated with new functionality and capabilities as they are released.”

Miles noted to be ahead of demand and in a position to incorporate new technologies when customers need them. “A key focus has emerged around integrating more capability into an oscilloscope and doing it in such a way that it simplifies the engineer’s life. With complexity on the rise, modern mixed signal designs are proving to be a worthy adversary to designers. Embedded systems design engineers are having to wear multiple hats in order to efficiently troubleshoot and debug the latest designs. This means tackling such activities as designing power supplies and measuring power efficiency, or tracking down sources of noise.”

Crossan believes the future for test will be very different. “Over the next few years, I suspect that many test systems will make the move to software defined, modular instrumentation, allowing the user full control of what exact tests will be performed.”

Looking into the future, what might a mid range oscilloscope have to offer design engineers?

Kempster said: “Ten years ago, 1 to 2GHz would have been a top of the range scope; today, that’s a mid-range instrument. Looking ahead five years, I’d say a mid range scope could probably offer a bandwidth of 20GHz – ten times better than today, but still nowhere near the 100GHz performance of today’s top instruments. However, the trend we are currently seeing for functions to be implemented in software and accessed through a license key will develop.”

Miles said the mainstream scope market – covering bandwidths from 500MHz to 3.5GHz – continues to be exciting. “But budgets are often constrained in this segment, so users will continue to ask for high value integrated scopes. We don’t anticipate major changes in overall functionality; instead, the focus will be on evolutionary refinements and steady gains in price/performance.”

Keysight’s Mcfall noted: “Though it is an impossible task, both technically and financially, to put every feature we could in one product, we could see improvements in RF front end design and better probing for lower level signal inputs and higher resolution digitisers, even greater multi-instrument functionality and better networking and remote control features.

“There will be greater integration of the data from instruments and software which enables a one pass, closed loop design cycle; from concept and simulation in all domains – such as digital, analogue, RF and even thermal – to the final design and verification.”

Crossan brought a different perspective. “Mid range scopes in five years will offer the ability to have a user interface on a phone or a tablet, allowing for complete control of the device via software and the scope to be tailored to the user’s exact needs.”

The good news for embedded designers is that companies developing test and measurement equipment face the same challenges. “The goal is to deliver as much performance and functionality as possible in a compact package,” Miles concluded, “while making sure the final product fits within the customer’s budget. The products must be reliable, deliver consistently accurate measurements and be field upgradable.”