While nanotechnology helps shrink products—resulting in smaller cars or smaller chips—the expectations from the instruments used to test these small products, have got bigger. A few years ago, analogue oscilloscopes were the only desktop product, till the entry of digital oscilloscopes into the market, which offered more choices to engineers and designers, as per their requirements. There are different categories of oscilloscopes that cater to the needs of multiple segments—handheld scopes, PC based scopes, low range benchtop scopes and high performance scopes.
By Richa Chakravarty
Sunday, August 28, 2011: Increasing areas of application
An oscilloscope (also called scope) has many applications across different verticals. Today, new segments are emerging where the use of scopes is increasing, day by day. Gone are the days when one scope suited all applications. Customisation is the name of the game today, with several customers demanding oscilloscopes that are tailor made for their specific applications. The market is today crowded with customer driven products that are easy to use and meet the constantly evolving needs of a particular vertical.
Electronics design and test teams in nearly every industry, including the computer, communications, semiconductor, aerospace/defence, automotive and wireless industries, continue to produce increasingly sophisticated hardware. Engineers and technicians use oscilloscopes as their primary tools to test and debug those designs. In addition, educators need affordable, industry grade oscilloscopes to help prepare the next generation of engineers. Thanks to the rapid evolution of technology, these scopes are today finding applications in every segment like medical, measuring and metering, electric power industry, manufacturing, monitoring and transmitting signals in broadcasting, IT, robotics, etc. Rapid technology changes in end user markets are making it difficult for oscilloscope vendors to keep up with the changing demands. Moreover, with increasing competition, companies are coming up with newer products, added features and innovations.
Oscilloscopes are evolving technically to meet the requirements of new application areas. The instrument has evolved from being a system dedicated to viewing waveforms, to an operating system based device with various software features and one that is technologically more efficient.
The most significant change is the transition from analogue to digital scopes. Deeper memories, higher sampling rates, colour TFT and LCD wide screen displays, apart from built-in options like a function generator, digital storage oscilloscope (DSO) demonstrator and a multi-channel logic analyser are the major technological developments seen in oscilloscopes today.
We can broadly categorise scopes into real time and sampling scopes. Real time scopes are generally modular or PC based handheld scopes, basic benchtop scopes and high end benchtop scopes.
Handheld scopes: In the handheld sphere, scopemeters are the latest devices available in the market. These battery operated portable instruments are also becoming feature rich. The new scopemeter 190 series II (a handheld oscilloscope) introduced by Fluke, offers four isolated floating channels that help in performing floating measurements on multiple signals while simultaneously viewing and measuring waveform amplitude, shape and timing differences between signals or four test points. “It includes two USB ports that help to easily transfer data to a PC or archive and to share waveforms,” informs Manjunath CS, business unit head, TTL Technologies Pvt Ltd. With four channels, users can inspect input signals, output signals, feedback loops or safety interlocks, simultaneously, to solve problems like signal amplitude, shape variations, induced noise, disturbances across critical circuit nodes, signal timing measurements and synchronisation issues.
UNI-Trend Group offers a diversified product portfolio by providing customers with more innovative, high value added technology products. The handheld digital storage oscilloscope UTD 1102C by UNI-Trend hosts features like six digit frequency counter, USB port, and a bandwidth of 100 MHz and 500 MS/s real time sampling rate. It also has multimeter and special LCD features.“Right from educational institute to aviation industry, from military application to industrial plants, UNI-Trend oscilloscopes have a very wide area of application. These battery operated portable instruments come in sealed, dust proof and drip proof cases to withstand harsh working environments,” informs Deep Arora, proprietor, Noble Electronics, a distributor of UNI-Trend.
Mixed signal scopes: A significant innovation in oscilloscopes is the emergence of mixed signal oscilloscopes (MSO) with both digital and analogue signals for debugging. An MSO is a combination of an oscilloscope and logic analyser. The advanced versions available in the market today come with pinpoint triggering. “With the needs of design engineers becoming more complex and with companies getting conscious about quality checks, the demand for DSOs and MSOs is increasing,” informs Manish Kwatra, managing director, Metro Electronic Products.
The market offers oscilloscopes with analogue channels (two or four) as well as digital channels (up to 16) in a single instrument. Inbuilt function generators and hard disks, advance triggering options, faster update and sampling rates, more storage and memory, touchscreens, low noise, serial data analysis tools, the Windows platform and increased bandwidth (ranging from 50 MHz to 32 GHz) are some of the new features that have helped in faster operations in a wide variety of applications.
“Today, customers can get 10 different application software packages in a single scope, which allows them to cover a range of different tasks. Our new MSO/DPO 5000 series mixed signal oscilloscope platform provides engineers the analysis functionality and performance they need for a number of applications, all in one instrument,” informs Naresh Narasimhan, country marketing manager, Tektronix India Pvt Ltd.
Digital scopes: The latest digital measuring instruments are the most complex systems that demand precision, scalability and speed, and manufacturers are equally involved in developing innovative features. Interesting innovations are helping oscilloscope functions to keep up with the pace of developing technologies and customer requirements. Also, vendors see a growing need, particularly for mid-range products that can provide performance measurements at an affordable cost. However, the major challenge for manufacturers in this case is to meet all customer requirements by keeping abreast with the latest technological advancements. Bandwidth enhancement techniques like digital signal processing (DSP) boosting and frequency interleaving, accompanied with the latest software are being loaded in the scopes.
“Although India is moving at a fast pace in terms of technical advancements, we still lag in the hardware design and circuitry sphere. We are strong on the services part and in software development, but scopes are a mix of both, hardware as well as software. We have to ourselves improvise on the design and circuitry to be able to match the evolving requirements,” adds Sadaf Arif Siddiqui, senior technical marketing engineer, Agilent Technologies India Pvt Ltd.
Today, oscilloscopes are equipped with features like powerful trigger modes, which include edge, video, pulse width and slope. To make search and navigation easy, scopes are currently installed with advanced search and mark capabilities. This allows up to eight searches simultaneously. Besides, every instance of a found event is marked, and a table listing information is found for each event. This, coupled with a multi-tier pan/zoom control set, not only makes search simple for users but also speeds up the process.
The digital oscilloscope DS1000CA series from Scientech Technologies Pvt Ltd comprises 2GSa/s real time scopes with a 50GSa/s equivalent sample rate, and a bandwidth of up to 300 MHz. These high performance scopes not only capture real time instantaneous signals, but also record details of repeated signals. Scopes from the DS1000A series have a refresh rate of up to a 2000 wfms/s, which enables users to capture instantaneous signals and abnormal signals quicker.
Rohde & Schwarz’s RTO digital oscilloscopes combine excellent signal fidelity, a high acquisition rate and a real time digital trigger system with a compact device format in the 1 and 2 GHz class with a sampling rate of 10 Gsamples/s per channel. “By encompassing digital technology, the new RTO scopes bring a new dimension to the market. The instruments’ highly integrated ASIC and the use of multiple parallel processing paths drastically reduces blind time facilitating a speed of 1 million displayed waveform per second,” informs Nasser Salim Jariwala, head business development (naval accounts, education) and regional manager, west India (T&M), Rohde & Schwarz.
A technological innovation from Agilent—the MegaVision IV—results in a very fast update rate. The product’s innovative chipset, designed in Agilent’s proprietary high speed high voltage InP HBT, results in a 32 GHz true analogue bandwidth scope, which provides superb signal integrity for characterising and debugging the fastest interfaces. While one can make a scope with more discrete functional blocks, however, performance is limited due to a variety of systems integration issues (thermal, I/O speeds, bus widths, power dissipation, cost, CPU/FPGA MIPS).
Says Sadaf Arif Siddiqui, “By integrating, we can take advantage of high performance internal buses reaching market leading waveform update rates and signal visibility into users’ systems. This also lowers system power, space and cost.”
Adding to the gamut of feature-rich scopes is LeCroy Corporation’s WaveMaster 845Zi-A, world’s highest bandwidth real time oscilloscope at 45 GHz, claims the company. “Our new product WaveRunner 6Zi offers pathbreaking features, including a tilting display that helps engineers choose the best screen orientation for viewing. WaveRunner 6Zi is a scope available in 12-bit resolution,” says Prabhanjana Rao, regional sales manager, India, ASEAN, ANZ, LeCroy Corporation.
Intelligent software: Various application specific compliance testing software (for standards) are also being loaded on oscilloscopes to cater to the needs of different market segments. In-built support for connectivity to a computer or the network is the key specification that is driving the next generation of scopes. These come with the universal serial bus (USB) host feature, so the waveform image can be captured directly onto a USB flash drive without the need for a PC.
Users demand connectivity not only for waveform data transfer but also for control and remote access of the equipment. Thus, Ethernet, USB and general purpose interface bus (GPIB) have become key specifications in next generation oscilloscopes. Today, users demand performance along with ease of operation. As USB is the most commonly adopted standard in the PC world, you do not have to write the code or install drivers separately while connecting hardware using the USB port to your computer.
Digitisation is yet another feature that has made it easier to take the oscilloscope signal onto a PC. With the advent of digitisation, the same signal is captured in the memory and can be seen on the DSO screen or taken to a PC via USB, RS-232, GPIB, LAN, etc. Connectivity through various standards and modes has thus become the biggest trend in oscilloscopes today. As computers continue to deliver higher performance and speed, they have become an attractive option for higher deliverables in test and measurement.
While USB has become the standard today, the future may see scopes with Bluetooth connectivity that will help in quick transfer of data to mobile devices. However, one thing that has been driving the market is higher bandwidth scopes with more information on rapidly changing waveforms.
So we can see that interesting innovations are happening to enable oscilloscope functions to keep up with the pace of developing technologies and customer requirements. Vendors see a growing need, particularly for mid-range products that can provide performance measurements at an affordable cost.
Electronics Bazaar, South Asia’s No.1 Electronics B2B magazine