Optimizing Test Time Part 2, The Muscles

In our previous post, we illustrated how shaving a few milliseconds off your overall test time can have a large, cumulative impact for a high volume testing. This impact can be translated into better productivity and lower costs. We looked at how we could cut down the test time without sacrificing the quality of the test by making the 'brain' of the operation - the test software - more efficient. Part 2 looks at the “muscle” – the test instrument. Future posts in the series will cover Synchronization and Connectivity bus.

Part 2: The Test Instrument

Test instruments are the 'muscle' of the test system - where all the physical measurements are made -- and typically account for a large portion of the test time budget. Therefore, it is important that these instruments optimize test time as well as give quality measurement results.

With test instruments, the stronger the 'muscle', the better the performance. Power is related to the computational and processing power of the instrument, such as the CPU speed and RAM. The faster the CPU and the larger the RAM, the better. However, it is also possible for a well-designed architecture and platform to have better performance than a superior processing power. Therefore, look for a combination of a sufficiently powerful instrument and well-designed architecture and platform to find the best test instrument within your budget.

You can also consider doubling the ‘muscle’. Select instruments have capabilities to make parallel measurements so that more than one DUT (device-under-test) can be tested at once. For example, the R&S ZVT Multiport Network Analyzer with its true multiport architecture with one reflectometer per port and independent multigenerator concept can perform simultaneous measurements on all ports of a DUT and possibly more than one DUT. This kind of parallel capabilities can multiply test time savings by many folds.

Having ‘muscle’ power is great, but what if you already have existing instrument? How do you make it work faster? The answer lies in optimization of settings. Look through the settings of the instrument and match it against your test requirements. If your test only requires certain frequency ranges, consider features such as segmented sweep, whereby only frequency ranges of interest are being swept through, while those that are not are skipped. Even simple settings like turning off the front-panel display can shave test times. Take the Agilent 53230A counter for example: by turning off the front-panel display, it can make 75,000 measurements in 1.22 seconds as opposed to 1.35 seconds when the display is on. Be sure to look into ways in which you can optimize the instrument settings without compromising the reliability of the measurements.

To start, look into the datasheet or manual for information on measurement speed or throughput. There may be some recommendations to leverage.

Although the 'muscles' do the work, when it comes to timing, the 'heart' is crucial in ensuring the right work is done at the right time. The 'heart' – synchronization – is up next. Subscribe to our blog to get the entire series delivered.