Generate four channels of high-speed data

-October 24, 2017

Testing high-speed digital circuits and systems often requires data patterns. Whether you're characterizing cables, connectors, PCB traces, or other transmission lines, you need to generate known patterns to measure parameters such as loss and jitter. The ASNT_MPSG pattern generator from Adsantec can product bit patterns at rates up to 40 Gbps on each of its four channels.

text Controllable over a USB port, the ASNT_MPSG can produce nine commonly used pseudorandom bit sequence (PRBS) signals from PRBS7 through PRBS31. If you need quaternary PRBS (QPRBS) signals, the ASNT_MPSG can generate two data streams. All bits have rise/fall times of 8 psec. Output amplitude is adjustable up to 1.4 V.

To use the ASNT_MPSG, you must provide a clock with a frequency of half the selected data rate. To generate a 28 Gbps pattern, you need a 14-GHz clock source. You'll likely use and oscilloscope to view eye diagrams, which is why the ASNT_MPSG provides a sync triggering output with clock divide ratios from 4 to 1024.

You can control the ASNT_MPSG through a Windows app that provides a GUI. There, you can select PRBS patterns from a drop-down menu and select signal amplitude using a slider control. Once you're set up test parameters, you can save them in a text file to recall later. In addition, you can inject bit errors, which are injected as a 256-bit vector that's XORed with the PRBS patterns. You can also define pulse width of injected errors.

Price: $89,000 Adsantec, ASNT_MPSG product page.

Martin Rowe covers test and measurement for EDN and EE Times. Contact him at Follow me on TwitterVisit my LinkedIn page

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