ProgReport27.doc - Rensselaer Polytechnic Institute

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					                    100 Gb/s per Channel
             Scrambler/Descrambler Circuits for
           Optical Serializer De-serializer (SERDES)
            Links using IBM's 8HP, 8XP and 9HP
                SiGe HBT BiCMOS Processes

               NRO contract number NRO000-09-C-0160
                “High Bandwidth Oscilloscope & Probe”

                             August 1, 2011

                     Twenty Seventh Monthly Report

                               J. F. McDonald
               Electrical Systems and Computer Engineering
                      Center for Integrated Electronics
                      Rensselaer Polytechnic Institute
                              Troy, NY 12181
                       Graduate Student: Ryan Clarke

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Gantt Chart

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Table of Contents
   1. Introduction                              4
   2. Progress                                  4
          A. 100 GHz Oscilloscope               4
          B. Oscilloscope Testing Integration   7
          C. 50 GHz Bandwidth 10-pin Probe      8
          D. Cadence & Kit Upgrade              10
   3. Future Work                               10

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1. Introduction
A new 100 GHz oscilloscope has arrived and setup. The instrument is a LeCroy Wave Expert
100H capable of sampling up to 100 GHz signals using a SE-100 sampling head. A 10-pin micro
probe rated for bandwidths up to 50 GHz has also arrived. Currently, progress has been made in
upgrading our IBM kits and cadence design software. Future work will be discussed on where to
expand on the design which has been created.

2. Progress
A. 100 GHz Oscilloscope
Figure 1 and 2 is a snapshot of the brand new LeCroy Wave Expert 100H time sampling
oscilloscope and tabulated specifications, respectively. The oscilloscope is capable of sampling
signals up to 100 GHz using the sampling module SE-100.

                     Figure 1 – LeCroy Wave Expert 100H Oscilloscope

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             Figure 2 – LeCroy Wave Expert 100H Oscilloscope Specifications

A SE-100 sampling head which is rated for sampling signals up to 100 GHz and a sampling
extender which will allow the sampling head get as close as possible to the probes are included
in the package. The following tabulates the specifications on the sampling module.

                  Figure 3 – Sampling Modules Electrical Characteristics

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This will be extremely beneficial signal the loss due the cable will be at a minimum. Testing this
on the new scope, there was a difference of about 90 mV-pp between a 3” and a 12” cable.
Current testing of the scope has been limited to a maximum frequency of 14 GHz due to the
maximum 14 GHz prescaler trigger input frequency which can be seen in figure 2

The scope has many features which include an advanced jitter analysis which LeCroy claims to
be 3 times more accurate that the average oscilloscope currently on the market.

The following figure shows a 14 GHz sine wave sampled from the oscilloscope (top) and a
zoomed in image of the selection of the signal (bottom). Figure 5 shows an eye diagram of the 14
GHz signal.

             Figure 4 – Sampled 14 GHz Sine Wave with a Zoomed-In Selection

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                  Figure 5 – Eye Diagram of the Sampled 14 GHz Signal.

B. Oscilloscope Testing Integration

The trigger of the scope has a maximum input frequency of 14 GHz. The scope is capable of
sampling to bandwidths up to 100 GHz with the SE-100 which is the sampling we currently do
acquire. The underlying limitation now is on the 1mm cable and the microprobe itself. 100 GHz
is beyond the requirement of testing the scrambler chip. At the very least, 40 GHz testing
bandwidth is required for 80 Gb/s. Testing with higher bandwidth equipment will improve the
quality and accuracy of the measurements. The sampling head has a 1mm connector and a 1mm
to 2.4mm connector has been provided in the package which will allow for a 50 GHz cable to be
connected to a 50 GHz microprobe. All required equipment has now been obtained and ready to
be used on the scrambler chip which is expected to arrive between the months of September and
October of this year.

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C. 50GHz Bandwidth 10-pin Probe
The following three figures show pictures of the high bandwidth 10-pin probe. Figure 6 shows
the complete assembly of the multi-wedge probe set including the 2.4mm connectors. Figure 7
shows a close up view of the probe arms which gives strength and rigidity to the signal probe
tips. Figure 8 shows an even closer view of the signal probes tips itself.

                      Figure 6 – Complete 10-pin Multi-Wedge Probe

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           Figure 7 – 10-pin Multi-Wedge Probe Zoomed In on the Probe Arms

           Figure 8 – 10-pin Multi-Wedge Probe Zoomed In on the Probe Tips

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D. Cadence & Kit Upgrade

Upgrading the kit and the cadence software has run into a few problems. Cadence 6 is the new
version of cadence and it is practically a full overhaul to software structure. This has led a few
complications in getting this configured with the IBM kits. All data is backed up and still can be
used on cadence 5 until cadence 6 bugs are all worked out. The most recent IBM kit, however,
does not run on cadence 5. This should not be a critical issue since little changes have been

3. Future Work
Currently, the cadence and kit upgrade is in the works. Upcoming month a cascaded design of
the scrambler cell will be developed. The layout is planned to be laid out in such a way to make a
chip design square. An implementation with 8XP kit will be used to offer a prediction of the
performance of 9HP. Simple implementation will done to check to take the current cell which is
optimized for 8HP will be applied then some modification will be applied to the current trees to
optimize for 8XP.

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