Technion – Israel Institute of Technology Department of Electrical Engineering Winter 2009 Instructor Amit Berman Students Evgeny Hahmovich Yaakov Aharon

Agenda Objectives System Overview SW Block Diagram Progress Report Summary Zero Crossing - Detailed Eye diagram - Detailed TIE Jitter Trend – Detailed Jitter Histogram/PDF - Detailed GUI – Detailed Future Work Time Table 2

Objectives Understanding Agilent’s Jitter analysis methodology and background Design and implement software for calculating Jitter parameters based on Agilent’s scope measurements Demonstrate and analysis the results on high-speed printed circuit board Compare the method to other popular jitter measurements 3

System Overview Waveform Generator High-speed printed circuit board Agilent’s scope PC 4 LinkLink to Equipment Parameters

SW Block Diagram Data Input *.csv format Zero Crossing TIE Jitter Trend Histogram Eye Diagram Bathtub Curve Jitter Extrapolation PDF CDF TJ Jitter FFTDJRJ Numerical Output Graphical Output Internal Function

Progress Report Summary Zero crossing calculation – 90% Eye Diagram - done TIE Jitter Trend – 70% (“difficult” jitter debug) Histogram & PDF – 70% (“difficult” jitter debug) GUI – 40% Bathtub Curve – 20% Jitter extrapolation TJ(BER) measurement Jitter FFT DJ extraction RJ - DJ separation 6

Zero Crossing 7 Zero crossing function = 0 each time the wave trend crosses zero voltage level (red points on the graph) Potential inaccuracies may occur due to hysteresis Zoom

Eye Diagram Eye diagram generated using repeated graph plotting with 1 UI periods from one plotting area to another Difficulty Process time is very long Solution The eye diagram plot will be implemented as an optional calculation 8

TIE Jitter Trend - Algorithm 9 TIE (n) is the min difference of the zero crossing (n) timing from adjacent ideal zero crossing time In addition, the mean of the TIE meas. – stands for the skew of the trace, should be subtracted

TIE Jitter Trend - Results Scope Analysis Mathlab Analysis Difficulties Analysis give good results only for the “simple” jitter case Possible solution may be changing the sampling rate / memory depth -9.44E-09Min TIE 9.56E-09Max TIE 1.90E-08Range 10

Jitter Histogram/PDF Scope Calculated PDF Difficulties Resolution received is lower then expected 11

GUI Defined user interface and visible parameters Implemented acquisition of data file and variables 12

Future Work Zero Crossing Filtering the zero crossings caused by hysteresis TIE Jitter Trend Debug for “difficult” jitter Histogram & PDF Improving resolution and correlation to scope GUI Variables callback implementation and algorithm writing Bathtub Curve CDF implementations, x-scale resolution setting Jitter extrapolation TBD TJ(BER) measurement Implementing the algorithm for measuring BER from the bathtub curve plot Jitter FFT Implementation and scaling DJ extraction Implementation using Jitter FFT filtering RJ - DJ separation Separation using DJ reverse FFT subtraction from the TIE trend 13

14 Questions

Backup 15

Equipment Overview 16 Waveform Generator High-spee d printed circuit board Tabor Arbitrary Waveform Generator WW2571A Maximum frequency 100 MHz (Practical ~50MHz) Ability to create inner modulation High-speed printed circuit board With ability to create noticeable jitter

Equipment Overview 17 Agilent’s scope PC Agilent DSO80204B scope Bandwidth6 GHz Sample rate40 GSa/s Trigger jitter < 1 ps (RMS) EZJIT+Jitter & Timing Analysis Package PC which include the SW of Jitter Analysis Back