Alfred P. Neves

Alfred P. Neves

Alfred P. Neves, Founder and Chief Technologist at Wild River, has 30 years of experience designing and application development of semiconductor products, capitol equipment design focused on jitter and signal integrity analysis, and has successfully been involved with numerous business developments and startup activity for the last 13 years. Al is involved with the Signal Integrity community as a consultant, high-speed system level design manager and engineer. Recent technical accomplishments include development of platforms and methods to improve 3D electromagnetic correspondence to measure-based methods, including advancing time and frequency domain calibration methods.

Al focuses on measure-based model development, package characterization, high-speed board design, low jitter design, analysis, and training. He earned a B.S. in Applied Mathematics at the University of Massachusetts.

ARTICLES

S-parameters: Signal Integrity Analysis in the Blink of an Eye

Emerging 100 Gigabit Ethernet and 400 Gigabit Ethernet requirements for communication networks have put increasing demands on Internet infrastructure. New methods of design, validation, and troubleshooting to optimize high speed digital channels are being employed in the R&D laboratory. This article discusses new concepts for serial link design and analysis as applied to physical layer test and measurement techniques. Novel test fixtures and signal integrity software tools will be discussed in real world applications in the form of design case studies.


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BER- and COM-Way of Channel-Compliance Evaluation: What are the Sources of Differences?

We analyze the computational procedure specified for Channel Operation Margin (COM) and compare it to traditional statistical eye/BER analysis. There are a number of differences between the two approaches, ranging from how they perform channel characterization, to how they consider Tx and Rx noise and apply termination, to the differences between numerical procedures employed to convert given jitter and crosstalk responses into the vertical distribution characterizing eye diagrams and BER. We show that depending on the channel COM may potentially overestimate the effect of crosstalk and, depending on a number of factors, over- or underestimate the effect of transmit jitter, especially when the channel operates at the rate limits. We propose a modification to the COM procedure that eliminates these problems without considerable work increase.


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Resonant Test Structures: Primer and Signal Integrity Applications

In this paper, we introduce a special class of resonant structure - the Beatty Standard - along with other classic resonators. We examine closely the resonant Beatty Standard, its impedance profile, loss characteristics, and its application to printed circuit board material property extraction. Suited for 32 Gbpsec simulation requirements, the Beatty Standard not only provides engineers a compact structure to perform material property extraction, but also help with establishing a robust design flow.


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