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S-parameter characterization of high-speed interconnect components is prone to numerical, modeling, and/or measurement error due, in part, to the sampled nature of the data. This is a problem in modern package design where extensive signal integrity simulations are required to validate a system’s performance. This article presents a new method of treating sampled S-parameter data where a criterion is developed to clearly state the minimum number of S-parameter frequency points required to adequately represent an analog physical system in the frequency domain. This criterion is akin to the Nyquist principle when sampling in the time domain. Based on this principle, the proper time-domain representation of S-parameters can be obtained using the inverse fast Fourier transform (IFFT). However, in order to use the IFFT, the bilinear transformation is applied to the vector fit S-parameters to place them in the z-domain. From the z-domain, the proper discrete impulse response is obtained. A lower bound, based on the discrete Heisenberg principle, is also offered to deal with frequency–time resolution of the S-parameters. The proposed method is successfully tested in the measured and simulated S-parameter data. The usefulness of this method is to accurately represent the time-domain behavior of the physical system S-parameter data, i.e., time delay causality, and, therefore, facilitates the applications of well-developed digital signal processing (DSP) techniques in S-parameter sampled data.

A method for extracting the effective copper surface roughness of a laminate in situ is introduced. The rough copper attenuation as a function of surface roughness is removed from the total attenuation. The residual loss is fit to coefficients, and an error is calculated based on the remaining apparent surface roughness contribution. When the error is minimized or when the apparent surface roughness contribution is nearest zero, the effective surface roughness is found, and the dielectric attenuation is isolated by subtracting the rough copper attenuation from the total attenuation. Using this value, accurate broadband permittivity values can be extracted by simply measuring the S-parameters of two stripline transmission lines. Further, the extracted dielectric electrical properties are calculated with a higher accuracy than the existing methods that neglect copper surface roughness. A supplementing method to unwrap the phase constant is also included in this work to avoid errors do to the length of the devices. Previous methods of extracting laminate material properties that consider copper surface roughness rely on cutting the sample to make a cross-section and observe the surface roughness directly. In this work, the effective surface roughness is gathered without destroying the sample.

The Non-Metallic Connector (NMC) was introduced several years ago. In this new iteration, the NMC has been redesigned to accomplish data transfer with an optical interface and wireless power transfer with the use of micro-inductors. To demonstrate the wireless power transfer (WPT), an NMC for a USB flash drive is proposed. The challenge for the WPT design is to understand the geometric and physical constraints inside the connector housings (form factor). Equations for optimal power transfer performance in this miniature environment are presented followed by simulations that verify the efficient WPT. Initial measurements on the proposed WPT system also validate the concept.

A method of extracting the effective copper surface roughness of a laminate in situ is introduced. The rough copper attenuation, as a function of surface roughness, is removed from the total attenuation. The residual loss is fit to coefficients, and an error is calculated based on the remaining surface roughness contribution. When the error is minimized or when the apparent surface roughness contribution is zero, the effective surface roughness and dielectric loss contribution are found. Using this extracted dielectric loss, broadband causal laminate electrical properties are calculated with higher accuracy than existing methods that neglect copper surface roughness. The new method uses S-parameter measurements of stripline traces and does not require a cross-section of the sample.

In this paper an extension to the previous work done in the Jitter modeling for high speed communication links, is presented. For the technique called “Bin Multiplication” the work was done only for NRZ systems, we derived a new general equation to find the total number of combinations for any-level system: PAM4, PAM8, etc. Moreover, the bin multiplication algorithm is developed for correlated random jitter, modeled using correlated Gaussian probability density functions (pdfs). With this approach, a more generalized and accurate jitter modeling, for PAM 4 is provided.

Plastic materials form an important constituent of interconnect devices. Wideband characterization of the dielectric properties of interconnect plastics is indispensable to characterize the signal integrity performance of interconnects, which are used in a large number of consumer electronic devices. In this paper, wideband dielectric characterization of Triethylene Glycol Dimethacrylate Ester (TrEGDMA) organic plastic material is presented using transmission line technique for the frequency range of 1–17 GHz. Debye models are used to analytically describe the frequency dependency of TrEGDMA dielectric properties obtained from the measured data. These models can be utilized by commercial software packages to assign frequency dependent material properties to a solid made of TrEGDMA plastic.

Differentially-routed traces on printed circuit boards typically incorporate loose in-pair coupling when compared to the coupling between the traces and the ground planes. Loose coupling facilitates in-pair skew correction without affecting the differential-mode impedance. However, practical channels combine printed circuit boards with other components that have different degrees of in-pair coupling which could affect the crosstalk among adjacent pairs. This paper examines the effects of different degrees of in-pair coupling on near end crosstalk in the absence of in-pair skew. The analysis will help printed circuit board designers to choose the desired degree of in-pair coupling to achieve targeted near end crosstalk performance.

A hash map implementation of the link analysis technique for obtaining jitter is proposed, under non-linear receiver conditions. The jitter PDF obtained from the link analysis, which typically assumes an LTI system, is passed through the I/O non-linear CMOS receiver voltage characteristics, obtaining the final jitter distribution. Simulations show promising results.