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This paper introduces a non-destructive and simple setup method for characterizing dielectric liquids over a broad frequency range (up to 30 GHz) using the Djordjevic-Sarkar model. By employing a differential microstrip line and comparing scattering parameters in air-filled and liquid-immersed scenarios, the proposed method achieves precise dielectric constant (DK) and dissipation factor (Df) extraction. 2 Liquid samples (PAO4 and DC-15) were tested using this method. Validation against the cavity resonance method demonstrates a strong agreement for the extracted DK values, with a relative error of less than 1.5 %, indicating high accuracy. However, the method is less sensitive to Df, particularly for low-loss dielectrics, with a relative error of 67 % at the cavity resonance frequency. Despite this limitation, the technique provides a practical approach for wideband dielectric characterization, particularly for applications in immersion cooling and high-frequency electronic systems. 

The increasing demand for higher data rates in modern electronic systems has heightened the challenges of maintaining signal integrity, particularly in addressing farend crosstalk (FEXT). This paper presents a novel approach using absorber-based terminations to perform signal integrity measurements in high-speed PCB designs. The performance of magnetically and electrically loaded absorber materials is evaluated against traditional 50Ω terminations with performance parameters such as S-parameters, Time-Domain reflectometry (TDR), and induced far-end crosstalk voltage. Simulations and experimental measurements demonstrate that electrically loaded absorbers can achieve performance characteristics comparable to high-quality terminations, particularly for reflections and impedance matching. The results indicate that absorbers offer a cost-effective and adaptable solution for termination applications, with the potential for fast application on existing PCB layouts. However, challenges remain in ensuring consistent pressure for optimal performance. The findings in this paper underlines the feasibility of absorbers for terminations. 

This paper presents a comprehensive analysis of the impact of intra-pair PN skew compensation in printed circuit board (PCB) strip line (SL) traces, for a high-speed 224 Gbps lane for the first time. The study investigates the effects of skew compensation placement both with and without via discontinuities. Detailed evaluations are performed in both time and frequency domains, examining critical parameters such as time-domain reflectometry (TDR), input impedance, return loss, insertion loss, and common-mode S -parameters. The findings reveal that, in a simple strip line trace without via discontinuities, the location of skew compensation has negligible influence on signal margins. However, when via discontinuities are introduced, the impact becomes significant on signal margins and common-mode conversion. This highlights the crucial role of skew compensation placement in high-speed designs, where increasingly tight performance margins and reduced PCB dimensions exacerbate signal integrity challenges. The results underscore the importance of careful design considerations to optimize performance in modern high-speed interconnects. 

Abstract Covalent 2D magnets such as Cr₂Te₃, which feature self‐intercalated magnetic cations located between monolayers of transition‐metal dichalcogenide material, offer a unique platform for controlling magnetic order and spin texture, enabling new potential applications for spintronic devices. Here, it is demonstrated that the unconventional anomalous Hall effect (AHE) in Cr₂Te₃, characterized by additional humps and dips near the coercive field in AHE hysteresis, originates from an intrinsic mechanism dictated by the self‐intercalation. This mechanism is distinctly different from previously proposed mechanisms such as topological Hall effect, or two‐channel AHE arising from spatial inhomogeneities. Crucially, multiple Weyl‐like nodes emerge in the electronic band structure due to strong spin‐orbit coupling, whose positions relative to the Fermi level is sensitively modulated by the canting angles of the self‐intercalated Cr cations. These nodes contribute strongly to the Berry curvature and AHE conductivity. This component competes with the contribution from bands that are less affected by the self‐intercalation, resulting in a sign change in AHE with temperature and the emergence of additional humps and dips. The findings provide compelling evidence for the intrinsic origin of the unconventional AHE in Cr₂Te₃ and further establish self‐intercalation as a control knob for engineering AHE in complex magnets. 

The dielectric substrate of printed circuit boards (PCBs) generally consists of epoxy or polyurethane resin and fiberglass, which can be modeled as inhomogeneous dielectric layers (IDLs). IDLs are not homogeneous in the perpendicular direction of the layers’ interface, which means that they constitute an anisotropic material. Thus, the effective dielectric constant (Dk) for IDLs is direction dependent, i.e., mode dependent. In this study, the effective Dk values of IDLs are extracted for different modes using three commonly used full-wave simulation models: the transverse electric (TE), transverse magnetic (TM), and equivalent parallel-plate capacitor models. The results for the TE and TM modes showed a 10% discrepancy. The effective Dk of IDLs was efficiently estimated by the parallel-plate capacitor model based on the layers’ dielectric properties and thicknesses. Moreover, the analytical formulas of resonance frequency for a cylindrical cavity resonator filled with IDLs were derived to extract the effective Dk of the IDLs at different resonance modes, which could be used as a guideline of resonator methods for PCB material characterization. These results correlated with the results from the equivalent parallel capacitor model. Finally, the impact of IDL anisotropy on transmission line loss and time-domain reflectometry impedance was analyzed based on full-wave simulation. 

This paper presents a simplified physics-based model for deep-snapback transient voltage suppressor (TVS) devices with open base BJT configuration. The proposed model is able to capture quasistatic IV curve as well as the transient behavior of the TVS including the initial voltage peak and the device turn on delay. A comparison of simulation and measurement results show that the proposed model can predict the quasi-static and transient behavior of an ESD protection device.