Essential Principles of Cross Talk and Mitigation Strategies

Fuzz button connectors are extensively used in vertical interconnection for high‐density integrated circuits. This work studied the impact of fuzz buttons under different compression states on high‐frequency signal transmission using theoretical analysis and experimental testing. The resistance values for fuzz buttons with different heights in compression states were measured. The physical dimensions were obtained for sample fuzz buttons subjected to various compression states. The effects of long‐term compression of fuzz button on the resistance values and S parameters of the device under test (DUT) were analyzed. In addition, the high‐frequency parameters were measured for the DUT with fuzz buttons in various compression states. Both a three‐dimensional (3D) electromagnetic field model and an equivalent circuit model for the fuzz buttons under compression states were developed and the results of these two models show good agreement with experimental results. In the circuit model, a fuzz button connector with a three‐wire transmission line structure was modeled as a π impedance network, composed of equivalent inductances and capacitances. It was found that the proposed 3D electromagnetic field model and an equivalent circuit model can accurately predict the effect of fuzz buttons under different compression states on the signal transmission in the affected frequency band. However, the models cannot evaluate the communication performance of the whole system.

Section: Model Developmentmentioning

confidence: 99%

Section: Three‐dimensional Electromagnetic Field Model Developmentmentioning

confidence: 99%

Investigation of signal integrity of fuzz button connectors under different compression states

Wang

Gao

Flowers

et al. 2023

“…The fundamental frequency of the signal can be calculated using the below equation

{f}_{0}=\frac{1}{T},

where T is the period of the excitation signal. The signal bandwidth (BW) can be obtained by the below equation 25

\mathrm{BW}=\frac{0.35}{RT},

where RT is the rise time of the excitation signal. The corresponding shortest wavelength of the excitation signal can then be described by the below equation:

{\lambda }_{\min }=\frac{c}{{f}_{\max }},

where c is the propagation velocity of the electromagnetic wave in free space.…”

Section: D Electromagnetic Field Model Developmentmentioning

confidence: 99%

Impact of impedance compensation structure in coaxial‐microstrip transition section on near‐field radiation

Zhang

Gao

Wang

et al. 2023

Coaxial‐microstrip transition sections are extensively used in radio frequency (RF) circuits, providing electrical interconnection and signal transmission. However, an antipad used for impedance compensation in the coaxial‐microstrip transition section leads to signal return path discontinuity and radiation emission. Accordingly, in this current work, the impact of impedance compensation structure on the near‐field radiation in the coaxial‐microstrip transition section was investigated by theoretical analysis and experimental testing. A 3D electromagnetic field model of a circuit board with an anti‐pad was developed to calculate the S‐parameters and radiation electric field. Based on the characteristics of the electric near‐field probe, a transfer function model was also developed to convert the radiation electric field obtained by the electromagnetic field model into the output voltage for better comparison with the test results. In addition, the effect of the rise time of the input signal on near‐electric field radiation was also studied in this work. The experimental results are in good agreement with the simulation results obtained from the transfer function model. The results of this study provide a better understanding of the electromagnetic radiation characteristics caused by the impedance compensation structure and theoretical support for compensation optimization strategy in engineering.

“…Differential signal pair has the characteristics of strong antinoise, low crosstalk, and low EMI. [4][5][6] Many CM filter designs of different structures have been published to solve the CM noise problem. This letter researched the defected ground structure (DGS) structure filter to achieve a larger CM noise suppression bandwidth.…”

Section: Introductionmentioning

confidence: 99%

“…Differential signal pairs are often used to design computers to increase transmission rates, which reduces EMI issues with signal interference. Differential signal pair has the characteristics of strong antinoise, low crosstalk, and low EMI 4–6 . Many CM filter designs of different structures have been published to solve the CM noise problem.…”

Section: Introductionmentioning

confidence: 99%

Wideband common‐mode suppression filter using defected corrugated reference plane structures

Lin

2023

This article describes a broadband common‐mode filter for suppressing common‐mode (CM) noise in high‐speed differential signals. The filter used a novel defected corrugated reference plane (DCRP) structure. It used structure changes to impact the characteristic impedances in the CM current return path, which caused many approach transmission zeros. The main purpose generated a larger CM noise stopband effect. The experimental results showed that the frequency domain can reduce the CM noise over 9.29 dB from 3.67 to 17.03 GHz. The fractional bandwidth was 129%. The CM noise can be improved by 68.2%. The insertion loss in differential mode (DM) was kept at less than −1.611 dB from DC to 20 GHz with good signal integrity. The eye diagram can support a 16 Gb/s transmission rate in the time domain. The DCRP structure filter supports high‐speed computer buses up to PCI Express 4.0, SATA Express, HDMI 1.4, and USB 3.2, which meet current computer products' needs.