Ahmad Hosseinbeig

Characterization of Relative Complex Permittivity and Permeability for Magneto-Dielectric Sheets

A new method is developed to extract relative complex permittivity and permeability of magneto-dielectric sheets. Two test fixtures are used to separately extract electric and magnetic properties of the material under test (MUT). The unknown parameters corresponding to dispersion models of the complex permittivity and permeability of the magneto-dielectric sheet are optimized by comparing the measured <inline-formula><tex-math notation=LaTeX>

Human body impedance modelling for ESD simulations

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A study on correlation between near-field EMI scan and ESD susceptibility of ICs

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A novel z-directed embedded component for the reduction of voltage ripple on the power distribution network for PCBs

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Transient electromagnetic co-simulation of electrostatic air discharge

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On secondary ESD event monitoring and full-wave modeling methodology

Motivated by understanding the ESD-induced currents from body-worn, wire and hose connected medical equipment is exposed to, a computer simulation is presented to estimate the impedance of a human body relative to ground. This 3D model is the basis for transient field calculation. A Method of Moments (MoM) frequency domain solution is transformed into time domain via IFFT for further circuit level time domain simulations. The human body is modeled as a homogeneous dielectric with frequency-dependent complex permittivity. Dependence of the impedance on the position of discharge and posture of the human body is investigated. The simulation resultsare compared with measurements and demonstrate capturing of general tendencies of measured curves.

A novel Z-directed embedded component for the reduction of voltage ripple on the power distribution network for PCBs

Correlation between near-field EMI scan and ESD susceptibility scan of a cellphone CPU IC is investigated. It is shown that the ESD susceptibility of the CPU IC depends on the activity of the IC. Based on the obtained correlation between these two scans, it is sufficient to perform the ESD susceptibility scan only by running the application which highly loads the CPU. This reduces the ESD susceptibility measurement time as well as the probability of physical damage to the IC.

Systematic analysis of ESD-induced soft-failures as a function of operating conditions

A new capacitor package and PCB embedding technique is introduced to significantly reduce the system power distribution network impedance at the pads of surface mounted integrated circuits. The capacitor is multi-layer ceramic capacitor (MLCC) that is a right cylindrical shape with via channels in the outer wall along the axis of the part. The capacitor called a Z-Directed component (ZDC) is then pressed into a hole in the PCB. The connections to the component are then made by the copper plating process similar to via hole construction. This new configuration dramatically improves the PDN performance of PCBs with fewer components than the conventional solution with SMD decoupling capacitors.

Methodology for Analyzing ESD-Induced Soft Failure using Full-Wave Simulation and Measurement

Transient electromagnetic co-simulation is used to simulate the currents in a discharging rod. The simulation model simultaneously solves Maxwells equation and the arc resistance equations in time domain to estimate the currents and fields for a given geometry, charge voltage and arc length. The Rompe-Weizel model is used to obtain the time dependent arc resistance, and results from different simulation methods are compared to measured data.

Z-Directed Component (ZDC) Technology for Power Integrity Applications

An adjustable spark gap structure is designed to generate Secondary ESD. The primary and the secondary discharge current are directly measured. The setup is modelled using CST full-wave simulation software. The goal is to predict secondary ESD induced current levels using simulation methods, to assist designers in product development in the early design stage.