T. Sudo

Bio: T. Sudo is an academic researcher from Toshiba. The author has contributed to research in topics: Electromagnetic interference & Power integrity. The author has an hindex of 1, co-authored 1 publications receiving 153 citations.

Electromagnetic interference (EMI) of system-on-package (SOP)

Abstract: Electromagnetic interference (EMI) issues are expected to be crucial for next-generation system-on-package (SOP) integrated high-performance digital LSIs and for radio frequency (RF) and analog circuits. Ordinarily in SOPs, high-performance digital LSIs are sources of EMI, while RF and analog circuits are affected by EMI (victims). This paper describes the following aspects of EMI in SOPs: 1) die/package-level EMI; 2) substrate-level EMI; 3) electromagnetic modeling and simulation; and 4) near electromagnetic field measurement. First, LSI designs are discussed with regard to radiated emission. The signal-return path loop and switching current in the power/ground line are inherent sources of EMI. The EMI of substrate, which work as coupling paths or unwanted antennas, is described. Maintaining the return current path is an important aspect of substrate design for suppressing EMI and for maintaining signal integrity (SI). In addition, isolating and suppressing the resonance of the DC power bus in a substrate is another important design aspect for EMI and for power integrity (PI). Various electromagnetic simulation methodologies are introduced as indispensable design tools for achieving high-performance SOPs without EMI problems. Measurement techniques for near electric and magnetic fields are explained, as they are necessary to confirm the appropriateness of designs and to investigate the causes of EMI problems. This paper is expected to be useful in the design and development of SOPs that take EMI into consideration.

Overview of Power Integrity Solutions on Package and PCB: Decoupling and EBG Isolation

Abstract: Mitigating power distribution network (PDN) noise is one of the main efforts for power integrity (PI) design in high-speed or mixed-signal circuits. Possible solutions, which are based on decoupling or isolation concept, for suppressing PDN noise on package or printed circuit board (PCB) levels are reviewed in this paper. Keeping the PDN impedance very low in a wide frequency range, except at dc, by employing a shunt capacitors, which can be in-chip, package, or PCB levels, is the first priority way for PI design. The decoupling techniques including the planes structure, surface-mounted technology decoupling capacitors, and embedded capacitors will be discussed. The isolation approach that keeps part of the PDN at high impedance is another way to reduce the PDN noise propagation. Besides the typical isolation approaches such as the etched slots and filter, the new isolation concept using electromagnetic bandgap structures will also be discussed.

Overview of Signal Integrity and EMC Design Technologies on PCB: Fundamentals and Latest Progress

Abstract: This paper reviews the fundamentals and latest progress of modeling, analysis, and design technologies for signal integrity and electromagnetic compatibility on PCB and package in the past decades. Most results in this field are based on the very rich and highly educational literature produced by Prof. C. Paul in his long scientific career. The inclusion of parameters variability effects is also considered, and it is demonstrated how statistical simulations can become affordable by means of recently-introduced stochastic methods. Finally, the necessity of practical training of designers is mentioned, and an experience relying on realistic PCB demonstrators is illustrated.

PDN Impedance Modeling and Analysis of 3D TSV IC by Using Proposed P/G TSV Array Model Based on Separated P/G TSV and Chip-PDN Models

Abstract: The impedance of a power-distribution network (PDN) in three-dimensionally stacked chips with multiple through-silicon-via (TSV) connections (a 3D TSV IC) was modeled and analyzed using a power/ground (P/G) TSV array model based on separated P/G TSV and chip-PDN models at frequencies up to 20 GHz. The proposed modeling and analysis methods for the P/G TSV and chip-PDN are fundamental for estimating the PDN impedances of 3D TSV ICs because they are composed of several chip-PDNs and several thousands of P/G TSV connections. Using the proposed P/G TSV array model, we obtained very efficient analyses and estimations of 3D TSV IC PDNs, including the effects of TSV inductance and multiple-TSV inductance, depending on P/G TSV arrangement and the number of stacked chip-PDNs of a 3D TSV IC PDN. Inductances related to TSVs, combined with chip-PDN inductance and capacitance, created high upper peaks of PDN impedance, near 1 GHz. Additionally, the P/G TSV array produced various TSV array inductance effects on stacked chip-PDN impedance, according to their arrangement, and induced high PDN impedance, over 10 GHz.

EMI Reduction via Spread Spectrum in DC/DC Converters: State of the Art, Optimization, and Tradeoffs

Abstract: Spread spectrum is a technique introduced for mitigating electromagnetic interference (EMI) problems in many class of circuits. In this paper, with particular emphasis on switching DC/DC converters, we consider the most common and most efficient known spreading techniques, looking for spreading parameters that ensure the highest EMI reduction and the lowest performance reduction in the circuit where the spreading is applied. The result is an interesting tradeoff not only between EMI reduction and performance drop, but also on the EMI reduction itself when considering different EMI victim models. The proposed analysis is supported by measurements on two switching DC/DC converters: 1) based on pulse-width modulation and 2) based on the resonant converter class.

Poly(vinylidene fluoride)-based flexible and lightweight materials for attenuating microwave radiations.

Abstract: Two unique materials were developed, like graphene oxide (GO) sheets covalently grafted on to barium titanate (BT) nanoparticles and cobalt nanowires (Co-NWs), to attenuate the electromagnetic (EM) radiations in poly(vinylidene fluoride) (PVDF)-based composites. The rationale behind using either a ferroelectric or a ferromagnetic material in combination with intrinsically conducting nanoparticles (multiwall carbon nanotubes, CNTs), is to induce both electrical and magnetic dipoles in the system. Two key properties, namely, enhanced dielectric constant and magnetic permeability, were determined. PVDF/BT–GO composites exhibited higher dielectric constant compared to PVDF/BT and PVDF/GO composites. Co-NWs, which were synthesized by electrodeposition, exhibited saturation magnetization (Ms) of 40 emu/g and coercivity (Hc) of 300 G. Three phase hybrid composites were prepared by mixing CNTs with either BT–GO or Co-NWs in PVDF by solution blending. These nanoparticles showed high electrical conductivity and sig...