Rapid Fabrication of Soft,Multilayered Electronics for Wearable Biomonitoring

Soft integrated electronics are key components for emerging applications in wearable biomonitoring, soft co‐robotics, and physical human–machine interaction. They are composed of soft and elastically deformable circuits and sensors that are combined with packaged microelectronics for signal processing, power regulation, and communication. While promising, widespread use of soft wearable electronics is currently limited by the lack of robust fabrication techniques to rapidly, efficiently, and precisely assemble soft and rigid components into multilayered systems. Here, an efficient digital fabrication approach is presented to create highly customizable wearable electronics through rapid laser machining and adhesion controlled soft materials assembly. Well aligned, multilayered materials are created from 2D and 3D elements that stretch and bend while seamlessly integrating with rigid components such as microchip integrated circuits, discrete electrical components, and interconnects. These techniques are applied using commercially available materials and components and the fabrication of thin, lightweight, customized sensor skins is demonstrated in under an hour. These fully integrated wireless devices conformably bond to the hand and are successfully used for monitoring hand gesture, pulse rate, and blood oxygenation. These materials and methods enable custom wearable electronics while offering versatility in design and functionality for a variety of applications through material selection and construction.     

Hochfrequenz-Schaltungsdesign auf Basis Multilayer-Hybridtechnologie

The continuous miniaturization-process of wireless communication products requires more and more specific design- and simulation methods. Design engineers have to find the right trade-off between miniaturization and functional performance regarding production influences. For the realization of radio-frequency and microwave circuits the multi-layer hybrid technology has been recently applied and is about to expand to further application fields. Utilizing e.g. low temperature co-fired ceramics (LTCC) up to 30 metallization layers is state of the art. The design of such circuits can be accelerated essentially by applying EM analysis methods. In many cases the EM analysis is the only way to identify, avoid or compensate parasitic couplings between circuit elements at the very beginning of the layout process. The selection of the right analysis method plays an important role. Also the possibility to rapidly adopt designs to new specifications or changing production parameters by utilizing efficient design tools in combination with optimized design work flows is getting more and more important.     

电力电子电路中非线性现象研究的发展综述

对电力电子电路中的非线性研究的发展近况作了较为全面的叙述。指出了从非线性动力学的角度去研究分叉与混沌行为是今后电力电子电路分析方法的一个发展方向。     

多层介质平板结构的传输线等效面模型及相位修正算法

针对电大复杂多层介质结构目标电磁散射特性分析与应用对计算资源和效率的需求,提出了基于传输线理论的等效面模型,推导了相应的相位修正算法,实现对此类目标散射特性的快速准确预估.等效面模型将多层介质平板结构等效为平面,基于传输线理论,采用电路分析中常用的网络分析方法计算该平面的反射系数与透射系数,并通过引入多层介质结构厚度、入射和观测方向等信息实现对反射系数与透射系数的相位修正.仿真结果验证了该文方法的正确性和高效性.      

A Test Platform for Dependability Analysis of SoCs Exposed to EMI and Radiation

With the IEC 62.132 proposal, the roadmap for standardization of Electromagnetic (EM) immunity measurement methods has reached a high degree of success. The same understanding can be taken from the MIL-STD-883?H for Total Ionizing Dose (TID) radiation. However, no effort has been made to measure the behavior of electronics operating under the combined effects of both, EM noise and TID radiation. For the reasons pointed out, the combined-effect measurements should be mandatory when dealing with Systems-on-Chip (SoCs) devoted to critical applications. In this paper, we present a configurable platform devoted to perform combined tests of EM immunity and TID radiation of SoCs according to the international standards.     

Robust power grid network design considering EM aging effects for multi-segment wires

This paper presents a number of power grid network design and optimization techniques that consider the electromigration (EM) effects for multi-segment interconnect wires. First, we consider a new EM immortality constraint due to EM void saturation volume for multi-segment interconnects. It helps reduce conservativeness in the EM-aware on-chip power grid design. Along with the EM nucleation phase immortality constraint, we show that both EM immortality constraints can be naturally integrated into the existing programming based power grid optimization framework. Second, to mitigate the overly conservativeness of the immortality constrained optimization methods, we further explore three strategies: we first size up failed wires to meet one of the immortality conditions subject to the design rules; second, we consider the EM-induced aging effects on power supply networks for a target lifetime, which allows some short-lived wires to fail and optimizes the remaining wires; third, we propose a large change sensitivity-based optimization scheme to perform localized fixing based on recently proposed coupled EM-IR drop analysis method. Numerical results on a number of IBM-format power grid networks demonstrate that the new method can reduce more power grid area compared to the existing EM immortality constrained optimizations. Moreover, the new method is able to optimize power grids with nucleated wires, which would not be possible with the existing methods. Results also show the sensitivity-based localized power girds fixing can fix EM-induced IR drop violations in a few minutes for synthesized power grid networks from ARM core designs.     

Computer-Aided Analysis of RFI Effects in Digital Integrated Circuits

A computer-aided analysis procedure based upon a modified Ebers-Moli transistor model is used to predict RFI effects in bipolar integrated circuits (IC's). The procedure is applied to a digital IC to determine the RF power levels that cause several EM susceptibility thresholds to be exceeded.     

基于概率表达式的MPRM电路功耗计算方法

采用基于信号概率的功耗计算模型进行MPRM（Mixed Polarity Reed-Muller）电路功耗优化,信号概率计算是功耗计算的关键.提出一种基于概率表达式的MPRM电路功耗计算方法.该方法兼顾信号概率计算的时间效率和准确性,对MPRM电路中不存在空间相关性的信号通过在电路中传播信号概率的方式计算其信号概率,存在空间相关性的信号则利用概率表达式计算其信号概率,并在电路中传播概率表达式以解决空间相关性问题,在此基础之上根据基于信号概率建立的解析动态功耗和静态功耗计算模型计算电路功耗.为进一步提高时间效率,该方法采用二元矩图表示概率表达式.使用基准电路对所提出方法进行了验证,并与其他采用不同信号概率计算方法的MPRM电路功耗计算方法进行了比较.结果表明所提出方法准确有效.     

数字环境下“电力电子技术”教学方式的改进

本文针对“电力电子技术”课程中电路类型多和波形分析不易的特点，采用Flash动态演示课件，再现电路的动态特性。我们可以借助Matlab仿真软件，使得复杂的电力电子电路系统分析、参数的设计和器件本身性能的观察变得具体而有效。用仿真软件代替部分物理实验，可有效摆脱课堂学时少的制约。     

Online Energy Management for Hybrid Electric Vehicles

Hybrid electric vehicles (HEVs) are equipped with multiple power sources for improving the efficiency and performance of their power supply system. An energy management (EM) strategy is needed to optimize the internal power flows and satisfy the driver's power demand. To achieve maximum fuel profits from EM, many solution methods have been presented. Optimal solution methods are typically not feasible in an online application due to their computational demand and their need to have a priori knowledge about future vehicle power demand. In this paper, an online EM strategy is presented with the ability to mimic the optimal solution but without using a priori road information. Rather than solving a mathematical optimization problem, the methodology concentrates on a physical explanation about when to produce, consume, and store electric power. This immediately reveals the vehicle characteristics that are important for EM. It is shown that this concept applies to many existing HEVs as well as possible future vehicle configurations. Since the method only focuses on typical vehicle characteristics, the underlying algorithm requires minor computational effort and can be executed in real time. Clear directions for online implementation are given in this paper. A parallel HEV with a 5-kW integrated starter/generator (ISG) is selected to demonstrate the performance of the EM strategy. Simulation results indicate that the proposed EM strategy exhibits similar behavior as an optimal solution obtained from dynamic programming. Profits in fuel economy primarily arise from engine stop/start and energy obtained during regenerative braking. This latter energy is preferably used for pure electric propulsion where the internal combustion engine is switched off.      

Interconnect reliability dependence on fast diffusivity paths

The reliability of interconnects in modern integrated circuits is determined by the magnitude and direction of the effective valence for electromigration (EM). The effective valence depends on local atomistic configurations of fast diffusivity paths such as metal interfaces, dislocations, and the grain boundary; therefore, microstructural variations lead to a statistically predictable behavior for the EM life time. Quantum mechanical investigations of EM have been carried out on an atomistic level in order to obtain numerically efficient methods for calculating the effective valence. The results of ab initio calculations of the effective valence have been used to parametrize the continuum-level EM models. The impact of fast diffusivity paths on the long term EM behavior is demonstrated with these models.     

Complex behavior in switching power converters

Power electronics circuits are rich in nonlinear dynamics. Their operation is characterized by cyclic switching of circuit topologies, which gives rise to a variety of nonlinear behavior. This paper provides an overview of the chaotic dynamics and bifurcation scenarios observed in power converter circuits, emphasizing the salient features of the circuit operation and the modeling strategies. In particular this paper surveys the key publications in this field, reviews the main modeling approaches, and discusses the salient bifurcation behaviors of power converters with particular emphasis on the disruption of standard bifurcation patterns by border collisions     

Electrothermal simulation and design of integrated circuits

An accurate prediction of the electrothermal behavior of power integrated devices is required to design circuits in an efficient way. An electrothermal simulator (ETS) is a combination of SPICE with finite element code, in a relaxation procedure. It simulates the full electrothermal behavior of integrated circuits. Static and dynamic simulations of typical examples, reveal the value of ETS for high-power applications. Some specific design rules are derived. They are simple formulas, which estimate the temperature (gradients) on chip. They can be used before any CPU-time consuming simulation takes place which allows a more efficient design and prototype phase     

Power integrated circuits—A brief overview

A brief overview of developments in power and high-voltage integrated circuits is presented. The technology can be classified into two types: 1) smart power devices that contain one or more common drain, vertical power transistors with control, and protective circuitry built on the same chip, and 2) high-voltage integrated circuits that combine lateral high-voltage with CMOS logic and analog bipolar circuits on the same chip. These technologies are being aimed at display drivers, telecommunications, motor drives, power supplies, and automotive electronics. A rapid growth in their application in the future can be expected.     

Distributed integrated circuits: an alternative approach tohigh-frequency design

Distributed integrated circuits are presented as a methodology to design high-frequency communication building blocks. Distributed circuits operate based on multiple parallel signal paths working in synchronization that can be used to enhance the frequency of operation, combine power, and enhance the robustness of the design. These multiple signal paths usually result in strong couplings inside the circuit that necessitate a treatment spanning architecture, circuits, devices, and electromagnetic levels of abstraction     

Power-Conditioning Circuitry for a Self-Powered System Based on Micro PZT Generators in a 0.13-$muhbox{m}$ Low-Voltage Low-Power Technology

The concept and design of a power-conditioning circuit for an autonomous low-power System-in-Package (SiP) is presented in this paper. The SiP's main power source is based on the use of micropiezoelectric generators. The electrical model of the power source, which has been obtained based on experimental measurements and implemented on Cadence Analog Artist's Spectre simulation environment, is explained. The model has been used to simulate the power source with the power-conditioning electronics over the entire design process. Finally, the simulated and experimental results of the developed integrated power circuits, which are formed by a rectifier and a low-power bandgap reference voltage source to define the threshold voltage for the closed-loop regulation process, are also shown. These circuits have been designed using a commercial 0.13-$muhbox{m}$ technology from ST Microelectronics through the Multi-Projects Circuits (CMP) Techniques of Informatics and Microelectronics for Integrated Systems Architecture (TIMA) service.      

一种新型多层低温共烧陶瓷三级带通滤波器

提出了一种新型多层低温共烧陶瓷(LTCC)三级带通滤波器的结构及其设计方法。首先,利用电磁场仿真软件对各谐振器的谐振特性,谐振器与外部电路的耦合特性,以及谐振器之间的耦合特性进行了分析,绘制出电路设计中需要的各种曲线。在此基础上得到三级切比雪夫响应带通滤波器的尺寸和频响曲线。其次,在第1和第3级谐振器之间引入交叉耦合,并通过改变该交叉耦合的强弱,在阻带中产生位置可调节的传输零点,从而显著地增大传输零点附近的衰减。通过上述场与路相结合的设计方法,获得了尺寸小、频率选择特性好的多层LTCC三级带通滤波器。     

Keeping chaos at bay

The use of electronic circuits in studying chaotic dynamics and control are reviewed. Since all chaotic systems have several properties in common, simple circuits are analogous to much more complicated ones, such as lasers. Consequently, the methods developed to control chaos in electronic circuits are applicable to many diverse physical systems. The controlling device itself is a high-speed analog circuit. In applying perturbations, no calculations are made; instead, trial-and-error adjustments are used to locate the desired behavior. The initial observations of chaos in electronics, the development of the Ott-Grebogi-Yorke method for calculating the perturbations needed to stabilize a periodic orbit in a chaotic system and the occasional proportional feedback method, and their applications are discussed