Showing papers on "Decoupling (electronics) published in 2007"

Power Distribution Networks with On-Chip Decoupling Capacitors

Abstract: This book describes methods for distributing power in high speed, high complexity integrated circuits with power levels exceeding many tens of watts and power supplies below a volt. It provides a broad and cohesive treatment of power distribution systems and related design problems, including both circuit network models and design techniques for on-chip decoupling capacitors, providing insight and intuition into the behavior and design of on-chip power distribution systems. Organized into subareas to provide a more intuitive flow to the reader, this second edition adds more than a hundred pages of new content, including inductance models for interdigitated structures, design strategies for multi-layer power grids, advanced methods for efficient power grid design and analysis, and methodologies for simultaneously placing on-chip multiple power supplies and decoupling capacitors. The emphasis of this additional material is on managing the complexity of on-chip power distribution networks.

Measurement and Adaptive Decoupling of Cross-Saturation Effects and Secondary Saliencies in Sensorless-Controlled IPM Synchronous Machines

Abstract: This paper analyzes the effects of magnetic saturation, including cross-saturation and secondary saliencies, on the saliency-based sensorless control of interior permanent magnet synchronous machines. These effects are mitigated by adaptively decoupling saturation-induced saliencies via a structured neural network. This paper includes the identification of the dominant saturation-induced components of the carrier-signal current interfering with the rotor-position-dependent component being tracked, characterization of these components, and implementation of a nonlinear adaptive saturation-induced-component structured neural network model to perform their decoupling.

Soft-switching flyback inverter with enhanced power decoupling for photovoltaic applications

Abstract: A novel single-phase flyback inverter for photovoltaic applications is proposed to achieve low-frequency ripple current reduction on the DC busbar and to draw sinusoidal current into the AC grid. Based on capacitive idling techniques, the proposed circuit topology is derived from a single-ended primary-inductance converter and two-switch flyback inverter to obtain soft-switching operation for all of the active switches. Compared with a buck-boost inverter and other flyback inverter topologies for AC photovoltaic module systems, no extra active switches are used in the proposed inverter to realise both soft-switching and enhanced power decoupling with only four active switches. Peak-current mode control method is employed in the control schemes to ensure pure sinusoidal current with unity power factor on the AC grid. Laboratory experimental results based on a 500 W prototype are provided to verify the effectiveness of the proposed inverter.

A Single-Phase Grid-Connected Inverter with a Power Decoupling Function

Abstract: This paper presents a single-phase grid connected inverter with a power decoupling circuit. In the single-phase grid connected inverter, it is well known that a power pulsation with twice the grid frequency is contained in the input power. In a conventional inverter, electrolytic capacitors with large capacitance have been used in order to smooth the DC voltage. However, lifetime of those capacitors is shortened by the power pulsation with twice grid frequency. The authors have been studied a active power decoupling method that reduce the pulsating power on the input DC bus line, this enables to transfer the ripple energy appeared on the input DC capacitors into the energy in a small film capacitor on the additional circuit. Hence, extension of the lifetime of the inverter can be expected because the small film capacitor substitutes for the large electrolytic capacitors. Finally, simulation and experimental results are discussed.

EMI Suppression in Voltage Source Converters by Utilizing dc-link Decoupling Capacitors

Abstract: Direct current (dc)-link decoupling capacitors are normally used to control the voltage overshoot of switching devices in voltage source converters. This paper analyzes decoupling capacitors' impacts on device electromagnetic interference (EMI) noise as well as on device voltage stress. The design and selection of decoupling capacitors considering both voltage stress and EMI suppression are presented. A new high-frequency EMI filter by utilizing the decoupling capacitors is proposed. The filter is adopted as a local EMI filter for power modules. The integratable characteristics of the proposed filter are discussed. Simulation and experimental results verify the design. This high-frequency filter shows good attenuation for high-frequency EMI noise and voltage overshoot suppression.

Support and decoupling structure for an acoustic resonator, acoustic resonator and corresponding integrated circuit

Abstract: An acoustic resonator assembly includes a layer of high-acoustic-impedance material and a layer of low-acoustic-impedance material made of a low-electrical-permittivity material. This assembly may support the resonator over an interconnect layer or act as a decoupling assembly between two active elements of the resonator. The assembly may alternatively include three low-acoustic impedance layers. Alternatively, the assembly may include three acoustic impedance layers wherein two of the layers are low acoustic impedance layers and the third layer has a higher acoustic impedance than the first two or alternatively is a high-acoustic impedance layer.

Three dimensional multilayer barrier and method of making

Abstract: A three dimensional multilayer barrier (150). The barrier (150) includes a first barrier continuous layer (155) adjacent to a substrate; a first discontinuous decoupling layer (160) adjacent to the first continuous barrier layer (155), the first discontinuous decoupling layer (160) having at least two sections (165); and a second continuous barrier layer (155) adjacent to the first discontinuous decoupling layer (160), the second barrier forming a wall (170) separating the sections of the first discontinuous decoupling layer (160). A method of making the three dimensional multilayer barrier (150) is also described.

Holding device for at least one pipe

Abstract: A holding device for at least one pipe, or the like, is disclosed, the holding device including a housing having a basic body and a lid movable relative to the basic body, and an insert for insertion into the housing. The insert includes at least one substantially U-shaped pipe receiving area into which the pipe is insertable through an insertion slot in a radial direction, so that the insert surrounds the pipe at least in sections. To improve the holding device such that it achieves improved acoustic decoupling together with a considerably simplified structure, it is provided that the insert includes a flexible device configured to close the insertion slot in the closed state of the lid at least in sections.

A Virtual-Flux Decoupling Hysteresis Current Controller for Mains Connected Inverter Systems

Abstract: This paper proposes a new simple method of three- phase, sensorless mains voltage, power control with near constant switching frequency based on a decoupling hysteresis current controller (DHC), and the virtual-flux concept. The virtual flux method is used to extract the mains voltage from the switching state, dc voltage, and line currents. From the desired real and reactive powers the three-phase currents are generated using a DHC. The DHC avoids the switching interaction between the phases, and when a variable hysteresis band is employed a near constant switching frequency is achieved. The method is also extended for high power inverter applications that include an inductance- capacitance-inductance output filter, where some undesirable characteristic, such as filter resonance, have to be compensated. Theoretical analysis is presented and the performance of the proposed method is experimentally verified.

Improvement on an inverted decoupling technique for a class of stable linear multivariable processes.

Abstract: This paper improves an inverted decoupling technique for a class of stable linear multivariable processes with multiple time delays and nonminimum-phase zeros. Two decoupling schemes are proposed based on the inverted decoupling technique. One is a developed inverted decoupling scheme. In this scheme, the decoupler is designed such that the inverted decoupling technique accommodates a wider field than the one introduced in the published literature. However, due to the stability issue, some multivariable processes still cannot be decoupled by the inverted decoupling structure. To solve this problem, another modified decoupling scheme with unity feedback structure is suggested for implementation. The Internal Model Control (IMC) theory is applied here to design PI/PID controllers for the decoupled processes. Furthermore, in the presence of multiplicative input uncertainty, low bounds of the control parameters are derived quantitatively for guaranteeing robust stability of the system. Simulations are illustrated for demonstrating the validity of the proposed control schemes.

Efficient In-Package Decoupling Capacitor Optimization for I/O Power Integrity

Abstract: With high integration density of today's electronic system and reduced noise margins, maintaining high power integrity becomes more challenging for high performance design. Inserting decoupling capacitors is one important and effective solution to improve the power integrity. The existing decoupling capacitor optimization approaches meet constraints on input impedance. In this paper, we show that impedance metric leads to large overdesign and then develop a noise-driven optimization algorithm for decoupling capacitors in packages for power integrity. We use the simulated annealing algorithm to minimize the total cost of decoupling capacitors under the constraints of a worst case noise bound. The key enabler for efficient optimization is an incremental worst case noise computation based on fast Fourier transform over incremental impedance matrix evaluation. Compared to the existing impedance-based approaches, our algorithm reduces the decoupling capacitor cost by 3times and is also more than 10times faster even with explicit noise computation

Neural-Network-Based Nonlinear Adaptive Dynamical Decoupling Control

Abstract: In this letter, a nonlinear adaptive dynamical decoupling control algorithm using neural networks (NNs), a novel technique, is proposed for a class of uncertain nonlinear multivariable discrete-time dynamical systems. By combining open-loop decoupling compensation and generalized minimum variance adaptive scheme with NNs, complete dynamical decoupling is realized. The algorithm is applicable to the systems which are open-loop unstable and nonminimum phase in a neighborhood of the origin Xi. In the domain Xi, it can assure the bounded-input-bounded-output (BIBO) stability of the closed-loop system and can also make the generalized tracking error converge to a neighborhood of zero, whose size is evaluated and depends on the approximation error of the NN. Theory analysis and simulation results are presented to show the effectiveness of the proposed method

Effective Use of Miniature, Multi-Point, Field-Based Current Sensors without Magnetic Cores

Abstract: A methodology for decoupling cross-coupled fields in compact, integrated current sensor arrays is presented. The compactness of the current sensor array elements is made possible by using highly sensitive field detectors based upon giant magnetoresistive (GMR) technology, which offers galvanic isolation, small size (~mm2) and high bandwidth (>1 MHz). By using known geometric relations between the conductor geometries and locations of the field detectors, cross-coupled magnetic field signals can be used to extract necessary current signals, as well as separate unknown disturbance fields. This methodology can also be used to simplify the magnetic biasing requirements of GMR field detectors, including decoupling of the temperature dependence of the biasing magnet. Moreover, the methodology also can be extended to estimate the temperature of the magnet to provide an extra temperature signal for thermal management algorithms.

Dual-axis resonator gyroscope

Abstract: The present invention discloses an improved planar, dual-axis, resonator gyroscope with mechanical coupling of adjacent vibrating members. The primary-mode flexible hinges include a tangential torsion element that largely decouples the out-of-plane resonant frequency from the wafer thickness. The use of separate plates for the force-balance and for the electric spring enables decoupling of the two functions. The invention also provides resonant frequency servo-loop for locking of the sense-mode resonant frequency to the drive-mode frequency, an online self-test, a split force balance loop for self cancellation of the quadrature signal, decoupling of the force-balance and resonant frequency servo-loops and stabilization of the inertial rate-sensing sensitivity—when operated in an open loop mode, all without interfering with the normal operation of the gyroscope. An optional sensing of the Z-axis acceleration perpendicular to the sensor plane is also provided which can be used for compensating acceleration-induced errors.

Interconnecting L/C components for decoupling and its application to low‐field open MRI array

Abstract: Interconnecting L/C components are often applied to decouple the array elements for parallel imaging. Although it has been recognized that interconnecting capacitors and inductors can both be employed for decoupling, quantitative study of this decoupling technique has not yet been presented. In this study, a theoretical analysis for the interconnecting L/C decoupling circuit is provided. The analysis reveals that the required decoupling capacitance decreases with the resonant frequency, whereas the decoupling inductance is independent of the frequency. The inductive decoupling scheme is applied in the design of a four-channel knee coil for 0.5 T open MRI with vertical magnetic field. Experimental results show that good isolations (−19 dB ∼ −45 dB) between coil elements can be achieved and only 5% ∼ 11% degeneration of Q is caused by this decoupling method. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 31B: 116–126, 2007

Modeling and Applications of Ferroelectric-Thick Film Devices With Resistive Electrodes for Linearity Improvement and Tuning-Voltage Reduction

Abstract: Low-cost planar high-Q ferroelectric-thick film varactors (Qap90) are realized and component architectures using resistive electrodes for dc bias are investigated. A basic model for planar capacitors with resistive electrodes in the gap is developed and verified by finite-difference time-domain simulations and measurements of interdigital capacitors with high-resistivity indium-tin-oxide bias electrodes in the gap. An optimized high-Q capacitor design based on a series connection of ferroelectric varactors with resistive bias decoupling is presented. The approach allows the increase of device linearity and the reduction of tuning voltages. Based on this technology, a continuously tunable high-power impedance-matching network for 1.875 GHz with tuning voltages below 60 V was developed, realized, and characterized by small- and large-signal measurements with up to 33-dBm input power. The device requires no external dc-block or RF decoupling and features separated RF and dc contacts. The output IP3 of up to 47.8 dBm verifies the excellent device linearity

Acoustic Decoupling in cMUTs

Abstract: A capacitive micromachined ultrasonic transducer (cMUT) has an acoustic decoupling feature. A cavity is introduced underneath the regular cMUT element, preferably in the substrate, to provide acoustic decoupling. Trenches are also introduced to separate the cMUT elements and to provide further acoustic decoupling. The acoustic decoupling feature may be used in both conventional membrane-based cMUT and the newer embedded-spring cMUT (ESCMUT). Exemplary fabrication methods are also described.

Simple decoupling of a multi-element rf coil, enabling also detuning and matching functionality

Abstract: A coil (36) includes coil elements (381, 382, …, 38n). The coil (36) can transmit radio frequency excitation pulses into an examination region (14) and/or receive responsive radio frequency pulses from the examination region (14). A compensation network (42) includes decoupling segments (98), which each has a selected electrical length at least of a quarter wavelength (λ/4) and is electrically coupled to an associated coil element (381, 382, …, 38n) and a reactive network (100). The compensation network (42) at least compensates coupling between the coil elements (381, 382, …, 38n).

Design, Modeling, and Characterization of Embedded Capacitor Networks for Core Decoupling in the Package

Abstract: Embedded passives are gaining in importance due to the reduction in size of electronic products. Capacitors pose the biggest challenge for integration in packages due to the large capacitance required for decoupling high performance circuits. Surface mount discrete (SMD) capacitors become ineffective charge providers above 100 MHz due to the increased effect of loop inductance. This paper focuses on the importance of embedded capacitors above this frequency. Modeling, measurements, and model to hardware correlation of these capacitors are shown. Design and modeling of embedded capacitor arrays for decoupling processors in the midfrequency band (100 MHz-2 GHz) is also highlighted in this paper.

Device for controlling the frequency of resonance of an oscillating micro-electromechanical system

Abstract: A device for controlling the frequency of resonance of an oscillating micro-electromechanical system includes: a microstructure, having a first body and a second body, which is capacitively coupled to the first body and elastically oscillatable with respect thereto at a calibratable frequency of resonance, a relative displacement between the second body and the first body being detectable from outside; and an amplifier coupled to the microstructure for detecting the relative displacement. DC decoupling elements are arranged between the amplifier and the microstructure.

Decoupling Control for Multiterminal VSC-HVDC Based Wind Farm Interconnection

Abstract: In the paper multiterminal voltage source converter based HVDC (VSC-HVDC) is proposed to interconnect wind farms to AC grids. The method highlights the control at the level of wind generator cluster that comprises several permanent magnet synchronous generators without the primary converters on themselves. For the cluster control, active and reactive power decoupling scheme is applied to adjust the rotational speed of the cluster according to wind speed. The paper studies the schemes to control grid side converter based on the philosophy of linear decoupling control, which aims to control the DC voltage as well as the reactive power of VSC-HVDC. In the proposed control scheme, the two goals are achieved by controlling the q- and rf-axis components of the grid's fundamental current. Simulation has been performed using engineering software Matlab/Simulink to verify the interconnection method and validate the control scheme as well.

Efficient placement of distributed on-chip decoupling capacitors in nanoscale ICs

Abstract: Decoupling capacitors are widely used to reduce power supply noise. On-chip decoupling capacitors have traditionally been allocated into the white space available on the die based on an unsystematic or ad hoc approach. In this way, large decoupling capacitors are often placed at a significant distance from the current load, compromising the signal integrity of the system. This issue of power delivery cannot be alleviated by simply increasing the size of the on-chip decoupling capacitors. To be effective, the on-chip decoupling capacitors should be placed physically close to the current loads. The area occupied by the on-chip decoupling capacitor, however, is directly proportional to the magnitude of the capacitor. The minimum impedance between the on-chip decoupling capacitor and the current load is therefore fundamentally affected by the magnitude of the capacitor. A distributed on-chip decoupling capacitor network is proposed in this paper. A system of distributed on-chip decoupling capacitors is shown to provide an efficient solution for providing the required on-chip decoupling capacitance under existing technology constraints. In a system of distributed on-chip decoupling capacitors, each capacitor is sized based on the parasitic impedance of the power distribution grid. Various tradeoffs in a system of distributed on-chip decoupling capacitors are also discussed. Related simulation results for typical values of on-chip parasitic resistance are also presented. An analytic solution is shown to provide accurate distributed system. The worst case error is 0.003% as compared to SPICE. Techniques presented in this paper are applicable not only for current technologies, but also provide an efficient placement of the on-chip decoupling capacitors in future technology generations.

Superconducting array for high-field magnetic resonance imaging

Abstract: We report on the design of a planar 200MHz superconducting two-resonator array for magnetic resonance imaging (MRI) applications. The array was made out of a double-sided thin YBa2Cu3O7−x film on r-cut sapphire substrate and consists of two 24mm diameter resonators with built-in planar capacitors for coupling to the tuning and matching electronics. Required for the performance of the MRI array, rf isolation of two resonators was accomplished by built-in planar capacitors, and the mechanism of resonator-to-resonator decoupling was analyzed. The signal-to-noise gain as a result of using high-Tc superconductor resonators/arrays was calculated and compared with experimental data.

Automatic placement of decoupling capacitors

Abstract: Disclosed are methods, systems and apparatus for automatically placing decoupling capacitors in an integrated circuit to compensate for voltage drops that might otherwise occur in a power grid. In one embodiment of the invention, the method includes generating one or more regions of the integrated circuit design, with each region having one or more cells, determining an amount of decoupling capacitance required in each region of the integrated circuit design by analyzing each cell in the region, and adding sufficient decoupling capacitor cells to the region to compensate for the potential voltage drop.