A new biquadratic topology for mosfet-C filters using non-balanced structures

A new topology for the realization of MOSFET-C integrated biquadratic filters is proposed which uses an MOS differentiator with non-balanced structures. an interesting characteristic of the new topology is the possibility of realizing lowpass, bandpass and highpass filters with a one-to-one relationship between the biquadratic parameters and the circuit elements. This characteristic allows the implementation of programmable switchable filters.     

A simple dynamic circuit model for mos structure

A new simple circuit model for the MOS (metal-oxide-semiconductor) structure is presented. the model consists of three elements, namely, a linear capacitor, a non-linear capacitor and a C-dynamic element. Each component bears a simple relationship to the physical operating mechanism inside the MOS structure. the model can be used for simulating arbitrary MOS structure circuits under all operating conditions. In particular, it is capable of reproducing the structure's frequency-dependent small-signal characteristics. the model is also shown to exhibit many important and interesting dynamic behaviours under forward, reverse and sinusoidal operating modes. The model is based mainly upon the device's physical operating principles. But perhaps the most significant implication of this model is that it is the first ever to use a dynamic element to model the MOS structure from a physical approach.     

SMOS: A CAD-compatible statistical model for analogue mos integrated circuit simulation

An analogue CAD tool capable of simulating MOS circuit performance variance caused by intra-die variability inherent to IC fabrication processes has been developed. the nucleus of this tool is a general, CAD-compatible, MOS statistical model called SMOS which comprehends the effects of device geometry, circuit layout and transistor bias on parameter variance. an example of the model calculation procedure is presented to illustrate both the modelling algorithms and the process characterization data required by the statistical model. the statistical model is verified through experimental data which show excellent agreement with performance variances predicted by simulation. Implementations of the statistical model in two circuit simulation environments, SPICE and APLAC, are also described. Statistical analysis and simulation of two basic analogue subcircuits, the current mirror and the source-coupled pair, are presented.     

The jaumann structure in wave-digital filters

This paper deals with an extension of the wave-digital filter structures introduced by Fettweis. A new structure is introduced, viz, the digital translation of the Jaumann structure. The Jaumann structure is a well-known canonical realization of analogue, symmetric, grounded lossless two-port networks. With this structure, transfer functions with complex transmission zeros can be obtained in a wave-digital realization, which is not possible by means of a wave-digital ladder filter. Two examples are given, one of which has been implemented using TTL digital integrated circuits showing excellent properties.     

Characteristics of ferroelectric gate mos and mosfets

Abstract

Electrical characteristics of metal-insulator-semiconductor (MIS) capacitors of a variety of ferroelectric materials like lead zirconate titanate (PZT), lead titanate (PT) and barium magnesium fluoride (BMF) on p-silicon have been studied. PZT was deposited by r.f. magnetron sputtering from a composite target and PT from co-evaporation. The films were annealed in oxygen atmosphere in the temperature range 550–700°C for various times. PZT and PT films which are directly deposited on silicon showed low effective dielectric constant.¹⁰ For normal applied bias voltages (±5 V), the C-V curves did not show significant hysteresis. The effective dielectric constant was improved significantly by the incorporation of a buffer layer. BMF film was deposited in ultra high vacuum on a heated substrate and the film was encapsulated by a zirconium oxide layer. The C-V curves for these MIS capacitors shows hysteresis and the direction of hysteresis corresponds to ferroelectric polarization.     

Low-noise and low-sensitivity filters using current-mode coupled biquads

In this paper, it is shown that by adding coupling to biquad pairs to obtain a fourth-order band-pass filter, the output thermal noise is reduced. It is shown analytically that minimum output thermal noise is obtained when the biquads are identical and the negative-feedback factor used for coupling is the same as for the minimum sensitivity to component tolerances and ambient changes. Furthermore, by optimizing the coupled biquads for maximum dynamic range, the output noise is further decreased.     

Dual-amplifier expansion and the design of very-low-frequency (VLF) hybrid integrated active filters

The problem of designing very-low frequency (VLF) active filters in hybrid-integrated form is discussed. It is shown that a class of single-amplifier second-order filters exists with which VLF active filters can be built while at the same time satisfying the constraints imposed by hybrid-integrated circuit technology (i.e. limited resistor and capacitor values). However, with decreasing pole frequency, the gain required of the single amplifier becomes excessive, the gain-sensitivity product (GSP) intolerably high. A solution to the problem is to introduce a second amplifier into the circuit and to distribute the required gain between the two amplifiers. This ‘dual-amplifier expansion’ (DAX) significantly reduces the GSP, enhances the stability of the filter response, and reduces the susceptibility of the filter characteristics to nonideal amplifier effects. On the other hand DAX may not be arbitrarily introduced into a single-amplifier circuit without taking the effect of the limited gain-bandwidth product of the two amplifiers into account. It is shown that the degree by which the gain may be distributed between them is limited by the gain-bandwidth product ratio of the two amplifiers. Much can be improved in this respect by proper frequency compensation of the two amplifiers. It is shown that a combination of the so-called T-compensation and the single-pole single-capacitor compensation produces results that are close to those obtainable with ideal amplifiers with unlimited bandwidth.     

基于多尺度Gabor滤波器的角点检测

为了克服在不同图像上的尺度选择问题,提出了一种基于边缘轮廓线的多尺度Gabor滤波器的角点检测算法。该算法首先利用Canny边缘检测算子提取图像的边缘轮廓;进而用一组构建好的4个尺度8个方向Gabor滤波器的虚部对图像进行平滑,并计算每个像素在其相同尺度下各个方向上Gabor滤波器虚部响应的归一化的和;最后将每个边缘像素点在所有尺度下的乘积作为新的角点测度, 当角点测度大于预设阈值时,则认定该点为角点。将实验结果与经典的Harris、CPDA和He&Yung角点检测算法进行比较,提出的算法在检测准确率、定位误差、噪声稳健性性能指标上,都取得了更好的结果。     

Multiloop feedback unsymmetrical active filters using quads

In this paper, a general design procedure for high order unsymmetrical active filters is presented using a special configuration of quads. Quads are 4th order subsection blocks using biquads in a special manner. It is shown that the determination of network parameters is not dependent on frequency range, and that the design procedure is simpler than other multiloop feedback (MF) topologies. The transmission zeros of the transfer function are derived directly from the zeros of the biquadratic blocks and thus feedforward or summation techniques are not required.     

Design of wave-sc filters using building blocks

Besides switched-capacitor (SC) filters developed for high volume production, e.g. the PCM-codec lowpass filter, numerous low volume applications exist in the area of solid-state filtering. to open up this application field for SC filters, a novel wave-SC filter structure is presented. the filter design using this concept requires only moderate design and layout skills since only a limited library of highly modular building blocks is required. It is also suitable for analogue gate array applications. As will be shown, the wave equations which are known from the theory of wave digital filters can be realized using stray-insensitive SC integrators and SC amplifiers only. Exemplary designs of a lowpass, a highpass, and a bandpass filter will be carried out with the building blocks presented. the theoretical results are verified by measurements at the breadboarded lowpass filter.     

Velocity measurement using phase orthogonal spatial filters

An optical pattern on an object's surface is converted into a component of a specific spatial frequency through a spatial filter, and the movement or the velocity of the object can be estimated from the spatial frequency. An error of the velocity measurement based on the conventional spatial filter method is large in case of low-speed measurement. The authors develop a velocity measurement system based on a new spatial filter method that can compensate the error. This paper presents the system configuration and the compensating method     

Active power filters using resonant pole inverters

The use of a new soft switching inverter topology, the resonant pole inverter (RPI), for harmonic compensator realization, is proposed. Using resonant transitions to minimize switching losses, the topology is suitable for use with GTOs and other gate turn-off devices. Switching frequencies on the order of 10-20 kHz at multikilowatt power levels are feasible. A current-mode modulation strategy is proposed and is seen to realize good spectral characteristics. Extensive simulation and experimental results of a 10 kVA GTO resonant pole inverter switching between 10 and 20 kHz confirm the validity of the approach     

Fully integrated 2.45‐GHz OOK receiver for wireless sensor networks

This paper introduces an optimized receiver architecture using the current‐reuse technique to improve receiver sensitivity while minimizing power consumption. An ISM band wireless receiver with OOK modulation was implemented in the TSMC 0.18‐µm CMOS process. The receiver contains an RF front end, an LC‐tank based LO VCO, an IF amplifier and an OOK demodulator. In addition, the IF amplifier features a self‐mixing elimination mechanism which allows the BER to upgrade more than one order of magnitude. Measurement results show a sensitivity of ?63 dBm given a BER of 10^?3. Using the gain‐improving method, the sensitivity is improved by 4 dB (100‐kbps data rate). Including the bias circuit, overall power consumption is less than 383 μW under a 1.2‐V supply, providing an alternate solution for wireless radio applications. Copyright © 2016 John Wiley & Sons, Ltd.     

基于数学形态学复合滤波和无时延d-q变换的电压暂态扰动识别

暂态电压扰动的识别是当前电能质量领域研究的热点,采用了无时延d-q变换进行暂态电压扰动识别,从而解决了延时60°构造对称三相电压的d-q变换的镜像扰动问题,针对无时延d-q变换易受谐波及高频噪声干扰的缺点,研究了数学形态学结合离散积分的滤波方案,用以取代传统的数字低通滤波器.在LabVIEW中的将该方案与传统数字低通滤波器进行对比,结果表明该滤波方案响应速度快,适应能力强,检测精度高,具有非常优越的综合性能.     

基于数学形态学复合滤波和无时延d-q变换的电压暂态扰动识别

暂态电压扰动的识别是当前电能质量领域研究的热点,采用了无时延d-q变换进行暂态电压扰动识别,从而解决了延时60°构造对称三相电压的d-q变换的镜像扰动问题,针对无时延d-q变换易受谐波及高频噪声干扰的缺点,研究了数学形态学结合离散积分的滤波方案,用以取代传统的数字低通滤波器。在LabVIEW中的将该方案与传统数字低通滤波器进行对比,结果表明该滤波方案响应速度快,适应能力强,检测精度高,具有非常优越的综合性能。     

Generation of current mode filters using NAM expansion

Systematic synthesis method to generate a family of current mode band‐pass–low‐pass circuits based on nodal admittance matrix (NAM) expansion is given. Eight equivalent circuits are obtained, five of them are new. Each of the generated circuits uses two grounded capacitors and three grounded resistors and two balanced output current conveyor (BOCCII) or two balanced output inverting current conveyor (BOICCII) or a combination of the two types. Generation of a low input impedance current mode band‐pass–low‐pass circuits based on NAM expansion results in 16 equivalent circuits. The NAM expansion is also used to generate 32 equivalent current mode universal filters using four BOCCII or BOICCII or a combination of the two types. Copyright © 2010 John Wiley & Sons, Ltd.     

Fully reference-independent LMP decomposition using reference-independent loss factors

The decomposition of locational marginal price (LMP) under the popular DCOPF framework generally depends on the choice of the reference bus. A previous work has achieved reference independence for the overall LMP and LMP congestion component, but not all individual LMP components. This paper proposes a method to obtain a truly reference-independent LMP decomposition such that all three components of LMP at each bus will be invariant w.r.t. the choice of the system reference bus. This is achieved with loss factors based on a new AC-based distribution factor model, which depends on the network topology and the present operating condition only, but not the system reference bus. This model gives reference-independent loss prices, which can serve for a better loss hedging financial transmission rights, since the choice of reference bus will not change the loss prices. Further, this paper uses the fictitious nodal demand (FND) model to obtain loss distribution factors (LDFs). FND gives more reasonable power flows since losses should be distributed in each individual line, rather than at load buses when the load-weighted LDFs are applied. Also, the proposed reference-independent distribution factors and loss factors may have great potentials in other areas of power system analysis.     

Current-mode multiple-loop feedback filters using dual-output OTAs and grounded capacitors

A systematic method is presented for the generation, analysis and synthesis of current-mode continuous-time multiple-integrator-loop all-pole filters using dual-output operational transconductance amplifiers and grounded capacitors (DO-OTA-GC). The general theory based on a multiple-loop feedback model is formulated. A number of architectures including canonical realizations are developed, with particular emphasis on high-order configurations. A sensitivity analysis method is also given and parasitic effects on the structures are discussed. The general formulations are verified by direct analysis of the generated individual circuits. Design examples are also presented. © 1997 by John Wiley & Sons Ltd.