共查询到20条相似文献,搜索用时 15 毫秒
1.
We present a new approach to model nonquasi-static (NQS) effects in a MOSFET in a small-signal situation. The model derived here is based on the large-signal NQS model previously proposed. The derivation of the small-signal model is presented. The small-signal parameters obtained with this model prove to be accurate up to very high frequencies. An excellent match between the new model and device simulation results has been observed even when the frequency is many times larger than the cutoff frequency. 相似文献
2.
Byungcho Choi Sung-Soo Hong Hyokil Park 《Industrial Electronics, IEEE Transactions on》2001,48(1):136-142
A large-signal average model for the controlled on-time boost power-factor-correction (PFC) circuit is developed and subsequently linearized, resulting in a small-signal model for the PFC circuit. AC analyses are performed using the small-signal model, revealing new results on the small-signal dynamics of the PFC circuit. The analysis results and model predictions are confirmed with experimental measurements on a 200-W prototype PFC circuit 相似文献
3.
This letter presents a novel small-signal model extraction procedure which determines intrinsic and extrinsic base-collector capacitance (Cbci and Cbex, respectively) directly from S-parameter data. The procedure utilizes physical assumptions shout the bias dependence of small-signal parameters. The model is validated on several InGaP/GaAs HBTs with different layouts, and the extraction results are discussed. The small-signal model is physical, produces excellent S-parameter fits, and may be used to derive a compact large-signal model 相似文献
4.
The pulse-width-modulation (PWM) buck converter with synchronous rectifiers operating at light load is usually modeled by its continuous conduction mode (CCM) model. However, the actual power-stage small-signal control-to-output response shows a different behavior from what the traditional CCM model predicts, specifically, more damping around the double-pole frequency, instead of more resonance. This paper presents a modified small-signal light-load model for a synchronous buck converter. The developed model accurately predicts the actual small-signal behavior of a PWM converter at light load. The derived averaged switch model for light load can also be used for the small-signal models of the other basic PWM converters operating in CCM at light load. 相似文献
5.
Sung-Soo Hong 《Electronics letters》1999,35(1):10-11
The conventional small-signal circuit model in the discontinuous conduction mode (DCM) shows large discrepancies at high frequencies. A new unified small-signal circuit model of the pulsewidth modulation (PWM) switch including inductor in the DCM is proposed to overcome the inaccuracy of the conventional small-signal circuit model 相似文献
6.
The small-signal model for a multiple-output forward power converter with weighted voltage control is derived. The effects of the weighting factors on the small-signal behavior are investigated. In addition, the small-signal characteristics of weighted voltage control are compared with the characteristics of a multiple-output power converter with coupled output-filter inductors. Finally, the effects of weighted voltage control on the small-signal characteristics of the converter with coupled inductors are examined. Based on the analysis, the design procedure for loop compensation is presented. The small-signal model and the design procedure are verified on an experimental two-output forward power converter 相似文献
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8.
A simple non-quasi-static small-signal equivalent circuit model is derived for the ideal MOSFET wave equation under the gradual channel approximation. This equivalent circuit represents each Y -parameter by its DC small-signal value shunted by a (trans) capacitor in series with a charging (trans) resistor. A large-signal model for the intrinsic MOSFET is derived by first implementing this RC topology in the time domain. Modified state equations are then introduced to enforce charge conservation. Transient simulations with this approximate large-signal model yield results that are compared with reported exact numerical analysis for the long channel MOSFET for a wide range of bias conditions. This unified small- and large-signal model applies to both the three- and four-terminal intrinsic MOSFET in the region of the channel where the gradual channel approximation is applicable. A non-quasi-static small-signal equivalent circuit for the velocity-saturated MOSFET wave equation is also reported 相似文献
9.
A reduced-order (RO) small-signal model of three-phase pulse-width-modulation (PWM) rectifiers is proposed. By combining the PWM switch model and equivalent multimodule model techniques in DC-DC converters, a three-phase rectifier can be modeled as a DC-DC converter with equivalent power capability and small-signal characteristics. This model reduces the system order to two and greatly simplifies the control design and system analysis of three-phase converters. In this paper, the proposed model is also used for control design and for system interaction analysis on the three-phase interface of a boost rectifier. The RO model is verified with the d-q model, switching-model simulation, and experimental results 相似文献
10.
Zhu G. Wei H. Kornetzky P. Batarseh I. 《Power Electronics, IEEE Transactions on》1999,14(6):1142-1148
In this paper, a small-signal model for a new single-switch single-stage switched-mode power-factor-correction (PFC) converter is presented. The model is obtained by applying the small-signal perturbation technique to the circuit equations derived from the state-space averaging method. By applying the perturbation and averaging techniques over one switching cycle, the DC and small-signal equivalent circuit representations of this converter are derived. The result shows that this converter exhibits the transfer characteristics of a second-order low-pass system for the output-to-input transfer function and that of a combined second-order low-pass and band-pass system for the output-to-control transfer function. The validity of the proposed mathematical model was verified by the given experimental results for a specified design example 相似文献
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12.
The operation of micron and submicron GaAs MESFETs under high-speed transient and high-frequency small-signal conditions is analyzed using a two-dimensional model. The effects of displacement currents, dipole due to negative differential mobility or current continuity, and two-dimensional transport are emphasized. The origin of delay effects, such as the phase delay incorporated in small-signal models, is explored in order to relate it to the behavior under switching conditions. Broadband expressions for the extraction of a complete small-signal model are presented. Using the expressions derived, the variation of model elements with frequency and the effect of this on the unilateral gain of the device are studied 相似文献
13.
Aarts A.C.T. Smit G.D.J. Scholten A.J. Klaassen D.B.M. 《Electron Devices, IEEE Transactions on》2008,55(6):1424-1432
In this paper, a small-signal MOSFET model is described, which takes the local effects of both velocity saturation and transverse mobility reduction into account. The model is based on the PSP model and is valid for both quasi-static and nonquasi-static (NQS) operations. Recently, it has been found that, in the presence of velocity saturation, the low-frequency capacitances cannot be determined from the Ward-Dutton charge-partitioning scheme. By use of the small-signal model developed in this paper, it is demonstrated that, in the presence of velocity saturation, no terminal drain and source charges exist, from which the capacitances can be derived. The small-signal model enables the determination of the correct capacitive behavior in the presence of velocity saturation. Furthermore, it is demonstrated how the small-signal model can be used to determine the number of collocation points needed in the large-signal NQS PSP model. Finally, inclusion of the local variation of mobility reduction due to the vertical electrical fields provides insight into the approach commonly applied in compact modeling, where these fields are replaced by global ones depending on the terminal voltages only. 相似文献
14.
《Electron Devices, IEEE Transactions on》1974,21(8):469-479
A quasi-static large-signal model of an IMPATT diode with general doping profile is derived. The numerical solution of this model has been implemented in a Fortran IV program which executes economically. This model has been used to analyze large-and small-signal admittances of GaAs double-drift and quasi-Read IMPATT diodes. The small-signal results are in good agreement with calculations done using a linearized small-signal model. The large-signal calculations exhibit power and efficiency saturation when reasonable values of parasitic resistance are included and are in good agreement with experimental GaAs diode performance. The generalized quasi-static formulation simplifies analysis of IMPATT structures with arbitrary doping profiles, specifically those with distributed avalanche zones, by providing the correspondence between these devices and the Read diode model. 相似文献
15.
Seonghearn Lee Hyun Kyu Yu 《Electronics letters》1999,35(17):1406-1407
The serious problem caused by the extraction of MOSFET parameters using a conventional small-signal model is addressed. It is overcome by developing an improved small-signal model where the drain-bulk junction capacitance is connected to the external source. The model is validated by finding model parameters exhibiting frequency independence while maintaining their physical character, using a modified direct extraction approach 相似文献
16.
《Microwave Theory and Techniques》1976,24(11):752-758
A circuit model has been developed to describe a class of commonly used waveguide cavities for V-band IMPATT oscillators and amplifiers. Calculated results based on this model used in conjunction with theoretical small-signal IMPATT characteristics have shown good qualitative agreement with experimental data. Detailed characterization of a small-signal V-band IMPATT amplifier and a mechanical tuned oscillator are presented, and the predicted performance is compared with measurements. 相似文献
17.
《Industrial Electronics, IEEE Transactions on》2009,56(3):706-717
18.
利用改进的小信号模型对采用100nmInAlAs/InGaAs/InP工艺设计实现的PHEMTs器件进行建模, 并设计实现了一款W波段单片低噪声放大器进行信号模型的验证。为了进一步改善信号模型低频S参数拟合差的精度, 该小信号模型考虑了栅源和栅漏二极管微分电阻, 在等效电路拓扑中分别用Rfs和Rfd表示.为了验证模型的可行性, 基于该信号模型研制了W波段低噪声放大器单片.在片测试结果表明:最大小信号增益为14.4dB@92.5GHz, 3dB带宽为25GHz@85-110GHz.而且, 该放大器也表现出了良好的噪声特性, 在88GHz处噪声系数为4.1dB, 相关增益为13.8dB.与同频段其他芯片相比, 该放大器单片具有宽3dB带宽和高的单级增益. 相似文献
19.
An approach to the mathematical simulation of small-signal current gains (alphas) versus frequency that respects Fulop's measuring procedure is proposed, using an arrangement close to the real measuring circuit. For this purpose, an exact 1-D mathematical model is used. The dependence of small-signal alphas on the anode current of a high power thyristor (GTO) was found to be in agreement with measurements for low anode-to-cathode voltage 相似文献
20.
The small-signal behavior of a frequency controlled resonant converter is modeled as an equivalent pulsewidth modulation (PWM) converter. By this model, a recently developed simulation algorithm for PWM converter is modified to simulate both the open-loop and closed-loop small-signal behavior. Experimental results show that this approach is accurate and efficient. 相似文献