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981.
982.
提出了一个基于0.18μm标准CMOS工艺实现的四级差分环形压控振荡器.全差分环形压控振荡器采用带对称负载的差分延时单元.仿真结果表明,压控振荡器的频率范围在最坏情况为0.21~1.18GHz;偏离中心频率10MHz情况下,压控振荡器的相位噪声为-118.13dBc/Hz; 1.8V电源电压下,中心频率为600MHz时,压控振荡器的功耗仅有4.16mW;版图面积约为0.006mm2.可应用于锁相环和频率综合器设计中. 相似文献
983.
984.
Sucheng Liu Luowei Zhou Xiaodong Liu Weiguo Lu 《International Journal of Electronics》2013,100(10):1421-1432
A high efficiency linear power amplifier is introduced based on the idea of Switch-Linear Hybrid (SLH) power conversion. The SLH power amplifier developed from the conventional class B power amplifier, while the class B configuration power unit in the SLH power amplifier is fed by a dynamic switching power supply, not the usual constant DC power supply. Thus, the efficiency of the class B configuration power unit in SLH power amplifier can be greatly improved. By combining linear power amplifier with switching power supply, the SLH power amplifier has synthetic performance of high fidelity, high efficiency and excellent dynamic characteristics. In this article, analysis of SLH power amplifier is performed, especially focusing on its linear power unit which is the core of SLH power amplifier. Design considerations are also presented parallel with the analysis. Both the theoretical analysis and experimental results verify the validity of SLH power amplifier. 相似文献
985.
Mohammad Rashtian Ali Mohammad Afshin Hemmatyar Omid Hashemipour 《International Journal of Electronics》2013,100(12):1729-1737
Thermal noise is one of the most important challenges in analogue integrated circuits design. This problem is more crucial in switched-capacitor (SC) filters due to the aliasing effect of wide-band thermal noise. In this article, a new simple method is proposed for estimating the power spectrum density of output thermal noise in SC filters, which have acceptable accuracy and short running time. In the proposed method, first using HSPICE simulator, accurate value of accumulated sampled noise on sampler capacitors in each clock state is achieved. Next, using difference equations of the SC filter, frequency response of the SC filter is shaped by time domain analysis. Based on the proposed method, a SC low-pass filter and a second-order SC band-pass filter are analysed. The results are validated by comparing to the previously measured data. 相似文献
986.
In this article, two consecutive augmenting transistor P-channel metal oxide semiconductor (ATPMOS) configurations are proposed. These two ATPMOS configurations (ST ATPMOS and DT ATPMOS) are implemented on a 4 × 1 (multiplexer) mux circuit. Leakage power dissipation, dynamic power dissipation and delay performance parameters are calculated for both (ST ATPMOS and DT ATPMOS) ATPMOS configurations-based 4 × 1 mux circuits at different values of transistor’s width. Due to simulation, it is realised that the leakage power dissipation and dynamic power dissipation are reduced and delay is improved (delay is reduced) in the DT ATPMOS configuration-based mux circuit compared to the ST ATPMOS configuration-based mux circuit. The whole simulation process was carried out in 45-nm technology. The circuits were operated at 1-V power supply. 相似文献
987.
以设计输出电流为700 mA,静态电流为50μA,芯片面积为1.5 mm×2.0 mm的LDO线性稳压器为目标,提出的LDO电路利用基准电路的输出直接作为芯片的输出,用基准电路所固有的跨导放大器对输出进行检测并反馈至单级放大器,放大后输出至功率管的基极,控制功率管输出额定的电压和电流。无需冗余的误差放大器,使得环路补偿极为简单,不存在传统LDO的补偿难题。在电路上把传统LDO电路所需各个模块的功能糅合到了一个较为简单的电路中,大大减小了芯片面积,并且减小了静态电流。对电路进行了仿真分析并采用2μm 36 V Bipolar工艺生产实现,流片后的测试结果表明该芯片实现了大电流,微功耗,小体积的特性。 相似文献
988.
F. F. Wu A. Monticelli 《International Journal of Electrical Power & Energy Systems》1983,5(4):222-235
A critical review of various external network modelling methods for online security analysis is presented. Motivations and derivations of the methods are discussed. Each method is assessed from the point of view of accuracy and of computational and load-flow compatibility. A unified approach to external network modelling which encompasses the desired features of different methods is proposed. 相似文献
989.
Secondary-arc suppression is necessary for successful fast, multiphase reclosing on UHV lines. Installation of a shunt reactor is one of the most effective methods of rapidly extinguishing the secondary arc. For multiphase reclosing on untransposed double-circuit UHV lines, a zero-sequence compensated balanced shunt reactor cannot suppress the secondary arc sufficiently. This is because of the imbalance in electrical couplings among phases. A zero-sequence compensated unbalanced shunt reactor is proposed to compensate for the imbalance in the electrostatic couplings. The effects of this reactor on suppressing the secondary arc can easily be analysed by the introduction of phase-to-phase compensation parameters. Such parameters can be used to decide on the optimum shunt reactor for secondary-arc extinction. 相似文献
990.
D.P. Clancy G. Gross F.F. Wu 《International Journal of Electrical Power & Energy Systems》1983,5(2):101-114
The development of a solution method and computer program for the evaluation of multiarea reliability is reported. An interconnected power system is modelled as a capacitated network with probabilistic arc capacities. The proposed solution method consists of an analytic state space decomposition phase and a Monte-Carlo simulation phase. An optimization problem is solved to minimize the total computational time for the two phases. The solution of the optimal mix problem determines the termination of the decomposition phase and the size of sample for the Monte-Carlo phase. A new reliability index, the inadequate transfer capability, is introduced. This measure indicates the relative effectiveness of either increasing existing capacities or opening new interconnections between two areas. The proposed method has been incorporated into a computationally efficient production grade software package, called Remain (Reliability Evaluation of Multiarea Interconnections). The application of Remain to a seven-area example for planning-system enhancement is given. Computational-times data is also presented. 相似文献