Results 171 to 180 of about 4,146 (226)

Microwave plasma varactors

1966 International Electron Devices Meeting, 1966
A low-loss, low-noise plasma varactor has been developed. This is a variable microwave reactance produced by means of a low pressure, highly efficient gas discharge. This device compares favorably with ferrite or semiconductor devices as far as rf losses and average rf power handling capability are concerned. A low-loss phase shifter has been developed
J.Y. Wada, R.C. Knechtli, B.J. Forman
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Nonlinear effects in varactor-tuned resonators

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2004
This paper describes the effects of RF power level on the performance of varactor-tuned resonator circuits. A variety of topologies are considered, including series and parallel resonators operating in both unbalanced and balanced modes. As these resonators were designed to produce oscillators with minimum phase noise, the initial small signal ...
Everard, J., Liang, Z.
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Excess capacitance of ZnO-Au varactors

Applied Physics A Solids and Surfaces, 1987
Doped ZnO single crystals were deposited with gold and indium in 1×10−8 Torr vacuum. The lithium-doped ZnO single crystals and the gold interface revealed not only a Schottky diode but also varactor characteristics. TheI-V andC-V characteristics of ZnO:Li-Au devices were determined in the 0–140 mV and 0–1.5 V ranges.
�. Dalay, S. Akpinar
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The space-charge varactor

Solid-State Electronics, 1965
Abstract A simplified theory and design analysis is presented for the space-charge varactor. Under conditions of forward and reverse bias, the device possesses constant but different values of incremental capacitance, and switches rapidly from one state to the other as the applied voltage changes polarity.
D.P. Howson, B. Owen, G.T. Wright
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On the use of MOS varactors in RF VCOs

IEEE Journal of Solid-State Circuits, 2000
This paper presents two 1.8 GHz CMOS voltage-controlled oscillators (VCOs), tuned by an inversion-mode MOS varactor and an accumulation-mode MOS varactor, respectively. Both VCOs show a lower power consumption and a lower phase noise than a reference VCO tuned by a more commonly used diode varactor.
Pietro Andreani, Sven Mattisson
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Varactor diode measurements

Radio and Electronic Engineer, 1966
A comparison has been made of the ‘relative impedance’ and ‘transmission’ techniques of measuring the small-signal parameters of varactor diodes. Relative-impedance measurements have been made at u.h.f. and X-band and transmission measurements at X-band.
F.J. Hyde, S. Deval, C. Toker
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Physical Device Modeling of a Varactor Diode

IEEE Transactions on Magnetics, 2004
Starting with the recipe for the fabrication process of a silicon p-n junction varactor diode, the semiconductor device equations are solved using the finite-element method. The capacitance of the reverse biased diode is extracted using the junction depletion width which is quantified by introducing a depletion factor.
Masidlover, Alexander R., Gibson, Andrew A P   +1 more
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Design parameters for varactor frequency triplers using idealized punchthrough varactors

Proceedings of the IEEE, 1976
This letter gives the design parameters for a varactor frequency tripler using idealized punchthrough varactors. It is shown that there are many operating points that give approximately the same efficiency, and that the matching network will determine which one is chosen.
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The Island-Gate Varactor—A High-Q MOS Varactor for Millimeter-Wave Applications

IEEE Microwave and Wireless Components Letters, 2009
A new accumulation MOS varactor with island-shaped poly gate layout is proposed to improve the quality factor ( Q-factor) at high frequency, which can be readily employed for CMOS-based millimeter-wave applications. Measured results up to 67 GHz show significant improvements in the Q-factor and the series resistance Rs over the conventional multi ...
null Yongho Oh, null Sooyeon Kim, null Seungyong Lee, null Jae-Sung Rieh   +3 more
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A tunable bandpass patch filter with varactors

2010 IEEE MTT-S International Microwave Symposium, 2010
This paper presents a miniaturized tunable bandpass patch filter using varactors. The filter is conceived with a triple-mode circular patch resonator with four slots, where the varactors were connected. The extracted equivalent model, the varactors assembly configuration and their biasing are presented.
A., Serrano, T.-P., Vuong, F. S., Correra, Ferrari, Philippe   +3 more
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