Home About us Contact
|
Home About us Contact | ||
|
|
||
Low-power Consumption (low-power + consumption)
Selected AbstractsCompact CMOS implementation of a low-power, current-mode programmable cellular neural network,INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 3 2001L. Ravezzi Abstract We report on the design and characterization of a full-analog programmable current-mode cellular neural network (CNN) in CMOS technology. In the proposed CNN, a novel cell-core topology, which allows for an easy programming of both feedback and control templates over a wide range of values, including all those required for many signal processing tasks, is employed. The CMOS implementation of this network features both low-power consumption and small-area occupation, making it suitable for the realization of large cell-grid sizes. Device level and Monte Carlo simulations of the network proved that the proposed CNN can be successfully adopted for several applications in both grey-scale and binary image processing tasks. Results from the characterization of a preliminary CNN test-chip (8×1 array), intended as a simple demonstrator of the proposed circuit technique, are also reported and discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source] Design of a high-efficiency hydrofoil through the use of computational fluid dynamics and multiobjective optimizationAICHE JOURNAL, Issue 7 2009N. Spogis Abstract A computational fluid dynamics (CFD) model is proposed, based on ANSYS-CFX tools coupled to optimization models inside the commercial optimization software modeFRONTIER in order to obtain an optimal design of a high-efficiency impeller for solids suspension. The analysis of impeller shape performance was carried out using the shear-stress transport (SST) turbulence model with streamline curvature correction. This turbulence model combined the advantages of the ,,, and ,,, models, ensuring a proper relation between turbulent stress and turbulent kinetic energy, allowing an accurate and robust prediction of the impeller blade flow separation. The multiple frames of reference and the frozen rotor frame change models were used for the rotor/stator interaction inside the mixing vessel. The optimization procedure used seven design variables, two nonlinear constraints and two objective functions. The objective functions chosen (among many other possible options) to evaluate the impeller performance were the maximum solid distribution throughout the vessel (homogeneous suspension) reflected by a low variance between local solid concentration and average solid concentration inside the vessel and the higher pumping effectiveness, which was defined as the quotient of the flow and power numbers. The first objective function searches for impeller configurations able to provide good solid suspension, since it aims to achieve homogeneous suspension. The second objective function aims to reduce power consumption for a high-pumping capacity of the impeller. These criteria were considered enough to characterize the optimized impeller. Results indicated that the optimized impeller presented an increase of the pumping impeller capacity and homogeneous solid suspension with low-power consumption, especially when compared with the PBT 45° impeller. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Low-voltage/low-power 7-GHZ transformer-coupled current-reused CMOS QVCO with wide tuning rangeMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2010Yan-Ru Tseng Abstract In this article, we report the design of a transformer-coupled current-reused quadrature voltage-controlled oscillator (QVCO) having low-voltage operation, low-power consumption, and a wide tuning range. An improved trifilar transformer that is fabricated by symmetrically interlacing two half circle secondary coils between the turns of the primary coil is proposed to provide a higher magnetic coupling factor. A QVCO integrated with such a trifilar transformer is implemented using 0.18-,m RF CMOS technology. When the QVCO is operated at a supply voltage of 1V at 7.263 GHz, the measured phase noise is ,111.4 dBc/Hz at a 1-MHz offset. Further, the QVCO core draws only 1.58 mW. The total tuning range is ,510 MHz over the whole tuning range (from 0 to 1.8 V). The calculated figure of merit is 186.6 dB and the power-frequency-tuning-normalized factor is ,9.4 dB. As compared to the reported data in a previous study, a 28.2% reduction in power consumption and a 54.5% increase in tuning range can be achieved. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:797,801, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25058 [source] Multigigabit CMOS limiting amplifier and VCSEL driver arrays for parallel optical interconnectsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2006Sae-Kyoung Kang Abstract Limiting amplifier and VCSEL driver arrays for parallel optical interconnects operating at 8 Gb/s are presented, which are designed and fabricated in a Si-based 0.18-,m CMOS technology for the single chip integration with low-power consumption. The limiting amplifier array showed a differential gain of 26 dB, a ,3-dB bandwidth of 6.8 GHz, and a crosstalk of ,32 dB between channels. For the VCSEL driver array, it showed a differential gain of 25 dB, a ,3-dB bandwidth of 6.3 GHz, and crosstalk of ,26 dB between channels. The power dissipation per channel of the limiting amplifier and the VCSEL driver are 45 and 120 mW, respectively. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1656,1659, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21691 [source] | ||||||||||