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31.
Design challenges of a 65 nm CMOS stacked folded differential PA structure for mobile communications
Yohann Luque Nathalie Deltimple Eric Kerhervé Didier Belot 《Analog Integrated Circuits and Signal Processing》2011,66(2):155-162
In this paper, a novel phase-locked loop (PLL) architecture with multiple charge pumps, which is used to design a fast-locking
PLL and a low-phase-noise PLL, is proposed. The effective capacitance and resistance of the loop filter in terms of voltage
is scaled up/down according to the locking status by controlling the magnitude and direction of the charge pump current. Two
PLLs, one with a fast-locking characteristic and the other with a low-phase-noise characteristic, are designed and fabricated
in a 0.35-μm CMOS process based on the proposed architecture. The fast-locking PLL has a locking time of less than 6 μs and
a phase noise of −90.45 dBc/Hz at 1 MHz offset. The low-phase-noise PLL has a locking time of 25 μs, a phase noise of −105.37 dBc/Hz
at 1 MHz offset, and a reference spur of −50 dBc. Both PLLs have an 851.2 MHz output frequency. 相似文献
32.
Sverine Gomes Nathalie Trannoy Philippe Grossel Franoise Depasse Claudine Bainier Daniel Charraut 《International Journal of Thermal Sciences》2001,40(11):1794
The used Scanning Thermal Microscopy (SThM) probe is a thin Pt resistance wire acting as a heat source and as a detector simultaneously. Its energetic balance is investigated by the study of the temperature profile along the probe. A theoretical approach of the measurement, based on this investigation, is then proposed. Simulations with this modelling are shown to predict how the heat, electrically produced in the probe, is dissipated in the probe-sample system. In particular, it is shown that the steady-state of conduction losses to the thermal element support varies versus the thermal conductivity of the sample and can lead to bad interpretations of the measurement. 相似文献
33.
Yong‐Ning Zhou Mahsa Sina Nathalie Pereira Xiqian Yu Glenn G. Amatucci Xiao‐Qing Yang Frederic Cosandey Kyung‐Wan Nam 《Advanced functional materials》2015,25(5):696-703
Searching high capacity cathode materials is one of the most important fields of the research and development of sodium‐ion batteries (SIBs). Here, we report a FeO0.7F1.3/C nanocomposite synthesized via a solution process as a new cathode material for SIBs. This material exhibits a high initial discharge capacity of 496 mAh g?1 in a sodium cell at 50 °C. From the 3rd to 50th cycle, the capacity fading is only 0.14% per cycle (from 388 mAh g?1 at 3rd the cycle to 360 mAh g?1 at the 50th cycle), demonstrating superior cyclability. A high energy density of 650 Wh kg?1 is obtained at the material level. The reaction mechanism studies of FeO0.7F1.3/C with sodium show a hybridized mechanism of both intercalation and conversion reaction. 相似文献
34.
A multiparameter wearable physiologic monitoring system for space and terrestrial applications. 总被引:4,自引:0,他引:4
Carsten W Mundt Kevin N Montgomery Usen E Udoh Valerie N Barker Guillaume C Thonier Arnaud M Tellier Robert D Ricks Robert B Darling Yvonne D Cagle Nathalie A Cabrol Stephen J Ruoss Judith L Swain John W Hines Gregory T A Kovacs 《IEEE transactions on information technology in biomedicine》2005,9(3):382-391
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described. 相似文献
35.
36.
Sofiane Aloui Nicolas Delaunay Eric Kerherve Nathalie Deltimple Robert Plana Didier Belot 《Analog Integrated Circuits and Signal Processing》2012,70(2):203-211
A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the linearity, the PA is designed under class A biasing to have an output compression point (OCP1) close to its saturated Power (P sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA offers a P sat of 8.3 dBm, an OCP1 of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm2 with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode. 相似文献
37.
The effects of static, alternating and dynamic stress conditions on the degradation rate of 0.8μm n- and p-channel LDD MOS transistors have systematically been investigated and compared. The shifts of the threshold voltage, transconductance, linear drain current and charge pumping current were used to monitor the transistor degradation. The results suggest that the aging induced by a dynamic stress cannot be directly explained with static stress models, essentially because it is highly dependent on a larger number of parameters (biases and durations of the top and bottom levels of the pulses, transient times). The correlation of static and dynamic stresses also clarifies the degradation mechanisms, in particular the role of hot holes in the generation of interface states. 相似文献
38.
Florence Bonnet-Magnaval Leïla Halidou Diallo Valrie Brunchault Nathalie Laugero Florent Morfoisse Florian David Emilie Roussel Manon Nougue Audrey Zamora Emmanuelle Marchaud Florence Tatin Anne-Catherine Prats Barbara Garmy-Susini Luc DesGroseillers Eric Lacazette 《International journal of molecular sciences》2022,23(1)
39.
Jean‐Michel Savoie Nathalie Minvielle Michèle L Largeteau 《Journal of the science of food and agriculture》2008,88(6):970-975
BACKGROUND: Agaricus bisporus is the premier cultivated edible mushroom but is usually considered to be of lesser value nutritionally and medicinally compared with other cultivated mushrooms. The objective of this study was to investigate the radical‐scavenging properties of methanolic extracts and the free radical‐processing enzyme activities of water extracts from A. bisporus fruit bodies. Analyses were performed on total fruit bodies from three strains and on separated stipe, cap and gills from one strain, all cultivated experimentally under the same conditions. RESULTS: EC50 values of scavenging ability on 1,1‐diphenyl‐2‐picrylhydrazyl radicals (DPPH?), scavenging ability on 2,2‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cations (ABTS?+) and reducing power of methanolic extracts from total fruit bodies ranged between 1.7 and 5.0 and were 1.1–1.9 times higher in a white hybrid than in two wild strains, cream and brown. The gills exhibited higher antioxidant activities relative to the stipe and cap. In water extracts, glutathione peroxidase activities were up to eight times higher than glutathione reductase activities and no difference was observed between strains. Catalase activity was highest in the brown wild strain. The only significant differences in free radical‐processing enzymes between the three parts of the mushroom were higher catalase activity in the gills and lower glutathione reductase activity in the stipe. CONCLUSION: The radical‐scavenging properties of the button mushroom are comparable to those of other edible mushrooms and dependent on the strain and on the section of the fruit body. Copyright © 2008 Society of Chemical Industry 相似文献
40.