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随着集成电路工艺尺寸进入超深亚微米数量级,电源电压相应降低,而时钟频率却不断提高,电源网格中的动态电流变化率越来越大,使得动态电源压降(IR Drop)的问题更突出。在这种工艺按比例缩小的趋势下,去耦电容(decap电容)在电源网格中的合理布局的作用日益明显:以优化的方式放置decap电容来有效地减小电源噪声。文章介绍基于动态电源压降分析的VSDG和SOC-Encounter相结合的去耦电容优化方法学。 相似文献
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微弱电容测量电路是一种新型的电路,其是在电荷放大的基础上提出来的,在电容传感器中有着良好的应用,这种新型电路性能比较强,可以抵抗干扰,还可以降低电荷对测量分辨率的影响。这种新型电路不需要应用滤波器,而且采集信号的速度比较快,灵敏度与分辨率比较高,应用新型微弱电容测量电路,可以有效的提高电容传感器的效能。 相似文献
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本文介绍了电容法测量水箱水位的方法。用自制的平板式电容传感器进行水位测量实验,根据极板之闻介质量的变化引起电容量随之发生变化,设计了相应的测量电路,得出传感器电容值、转换频率、输出电压等多种参量的变化规律和相关实验数据。 相似文献
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从超级电容的可靠性、能量的利用率、模块规模等方面进行模组管理技术的研究。设计了超级电容器的均衡电路;解析单体电压,设计了单体电压检测电路;实现了电平转换,实现了超级电容器电压均衡控制方案。研究结果表明,相邻两个超级电容之间加入Cuk变换器均衡电路,与传统电路相比功率开关管的数目减少了一半,简化了控制的复杂度,并且节约了成本,具有良好的应用前景。 相似文献
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1,芯片功耗的主要来源C M O S电路中功耗的分布可以分为两部分,由漏电和其它静态电流导致的静态功耗和由短路电流和对负载电容充放电引起的动态功耗。这两部分中共有三种最主要的电能消耗形式:跳变损失、短路损失、漏电损失。2,跳变损失跳变损失是由电容的充放电引起的,这部分功耗在整个电路中占控制地位在0.18μm工艺水平下,这部分功耗占处理器总功耗的70～80%。图1描述了对于一个最简单的反向器电路跳变损失发生的全过程,其中Cload表示电容。图1由反向器看跳变损失的过程让我们考虑输入信号出现两次变换的一个完整的时钟周期,如图(a)。… 相似文献
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本文介绍一种闭环开关电容法电容测量电路的基本原理,数学模型及其稳定条件,其结构简单,性能优越,可在各种电容传感器测量电路中使用。 相似文献
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在电路的设计中,常利用自举电容构成的自举电路来改善电路的某些性能指标,如利用自举提高射随器的输入阻抗、利用自举提高电路增益及扩大电路的动态范围等。现就自举电路的工作原理及应用作一介绍。 相似文献
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本文简要分析了高精度非接触式电容传感器、非接触式电涡流传感器、红外光脉冲传感器的工作原理和相关电路,介绍了基于上述传感器并配合虚拟仪器开发的太阳能电池片厚度检测、电阻率测量、半导体P／N型判别系统。系统能实现对直径200mm内,厚度在150～650um,电阻率在0.3～50欧姆／cm之间的太阳能电池片的单点静态检测,和多点多方向的动态快速检测。 相似文献
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基于SMIC 0.18um CMOS工艺设计了一种高速、高精度、高线性度的采样保持电路。采用全差分带增益自举电路的高增益、高带宽运放,以及改进的带衬底电压调整的栅压自举开关,有效增加输入信号带宽并减小采样保持电路的非线性。对设计的电路进行仿真,在输入信号幅值为2VP-P,频率为47.66MHz,采样频率为100MSPS时,采样保持电路建立时间为3.606ns,建立精度达0.004%,有效位数为17.2bit,无杂散动态范围达108.5dB。 相似文献
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Insects which turn and look 总被引：1，自引：0，他引：1
G.A. Horridge 《Endeavour》1977,1(1):7-17
The compound eyes of insects and crustaceans are not uniform: regions which look in different directions become specialized for different functions. Some regions have larger facets and smaller angles between adjacent visual axes. Larger facets allow greater resolution for individual ommatidia of the eye; smaller angles between their axes allow a greater density of sampling stations. Many insects have one or more foveas, together with specialized visual habits, but even without a fovea, turning to look is probably a basic part of insect behaviour. Accurate alignment of the head axis then allows the estimation of distance without necessity for stereopsis. The form of the eye in many insects strongly suggests that they measure range over long distances by parallax rather than by binocular overlap. 相似文献
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《Journal of The Franklin Institute》2022,359(8):3517-3548
This paper is concerned with the asymptotic stabilization of discrete singular systems over a bandwidth limited digital network, when the state measurements are periodically sampled and encoded using a finite alphabet, and the control input signals are subject to finite-alphabet encoding and Denial-of-Service attacks. It is assumed that the attack signals are uniform for all sampling periods and have been identified. A dynamic controller is designed based on a restricted equivalent model of the controlled plant. Two types of finite-level quantizers are designed for encoding: uniform and logarithmic. For both types of quantizers, dynamic encoding-decoding strategies for the plant state and the control input are proposed, which exploit the controller’s state and the origin, respectively, as the quantization centers. Sufficient conditions for asymptotic stabilizability involving the sampling period, the numbers of the state and input quantization levels, the beginning time and corresponding duration of the attack signals are established by propagating reachable sets during sampling interval. Finally, several numerical examples are given to illustrate the design procedures and the efficacy of the theoretical results. 相似文献
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Droplet microfluidics is a powerful method used to characterize chemical reactions at high throughput. Often detection is performed via in-line optical readout, which puts high demands on the detection system or makes detection of low concentration substrates challenging. Here, we have developed a droplet acoustofluidic chip for time-controlled reactions that can be combined with off-line optical readout. The principle of the platform is demonstrated by the enzymatic conversion of fluorescein diphosphate to fluorescein by alkaline phosphatase. The novelty of this work is that the time of the enzymatic reaction is controlled by physically removing the enzymes from the droplets instead of using chemical inhibitors. This is advantageous as inhibitors could potentially interact with the readout. Droplets containing substrate were generated on the chip, and enzyme-coupled microbeads were added into the droplets via pico-injection. The reaction starts as soon as the enzyme/bead complexes are added, and the reaction is stopped when the microbeads are removed from the droplets at a channel bifurcation. The encapsulated microbeads were focused in the droplets by acoustophoresis during the split, leaving the product in the side daughter droplet to be collected for the analysis (without beads). The time of the reaction was controlled by using different outlets, positioned at different lengths from the pico-injector. The enzymatic conversion could be measured with fluorescence readout in a separate PDMS based assay chip. We show the ability to perform time-controlled enzymatic assays in droplet microfluidics coupled to an off-line optical readout, without the need of enzyme inhibitors. 相似文献
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M. Nikolic-Jaric S. F. Romanuik G. A. Ferrier G. E. Bridges M. Butler K. Sunley D. J. Thomson M. R. Freeman 《Biomicrofluidics》2009,3(3)
We present details of an apparatus for capacitive detection of biomaterials in microfluidic channels operating at microwave frequencies where dielectric effects due to interfacial polarization are minimal. A circuit model is presented, which can be used to adapt this detection system for use in other microfluidic applications and to identify ones where it would not be suitable. The detection system is based on a microwave coupled transmission line resonator integrated into an interferometer. At 1.5 GHz the system is capable of detecting changes in capacitance of 650 zF with a 50 Hz bandwidth. This system is well suited to the detection of biomaterials in a variety of suspending fluids, including phosphate-buffered saline. Applications involving both model particles (polystyrene microspheres) and living cells—baker’s yeast (Saccharomyces cerevisiae) and Chinese hamster ovary cells—are presented. 相似文献
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基于目标宽度特征的脉间跳频雷达距离精确成像 总被引：2，自引：0，他引：2
根据雷达目标的宽度特征 ,提出了目标检测窗口内雷达信号的逆Chirp z变换局部成像处理方法 .利用有限的输入数据长度 ,有效提高目标局部距离像的采样分辨率 ,获得更精确的距离像 .与传统的数据长度补零逆傅里叶变换方法相比 ,在相同的采样分辨率条件下 ,该方法能有效减小计算量 .仿真实验结果与理论分析相符合 ,证明了该方法的有效性 . 相似文献
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Wenbo Pang Xu Cheng Haojie Zhao Xiaogang Guo Ziyao Ji Guorui Li Yiming Liang Zhaoguo Xue Honglie Song Fan Zhang Zheng Xu Lei Sang Wen Huang Tiefeng Li Yihui Zhang 《国家科学评论(英文版)》2020,7(2):342
The manufacture of 3D mesostructures is receiving rapidly increasing attention, because of the fundamental significance and practical applications across wide-ranging areas. The recently developed approach of buckling-guided assembly allows deterministic formation of complex 3D mesostructures in a broad set of functional materials, with feature sizes spanning nanoscale to centimeter-scale. Previous studies mostly exploited mechanically controlled assembly platforms using elastomer substrates, which limits the capabilities to achieve on-demand local assembly, and to reshape assembled mesostructures into distinct 3D configurations. This work introduces a set of design concepts and assembly strategies to utilize dielectric elastomer actuators as powerful platforms for the electro-mechanically controlled 3D assembly. Capabilities of sequential, local loading with desired strain distributions allow access to precisely tailored 3D mesostructures that can be reshaped into distinct geometries, as demonstrated by experimental and theoretical studies of ∼30 examples. A reconfigurable inductive–capacitive radio-frequency circuit consisting of morphable 3D capacitors serves as an application example. 相似文献
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介绍了一种高性能CMOS采样/保持电路，在0.35-μm工艺、3.3-V电源和18-mW功耗下，实现了50-MHz采样频率，输入直到奈奎斯特频率仍能达到10位精度的要求。电路采用全差分结构、底极板采样、栅压自举开关技术、增益自举的折叠共源共栅跨导核心运算放大器和钳制共模电平的电平控制放大器。 相似文献
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为了优化低压电网的电能质量,研制出了低压有源滤波和动态无功补偿装置,能够提供从感性到容性连续、平滑、动态、快速的无功功率补偿,对13次及以下的谐波抑制效果显著;将该装置应用到兖矿东华工业园铆焊车间既保障了现场生产设备正常运行,又大幅度降低了电能损耗,对建设绿色电网具有重要的现实意义。 相似文献