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901.
DiaaEldin Khalil Muhammad Khellah Yehea Ismail Vivek De 《Microelectronics Journal》2009,40(11):1523-1530
In this paper, an accurate approach for estimating the dynamic stability of static random access memory (SRAM) is proposed. The conventional methods of SRAM stability estimation suffer from two major drawbacks: (1) using static failure criteria, such as SNM, which does not capture the transient and dynamic behavior of SRAM operation, and (2) using quasi-Monte-Carlo simulation, which approximates the failure distribution, resulting in large errors at the tails where the desired failure probabilities exist. These drawbacks are eliminated by employing accurate simulation-based dynamic failure criteria along with a new distribution-independent, Most-probable-failure-point search technique for accurate probability calculation. Compared to previously published techniques, the proposed dynamic stability technique offers orders of magnitude improvement in accuracy. Furthermore, the proposed dynamic stability technique enables the correct evaluation of stability in real operation conditions and for different dynamic circuit techniques, such as dynamic write back, where the conventional methods are not applicable. 相似文献
902.
苏存勖 《光纤与电缆及其应用技术》2009,(3):32-34
介绍了宽带RF信号直接光强度调制光发射机与光接收机的原理,分析了光传输系统中的载噪比、动态范围等重要指标。 相似文献
903.
Alexander Belyaev 《Pramana》2009,72(1):143-160
Large Hadron Collider (LHC) has a great chance to finally reveal supersymmetry which remains a compelling theory for over
30 years in spite of lack of its discovery. It might be around the corner the present LHC era with sensitive dark matter search
experiments and international linear collider hopefully coming up in the near future.
相似文献
904.
Sangchoon Kim 《ETRI Journal》2011,33(6):949-952
In this letter, a simplified suboptimum receiver based on soft‐limiting for the detection of binary antipodal signals in non‐Gaussian noise modeled as a generalized normal‐Laplace (GNL) distribution combined with Gaussian noise is presented. The suboptimum receiver has low computational complexity. Furthermore, when the number of diversity branches is small, its performance is very close to that of the Neyman‐Pearson optimum receiver based on the probability density function obtained by the Fourier inversion of the characteristic function of the GNL‐plus‐Gaussian distribution. 相似文献
905.
SiC MESFET反向截止漏电流的研究 总被引:2,自引:0,他引:2
给出了一种减小SiC MESFET栅漏反向截止漏电流的工艺方法,通过采用LPCVD淀积厚SiO2和高温氧化工艺,使器件的性能得到一定的提升.从实验数据看出,器件在S波段工作时,器件的反向截止漏电流大幅度下降,且分散性得到改善,其功率附加效率和功率增益也分别提高了10%和1.5 dB.该方法充分发挥了SiC材料能形成自身氧化层的优势,结合Si工艺的特点,减小了氧化层的缺陷,并在一定程度上减小了器件的寄生电容. 相似文献
906.
A unified noise figure expression incorporating the thermal noise and flicker noise has been proposed for active CMOS mixers. Based on the derived conversion functions with output resistance effect, the noise transforming factors for different stages are numerically computed to rigorously describe the noise output. The subthreshold conductance has also been taken into account by utilizing the latest continuous noise model and the simplified MOSFET I-V model. As a result, the frequency-dependent characteristic of noise expression is of competency for explaining the flicker noise mechanism, thus can be directly applied to active CMOS mixers with any IF characteristics. And good agreement is obtained between simulations and measurements. 相似文献
907.
该次试验的目的是为了开发出85℃3000小时这种新的系列的焊片式铝电解电容器。为此,对该系列选取了最小电压200V的小容量和大容量,及最大电压450V的小容量和大容量的产品分别进行了设计和开发。开发过程中对阳极箔,阴极箔,电解纸,电解液等原材料进行了分析比较,并将四种设计分别做成产品并测试最薄弱的环节85℃3000小时的纹波电流试验,结果表明该系列的设计能很好地满足电性能要求。 相似文献
908.
rents from 1 pA to 300 nA can be detected with a maximum nonlinearity of 0.3% over the full scale. 相似文献
909.
In this paper, the long-term reliability of all monolithic 1.55-μm etched-mesa vertical cavity surface emitting lasers (VCSELs) with tunnel junction is investigated via high-temperature storage tests and accelerated life tests. Characteristic variations depend on the operating conditions are examined via the threshold current, the optical output power, and the dark current. The median device lifetime is extrapolated and the activation energy of the VCSELs is calculated based on the reliability testing results. In addition, the degradation mechanism of the tested VCSELs is analyzed using the correlation between the current-voltage characteristics (I-V) and the device lifetime. From these results, the long-term reliability of the VCSEL test structures for high-speed optical communication systems can be determined and the device parameters, such as dark current, can be used as a monitoring factor for estimating reliability of the VCSELs. 相似文献
910.
EDOT‐diketopyrrolopyrrole copolymers for high bulk hole mobility and near infrared absorption
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Christian J. Mueller Chetan R. Singh Mukundan Thelakkat 《Journal of Polymer Science.Polymer Physics》2016,54(6):639-648
To obtain novel low‐bandgap materials with tailored hole‐transport properties and extended absorption, electron rich 3,4‐ethylenedioxythiophene is introduced as a comonomer in diketopyrrolo[3,4‐c]pyrrole copolymers with different aryl flanking units. The polymers are characterized by absorption and photoluminescence spectroscopy, dynamic scanning calorimetry, cyclic voltammetry, and X‐ray diffraction. The charge transport properties of these new materials are studied carefully using an organic field effect transistor geometry where the charge carriers are transported over a narrow channel at the semiconductor/dielectric interface. These results are compared to bulk charge carrier mobilities using space‐charge limited current (SCLC) measurements, in which the charge carrier is transported through the complete film thickness of several hundred nanometers. Finally, charge carrier mobilities are correlated with the electronic structure of the compounds. We find that in particular the thiophene‐flanked copolymer PDPP[T]2‐EDOT is a very promising candidate for organic photovoltaics, showing an absorption response in the near infrared region with an optical bandgap of 1.15 eV and a very high bulk hole mobility of 2.9 × 10?4 cm2 V?1 s?1 as measured by SCLC. This value is two orders of magnitudes higher than SCLC mobilities reported for other polydiketopyrrolopyrroles and is in the range of the well‐known hole transporting polymer poly(3‐hexylthiophene). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 639–648 相似文献