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71.
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Ming-Dou Ker Chyh-Yih Chang Yi-Shu Chang 《Components and Packaging Technologies, IEEE Transactions on》2004,27(3):445-451
This paper reports a real case of electrostatic discharge (ESD) improvement on a complementary metal oxide semiconductor integrated circuit (IC) product with multiple separated power pins. After ESD stresses, the internal damage have been found to locate at the interface circuit connecting between different circuit blocks with different power supplies. Some ESD designs have been implemented to rescue this IC product to meet the required ESD specification. By adding only an extra ESD clamp N-channel metal oxide semiconductor with a channel width of 10 /spl mu/m between the interface node and the ground line, the human-body-model (HBM) ESD level of this IC product can be improved from the original 0.5 to 3 kV. By connecting the separated vertical sync signal (VSS) power lines through the ESD conduction circuit to a common VSS ESD bus realized by the seal ring, the HBM ESD level of the enhanced version IC product with 12 separated power supplies pairs can be significantly improved from original 1 kV up to > 5 kV, without the noise coupling issue. 相似文献
74.
Haiyan Chen Jizhi Dai Yongzhi Liu 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(5):749-757
The effect of fog and clouds in millimeter communication is discussed, and the attenuation caused by fog and clouds is reviewed. Signal-to-noise ratio (SNR) of image is derived using relating models of fog and clouds attenuation. According to the relation of image quality and its signal-to-noise ratio, the system behavior is forecasted theoretically. It is shown that the signal-to-noise ratio of receiver at certain transmitter power is inverse with radio wave frequency, from about 70dB at 10GHz to 48dB for fog and 49dB for clouds. The image quality of received signal at certain transmitter power is inverse with radio wave frequency, from about 7 grade at 10GHz to 5.27 grade for fog and 5.37 grade for clouds. The above calculated results are consistent with experimental results. 相似文献
75.
Ching-Wen Tang Chi-Yang Chang 《Electronics letters》2002,38(15):801-803
A novel chip-type ceramic balun designed in the 2.4 GHz ISM band frequency is presented. A buried capacitor is included in the balun, so that the length of the coupled transmission lines can be reduced and can be designed very easily. A meander or spiral broadside coupled-line is adopted to realise the proposed LTCC multi-layer balun. The measured performances of phase and amplitude balance for this LTCC-MLC balun show a good match with computer simulation 相似文献
76.
在实验室条件下对用丙烯腈-苯乙烯共聚物在硫酸存在下的水解磺化产物(HSAS)处理的泥浆性能进行了评定。HSAS处理的泥浆有较小的滤失性,较好的耐盐和抗高温性。 相似文献
77.
回热损失对磁斯特林制冷循环制冷率的影响 总被引:7,自引:0,他引:7
从铁磁质的磁化强度一般表示式出发,探讨热阻和回热损失对磁斯特林制冷循环性能的影响,导出最大制冷率及其它性能参数。得到了结果适用于以顺磁质为工质的磁斯特林制冷循环。并指出在理想回热条件下的结论也适用于磁卡诺制冷循环。 相似文献
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79.
报导一种模糊逻辑控制系统的建模与优化方法。以此方法设计的模糊逻辑控制器,用于双波长稳频CO2激光器的控制得到令人满意的结果。 相似文献
80.
Storage performance-metrics and benchmarks 总被引:2,自引:0,他引:2
Chen P.M. Patterson D.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1993,81(8):1151-1165
The metrics and benchmarks used in storage performance evaluation are discussed. The technology trends taking place in storage systems, such as disk and tape evolution, disk arrays, and solid-state disks, are highlighted. The current popular I/O benchmarks are then described, reviewed, and run on three systems: a DECstation 5000/200 running the Sprite Operating System, a SPARCstation 1+ running SunOS, and an HP Series 700 (Model 730) running HP-UX. Two approaches to storage benchmarks-LADDIS and a self-scaling benchmark with predicted performance-are also described 相似文献