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31.
Modeling and measurement of simultaneous switching noise coupling through signal via transition 总被引:1,自引:0,他引:1
Jongbae Park Hyungsoo Kim Youchul Jeong Jingook Kim Jun So Pak Dong Gun Kam Joungho Kim 《Advanced Packaging, IEEE Transactions on》2006,29(3):548-559
The signal via is a heavily utilized interconnection structure in high-density System-on-Package (SoP) substrates and printed circuit boards (PCBs). Vias facilitate complicated routings in these multilayer structures. Significant simultaneous switching noise (SSN) coupling occurs through the signal via transition when the signal via suffers return current interruption caused by reference plane exchange. The coupled SSN decreases noise and timing margins of digital and analog circuits, resulting in reduction of achievable jitter performance, bit error ratio (BER), and system reliability. We introduce a modeling method to estimate SSN coupling based on a balanced transmission line matrix (TLM) method. The proposed modeling method is successfully verified by a series of time-domain and frequency-domain measurements of several via transition structures. First, it is clearly verified that SSN coupling causes considerable clock waveform distortion, increases jitter and noise, and reduces margins in pseudorandom bit sequence (PRBS) eye patterns. We also note that the major frequency spectrum component of the coupled noise is one of the plane pair resonance frequencies in the PCB power/ground pair. Furthermore, we demonstrate that the amount of SSN noise coupling is strongly dependent not only on the position of the signal via, but also on the layer configuration of the multilayer PCB. Finally, we have successfully proposed and confirmed a design methodology to minimize the SSN coupling based on an optimal via positioning approach. 相似文献
32.
Jong-Jin Pak Yong-Soo Jeong Soon-Jae Tae Dong-Sik Kim Yun-Yong Lee 《Metallurgical and Materials Transactions B》2005,36(4):489-493
The equilibrium solubility of titanium and nitrogen in Fe-Ni melts was measured in the presence of pure solid TiN under various
nitrogen pressures in the temperature range of 1843 to 1923 K. The activity coefficients of titanium and nitrogen relative
to a 1 mass pct standard state in liquid iron were calculated from the experimental results for Fe-Ni alloys of nickel contents
up to 30 mass pct. Nickel decreases the activity coefficient of titanium, but it increases the activity coefficient of nitrogen
in an Fe-Ni-Ti-N melt. Therefore, the effect of nickel on the solubility product of TiN is not significant. The first- and
second-order interaction parameters of nickel on titanium (e
Ti
Ni
and r
Ti
Ni
, respectively) were determined to be −0.0115 and 0 at 1873 K, respectively. Similarly, the interaction parameters of nickel
on nitrogen (e
N
Ni
and r
N
Ni
, respectively) were determined to be 0.012 and 0, respectively, at 1873 K. The temperature dependence of these interaction
parameters was also determined. 相似文献
33.
B. C. Pak B. S. Cho B. J. Baek C. S. Kim B. G. Min 《Journal of Mechanical Science and Technology》1993,7(3):223-230
Hydrodynamic comparison of two polymer valves with two mechanical valves is presented. The valves were perfused in a steady
flow system, and comparisons between the valves were made on the transvalvular pressure distribution and drop, opening area,
and leakage volume. Particular emphasis was placed on a slit-type bileaflet polymer valve which was newly designed and fabricated
in our research group. The results showed that the functional characteristics of a slit-type bileaflet polymer valve compared
favorably with that of mechanical valves. This valve may be a viable and inexpensive alternative, especially for short-term
use in TAH or VAD systems. 相似文献
34.
The thermophysical properties of thin platinum and nickel wires are investigated within the temperature range from room temperature
up to near to the melting point. We have measured the coefficient of heat exchange with the ambient media, the absorption
efficiency factor within the visible range, and the time constant of the bolometer cooling down. The data obtained are approximated
by analytical expressions. 相似文献
35.
Pak Chanil An Kwangil Jang Paeksan Kim Jonggun Kim Sok 《Multimedia Tools and Applications》2019,78(9):12027-12042
Multimedia Tools and Applications - This paper introduces new simple and effective improved one-dimension(1D) Logistic map and Sine map made by the output sequences of two same existing 1D chaotic... 相似文献
36.
Soner Sismanoglu Aliye Tugce Gurcan Zuhal Yildirim-Bilmez Burak Gumustas 《International Journal of Applied Ceramic Technology》2021,18(2):312-318
Information on the mechanical properties and repairability of computer-aided design/computer-aided manufacturing (CAD/CAM) blocks is scarce. Five CAD/CAM blocks with similar indications were evaluated, including four resin nanoceramics, one polymer-infiltrated ceramic network (PICN), and one feldspathic ceramic. CAD/CAM blocks were sectioned into 4 mm × 1.2 mm × 13 mm bars for flexural strength (FS), and 4 mm thick blocks were prepared for elastic modulus (EM), nanohardness (NH), and microshear bond strength (µSBS) testing. FS of the CAD/CAM blocks was determined using a three-point bending test, whereas EM and NH values were measured using a nanoindenter. The reparability of the tested block materials was determined by the µSBS test. One-way ANOVA was conducted for FS, EM, NH, and µSBS followed by Tukey's pairwise comparison (α < 0.05). FS ranged from 115 to 207 MPa, EM from 8.21 to 44 GPa, NH from 0.76 to 7.24, and µSBS from 24.9 to 30.6 MPa. The findings of the present study revealed that resin nanoceramic blocks exhibited higher FS values than PICN and feldspathic ceramic, and they have acceptable mechanical properties for the fabrication of single-unit restorations according to the ISO 6872:2008. Furthermore, all CAD/CAM blocks tested can be successfully repaired regarding their recommended repair protocol. 相似文献
37.
Akin Mustafa Günsel Armağan Bilgiçli Ahmet T. Tüzün Burak Arabaci Gulnur Şaki Neslihan Yarasir M. Nilüfer 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(3):609-618
Protection of Metals and Physical Chemistry of Surfaces - Corrosion inhibition effects of water-soluble peripheral substituted cobalt, copper and zinc metallophthalocyanines (CoPc (1), CuPc (2) and... 相似文献
38.
39.
40.
Min Jiang Xin-Hua Wang Jong-Jin Pak 《Metallurgical and Materials Transactions B》2014,45(4):1248-1259
ZrO2 crucible experiments were carried out in the laboratory to study the formation of low-melting-point inclusions in steel, during which aluminum deoxidization and a high-basicity calcium aluminate refining slag (CaO/SiO2: 6 to 8, Al2O3 40 to 45 pct) were used. Four experiments were done with different slag/steel reaction times (30, 60, 90, and 180 minutes). It was found that inclusions were mainly composed of CaO-Al2O3-ZrO2 with very limited SiO2, in spherical morphology and with sizes mainly less than 5 μm. They can be classified into two types according to the ZrO2 content. The first type contained much lower ZrO2, whereas a much higher level of ZrO2 was detected in the other type. An evolution of inclusions with the reaction time was observed and studied. The obtained results indicated that chemical compositions of inclusions were widely scattered in the CaO-Al2O3-ZrO2 phase diagram after 30 min reaction. However, the composition of inclusions became much more uniform and concentrated in low-melting-temperature regions at 60, 90, and 180 minutes, which would be favorable to prevent nozzle clogging and fatigue problems. Compared with the authors’ previous results obtained in MgO crucible experiments, it was found that low-melting-temperature inclusions can be targeted in shorter time in ZrO2 crucible experiments, without any degradation of cleanliness. 相似文献