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41.
In high-voltage applications, large-array n-channel lateral DMOS (LA-nLDMOS) is usually required to provide high driving capability. However, without following the foundry-suggested electrostatic discharge (ESD) design guidelines in order to reduce total layout area, LA-nLDMOS is easily damaged once the parasitic bipolar junction transistor is triggered under ESD stresses. Accordingly, the bipolar triggering of LA-nLDMOS usually limits the ESD robustness of LA-nLDMOS, particularly in the open-drain structure. In this letter, a new layout arrangement for LA-nLDMOS has been proposed to suppress the bipolar triggering under ESD stresses. Measurement results in a 0.5- ${rm mu}hbox{m}$ 16-V bipolar CMOS DMOS process have confirmed that the new proposed layout arrangement can successfully increase the human-body-model ESD level of the LA-nLDMOS with effective width of 3000 ${rm mu}hbox{m}$ from the original 0.75 kV up to 2.75 kV.   相似文献   
42.
CDM ESD event has become the main ESD reliability concern for integrated-circuits products using nanoscale CMOS technology. A novel CDM ESD protection design, using self-biased current trigger (SBCT) and source pumping, has been proposed and successfully verified in 0.13-μm CMOS technology to achieve 1-kV CDM ESD robustness.  相似文献   
43.
MOS-triggered silicon-controlled rectifier (SCR) devices have been reported to achieve efficient on-chip electrostatic discharge (ESD) protection in deep-submicrometer CMOS technology. The channel length of the embedded MOS transistor in the MOS-triggered SCR device dominates the trigger mechanism and current distribution to govern the trigger voltage, holding voltage, on resistance, second breakdown current, and ESD robustness of the MOS-triggered SCR device. The embedded MOS transistor in the MOS-triggered SCR device should be optimized to achieve the most efficient ESD protection in advanced CMOS technology. In addition, the layout style of the embedded MOS transistor can be adjusted to improve the MOS-triggered SCR device for ESD protection.  相似文献   
44.
We are presenting a new approach of identifying sources of variability within a manufacturing process by NIR measurements of samples of intermediate material after each consecutive unit operation (interprocess NIR sampling technique). In addition, we summarize the development of a multivariate statistical process control (MSPC) model for the production of enteric-coated pellet product of the proton-pump inhibitor class. By developing provisional NIR calibration models, the identification of critical process points yields comparable results to the established MSPC modeling procedure. Both approaches are shown to lead to the same conclusion, identifying parameters of extrusion/spheronization and characteristics of lactose that have the greatest influence on the end-product’s enteric coating performance. The proposed approach enables quicker and easier identification of variability sources during manufacturing process, especially in cases when historical process data is not straightforwardly available. In the presented case the changes of lactose characteristics are influencing the performance of the extrusion/spheronization process step. The pellet cores produced by using one (considered as less suitable) lactose source were on average larger and more fragile, leading to consequent breakage of the cores during subsequent fluid bed operations. These results were confirmed by additional experimental analyses illuminating the underlying mechanism of fracture of oblong pellets during the pellet coating process leading to compromised film coating.  相似文献   
45.
A wide set of parameters of concrete containing 10% of ground granulated blast furnace slag as Portland cement replacement involving basic material characteristics, mechanical and fracture-mechanical properties, durability characteristics, hydric and thermal properties and chloride binding characteristics is determined and compared with the parameters of reference Portland cement concrete with otherwise the same composition. The experimental results show that the replacement of Portland cement by even such a low amount of ground granulated blast furnace slag as environmental more friendly and still valuable alternative binder either affects positively or at least does not worsen in a significant way the substantial properties of hardened concrete mix. The mechanical and fracture-mechanical properties are found to be very similar as compared to the reference mix, the liquid water transport parameters of the mix containing slag are significantly better, the basic durability characteristics such as the frost resistance and corrosion resistance similar and very good, the resistance against de-icing salts slightly worse. These findings may be significant for the future use of slag in the countries where its available amount is decreasing and its more efficient use as a binder than it was common to date can appear necessary.  相似文献   
46.
The distance between active region and the seal-ring location has been investigated in a 0.25-μm CMOS process. From the experimental results, this distance can be shrunk to only 5 μm without increasing leakage current and decreasing ESD robustness of the ESD protection devices after reliability tests of High-Accelerated Stress Test (HAST) and Temperature Cycling Test (TCT).  相似文献   
47.
The holding voltage of the high-voltage devices in snapback breakdown condition has been found to be much smaller than the power supply voltage. Such characteristics will cause the LCD driver ICs to be susceptible to the latchup-like danger in the practical system applications, especially while these devices are used in the power-rail ESD clamp circuit. A new latchup-free design on the power-rail ESD clamp circuit with stacked-field-oxide structure is proposed and successfully verified in a 0.25-/spl mu/m 40-V CMOS process to achieve the desired ESD level. The total holding voltage of the stacked-field-oxide structure in snapback breakdown condition can be larger than the power supply voltage. Therefore, latchup or latchup-like issues can be avoided by stacked-field-oxide structures for the IC applications with power supply of 40 V.  相似文献   
48.
Critical considerations in engineering biomaterials for rotator cuff repair include bone‐tendon‐like mechanical properties to support physiological loading and biophysicochemical attributes that stabilize the repair site over the long‐term. In this study, UV‐crosslinkable polyurethane based on quadrol (Q), hexamethylene diisocyante (H), and methacrylic anhydride (M; QHM polymers), which are free of solvent, catalyst, and photoinitiator, is developed. Mechanical characterization studies demonstrate that QHM polymers possesses phototunable bone‐ and tendon‐like tensile and compressive properties (12–74 MPa tensile strength, 0.6–2.7 GPa tensile modulus, 58–121 MPa compressive strength, and 1.5–3.0 GPa compressive modulus), including the capability to withstand 10 000 cycles of physiological tensile loading and reduce stress concentrations via stiffness gradients. Biophysicochemical studies demonstrate that QHM polymers have clinically favorable attributes vital to rotator cuff repair stability, including slow degradation profiles (5–30% mass loss after 8 weeks) with little‐to‐no cytotoxicity in vitro, exceptional suture retention ex vivo (2.79–3.56‐fold less suture migration relative to a clinically available graft), and competent tensile properties (similar ultimate load but higher normalized tensile stiffness relative to a clinically available graft) as well as good biocompatibility for augmenting rat supraspinatus tendon repair in vivo. This work demonstrates functionally graded, bone‐tendon‐like biomaterials for interfacial tissue engineering.  相似文献   
49.
It is apparent that automated inspection for manufacturing is on the threshold of broad industrial utilization. One key problem in manufacturing applications of automated inspection is how to find fast and efficient methods using economical computers that industry can afford. Moreover, most mechanical designers set only overall tolerances for part geometric features. In computer vision inspection, as well as in the use of other automated inspection devices and coordinate measuring machines (CMM) the errors of representing each geometric features should be identified separately. The proposed statistical inference method provides a scientific basis for setting inspection tolerances in original geometric space which are compatible with engineering specifications.

The results of this presentation should supply industrial practitioners with an accurate and fast approach for on-line part profile inspection.  相似文献   

50.
Übersicht Es wird die wirtschaftlichste Form des Ringkern bauelementes gesucht und man denkt dabei an kleinste Materialkosten. Die Aufgabe ist nicht einfach wegen der komplizierten Geometrie der Wicklung; im Prinzip bedient sich der Autor der gleichen Methode, mit welcher er schon in früheren Arbeiten die wirtschaftlich optimale Gestalt von gewöhnlichen Kleintransformatoren bestimmt hat.
Contents The most economical shape of toriodal core components are investigated under the condition of minimum cost of material. Due to the rather complicated geometry of the coil the problem is quite difficult to solve. In principle the same method is applied which was used by the autor in his former works on economically optimal shapes of ordinary small transformers.
  相似文献   
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