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5.1 The electrical properties of gate and field oxides are altered by ionizing radiation. The method for determining the dose delivered by the source irradiation is discussed in Practices E666, E668, E1249, and Guide E1894. The time dependent and dose rate effects of the ionizing radiation can be determined by comparing pre- and post-irradiation voltage shifts, ΔVot and ΔVit. This test method provides a means for evaluation of the ionizing radiation response of MOSFETs and isolation parasitic MOSFETs.5.2 The measured voltage shifts, ΔVot and ΔVit, can provide a measure of the effectiveness of processing variations on the ionizing radiation response.5.3 This technique can be used to monitor the total-dose response of a process technology.1.1 This test method covers the use of the subthreshold charge separation technique for analysis of ionizing radiation degradation of a gate dielectric in a metal-oxide-semiconductor-field-effect transistor (MOSFET) and an isolation dielectric in a parasitic MOSFET.2,3,4 The subthreshold technique is used to separate the ionizing radiation-induced inversion voltage shift, ΔVINV into voltage shifts due to oxide trapped charge, ΔVot and interface traps, ΔV it. This technique uses the pre- and post-irradiation drain to source current versus gate voltage characteristics in the MOSFET subthreshold region.1.2 Procedures are given for measuring the MOSFET subthreshold current-voltage characteristics and for the calculation of results.1.3 The application of this test method requires the MOSFET to have a substrate (body) contact.1.4 Both pre- and post-irradiation MOSFET subthreshold source or drain curves must follow an exponential dependence on gate voltage for a minimum of two decades of current.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1. Scope 1.1 This Standard covers single-phase, ac electrical installations not exceeding 250 V between conductors or 150 V to ground, on boats which may have an on-board source of electrical supply or may be connected to a source of ac electrical sup

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ASTM F676-97(2003) Standard Test Method for Measuring Unsaturated TTL Sink Current (Withdrawn 2009) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

Unsaturated sink current is a special parameter that is closely related to the gain of the output transistor of TTL circuits. This parameter is particularly useful in evaluating neutron degradation in TTL devices because it changes smoothly as the device degrades, and exhibits larger changes at moderate radiation levels than the standard electrical parameters.1.1 This test method covers the measurement of the unsaturated sink current of transistor-transistor logic (TTL) devices under specified conditions.1.2 Units—The values stated in the International System of Units (SI) are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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1 Scope and object This part of IEC 61000 is concerned with the emission of voltage changes, voltage fluctuations and flicker produced by equipment and impressed on the public low-voltage supply system. It specifies the limits of voltage changes produc

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4.1 Conformable Eddy Current Sensors—Conformable, eddy current sensors can be used on both flat and curved surfaces, including fillets, cylindrical surfaces, etc. When used with models for predicting the sensor response and appropriate algorithms, these sensors can measure variations in physical properties, such as electrical conductivity or magnetic permeability, or both, as well as thickness of conductive coatings on any substrate and nonconductive coatings on conductive substrates or on a conducting coating. These property variations can be used to detect and characterize heterogeneous regions within the conductive coatings, for example, regions of locally higher porosity.4.2 Sensors and Sensor Arrays—Depending on the application, either a single-sensing element sensor or a sensor array can be used for coating characterization. A sensor array provides a better capability to map spatial variations in coating thickness or conductivity, or both (reflecting, for example, porosity variations), and provides better throughput for scanning large areas. The size of the sensor footprint and the size and number of sensing elements within an array depend on the application requirements and constraints, and the nonconductive (for example, ceramic) coating thickness.4.3 Coating Thickness Range—The conductive coating thickness range over which a sensor performs best depends on the difference between the electrical conductivity of the substrate and conductive coating and available frequency range. For example, a specific sensor geometry with a specific frequency range for impedance measurements may provide acceptable performance for an MCrAlY coating over a nickel-alloy substrate for a relatively wide range of conductive coating thickness, for example, from 75 to 400 μm (0.003 to 0.016 in.). Yet, for another conductive coating-substrate combination, this range may be 10 to 100 μm (0.0004 to 0.004 in.). The coating characterization performance may also depend on the thickness of a nonconductive topcoat. For any coating system, performance verification on representative coated specimens is critical to establishing the range of optimum performance. For nonconductive coatings, such as ceramic coatings, the thickness measurement range increases with an increase of the spatial wavelength of the sensor (for example, thicker coatings can be measured with larger sensor winding spatial wavelength). For nonconductive coatings, when roughness of the coating may have a significant effect on the thickness measurement, independent measurements of the nonconductive coating roughness, for example, by profilometry, may provide a correction for the roughness effects.4.4 Process-Affected Zone—For some processes, for example, shot peening, the process-affected zone can be represented by an effective layer thickness and conductivity. These values can in turn be used to assess process quality. A strong correlation must be demonstrated between these “effective coating” properties and process quality.4.5 Three-Unknown Algorithm—Use of multiple-frequency impedance measurements and a three-unknown algorithm permits independent determination of three unknowns: (1) thickness of conductive nonmagnetic coatings, (2) conductivity of conductive nonmagnetic coatings, and (3) lift-off that provides a measure of the nonconductive coating thickness.4.6 Accuracy—Depending on the material properties and frequency range, there is an optimal measurement performance range for each coating system. The instrument, its air standardization or reference substrate standardization, or both, and its operation permit the coating thickness to be determined within ±15 % of its true thickness for coating thickness within the optimal range and within ±30 % outside the optimal range. Better performance may be required for some applications.4.7 Databases for Sensor Response—Databases of sensor responses may be used to represent the model response for the sensor. These databases may be based upon physical models or empirical relations. The databases list expected sensor responses (for example, the real and imaginary parts or the magnitude and phase of the complex transimpedance between the sense element and drive winding) over relevant ranges in the properties of interest. Example properties for a coated substrate material are the magnetic permeability or electrical conductivity of the substrate, or both, the electrical conductivity and thickness of the coating, and the lift-off. The ranges of the property values within the databases should span the expected property ranges for the material system to be examined.1.1 This practice covers the use of conformable eddy current sensors for nondestructive characterization of coatings without standardization on coated reference parts. It includes the following: (1) thickness measurement of a conductive coating on a conductive substrate, (2) detection and characterization of local regions of increased porosity of a conductive coating, and (3) measurement of thickness for nonconductive coatings on a conductive substrate or on a conductive coating. This practice includes only nonmagnetic coatings on either magnetic (μ ≠ μ0) or nonmagnetic (μ = μ0) substrates. In addition to discrete coatings on substrates, this practice can also be used to measure the effective thickness of a process-affected zone (for example, shot peened layer for aluminum alloys, alpha case for titanium alloys) and to assess the condition of other layered media such as joints (for example, lap joints and skin panels over structural supports). For specific types of coated parts, the user may need a more specific procedure tailored to a specific application.1.2 Specific uses of conventional eddy current sensors are covered by Practices D7091 and E376 and the following test methods issued by ASTM: B244 and E1004. Guidance for the use of conformable eddy current sensor arrays is provided in Guide E2884.1.3 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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CSA Preface This is the first edition of CAN/CSA-C61000-3-3, Electromagnetic compatibility (EMC) - Part 3-3: Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current

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