【正文】 (mV)/1mV] Decibels relative to one microvolt across same resistance. DC Acronym for Direct Current. detailed physical model A device model wherein its internal detail is described as closely as possible. There is usually a close correlation with the physical construction of the device. device A ponent or part. DFM Acronym for Design For Manufacturability. DFT Acronym for Design For Test. DIE Acronym for Die Information Exchange. dielectric Dielectric materials are poor conductors of electricity, and are insulators that are used to provide separation between conductors. Dielectric materials can be made to hold an electrostatic charge while dissipating minimal energy in the form of heat. Glass, porcelain, mica, rubber, plastics dry air, vacuums and some liquids and gases are dielectric. For example: air, FR4, and GETEK. dielectric constant (relative) An inherent property of dielectric materials that determines the amount of electric charge that can be stored. The higher the constant, E, the higher the energy stored in the material’s capacitance. E is usually measured and reported in formulas relative to air (Er). Air then gets an Er, = 1. FR4 often has a low frequency Er = depending on starting materials and processing. In solid dielectrics Er will fall off starting with high frequencies while signal attenuation increases. Er affects transmission line behavior, particularly characteristic impedance (Zo) and propagation delay (td). The changes in td with frequency cause decreased delay leading to dispersion, or spreading distortion, of a time domain pulse that is posed of many frequencies. digital Data varying between two discrete levels. Electronic signals or switches based on discrete, binary electrical levels (ones and zeros) found in such products as touchtone telephones and audio pact disk players. These signals are either ON or OFF, HIGH or LOW, YES or NO. The mathematical description in digital products is simple, since it is either ON or OFF. DIP Acronym for Dual InLine Package. discrete As in discrete ponent. Package containing only a single ponent as opposed to an integrated circuit containing many ponents in a single package. dispersion 1. The scattering of values of a measurement around the mean or median of the . A distribution. dispersion, dielectric A high frequency effect in dielectric materials. At high frequencies the dielectric constant decreases causing an increase in propagation velocity and a dispersion in arrival times of wave frequency ponents. DML Acronym for Device Modeling Language (Cadence) and associated .dml files. documentation Reports such as data sheets, process control, product characterization, process characterization, and models. May be produced by either the supplier or customer to describe or depict the semiconductor process. DOE Acronym for Design Of Experiments. doping The process of adding impurity atoms to intrinsic (pure) silicon or germanium to improve the conductivity of the semiconductor material. DSP Acronym for Digital Signal Processing. DTL Acronym for DiodeTransistor Logic. DUT Acronym for Device Under Test. E Early effect A behavior in narrow base BJT transistors named for Dr. J. Early who explained it. The effect is an increase in b due to base narrowing caused by increasing basecollector bias voltage. EBD Acronym for Electronic Board Description (IBIS) and the associated .ebd files. ECL Acronym for Emitter Coupled Logic. EDA Acronym for Electronic Design Automation. EDA software tools or tool suites may display simulator output for analysis (as in waveform analyzers) or which may analyze the reliability, electromagic interference, metal migration, signal integrity, or thermal characteristics of a design. The tools in this category may work at any level of abstraction — behavioral, registertransferlevel (RTL), gatelevel, or with the physical layout of an IC device or electronic system. EDIF Acronym for Electronic Design Interchange Format. EIA Acronym for Electronic Industries Association. EIAJ Acronym for Electronics Industries Association of Japan. EKV Acronym for EnzKrummenacherVittoz model. ElectroMagic Integrity The technical discipline of designing for ElectroMagic Control (EMC) and low ElectroMagic Interference (EMI), so that one circuit (or equipment) does not interfere with another circuit (or equipment). The design task begins with designing for good Signal and Power Integrity and adds the concerns of coupling and radiation. The noise energy available to the coupling and radiation mechanisms can be suppressed with good Signal and Power Integrity. The next step is good design control over coupling and radiation mechanisms. These additional actions include controlling: shielding。 Internationale Sp233。 board resonances。frequency. This raises the per unit length resistance of the conductor and its losses. This is the reason that a hollow metallic waveguide is used, or even just a dielectric rod, at microwave frequencies to guide signals. SMD Acronym for Surface Mount Device. SMT Acronym for Surface Mount Technology. SParameter model A type of Matrix model where the port properties are characterized by forward and reflected wave scattering coefficients. Measured into transmission line matched loads. Also know as Scatteringparameter model. SPC Acronym for Statistical Process Control. specsmanship The practice of guardbanding specification limits with more, or less, than sufficient margin, while maintaining the perception of a wellperforming part. SPICE model Acronym for Simulation Program with Integrated Circuit Emphasis. An industrystandard analog simulation language, which contains many models for most circuit elements and can handle plex nonlinear circuits. Also refers to a freely distributed simulation tool, w