A

Symbol for ampere.

abstract

To simplify.

ABT

Acronym for Advanced BiCMOS Technology, as in 74ABT245.

ABTE

Acronym for Advanced BiCMOS Technology/Enhanced logic,  as in 74ABTE245.

ABTH

Acronym for Advanced BiCMOS Technology logic with bus-Hold, as in 74ABTH245.

AC

Acronym for Alternating Current.

AC

Acronym for Advanced CMOS logic, as in 74AC245.

accuracy

1.  The extent to which a given measurement, or the average of a set of measurements, agrees with the true value for that measurement. 2.  Agreement between simulation results and lab measurements.

ACL

Acronym for Advanced CMOS Logic, as in 74ACL245.

ACT

Acronym for Advanced CMOS logic with TTL compatible inputs.

AEA

Acronym for American Electronic Association.

AEA

Acronym for American Engineering Association.

AHDL

Acronym for Analog Hardware Description Language.

AMS

Acronym for Analog Mixed-Signal (hardware description language).

analog

Information represented as continuously varying voltage or current rather than in discrete levels as opposed to digital data varying between two discrete levels.

ANOVA

Acronym for Analysis Of Variance

ANSI

Acronym for American National Standards Institute.

AQL

Acronym for Acceptable Quality Level.

ASCII

Acronym for American Standard Code for Information Interchange.

ASIC

Acronym for Application Specific Integrated Circuit.

ASTM

Acronym for American Society for Testing and Materials.

AWE

Acronym for Asymptotic Waveform Evaluation. Model order reduction. Such as reducing a large RC network to a smaller RC network for faster simulation. This modeling method has known frequency limits for accuracy.

behavioral model

Provides data on behavior at the input and output ports of a device. What the device consists of internally remains a black (opaque) box. Usually used when scanning a large design for the first time. At that point speed is desired over detail.
 

behavioral modeling

System-level modeling consisting of a functional specification plus modeling of the timing of an implementation. A behavioral model consists of an HDL description of a device or component, which is expressed at a relatively high level of abstraction (higher than the register-transfer level or gate level). It uses underlying mathematical equations to represent the functional behavior of the component. See also functional modeling.
 

BEM

Acronym for older Boundary Element Method. Method of numerical computational electromagnetics. Dates from before the 1980s. Requires ground plane.

BER

Acronym for Bit Error Rate.

BGA

Acronym for Ball Grid Array.

BiCMOS

Acronym for Bipolar Complementary Metal Oxide Semiconductor.

BIRD

Acronym for Buffer Issue Resolution Document – IBIS Committee.

BJT

Acronym for Bipolar Junction Transistor.

BNC

Acronym for Bayonet Neill Concelman Connector.

BOM

Acronym for Bill Of Materials.

BSIM

Acronym for Berkeley Short-channel IGFET Model.

BTL

Acronym for Backplane Transceiver Logic, as in 74BTL245.

C

1.  Symbol for capacitance. 2.  Abbreviation for degrees Celsius/Centigrade.

CAD

Acronym for Computer Aided Design.

CAE

Acronym for Computer Aided Engineering.

CAM

Acronym for Computer Aided Manufacturing.

CB

Acronym for Complementary Bipolar, as in 74CB245.

CEM

Acronym for Computational Electromagnetics.

characteriza-tion model

Another term for a device’s data sheet. Displays the behavior of various properties over current, frequency, temperature, population spread, etc. Characterize means to describe and depict.

circuit

Interconnection of components to provide an electrical path between two or more components.

CISPR

Acronym for Comité Internationale Spécial des Perturbations Radioelectrotechnique.

CMC

Acronym for Compact Model Council.

CML

Acronym for Current Mode Logic.

CMOS

Acronym for Complimentary Metal Oxide Semiconductor.

CMRR

Acronym for Common Mode Rejection Ratio.

Confidence interval

A statistical range with a specified probability that a given parameter lies within the range.

Confidence level

Example: Suppose an opinion poll predicted that, if the election were held today, the Conservative party would win 60% of the vote. The pollster might attach a 95% confidence level to the interval 60% plus or minus 3%. That is, he thinks it very likely that the Conservative party would get between 57% and 63% of the total vote.

Confidence limit

Either of the two numbers that specify the endpoints of a confidence interval.

correlation

1. How well a set of measurements agrees with a separate set of measurements on the same group of units. One or more attributes may be used. 2. Process of making a quantitative comparison between two sets of data. Also, from the word roots co: together and relation.

correlation metric

A means of quantifying agreement between two sets of data.

COTS

Acronym for Commercial Off-The-Shelf apparatus.

CPD

Acronym for Cumulative Probability Distribution (function).

crosstalk

The amount of signal from one conductor that gets coupled onto an adjacent conductor through the mutual capacitance and inductance between them. The magnitude of the effect is always a fraction of the active, or aggressor, net upon the passive, or victim, net. The amount of coupling depends on the proximity of the nets, the proximity of any ground/power plane, the length of any parallel runs, the risetime of the driving signal and the dielectric medium between them.

current carrier

A current carrier is either a conduction band electron or a conduction band hole.

DARPA

Acronym for Defense Advanced Research Projects Agency.

data sheet

Documentation created after the properties and behavior of a population of devices, from a statistically in-control process, are characterized.

dB

Acronym for decibel. The number of decibels denoting the ratio of the two amounts of power being ten times the logarithm to the base 10 of this ratio. With P1 and P2 designating two amounts of power and n the number of decibels denoting their ratio.(ANSI C63.14 – 1992) N = 10log10 (P1/P2) dB

dBmV/m

Symbol for decibels-micro-Volts per meter. where dBmv = 20 log [Signal (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 component 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 (e_r). Air then gets an e_r, = 1. FR4 often has a low frequency e_r = 4.3 depending on starting materials and processing. In solid dielectrics e_r  will fall off starting with high frequencies while signal attenuation increases. e_r affects transmission line behavior, particularly characteristic impedance (Zo) and propagation delay (t_d).  The changes in t_d with frequency cause decreased delay leading to dispersion, or spreading distortion, of a time domain pulse that is composed 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 touch-tone telephones and audio compact 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 component.  Package containing only a single component as opposed to an integrated circuit containing many components in a single package.

dispersion

1. The scattering of values of a measurement around the mean or median of the measurement.2. 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 components.

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 Diode-Transistor Logic.

DUT

Acronym for Device Under Test.

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 base-collector 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, electromagnetic interference, metal migration, signal integrity, or thermal characteristics of a design. The tools in this category may work at any level of abstraction — behavioral, register-transfer-level (RTL), gate-level, 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 Enz-Krummenacher-Vittoz model.

ElectroMagnetic Integrity

The technical discipline of designing for ElectroMagnetic Control (EMC) and low ElectroMagnetic 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; cabling; leakage; board resonances; enclosure resonances; structural behavior that operates as an antenna.

EM

Acronym for ElectroMagnetic.

EMC

Acronym for ElectroMagnetic Compatibility. The capability of Electrical and Electronic Systems, equipment and devices to operate in their intended electromagnetic environment within a defined margin of safety, and at design levels of performance, without suffering or causing unacceptable degradation as a result of electromagnetic interference (ANSI C63.14 – 1992).

EMI

Acronym Electromagnetic Interference. The electromagnetic disturbances (electronic noise) in an environment that can affect an electronic device, or that which is being produced by an electronic device, or both. EMI analysis tools are used to verify EMC compliance during the design of high-speed PCBs and IC packages. The traditional EMI remedies involve the addition of extra components, metal shields, metal plans, or even redesigning the entire system. Synonym: radio-frequency interference.

EMI/EMC

Acronym for Electromagnetic Interference/Electromagnetic Control.

equation-based model

A model based on equations that describe the behavior of the device, or circuit, modeled. Most importantly, the output as a function of the input.

ESD

Acronym for ElectroStatic Discharge. A transfer of electric charge between bodies of different electrostatic potential in close proximity or through direct contact (ANSI C63.14 – 1992).

ESS

Acronym for Environmental Stress Screening.

eV

Abbreviation for electron-volt.

F

Symbol for Farad, measure of capacitance.

f

Abbreviation for frequency.

FACT

Acronym for Fairchild Advanced Cmos Technology, as in 74FACT245.

FAST

Acronym for Fairchild Advanced Schottky TTL, as in 74F245.

FCT

Acronym for Fast Cmos Technology, as in 74FCT245.

FDTD

Acronym for Finite Difference Time Domain modeling.

FEA

Acronym for Finite Element Analysis.

FEM

Acronym for Finite Element Method. Method of numerical computational electromagnetics. Essentially everybody does some form of this for field solvers, such as T-lines.

FET

Acronym for Field Effect Transistor.

FFT

Acronym for Fast Fourier Transform.

FOM

Acronym for Figure Of Merit.

FPGA

Acronym for field programmable gate array.

functional modeling

Modeling by the use of mathematical functions, algorithms and formulas.

G

Symbol for giga, as in10⁺¹²

GaAs

Acronym for Gallium Arsinide.

GB or Gbit or GBIT

Acronym for GigaBit.

glue logic

Small ICs that level shift and otherwise perform simple functions that enable large blocks of logic (ASICs, microprocessors, memories) to work together. Thus gluing them together.

GND

Acronym for GrouND. A reference connection commonly connected to Earth, whose electric potential is usually equal to zero.

ground bounce

The transient rise or fall in voltage on a ground plane or ground pin from its ideal quiescent value of zero due switching currents on and off through impedance (mostly inductance) in the ground path. A similar effect on the power plane causes power bounce. The result is noise on the signal that can decrease signal to noise ratio in analog circuits or lead to false switching in digital circuits.

GTL

Acronym for Gunning Transceiver Logic, as in 74GTL245.

GTLP

Acronym for Gunning Transceiver Logic Plus, as in 74GTLP245.

guard-banding

The practice of adding safety margin, or extra safety margin, to specification limits or population distributions.

H

Abbreviation for Henry, the unit of inductance.

HALT

Acronym for Highly Accelerated Life Test.

HASS

Acronym for Highly Accelerated Stress Screening.

HC

Acronym for High speed Cmos, as in 74HC245.

HCT

Acronym for High speed Cmos with TTL thresholds, as in 74HCT245.

HDL

Acronym Hardware Description Language. One of several specialized high-level languages used by semiconductor designers to describe the features and functionality of chips and systems prior to handoff to the IC layout process. HDL descriptions are used in both the design implementation and verification flows. Currently, the two standard HDLs in use worldwide are Verilog-HDL and VHDL. Several proprietary HDLs also exist, mainly for describing logic that is targeted for vendor-specific programmable logic devices.

high-speed digital design

The design of digital circuits relative to their analog behavior. Particularly, where the fast switching edge rates used cause transmission line effects to become significant.

hole

A gap left in the covalent bond when a valence electron gains sufficient energy to jump to the conduction band.

HSDD

Acronym for High-Speed Digital Design. HSDD, as used in this book, applies to both active and passive circuit elements.

HSTL

Acronym for High Speed Transceiver Logic.

HTL

Acronym for High Threshold Logic.

HTTL

Acronym for High power Transistor-to-Transistor Logic.

Hz

Symbol for Hertz, as in cycles per second.

I/O

Symbol for Input/Output.

IBIS

Acronym for Input/output Buffer Information Specification.

IBIS model

A data file produced in conformance with the IBIS Specification. The IBIS file, or model, provides necessary data for a simulator to predict the analog behavior of digital circuits.

IBIS quality levels

Four levels of increasing quality as defined in the IBIS quality checklist.

IBIS rise time

Rise time based on the IBIS [Ramp] specification of 20% to 80% of 0 Volts to Vcc switching.

IC

Acronym for Integrated Circuit.

ICEM

Acronym for Integrated Circuits Electromagnetic Model, specification 62014-3 from IEC.

ICM

Acronym for IBIS Interconnect Modeling Information (specification). Connectors, packages, and interconnections.

ideal-generic models

Examples: ideal current source, ideal operational amplifier.

IEC

1. Acronym for International Engineering Consortium 2. Acronym for International Electrotechnical Commission

IEEE

Acronym for Institute of Electrical and Electronics Engineers.

IGBT

Acronym for Insulated Gate Bipolar Transistor.

IGFET

Acronym for Insulated Gate Field Effect Transistor.

impedance

Measured in ohms, it is the total opposition to the flow of current offered by a circuit element. Impedance consists of the vector sum of resistance and reactance. The symbol, or term, for impedance is Z.

in-control (SPC)

A statistical process control (SPC) term that means that only random variation is seen in the process and that there are no special cause reasons for variation.

IP

Acronym for Intellectual Property.

ISO

Acronym for International Standards Organization.

JEDEC

Acronym for Joint Electron Device Engineering Council.

JFET

Acronym for Junction Field Effect Transistor.

junction

Contact or connection between two or more wires or cables. The area where the p-type material and n-type material meet in a semiconductor.

K

Symbol for kilo, as in 1000.

Keyword

Special words, as used in the IBIS Specification, that are reserved and set off by square brackets. Example: [File Name]. These terms are recognized and parsed by simulation software programs.

L

Symbol for inductance.

LSL

Acronym for Lower Spec Limit

LSTTL

Acronym for Low power Schottky Transistor-to-Transistor Logic, as in 74LSTTL245.

LVC

Acronym for Low Voltage CMOS, as in 74LVC245.

LVDS

Acronym for Low Voltage Differential Signaling, as in 74LVDS245.

LVT

Acronym for Low Voltage Transceiver, as in 74LVT245.

LVTTL

Acronym for Low Voltage Transistor-to-Transistor Logic, as in 74LVTTL245.

M

Symbol for million, 1,000,000.

macromodel

A model composed of several sub-elements. Used early on in top-down design approaches or to simplify standard blocks of circuitry. For example an OpAmp macromodel. Still possesses an ability to be decomposed into smaller, simpler blocks of circuitry.

majority carrier

The conduction band electrons in an n-type material and the valence band holes in a p-type material. Produced by pentavalent impurities in n-type material and trivalent impurities in p-type material.

MAST

Not an acronym, but the abbreviation of MAST AHDL (language), a registered trademark of Analogy, Inc.

matched

Condition that occurs when the output impedance of a source is equal to the input impedance of a load so that maximum power is transferred between the two.

Matrix model

A black-box N by N model in the form of a square matrix where the behavior inside the black box can be characterized by measurements at its input and output ports.

maximum

The usual maximum of a property of a population of devices. Usually defined to be three sigma standard deviations greater than the mean.

mean (and typical)

The average of a property of a population of devices.

micron

A unit of measure equivalent to one-millionth of a meter, synonymous with micrometer. 1 mil = 1 thousandth of an inch = 25.4 microns.

minimum

The usual minimum of a property of a population of devices. Usually defined to be three sigma standard deviations less than the mean.

minority carrier

The conduction band holes in n-type material and valence band electrons in p-type material. Most minority carriers are produced by temperature rather than by doping with impurities.

model

A mathematical prediction of the behavior of a physical system. Also, a functional representation of a device or system. This representation contains the basic structure and characteristics of a design object, which is used to perform design verification. During the development of an electronic system, models are exercised along with signals entering from the outside environment to simulate the behavior of the system in software and ensure that it will operate properly before being manufactured in hardware.

modeling

The process of using models for analysis and simulation.

MoM

Acronym for Method of Moments method of numerical computational electromagnetics. Dates from at least the 1980s. Does not require ground plane.

MOS

Acronym for Metal Oxide Semiconductor.

MOSFET

Acronym for Metal Oxide Semiconductor Field Effect Transistor.

MTBF

Acronym for Mean Time Between Failures.

MTTF

Acronym for Mean Time To Failure.

MTTR

Acronym for Mean Time To Repair.

n-type semiconductor

A semiconductor compound formed by doping an intrinsic semiconductor with a pentavalent element. An n-type material contains an excess of conduction band electrons.

NA

1. Acronym for Not Applicable. 2. Acronym for Not Available.

NASA

Acronym for National Aeronautics and Space Administration.

NC

Acronym for Not Connected.

NDA

Acronym for Non Disclosure Agreement.

net, or network or topology

Combination of interconnected components, circuits or systems.

NIST

Acronym for National Institute for Standards and Technology.

NMOS

Acronym for N-channel Metal Oxide Semiconductor.

Normal distribution

Population distribution. Synonymous with Gaussian distribution. Called normal because its shape is the most common normally seen in nature.

npn

A bipolar junction transistor in which a p-type base element is sandwiched between an n-type emitter and an n-type collector.

p

Symbol for pico, as in 10^-12

parameter

A variable. A means by which an application or user can customize the behavior or characteristics of a model instance when it is created. A parameter is set to a constant value during design entry.

parameterize

A variable that is assigned a specific value or is otherwise made into a physical thing, as in a resistor.

parasitic extraction

Software tools that translate IC and PCB layout data into networks of electrical circuit elements (transistors, resistors and capacitors) and parasitic elements (interconnect capacitance and resistance).

PCB

Acronym Printed Circuit Board. An electronic interconnect product, which is the foundation of most electronic systems. PCBs are used to mount and interconnect chips, capacitors, resistors, and other discrete components required in a piece of electronic equipment. The base material of a PCB is called a dielectric and is generally made of rigid fiberglass, rigid paper, or flexible thin plastic laminates. Those dielectric substrates are then coated with copper and may be fabricated into rigid single- or double-sided, multilayer, or flexible circuits. Also referred to as printed wiring board.

PCI

Acronym for Peripheral Component Interconnect bus, as in reflected wave switching.

PD

Acronym for Probability Distribution (function).

PDS

Acronym for Power Distribution System.

PECL

Acronym for Positive/pseudo Emitter Coupled Logic.

PEEC

Acronym for Partial Element Equivalent Circuit.

physical model

See detailed physical model.

PI

Acronym for Power Integrity.

PKG

Acronym for IBIS Package file denoted .pkg.

PMOS

Acronym for P-type Metal Oxide Semiconductor.

pnp transistor

A bipolar junction transistor with an n-type base and p-type emitter and collector.

Power Integrity

The technical discipline of maintaining clean power distribution in electronic equipment. One where the power distribution system does not transmit noise, and voltages do not sag, bounce or droop under the demands for power.

PPM or ppm

Acronym for parts-per-million.

PRBS

Acronym for Pseudo-Random Bit Sequence.

precision

The extent to which a given set of measurements are repeatable.

probabilistic

Relating to, or governed by, probability. The behavior of a probabilistic system cannot be predicted exactly but the probability of certain behaviors is known. Such systems may be simulated using pseudo-random numbers.

process characterization

Documentation that describes and depicts a process.

process model

Model that applies to an entire process from which more than one device may be manufactured.

product characterization

Documentation that describes and depicts a product.

PWB

Acronym for Printed Wiring Board. See PCB.

PWR

Abbreviation for PoWeR. The rate of generating, transferring or using energy.

Q

Abbreviation for Quality factor of a resonant circuit.

QA

Acronym for Quality Assurance.

QC

Acronym for Quality Control.

quality

The measure of a device’s, or population of devices’, fitness for use.

R

Symbol for resistance.

RASSP

Acronym for Rapid Prototyping of Application Specific Signal Processors (DARPA project).

reflection coefficient, r

The fraction of a signal that gets reflected in a distributed circuit.

RF

Acronym for Radio Frequency.

RFIC

Acronym for RF Integrated Circuit.

rise and fall time

The time for a signal to rise, or fall, from a defined percentage of output swing to a second defined percentage of output swing.

RMS

Acronym for Root Mean Square.

ROI

Acronym for Return On Investment.

RTL

Acronym for Resistor Transistor Logic.

RTL

Acronym for Register Transfer Level. A type of HDL description in which a circuit is modeled by specifying the data flowing between a set of registers, which are elements of a design that transition between states based on an event (a high or low edge) occurring on a clock signal. The register-transfer level of abstraction is above the gate level and below the behavioral level.

SABER

SABER is not an acronym. It is a registered trademark of Analogy, Inc., for their SABER analog simulator.

safety margin

An extra margin of tolerance on a spec limit thus providing an extra margin of safety.

saturation

Condition in which a further increase in one variable produces no further increase in the resultant effect. In a bipolar junction transistor, the condition when the emitter to collector voltage is less than the emitter to base voltage. This condition puts forward bias on the base to collector junction.

Scattering-parameter model

See S-Parameter model.

schematic diagram

Illustration of an electrical or electronic circuit with the components represented by their symbols and wire connections represented by connecting lines.

semi

Abbreviation for semiconductor.

semiconductor

An element that is neither a good conductor nor a good insulator, but rather lies somewhere between the two. Characterized by a valence shell containing four electrons. Silicon, germanium and carbon are the semiconductors most frequently used in electronics.

SERDES

Acronym for Serializer/ De-serializer. High-speed I/O for Backplane Ethernet, PCI E & XAUI

Si

Abbreviation for Silicon.

SI

Acronym for Signal Integrity.

SiGe

Acronym for Silicon-Germanium.

sigma, s

A standard deviation in a population distribution. A statistic used as a measure of the dispersion or variation in a distribution, equal to the square root of the arithmetic mean of the squares of the deviations from the arithmetic mean.

Signal Integrity

The technical discipline of maintaining the waveform integrity of a signal so that the digital logic can work properly. Actions include eliminating reflections, crosstalk, and noise on the signal. The 1’s and 0’s must be kept clean enough so that they are still recognized as 1’s and 0’s.

simulation

The process of verifying an electronic design using EDA software, which reads in models and input/output vectors, exercises the device under test. The software records the resulting electrical behavior and timing information for the purpose of identifying and debugging any incorrect or unexpected behavior.

skin effect

A physical effect on metallic conductors where, as frequency becomes high enough, electric fields cannot penetrate into the conductor. All current then gets conducted on the outer surface (i.e., skin) of the conductor. The thickness of the skin varies as 1/Öfrequency. 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.

S-Parameter 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 Scattering-parameter model.

SPC

Acronym for Statistical Process Control.

specsmanship

The practice of guard-banding specification limits with more, or less, than sufficient margin, while maintaining the perception of a well-performing part.

SPICE model

Acronym for Simulation Program with Integrated Circuit Emphasis. An industry-standard analog simulation language, which contains many models for most circuit elements and can handle complex nonlinear circuits. Also refers to a freely distributed simulation tool, which simulates circuitry described in the SPICE language. By long usage has become synonymous with SPICE model.

SSTL

Acronym for Stub Series Terminated Logic, as in 74SSTL245.

STTL

Acronym for Schottky Transistor-to-Transistor Logic, as in 74STTL245.

SWR

Acronym for Standing Wave Ratio.

system

A group of objects operating together.

TCAD

Acronym for Technology Computer Aided Design

TDR

Acronym for Time Domain Reflectometry.

TEM

Acronym for Transverse ElectroMagnetic wave.

TLM

Acronym for Transmission Line Modeling.

transmission line

Any circuit connection where time delay of a signal propagating down it is large enough so that signal at the receiving end does not instantaneously follow the signal at the sending end. Transmission lines are characterized by inherent impedance, Zo, per unit length that is determined by structure geometry, dielectric and conductor properties. Not all of the signal can be transferred into the load if the input impedance at the receiving end does not match the Zo of the transmission line. A reflection of signal (positive or negative) will be set up to maintain conservation of energy. In a zero time delay circuit this means that the signal level at the sending end would instantaneously adjust to a level consistent with the load. This tracking of send-receive can get out of step if the round trip time delay is greater than the rise time of the signal. Then, the conditions at the sending end, current sent = (generator voltage)/(generator impedance + transmission line Zo) may not match conditions at the receiving end, current accepted =  (generator voltage)/(transmission line Zo + receiving end input impedance). If so, signal reflections will be set up until signal power gets absorbed into the transmit-receive ends and/or dissipated in the transmission line structure.

TTL

Acronym for Transistor-Transistor Logic.

UL

Acronym for Underwriters Laboratory.

USL

Acronym for Upper Spec Limit

V

Symbol for volt.

validation

To give official confirmation or approval. Applied to models, it means verifying that the model correlates with the standard for the model and will run in simulators available for the purpose. Correlation with the standard for the model implies there is one and that the model follows the correct syntax, format, and contains the required data elements. For IBIS it’s possible to also include an eyeball reality check of things like clamp and pullup curves

VBIC

Acronym for Vertical Bipolar Inter-Company.

verification

Applied to models, it means confirmation that simulation predictions of device and circuit behavior correlate with lab measurements. For IBIS it’s possible to correlate the IBIS simulation with a SPICE simulation if the SPICE simulation was verified by measurements.

Verilog

A hardware description language. An industry-accepted standard language used by electronic designers to describe and design their chips and systems prior to fabrication.

Verilog-AMS

Acronym for Verilog Analog Mixed-Signal (hardware description language) extension to Verilog.

VHDL

Acronym for Very-high-speed-integrated-circuit Hardware Description Language. An IEEE-standard hardware description language originally developed by the U.S. Department of Defense as a common means of documenting electronic systems. Specified in the IEEE 1076 standard and used by electronic designers to describe and simulate their chips and systems prior to fabrication, an alternative language to Verilog. Also, referred to as VHSIC.

VHSIC

See VHDL.

VLSI

Acronym for Very Large Scale Integration.

VNA

Acronym for Vector Noise Analyzer.

VRM

Acronym for Voltage Regulator Module.

VSWR

Acronym for Voltage Standing Wave Ratio.

W

Symbol for watts.

Xtalk

Acronym for crosstalk.

y-parameter model

A type of matrix model where the port properties are characterized by input, output, forward and reverse admittances. Measured into AC short circuits. Also known as admittance parameter model.

z-parameter model

A type of matrix model where the port properties are characterized by input, output, forward and reverse impedances. Measured into AC open circuits. Also known as impedance parameter model.