See "mega (as a prefix to units of semiconductor storage capacity)".
See "mode control".
The sequence of operations that corresponds to one memory cycle, input/output (I/O) cycle, or equivalent internal operation in a central processing unit (CPU). (Ref. IEC 824.)
NOTE An instruction may require one or more machine cycles for its execution. A machine cycle usually contains more than one clock cycle.
A characterized fixed layout and interconnection of primitives that implement an electrical function.
NOTE Characterization may be done either by measurement of fabricated devices or by computer simulation or by both. Characterization may include the following aspects: physical dimensions, logic functionality, testability, layout-rule compliance, ac and dc electrical performance, and reliability.
The physical cell area contained within a polygon (often a rectangle) that circumscribes the cell. (See also "unit gate size".)
An interconnection of primitives and/or macrocells that implements an electrical function but has no predetermined physical layout.
The part of internal storage into which instructions and other data must be loaded for subsequent execution or processing. (Ref. ANSI X3.172.)
The main terminal intended by the thyristor manufacturer to conduct the control current in addition to the principal current.
NOTE Some bidirectional triode thyristors are completely symmetrical, e.g., SBS thyristors. For these, the choice for the manufacturer is arbitrary, and the user can return the control circuit to whichever main terminal will provide the required polarity of gate current.
The other main terminal after main terminal 1 has been designated by the thyristor manufacturer.
The two terminals through which the principal current flows.
The type of carrier constituting more than half of the total charge-carrier concentration.
The maximum cumulative time after bake that components may be exposed to ambient conditions prior to shipment to the end user.
All areas and operations where products or services are processed, stored, or handled.
Acceptance testing of a change to a surface finish manufacturing process already accepted by a technology acceptance (q.v.).
A patterned screen of any of several materials and types used in shielding selected areas of a semiconductor, photosensitive layer, or substrate from radiation during processing, so that the unshielded areas can be further processed to reproduce the chosen pattern.
NOTE The type of mask can be designated either by type (e.g., oxide mask or metal mask) or by function (e.g., diffusion mask or vapor-deposition mask).
A write transfer in which the transfer of new data from the serial register into the memory array is controlled by a write mask that is supplied on the DG(n) terminals. This mask allows the selective writing of new data into one or more of the data bit planes of the storage array corresponding to the data bits of the parallel array. In a normal implementation, a high M value enables the writing of new data while a low M inhibits the writing and leaves the existing data unchanged. A new mask value must be supplied for each masked write cycle.
An indicator used in conjunction with other symbols to create a new pin name to signify that the pin function is either mask- or mode-related.
A fixed-program read-only memory in which the data content of each cell is determined during manufacture by the use of a mask. (Ref. IEC 748‑2.)
Nonvolatile auxiliary storage of large capacity used for storage of data to which infrequent reference need be made.
An unmetalized wafer containing arrays of circuit elements as determined by subsystem requirements.
NOTE These circuit elements can be interconnected in a variety of ways to achieve different functions.
An output signal that, when true, indicates that there has been a match (logic compare equal) between data stored in the memory and data presented on a set of input pins as defined in the individual device standard.
A pair of microwave diodes identical in outline dimensions and with matched electrical characteristics as described in EIA-370.
NOTE The two diodes may both be forward polarity, or one forward and one reverse polarity, or both reverse polarity.
The one or more substances of which something is made; e.g., an alloy is a material, which in turn is made up of a number of substances.
Product that exhibits significant anomalous characteristics that may cause a higher-than-normal level of failure anywhere in the user's application or user's manufacturing line.
NOTE 1 In this definition, "product" includes the electronic component, the first level packing (e.g., tray, tube, and tape and reel), the shipping container, labeling, and paperwork.
NOTE 2 These significant anomalous characteristics can include initial quality defects, time-dependent reliability defects, defects that affect next level of manufacturing, defects in product delivery process (such as labeling or shipping media), and defects in business process (such as shipping information). The characteristics may or may not be part of an existing product or process monitor, test, or inspection activity.
NOTE 3 Maverick product may come from known noncompliant product, from compliant product that differs significantly from "typical" product (but is still within specification limits), or from "normal" product due to some previously unknown or unmonitored cause.
(1) The higher-magnitude limit of a range of some quantity.
(2) For logic levels and temperatures only, the more positive (less negative) limit.
The maximum slope of the ID-VGS curve in the linear region.
NOTE 1 The gate voltage is varied in increments no greater than 20 mV from below the turn-on voltage to a value great enough to ensure that the maximum slope point has been reached.
NOTE 2 The slope is calculated using a three-point linear least-squares best-fit algorithm as defined in ASTM F617‑86.
A feature of size that contains the maximum amount of material, e.g., maximum shaft diameter or minimum hole diameter.
The gate charge necessary to reach a specified maximum gate-source voltage.
NOTE The magnitudes of gate charge and voltage are referred to the coordinate origin (0,0).
See "absolute maximum rated junction temperature".
The maximum supply voltage at which a device is specified to operate in compliance with the applicable device specification.
NOTE 1 "Maximum" refers to the magnitude of supply voltage and can be either positive or negative.
NOTE 2 The maximum operating voltage is not the absolute maximum-rated voltage, i.e., the voltage beyond which permanent damage is likely.
The peak positive or negative output current swing, referred to zero, that can be obtained without waveform clipping.
The peak positive or negative output voltage swing, referred to zero, that can be obtained without waveform clipping.
The maximum peak-to-peak output voltage that can be obtained without waveform clipping when the quiescent dc output voltage is set at a specified reference level.
A rating that establishes either a limiting capability or a limiting condition beyond which damage to the device may occur. (Ref. IEC 747‑1.)
NOTE 1 A limiting condition may be either a maximum or a minimum.
NOTE 2 IEC 747‑1 refers to such a limiting condition as a "rating (limiting value)".
The upper limit of an application use condition.
See "maximum operating (supply) voltage".
See "moisture barrier bag".
See "multiple-bit upset".
See "must connect high".
See "must connect low".
See "multichip module".
See "microcontroller" and "multiple-cell upset".
The sum of the population values divided by the number of values in the population. A measure of location (central tendency) equal to the center of gravity of the population.
The mean value of the individual average junction temperatures, TJ(AV), of a sample of semiconductor devices when the devices are operated under specified life-test conditions.
The mean value of the instantaneous power loss in a particular period of the cycle, averaged over the full cycle.
NOTE The term "power dissipation" has been used in the past as a true synonym for "power loss". This is no longer recommended. The term "loss" should refer to the electrical loss (IR drop) at the place of its origin, and the term "dissipation" should refer to the heat that is dissipated from the surface of the device into the environment. Different terms must be provided for the two quantities because, due to internal storage of heat, the two differ with time.
As an exception, "mean power dissipation" may still be used as a synonym for "mean power loss", but only when appropriate, i.e., if the differences with time have no influence on the mean values of the two. This is the case for mean values that are averaged over a cycle. In the latter case, the subscript "(AV)" is usually omitted from the letter symbols.
The leak rate of a given package as measured under specified conditions and employing a specified test medium. Measured leak rate shall be expressed in units of atmosphere cubic centimeters per second (atm-cm3/s).
The current applied to the device under test during the measurement of the temperature sensitive parameter.
Time from removal of heating conditions to the start of the measurement sample window.
A mark, chamfer, notch, tab, flat, or similar feature that allows mechanical, optical, electrical, or pneumatic sensing during mechanized handling. It may or may not identify the number-one terminal position.
The middle value in a group of measurements when arranged from lowest to highest. When the number of measurements is an even number, the average of the two middle values is used as the median. A measure of location.
A multiplier equal to 1 048 576 (220 or K2, where K = 1024).
NOTE 1 Contrast with the SI prefix mega (M) equal to 106, as in a 1‑Mb/s data transfer rate, which is equal to 1 000 000 bits per second.
NOTE 2 The definitions of kilo, giga, and mega based on powers of two are included only to reflect common usage. IEEE/ASTM SI 10‑1997 states "This practice frequently leads to confusion and is deprecated." Further confusion results from the popular use of a "megabyte" consisting of 1 024 000 bytes to define the capacity of the familiar "1.44‑MB" diskette. An alternative system is found in Amendment 2 to IEC 60027‑2: Letter symbols to be used in electrical technology - Part 2:
Prefixes for binary multipliers
Factor Name Symbol Origin Derivation
210 kibi Ki kilo + binary: (210)1 = 1 024 kilo: (103)1
220 mebi Mi mega + binary: (210)2 = 1 048 576 mega: (103)2
230 gibi Gi giga + binary: (210)3 = 1 073 741 824 giga: (103)3
240 tebi Ti tera + binary: (210)4 = 1 099 511 627 776 tera: (103)4
IEC suggests that, in English, the first syllable of the name of the binary-multiplier prefix should be pronounced in the same way as the first syllable of the name of the corresponding SI prefix and that the second syllable should be pronounced as "bee".
The smallest subdivision of a memory into which a unit of data has been or can be entered, in which it is or can be stored, and from which it can be retrieved. (Ref. IEC 748‑2.)
An integrated circuit consisting of memory cells and usually including associated circuits such as those for signal amplification and address selection. (Ref. IEC 748‑2.)
A subdivision of a memory, including one or several memory cells, that is the smallest part of the memory that can be addressed.
NOTE The content of a memory location is usually called a bit, a byte, or a word, as appropriate.
The arrangement of memory cells, either by geometrical arrangement in rows and columns or by organization of the data to be stored. (Ref. IEEE Std 641.)
See "metal-semiconductor field-effect transistor".
See "manufacturer's exposure time".
A technology for producing circuits and circuit elements having the form of a semiconductor-insulator-metal layered structure.
NOTE Field-effect transistors, capacitors, varactors, nonlinear resistors, variable-threshold diodes, and similar circuit elements can be produced with this technology.
A thin-film metallic conductor or network of such conductors used to interconnect microcircuit elements.
The metallization on the bottom surface of a chip that permits bonding it to a mounting substrate.
A metallization pattern in which the conductive network is fabricated in more than one plane and separated, except at desired contact points, by thin dielectric films.
A subcategory of metal-insulator-semiconductor (MIS) technology in which the insulation employed is a nitride-oxide layer.
An insulated-gate field-effect transistor in which the insulating layer between each gate electrode and the channel is oxide material and the gate is metal or another highly conductive material. (Ref. IEC 747‑8.)
A subcategory of metal-insulator-semiconductor (MIS) technology in which the insulator employed is an oxide of the semiconductor substrate material.
NOTE The term MOS is often misused to include other categories of insulated-gate technology such as MNOS (metal-nitride-oxide-semiconductor) and SIS (silicon-gate-insulator semiconductor).
A varistor having a sintered metal-oxide element.
NOTE The device exhibits a symmetrical voltage-current characteristic.
A field-effect transistor in which a metal-semiconductor rectifying contact is used for the gate electrode.
NOTE 1 Typically the structure is fabricated in gallium arsenide and the term GaAs MESFET may be used.
NOTE 2 Both depletion-type and enhancement-type devices have been manufactured. The acronyms are D-MESFET and E-MESFET, respectively.
(1) A standard of measurement.
(2) A quantitative measure of an activity, results, and/or reaction.
(3) Of, relating to, or using the metric system.
Merriam-Webster's Collegiate Dict.
A code assigned by JEDEC that identifies manufacturers. JEP-106 is the publication containing the codes.
A microelectronic device that has a high circuit-element and/or component density and that is considered to be a single unit. (Ref. IEC 748-1.) (See also "integrated circuit".)
Synonym for "integrated circuit, analog".
Synonym for "integrated circuit, binary".
Synonym for "integrated circuit, digital".
Synonym for "integrated circuit, film".
Synonym for "integrated circuit, hybrid".
Synonym for "integrated circuit, interface".
Synonym for "integrated circuit, linear".
Synonym for "integrated circuit, digital".
An assembly of microcircuits, or an assembly of microcircuits and discrete parts, designed to perform one or more electronic circuit functions and so constructed that, for the purpose of specification, testing, commerce, and maintenance, it is considered to be indivisible.
Synonym for "integrated circuit, multichip".
A computer system whose central processing unit (CPU) is a microprocessor.
NOTE A basic microcomputer includes a microprocessor, memory, and input/output ports; these may or may not be on the same chip. See also "microcontroller".
A microcomputer on a single chip.
NOTE A microcontroller is generally dedicated to a single task defined by a fixed program in internal ROM.
An assembly of unpackaged (uncased) microcircuits and/or packaged microcircuits so constructed on a packaging interconnect structure that it is considered to be an indivisible component for the purpose of specification, testing, commerce, and maintenance.
NOTE The assembly may also include discrete devices. These and the microelectronic devices may be mounted on either one or two sides of the packaging interconnect structure, and the external terminals usually exit from one side of the assembly. Various package sizes, shapes, and external terminal forms may be used.
That field of science and engineering that deals with highly miniaturized electronic components and their use. (Ref. IEC 748-1.)
The name sometimes used for the central processing unit (CPU) of a microcomputer.
An integrated circuit capable of all of the following:
a) operating on coded instructions;
b) carrying out, in accordance with the instructions:
1) the acceptance of coded data for processing and/or storage,
2) arithmetic and logical operations on the input data together with any relevant data stored in the internal registers of the microprocessor integrated circuit and/or in external memories, and
3) the delivery of coded data; and
c) accepting and/or delivering signals controlling and/or describing the operation or state of the microprocessor integrated circuit. (Ref. IEC 748‑2.)
NOTE The instructions may be fed in, built in, or held in an internal memory.
A computer in which the microprogram (microinstructions) in the read-only memory (ROM) used for instruction decoding can be changed, thus changing the computer's instruction set.
A two-terminal device that is responsive in the microwave region of the electromagnetic spectrum, commonly regarded as extending from 1 GHz to 300 GHz.
Graphic symbol (ref. IEEE Std 315):
A specified analog value within a step that is ideally represented free of error by the corresponding digital output code.
The analog value for the center of the step excluding the steps at the two ends of the total range of analog input values.
NOTE For the end steps, the midstep value is defined as the analog value that results when the analog value for the transition to the adjacent step is reduced or enlarged, as appropriate, by half the nominal value of the step width.
Any product that is offered to customers by the manufacturer for use in US military and similar types of system applications (e.g., QPL, QML, MIL-STD-883, standard microcircuit drawings, specification or source control drawings, selected or altered item drawings).
Synonym for "gate-drain charge".
The process of eliminating redundancy in logic implementation.
(1) The lower-magnitude limit of a range of some quantity.
(2) For logic levels and temperatures only, the less positive (more negative) limit.
The minimum supply voltage at which a device is specified to operate in compliance with the applicable device specification.
The type of carrier constituting less than half of the total charge-carrier concentration.
See "metal-insulator-semiconductor technology".
An intermediate code that is absent when the changing analog input to an analog-to-digital converter causes a multiple code change in the digital output.
A diode, often associated with microwave circuits, that combines rf signals at two frequencies to generate an rf signal at a third frequency.
See "maximum material condition".
See "mode select".
See "metal-nitride-oxide-semiconductor technology".
The most frequently occurring value in a group of measurements. A measure of location.
A control input that implements special functions. It may be a dc or active input signal but is always intended to be tied to a logic high level or not connected by the user unless otherwise specified.
A representation of an electronic circuit.
A methodology that attempts to describe characteristics of a process or some aspect of a process. Once a satisfactory model is chosen, predictions about future output of the process can be made. Process variability, or error, is included to assess how well the model fits the true process and to bound future process predictions.
Input signals that, when true, select an alternative mode of operation for the device. The alternative modes available must be defined in the applicable device standard.
See "modulation-doped field-effect transistor".
A metal-semiconductor field-effect transistor in which a doped material forms a heterojunction with an undoped channel; the doped material supplies electrons to the undoped channel whose high electron mobility results in enhanced channel conductance.
NOTE 1 Typically an aluminum gallium arsenide layer is grown on an undoped gallium arsenide layer by an epitaxial growth technique.
NOTE 2 Other popularly used acronyms for this device are HEMT for high-electron-mobility transistor, SDHT for selectively doped heterostructure transistor, and TEGFET for two-dimensional electron-gas field-effect transistor.
A tool that, when given a high-level description of a desired function and relevant parameters, produces a specified implementation (for example, behavioral, structural, or geometric description, etc.) of the function to be used within an integrated circuit design.
NOTE Some functions commonly produced by module generators are RAM, ROM, ALU, and datapath.
A bag designed to restrict the transmission of water vapor and used to pack moisture-sensitive devices.
Synonym for "integrated circuit, single-chip".
A property of the transfer function that ensures the consistent increase or decrease of the digital [analog] output in response to a consistent increase or decrease of the analog [digital] input.
NOTE An intermediate increment with the value of zero does not invalidate monotonicity.
The structural characterization of an electronic component in which the current- or signal-modifying areas, patterns, or volumes have lost their identities in the integration of electronic materials, in contrast to an assembly of devices performing the same function.
The structural characterization of an electronic component in which the areas or patterns of resistive, conductive, dielectric, and active materials in or on the surface of the structure can be identified in a one-to-one correspondence with devices assembled to perform an equivalent function.
Synonym for "probability density function of the time-to-failure".
See "metal-oxide-semiconductor technology".
See "metal-oxide-semiconductor field-effect transistor".
See "metal-oxide varistor".
See "multiport DRAM".
See "multiport memory".
See "multiport RAM".
See "microprocessing unit".
See "rated moisture sensitivity level".
See "main terminal 1".
See "main terminal 2".
A multichip integrated circuit or hybrid microcircuit that contains two or more microcircuits.
A transistor having a base and two or more junctions.
Graphic symbols for triode transistors (ref. IEEE Std 315):
NOTE In the graphic symbols, the envelope is optional if no element is shown connected to the envelope.
A circuit having more than one layer of film interconnections separated by at least one insulating film or gap.
A multiple-cell upset (MCU) in which two or more error bits occur in the same word.
NOTE An MBU cannot be corrected by a simple single-bit ECC.
A single event that induces several bits in an IC to fail at the same time.
NOTE The error bits are usually, but not always, physically adjacent.
A term describing a device that has pins used for different purposes at different times as a function of one or more of its control inputs. The signal groups that are multiplexed onto a common pin set are given together, as in AA MX signifying address multiplexed with address or ADQ MX signifying address multiplexed with data in and data out.
A digital-to-analog converter having at least two inputs, at least one of which is digital, and whose analog output value is proportional to the product of the inputs.
A dynamic RAM that contains, in addition to the conventional random-access data and address port, a serial-access port that allows serial access to a portion of the stored data in a way that is independent of the normal RAM data terminals and in which simultaneous serial and random operations may be executed. This type of memory has been referred to as "Video RAM" because of its primary field of application.
Any memory array that has two or more data ports that do not have the same architecture. The most common form of MPM is one in which there is a random-access port and a serial-access port.
A RAM that has two or more ports for data, address, and control, that are not identical in nature. Normally at least one port provides parallel access while one other provides serial access. (See also "synchronous MPDRAM (SMPDRAM)".)
A pin that must be connected to a voltage that is interpreted as a logic high or "true" signal.
A pin that must be connected to a voltage that is interpreted as a logic low or "false" signal.
See "masked write transfer".
One or more symbols and/or characters intended to provide information and located on a surface of a device.NOTE A mark can give information on such items as terminal location, country of origin, manufacturer, date code, lot number, and device identification, e.g., a part number.
Solder paste, lead/terminal finish, or terminal material/alloy of the solder balls used to make the 2nd level interconnect.
The temperature that a component should not exceed during assembly as measured on the top side of the component body.
See “multi-chip package”.
The average time between failures in repairable or redundant systems.
The average time to failure for components or nonrepairable systems.NOTE The MTTF is often the reciprocal of the hazard rate when the hazard rate is described by the Poisson or equivalent exponential function, e.g., in the constant or flat portion of the useful life region of the bathtub curve.
A temperature cycle in an application resulting from a small change in the operational temperatures (e.g., due to PC program variations).
Using a program for observing, and often controlling, a device or equipment.
A package containing more than one heat source.
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