Electronics Glossary – M
Distributors of Commercial, Industrial, Medical, Automotive, and Hi-Rel Electronic Components
| Term | Definition |
|---|---|
| MAC | Moves Adds and Changes – When data and voice services (to include: outlets and cabling, patching, etc.) of a given location are moved to a new location or removed completely. |
| machine language | Assigned and defined patterns of bits which convey instructions or data to a computer. The first level of computer language. |
| macroinstruction | A short source-language statement, intelligible to a computer, that produces a variable number of instructions in machine language. Used to simplify and speed up the work of programmers. |
| Mag-Mate | A family of AMP products used to terminate magnet wire by using the insulation displacement technique. The method is unique in that cavities are provided by the customer in his products to receive the wire and terminal, and the system can be fully automated. |
| Magnet Wire | Copper or aluminum wire with electrical insulating material applied to the surface to prevent continuity between adjacent turns in a winding. |
| Magnetic Energy | The product of the flux density (B) and the (de)magnetizing force (H) in a magnetic circuit required to reach that flux density. |
| Magnetic Lines Of Force | An imaginary line representing a magnetic field, which at every point has the direction of the magnetic flux at that point. |
| Magnetic Path | The route the magnetic flux ‘flows’ in a magnetic circuit. |
| Magnetic Path Length | The length of the closed path that magnetic flux follows around a magnetic circuit. Ampere’s Law determines it. |
| main frame | See central processing unit. |
| Majority Carrier | The type of charge carrier (electron or whole) that constitutes most of the charge carriers in a semiconductor material. The majority carrier in n-type material is the electron (negative charge) and for p-type material is the hole (positive charge). |
| Manufacturing Order | MO -A series of operation-workorder cards identifying materials to be used and the type and quantity of products to be manufactured. An MO is controlled and issued by Production Control to the manufacturing operation. |
| Marking | A printed identification number or symbol applied to the surface of a wire or cable. |
| mask | A patterned medium placed between a substrate and a process source in order to confine the effects of the process to selected portions of the substrate. |
| mass termination | A means of terminating multiple conductors to an identical number of contacts through one complete cycle of applicator tooling. The contacts are an insulation displacement type and the conductors may be discrete wires, round conductor ribbon cable, or flat cable. Special application tooling is required. |
| master pattern | A 1:1 scale pattern used to produce the printed circuit within the accuracy specified on the master drawing. |
| Master/Slave Operation | Wire used to create a magnetic field such as those in magnetic components (inductors and transformers). Magnet wire is nearly 100% copper and must be made from virgin copper. It is covered with a number of difference organic polymer film coatings. |
| matched impedance | The coupling of two circuits in such a way that the impedance of one circuit equals the impedance of the other. |
| mate | To join two connectors in a normal engaging mode. |
| Material dispersion | Dispersion resulting from the different velocities of each wavelength in an optical fiber. |
| Material Modification Code | MOD Code – A code designating a particular stage in the production process. Most MOD codes describe the way the product is packaged. |
| mating face | interface |
| matrix | grid |
| Maximum Ambient Operating Temperature | The highest ambient temperature at which a circuit is expected to operate. |
| Maximum Ambient Operating Temperature | The highest ambient temperature at which a circuit is expected to operate. |
| Maximum Device Voltage | The highest voltage that can safely be dropped across a PolySwitch device in its tripped state under specified fault conditions. |
| Maximum Fault Current | The rated maximum value of peak pulse current of specified amplitude and wave shape that may be applied without damage. |
| Maximum Interrupt Current | The highest fault current that can safely be used to trip a PolySwitch device under specified conditions. Typically the lower the voltage dropped across the PolySwitch device in its tripped state, the higher the maximum interrupt current. Maximum interrupt currents are usually shown in this Databook at the maximum voltage. It may be possible to use a PolySwitch device at a higher interrupt current, but each such use must be individually qualified. |
| Maximum Interrupt Voltage | The highest voltage that can safely be dropped across a PolySwitch device in its tripped state under specified fault conditions. |
| Maximum Load | Highest amount of output load allowable under the continuous operating specifications of a converter. |
| Maximum Operating Voltage | The maximum voltage across a PolySwitch device under a typical fault condition. In many circuits, this is the voltage of the power source in the circuit. It may be possible to use a PolySwitch device at a higher voltage, but each such use must be individually qualified. |
| Maximum Output Resistance | The resistance of a device at a specified voltage. |
| Maximum Power Dissipation | An inductor’s ability to handle the heat generated by operating at maximum current at an ambient temperature, expressed in Watts (W) or milliwatts (mW). This is a function of the body area of the inductor, core material used, and varies for shielded vs. unshielded. |
| Maximum Resistance | The maximum resistance of a PolySwitch device at room temperature one hour after being tripped or after reflow soldering. |
| Maximum Resistance | The maximum resistance of a PolySwitch device at room temperature one hour after being tripped or after reflow soldering. |
| Maximum Switching Current | The maximum current that a device switches at safely without damage. |
| Maximum Voltage | The highest voltage that can safely be dropped across a PolySwitch device in its tripped state under specified fault conditions. |
| Maxwell | The unit of magnetic flux in the CGS system. One Maxwell = 10-8 webers. |
| Mbps | A data rate. Megabits, or millions of bits, per second. |
| MCM | Thousand circular mils. Above 4/0 AWG wire, circular mil areas (CMA) are used rather than AWG wire size. See kcmil. |
| MCNS | multimedia cable network system |
| MDS | microwave distribution system |
| MDU | multi-dwelling unit |
| Mean Time Between Failure | MTBF – Unit of measure, expressed in hours, that gives the relative reliability of a converter. MTBF data is based upson actual operating data (demonstrated) or derived per the conditions of MIL-HDBK-217F (calculated). |
| Mean Time to Failure | MTTF – The measured operating time of a system or component divided by the number of failures that occurred during that time |
| Mechanical Life | This is the number of operations which a relay can be expected to perform while maintaining mechanical integrity. Mechanical life is normally tested with no load or voltage applied to the power contacts and is established using various methods including Weibull analysis. |
| mechanized assembly | The joining together of parts and/or subassemblies with the aid of operators and semiautomatic equipment. |
| Media I | A 12-row, 80-column card used to program a device. The card measures 3.250 in. by 7.375 in. and the coded program or data is placed on the card in the form of small rectangular punched holes. It is loosely referred to as an IBM card. |
| Media II | A 6-row, 90-column card used to program a device. The card measures 3.250 in. by 7.375 in. and the coded program or data is placed on the card in the form of small round punched holes. |
| medium-scale integration | MSI – A term describing the level of complexity or size of an integrated circuit. The monolithic integrated circuit has from 10 to 100 gates and falls in size between small-scale integration (SSI) and large-scale integration (LSI). |
| mega | A prefix that indicates a factor of one million or 106, abbreviated as “M.” |
| Megarad | A unit for measuring radiation dosage. |
| melt index | Extrusion rate of a thermoplastic material through an orifice of specified diameter and length under specified conditions of time, temperature, and pressure. |
| Melt/Flow Index | Measurement of the flow of thermoplastic material under given conditions of temperature and pressure. Expressed as grams per unit of time. |
| Melting Point | The temperature at which crystallinity disappears when crystalline material is heated. |
| memory | That portion specially designed to receive and store information for use at a later time. Also called storage. |
| MEO | Medium Earth Orbit (satellites) (See also GEO and LEO) |
| message | A communication of information or advice from a source to one or more destinations in suitable language or code. In telegraphic and data communications a message is composed of three parts as follows: 1) A heading containing a suitable indicator of the beginning of the specific message together with information on any or all of the following: the source and destination, data and time of filing, and routing or other transmission information. 2) A body containing the information or advice to be communicated. 3) An ending containing a suitable indicator of the conclusion of the specific message, either explicit or implicit. |
| Metal Semiconductor Field Effect Transistor | MOSFET – A field effect transistor (FET), often made of gallium arsenide, that uses a metal-on-semiconductor gate. See also “gallium arsenide field effect transistor” and “Metal Oxide Semiconductor Field Effect Transistor.” |
| metallization | A metal film selectively deposited on a substrate to serve as conductive interconnections between the elements of the integrated circuit, and as points (pads) for external connections. |
| Metal-Oxide-Semiconductor-Field-Effect-Transistor | A transistor that consists of electrodes (the source and drain) placed at opposite ends of a silicon channel. On top of the channel and between the electrodes an insulating layer of silicon dioxide is formed, on top of which a metal pad (the gate) is deposited. An electric field is induced into the channel as a result of a potential that is externally applied to across the source and gate. This field modulates the resistance of the channel between the drain and source. |
| metric prefixes | A series of prefixes used in the metric system to modify a unit of measure. The most commonly used in electronics are as follows: giga (G) 109; mega (M) 106; kilo (k) 103; centi (c) 10-2; milli (m) 10-3; micro (m) 10-6; nano (n) 10-9; pico (p) 10-12 |
| Metropolitan Area Network | MAN – A data communication network covering the geographic area of a city. Often used by a CAP to carry backbone traffic in their serving area. |
| mho | Unit of conductance. Reciprocal of an ohm. One ampere of current passing through a material under a potential difference of one volt provides one mho of conductance. Also called siemens. |
| MHz | Megahertz.Millions of cycles (Hertz) per second. A frequency or frequency range (bandwidth) through which a cabling system is specified. |
| MIC | Microwave Integrated Circuit – A circuit that is contained either on a single die or in a single package, intended to operate at microwave frequencies |
| micro | A prefix that indicates a factor 10-6, abbreviated as “m.” |
| microcomputer | A vague term, usually referring to a computer system that uses a microprocessor as the CPU. Also used to mean an integrated circuit having all the parts of a computer: CPU, memory, I/O, etc, although on a less grand scale. |
| microelectronics | The art of electronic equipment design and its construction, which utilizes any of the microminiaturization schemes. This art of electronics deals with microminiature parts, subassemblies, and assemblies. |
| microminiature circuitry | Circuitry fabricated in accordance with microminiaturization techniques. |
| microminiaturization | The technique of packaging a microminiature part or assembly composed of elements radically different in shape and form factor. Electronic parts are replaced by active and passive elements, through use of fabrication processes such as screening, vapor deposition, diffusion, and photoetching. |
| Micron | One-millionth of a meter; A micrometer. |
| microprocessor | A single chip or small group of chips that contain all the functions of a computer processor; does not include peripherals. |
| Microstrip | An unbalanced transmission line structure that consists of a ground plane on the back side of a printed circuit board, the dielectric material of the printed circuit board and a narrow strip on the top side of the circuit board. The impedance of microstrip is determined by the dielectric constant and the thickness of the dielectric and the width of the strip. |
| Microwatt | One millionth of a watt. |
| Microwave Distribution System | A network of microwave radio links used to distribute data or video signals to subscribers. |
| Microwave Integrated Circuit | MIC – A circuit that is contained either on a single die or in a single package, intended to operate at microwave frequencies |
| microwaves | That portion of the electromagnetic spectrum lying between the far infrared and conventional radio frequency portion. Frequency range extending from 1 GHz to 300 GHz. Microwaves are usually used in point to point communications because they are easily concentrated into a beam. |
| MID | Mode field diameter. |
| migration | The movement of some metals from one location to another, notably through pores in a metal surface plating. This can be either the movement of the intermediate plating or the base metal to the surface – which in turn produces insulating films. |
| Mil | A unit equal to one onethousandth of an inch (.001″), equivalent to 0.0254 millimeters or 25.4 micrometers; used in measuring the diameter of a conductor or thickness of insulation over a conductor. |
| Military Specification | MIL-SPEC – Military requirements; the demand imposed upon the system/device to meet a military operational need. |
| Milking Off | Action that occurs when the inner layer (the encapsulant or adhesive) of the tubing or molded part acts as a lubricant, allowing the tubing to slip off the substrate (because the tubing wants to recover to a smaller diameter). |
| milli | A prefix meaning 10-3, or one thousandth. One millivolt would be 0.001 volt. Abbreviated as “m.” |
| millisecond | One thousandth of a second. |
| Milliwatt | One-thousandth of a watt. |
| MIL-SPEC | Military Specification – Military requirements; the demand imposed upon the system/device to meet a military operational need. |
| MIM | Metal-insulator-metal, a common structure of series capacitors on integrated circuits. |
| miniaturization | The technique of packaging by reducing size and weight of electronic parts in step with the change from vacuum tubes to transistors and diodes. |
| minicomputer | A computer system midway in price and performance between mainframe and microcomputer. |
| Minimum Discernable Signal | The smallest input signal level to a receiver that will produce a discernable output signal. |
| Minimum Full Recovery Temperature | The minimum temperature required to fully shrink a product, that is, for the product to recover completely. |
| Minimum Load | Minimum amount of output load required on a converter in order to maintain normal continuous operating specifications. Usually associated with PWM (Pulse Width Modulation) controlled converters. |
| Minimum Operating Temperature | Minimum ambient temperature at which a converter will start and operate within specifications. |
| Minimum Shrink Temperature | The minimum temperature at which a product begins to recover. |
| Minority Carrier | The type of charge carrier (electron or whole) that does not constitutes most of the charge carriers in a semiconductor material. The minority carrier in n-type material is the hole (positive charge) and for p-type material is the electron (negative charge). |
| Misalignment loss | The loss of power resulting from angular misalignment, lateral displacement, and end separation. |
| Mismatch | The degree to which the impedance of a component differs from the transmission line or component to which it is connected. The degree to which the lattice constant of one crystalline semiconductor differs from the lattice constant of another. |
| Mismatch Loss | The power that a device could absorb if its impedance were perfectly matched to that of its surroundings divided by the power that it does absorb. |
| Mixer | A three port device that employs at least one component with nonlinear impedance to perform time domain multiplication of signals incident on two of the ports, typically designated RF input and LO input. Among the products of this multiplication at the third port are signals whose frequencies are the sum and the difference of the LO and RF frequencies (see “up converter” and “down converter”). |
| MLT | The mean-length-turn of wire for a core. |
| MMDS | Multipoint microwave distribution system (also known as wireless cable). |
| MMIC | Monolithic Microwave Integrated Circuit |
| mnemonic language | A programming language that is based on easily remembered symbols and that can be assembled into machine language by the computer. |
| MO | Manufacturing Order – A series of operation-workorder cards identifying materials to be used and the type and quantity of products to be manufactured. An MO is controlled and issued by Production Control to the manufacturing operation. |
| MOD Code | Material Modification Code – A code designating a particular stage in the production process. Most MOD codes describe the way the product is packaged. |
| modal dispersion | The spreading of a light signal in a fiber as a result of the rays following different paths (or modes) down the fiber. This limits the number of pulses that can be sent per second. In multimode fiber (larger core than single mode) rays take many different zigzag paths along the fiber, requiring more time for some signals to arrive at the other end, which causes a running together of on-off digital pulses. |
| Mode | In guided-wave propagation, such as through a waveguide or optical fiber, a distribution of electromagnetic energy that satisfies Maxwell’s equations and boundary conditions. Loosely, a possible path followed by light rays. |
| Mode of Failure | The manner in which a failure occurs. Reason for which a converter either does not meet or stops meeting its specified parameters. |
| modem | A unit that transmits signals over a telephone line. |
| modifier | Additive to a resin compoundwhich changes the compound’s properties or processing characteristics. |
| modular | (1) A modular connector is one in which similar or identical sections can be assembled together to provide the best connector type or size for the application (2) Being composed of modules dimensioned in accordance with a set of prescribed size increments. |
| Modular jack | The standard female connector for twisted pair cable. A “telephone jack”. |
| Modular plug | The standard male connector for twisted pair cable. A “telephone plug”. |
| modulate | To vary the amplitude, frequency, or phase of an oscillation rate – usually at a signal frequency. |
| Modulation | The process by which some characteristic of a carrier wave is modified in accordance with an intelligence signal. Commonly used modulation methods include but are not limited to amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), frequency shift keying (FSK) and quadrature amplitude modulation (QAM). |
| Modulation Frequency | The frequency or frequency interval of the intelligence signal used to modulate a carrier wave. |
| Modulation Sensitivity | For a voltage controlled oscillator that is frequency modulated, the change in VCO frequency divided by the magnitude of the control voltage that produced the change in VCO frequency. Modulation sensitivity is expressed in terms of MHz per volt for RF/microwave VCO’s. |
| module | (1) A family of inserts which are uniform in external dimension, but may accept different types of contacts, or have different contact densities or configurations. In “G” series connectors, modules are interchangeable within the shells of that line. See also insert and shell. (2) Encapsulated DC-DC converter |
| modulus | Defines the capability of a device in terms of number of distinct states. For example, a modulo-10 counter has a modulus of 10 and, therefore, has 10 distinct states. |
| mold | A hollow form which imparts to the material within a final shape as a finished piece. Various types are used in compression molding, injection molding, transfer molding, and other processes. |
| molecular electronics | The science of applying solidstate phenomenon in the performance of electronic functions. That branch of electronics which deals with production of complex electronic circuits in microminiature form, by producing semiconductor devices and circuit elements integrally while growing multizoned crystals in a furnace. |
| MOM | message-oriented middleware |
| monolithic integrated circuit | Monolithic means “from one stone,” hence a single silicon chip containing an integrated circuit. |
| Monolithic Microwave Integrated Circuit | A semiconductor circuit that contains more than one component and is fabricated on a semiconductor die. |
| monomer | The simple, unpolymerized form of a compound which is the building block of a polymer. |
| Monotonicity | The degree to which the slope of a function does not change sign |
| MOS IC | Metal-oxide-semiconductor integrated circuit. A digital IC whose transistors are all (or nearly all) composed of MOS transistors. MOS ICs are typically slower than TTL, but offer greater packaging density and lower power consumption. Varieties include PMOS, NMOS, and CMOS. |
| MOS transistor | Metal-oxide-semiconductor. A class of transistors that operate by means of an electric field produced by a voltage on a metal plate called the gate. The field acts through a thin layer of oxide insulation on a semiconductor channel, controlling its depth and therefore the current through the channel. See also FET, FET resistor, IGFET, CMOS, PMOS, and NMOS. |
| MOSFET | Metal-Oxide-Semiconductor-Field-Effect-Transistor – A transistor that consists of electrodes (the source and drain) placed at opposite ends of a silicon channel. On top of the channel and between the electrodes an insulating layer of silicon dioxide is formed, on top of which a metal pad (the gate) is deposited. An electric field is induced into the channel as a result of a potential that is externally applied to across the source and gate. This field modulates the resistance of the channel between the drain and source. |
| motherboard | A pc board on which connectors are mounted and interconnections are made with another pc board (daughterboard). A board-to-board application with the motherboard usually being the larger and containing other electronic subassemblies. |
| mother-daughter board connector | A connector designed for interconnection of printed circuit boards, typically with perpendicular engagement. |
| MPEG | moving pictures experts group |
| MPLS | multi-protocol label switching |
| MPP Core | MPP is an acronym for molypermalloy powder. It is a magnetic material that has an inherent distributed air gap. The distributed air gap allows the core to store higher levels of magnetic flux when compared to other magnetic materials such as ferrites. This characeristic allows a higher DC current level to flow through the inductor before the inductor saturates. The basic raw materials are nickel, iron and molybdenum. The ratios are: approximately 80% nickel, 2% -3% molybdenum, and the remaining is iron. The manufacturing process includes an annealing step as discussed in the Kool Mu (r) definition. MPP stores higher amounts of energy and has a higher permeability than Kool Mu (r) Cores are offered in 10 or more permeability selections. The core characteristics allow inductors to perform very well in switching power applications. Since higher energy can be stored by the core, more DC current can be passed thorugh the inductor before the core saturates. The cost of MPP is significantly higher than Kool Mu (r) , powdered irons and most ferrite cores with similar sizes (See saturation current and Kool Mu (r)) |
| MS | Mobile system (eg. cellphone network) |
| MSAS | MTSAT Satellite based Augmentation System (See also WAAS, EGNOS) |
| MSI | See medium-scale integration. |
| MTBF | Mean Time Between Failure – Unit of measure, expressed in hours, that gives the relative reliability of a converter. MTBF data is based upson actual operating data (demonstrated) or derived per the conditions of MIL-HDBK-217F (calculated). |
| MT-RJ | A small form factor, dual fiber connector. |
| MTSAT | Multi-Task Satellite system |
| MTTF | mean time to failure – The measured operating time of a system or component divided by the number of failures that occurred during that time |
| MTU | multi-tenant unit |
| multichip IC | A special form of hybrid where two or more semiconductor chips are attached separately to a substrate. |
| Multiconductor | More than one component within a single-cable complex. |
| Multifilar Winding | A winding technique in which a single turn consists of two or more strands of magnetwire operating in parallel. This reduces some of the second order effects associated with a single strand of wire, including skin effect downfalls and winding ease. |
| multilayer board | A printed circuit board having traces not only on both sides but sandwiched between board layers. |
| Multimate | The standardization of given characteristics in several different contacts and a variety of connectors. By this means, contacts from varying price ranges and with differing performance characteristics (power, signal, optic, and coaxial) can be used interchangeably in a number of different connectors. |
| Multimode | A type of optical fiber in which the light travels in multiple paths. Utilizes LEDs or lasers as light sources. |
| multimode fiber | A fiber that allows a light signal to take various paths to arrive at the end of the fiber causing some light rays to arrive later than others. |
| Multiple-Conductor Cable | A combination of two or more components cabled together. |
| multiplex | The simultaneous transmission of two or more signals using a common carrier wave or a single path in a transmission system. Examples include the transmission of stereophonic fm broadcasts or multiple voices over a single telephone line. |
| multiplexer | MUX – An electronic device normally used to scan a number of input terminals and receive data from, or send data to, the same. Multiplexers are normally one of two types: 1) The cyclic type which continually and sequentially looks at each input for a request to send or receive data. 2) The random type which waits in a “rest” position until other circuitry notifies it of a request to receive or send data. |
| Multiplier | A circuit whose output frequency is an integral multiple of the input frequency and whose output signal is coherent with the input signal. The critical component in a multiplier is typically a step recovery diode, Schottky diode, FET or varactor diode. |
| multiprogramming | A technique for handling numerous routines or programs in a manner that is seemingly simultaneous. This is done by overlapping or interleaving their execution (ie permitting more than one program to time share machine components). |
| Multi-user outlet | A work area outlet designed to support multiple users. Also called multi-user telecommunications outlet assembly or MUTOA. |
| MUTOA | A work area outlet designed to support multiple users. Also called multi-user telecommunications outlet assembly or MUTOA. |
| MUX | multiplexer – An electronic device normally used to scan a number of input terminals and receive data from, or send data to, the same. Multiplexers are normally one of two types: 1) The cyclic type which continually and sequentially looks at each input for a request to send or receive data. 2) The random type which waits in a “rest” position until other circuitry notifies it of a request to receive or send data. |
| mW | Microwatt |
| MW | Milliwatt |