Glossary of Terms
| Term | Definition |
|---|---|
| "B" stage | The condition of a resin polymer when it is more viscous, with higher molecular weight, being insoluble but plastic and fusible. |
| B & S | Brown & Sharpe Gauge, a wire diameter standard that is the same as AWG. |
| B channel | In ISDN, a full duplex, 64 kbps channel sending data. |
| back mounted | A connector attached to the inside of a panel or box with its mounting flanges inside the equipment. |
| backboard | Refers to a plywood panel mounted on the wall of a telecom closet. Used to mount the cross connect. |
| backbone | The part of the network that carries the heaviest traffic. It is the main trunk cable from which all connections to the network are made. |
| backbone cabling | Cabling between floors in a building or between buildings in a campus. |
| backbone network | The main artery or link for a private or public network. Typically the backbone carries the lion's share of traffic (data, voice, video or some combination), is capable of carrying significant bandwidth and it is the network to which small/remote networks/links are attached. |
| back-mounted | A termination assembly mounted from the inside of a panel or box with its mounting flange inside the equipment. |
| backplane | Area of a computer or other equipment where various logic and control elements are interconnected. |
| backscattering | The return of a portion of scattered light to the input end of a fiber; the scattering of fight in the direction opposite to its original propagation. |
| bail lock | Spring members which are attached to the connector flanges and used to hold mated connectors together. |
| balanced line | A two-conductor line in which both conductors have the same impedance with respect to ground. Since noise pickup is equal on both conductors, common-mode interference is cancelled at the load. |
| balanced mixer | (1) A type of mixer that forms from two signals A and B third signal C having the form C = (a + A)(b + B). "Single balanced" implies a = 0, and b ¹ 0. "Double balanced" implies a = b = 0. Such mixers can suppress an RF carrier and / or local oscillator in their output spectrum. (2) A hybrid junction circuit with nonlinear impedances, typically Schottky diodes or FET's, driven by a single RF source and a local oscillator (LO) source to produce an intermediate frequency (IF) signal. |
| balanced transmission line | A transmission line or circuit in which two branches are electrically alike and symmetrical with respect to a common reference point, usually ground. An applied signal at the input relative to the reference leads to signals at equivalent points in the circuits that have opposite polarity and equal amplitude. |
| ball bond | A type of thermocompression bond in which a gold wire is flame-cut to produce a ball-shaped end. The ball-shaped end is then bonded to a metal pad by pressure and heat. |
| ballast | An impedor, used to stabilize the current in the circuit. |
| balun | Balanced/Unbalanced - an impedance matching device to connect balanced twisted pair cabling with unbalanced coaxial cable. |
| balun filter | Input line filter often used on DC-DC converters that include a differential wound transformer. Balun filters present a low impedance to differential mode signals and a high impedance ot common mode signals. |
| band marking | A continuous circumferential band applied to a wire at regular intervals for identification. |
| Band Pass | The frequency range over which an inductor or capacitor exhibits a low impedance. |
| Band Pass Filter | BPF - A reactive circuit which rejects signals whose frequencies are outside of its passband 3 dB point frequencies and propagates signals whose frequencies are within B189the 3 dB point frequencies. |
| Band Reject Filter | BRF - A reactive circuit that rejects signals whose frequencies are within its 3 dB point frequencies and propagates signals whose frequencies are outside its 3 dB point frequencies. |
| Band Stop | The frequency range over which an inductor or capacitor exhibits a high impedance. |
| bandwidth | 1) Indicates a range of frequencies. For example, for a bandpass filter, it is the frequencies passed. For a transmitter and receiver, it is the frequencies that can be transmitted or received. For a transmission system, it is typically the highest frequency transmittable (lower ones can usually be handled). 2) A term used to describe the capacity or amount of traffic (data, voice or video) a certain communications line is capable of accommodating. |
| Bandwidth-limited operation | The condition in a fiber-optic link when bandwidth, rather than received optical power, limits performance. This condition is reached when the signal becomes distorted, principally by dispersion, beyond specified limits. |
| Bare Conductor | A conductor not covered with insulating material. |
| barrel | The portion(s) of a terminal, splice, or contact that is crimped. When designed to receive the conductor, it is called the wire barrel. When designed to support or grip the insulation, it is called the insulation barrel. Wire and/or insulation barrels may be either "open" or "closed" in design. Closed barrels resemble a hollow cylinder into which the wire must be inserted. Open barrels are formed into an open "U" and are common to most strip terminals manufactured by AMP Incorporated. |
| barrier block | An insulated mounting for terminal connections. Barrier blocks are available with threaded holes to accept threaded screws, or with threaded studs to accept fastening washers and nuts. |
| Barrier Height | The difference between the metal work function and the semiconductor electron affinity in a rectifying metal-semiconductor junction (see Schottky diode). The barrier height of a Schottky junction determines the voltage current characteristics of that diode. This can be important because it determines the local oscillator power necessary to bias the junction to its optimum non-linear operating point. As an approximation, the optimum local oscillator power will increase as the square of the barrier height, if the same mixer circuit characteristics and junction capacitance values are used. |
| base | (1) The region of a bipolar transistor that separates the emitter and collector regions. Majority carriers injected into the base from an external source controls the amount of current that flows in the emitter and collector regions. (2) An insulating support for the printed circuit pattern. It may be of flexible or rigid material. |
| Base Current | The current that flows into the base of a bipolar transistor. |
| base metal | Metal from which the product or accessory is made, and on which one or more platings or coatings may be deposited. |
| Base Plate | Substrate to which circuit components are mounted or, a metal plate to which the converter is attached. Normally used to draw heat away from critical circuit components. Also see Heat Sink. |
| Base Plate Temperature | Temperature of the case when the converter and surrounding system are operating normally. Often used as a specification for DC-DC converters with extended temperature ranges. Sometimes referred to as Case Temperature. |
| Base Resistance | The resistance of a PolySwitch device under specified conditions (e.g., 20¡C), before connection into a circuit. Devices of a particular type will be delivered with a range of resistances; therefore, a minimum value, Rmin, and/or a maximum value, Rmax, are often given. |
| Base Transceiver Station (or Base Station) | A high power transceiver, typically located at the geometric center of a cell, which links subscriber radios such as cellular phones or modems to the landline communication infrastructure. |
| Baseband | Transmission scheme in which the entire bandwidth, or data-carrying capacity, of a medium (such as coaxial cable) is used to carry a single digital pulse, or a signal, between multiple users. Because digital signals are not modulated, only one kind of data can be transmitted at a time. Contrast with broadband. |
| baseband signal | A signal transmitted at its original frequency, without modulation. |
| BASIC | Beginners All-purpose Symbolic Instruction Code. A simple, procedural programming language, popular in timesharing and in microcomputers. |
| Basic Encoding Rate (BER) | Rule of encoding data units described in ANS.1. |
| Basic Rate Interface (BRI) | Reference ISDN. |
| Batch Number | Lot number |
| Battery Backup | Subsystem for electronic equipment that provides power in the event of input power loss. Battery backed systems are a common application are for DC-DC converters. |
| baud | A unit of signaling speed equal to the number of signal symbols per second, which may or may not be equal to the data rate in bits per second. |
| bayonet coupling | A quick coupling device for circular plug and receptacle connectors. Pins projecting from the outside of the cylindrical receptacle engage with corresponding cam slots in the bayonet plug. Mating is accomplished by rotation of the two parts under pressure. |
| bcd | binary coded decimal - A coding system in which each decimal digit from 0 to 9 is represented by four bits. |
| beam lead | (1) A metallized termination that extends beyond the edge of a semiconductor die. (2) A semiconductor die with metallized terminations that extend from the edges of the die. A beam lead device is mechanically and electrically attached to a circuit by means of these leads. |
| Beaming | Crosslinking by means of high-energy electrons. |
| Beamsplitter | An optical device, such as a partially reflecting mirror, that splits a beam of light into two or more beams and that can be used in fiber optics for directional couplers. |
| Bel | The common logarithm of the ratio of two amounts of power. The abbreviation for Bel is "B." If P1/P2 is the ratio of two powers, then this ratio expressed in Bels, N, is N = log10 (P1/P2). |
| bellmouth | Flared at the mouth. The rear of a properly crimped wire barrel will have a slight flare (bellmouth) to relieve the strain on the wire strands as they leave the area of high compression and take their natural "lay." Bellmouth may also be present on the front of the wire barrel. |
| Bend loss | A form of increased attenuation in a fiber that results from bending a fiber around a restrictive curvature (a macrobend) or from minute distortions in the fiber (microbends). |
| BER | Bit Error Rate - The ratio of the number of bits in a data transmission that are incorrectly received to the number of bits received. The BER is typically expressed in parts per million and is used as an indication of reliability. |
| bezel | The frame (usually plastic) that holds the keyboard together and provides for key mounting and a general framework. |
| B-H Curve | Curve to show characteristics of a magnetic material, in terms of magnetizing force (H) and resulting flux density. |
| BH Loop | A hysteresis loop showing magnetic characteristics of a magnetic material as an alternating current is applied. |
| BHMAX (Maximum Energy Product) | Indicates the maximum energy that a magnetic material can supply to an external magnetic circuit when operating at the Bd, Hd point on its demagnetization curve, measured in megaGauss-Oersteds (MGOe) or kiloJoules per cubic meter (kJ/m3). |
| Bias | The control voltage and/or current applied to a device that establishes or facilitates proper operation. |
| Bias Current | The (typically direct) current applied to an electronic device to control or facilitate its operation. |
| bias voltage | A voltage used to establish the desired dc operating voltage for a semiconductor. Generally refers to the base voltage. |
| BiCMOS | A silicon process for fabricating integrated circuits that combine bipolar transistors and complementary metal oxide semiconductor devices on the same chip. The bipolar transistors provide high speed and can drive loads external to the IC, while the CMOS devices provide very high density and low power dissipation. Devices or IC's that use this process. |
| Bifilar Winding | Two strands of magnet wire wound side-by-side. |
| bifurcated contact | A spring contact that has been split lengthwise to provide two independent contact surfaces. This redundancy assures two points of contact with the mating conductor element. |
| Bilateral | A circuit or component whose operation is unchanged when the input and output ports are interchanged |
| binary | The binary number system has only two digits - 0 and 1. |
| binary code | A code in which each element may be either of two distinct values (eg the presence or absence of a pulse). |
| binary coded decimal | A coding system in which each decimal digit from 0 to 9 is represented by four bits. |
| Binder | A spiral wrapping of a thread to hold together the members of a cable. |
| bipolar | (1)Of or pertaining to two opposite polarities. (2) A semiconductor having at least two pn junctions and working through both minority and majority carriers (holes and electrons). Npn and pnp transistors, and related ICs such as TTL and ECL, are bipolar. |
| Birmingham Wire Gauge | BWG - The Birmingham Wire Gauge was used extensively in Great Britain and the United States for many years, but is now obsolete. Its uses have persisted, however, for certain purposes including galvanized steel wire for cable armor. |
| bistable | Having two stable electrical states. A bistable circuit will remain in either state indefinitely, until an external signal switches it to the other state. A flip-flop is an example of a circuit with this property. |
| bit | The smallest element of information in binary language. A contraction of Binary digit. These characters in system language signify "on" and "off" (1 and 0). Word length, memory capacity, etc, can be expressed in number of bits. |
| bit density | Number of bits that can be placed, per unit area or volume, on a storage medium (eg bits per inch of magnetic tape). |
| Bit Error Rate | BER - The ratio of the number of bits in a data transmission that are incorrectly received to the number of bits received. The BER is typically expressed in parts per million and is used as an indication of reliability. |
| Bits Per Second (bps) | The number of bits passing a point every second. The transmission rate for digital information. |
| black box | A term used loosely to refer to any assembly or subassembly, usually electronic, that can readily be installed or removed from a specific location in a larger system by an operator not familiar with its detailed internal structure. |
| BLEC | building local exchange carrier |
| blistering | A localized swelling and separation between any of the layers of the printed circuit base laminate and/or between the laminate and the metal cladding. Also, similar swelling in molded parts. |
| block | (1) Typically a contact housing used in a modular connector (2) A group of words or characters considered or transported as a unit, particularly with reference to input and output. |
| blocking | The sticking together of insulated wires; usually caused by heat. |
| Bluetooth | A transmission standard operating at 2.4 GHz for connecting telephones, computers and other devices without the use of wires. |
| BNC | A bayonet style coaxial connector. |
| BNC Series | A radio frequency connector covered by Military Specification. It has an impedance of 50 ohms, and is designed to operate in the 0 to 4 GHz frequency range. Quick connect/disconnect is featured by a pin and cam bayonet coupling. |
| bobbin | A part having one or more flanges connected to a barrel in a spool configuration. It may be any one of a number of round, square, oval, or rectangular configurations on which magnet wire is spirally wound into a coil. |
| bobbin core | A core with the shape of a bobbin or spool which contains flanges. Bobbin cores are available with and without leads and in the axial and radial form. |
| body | (1) Main, or largest, portion of a connector, to which other portions are attached. (2) A protective covering of resilient material over any portion of a cable, wire termination, or termination assembly in addition to normal jacketing of insulation, to prevent entry of moisture. Also, a form for holding potting compound. |
| bond pull | A test used to determine the integrity of a wire bond, in which mechanical stress is applied to the wire in the direction that would pull it from the semiconductor bonding area. Bond pull tests can destroy the wire bond, in which case the wire is pulled until it breaks or pulls free from the bonding area, or nondestructive, in which case a fixed amount of force is applied to the wire. |
| bond strength | A measure of the stress required to separate a layer of material from the base to which it is bonded. It is measured in pounds per square inch of width (peel strength) obtained by peeling the layer, and in pounds per square inch (pull strength) obtained by a perpendicular pull applied to a surface of the layer. Often used to describe the adhesion of a printed circuit path to the basic board material. |
| bond wire | A conductive wire that connects a semiconductor die to an external circuit. |
| bonding | The very low resistance fusion of a conductive wire to a metallized area of a semiconductor die. For most RF/microwave semiconductors, the wire and the topmost layer of metal on the semiconductor die are very pure gold (Au). |
| bonding area | A metallized region on the top surface of semiconductor die by which electrical connection to an external circuit is made by means of a bond wire. |
| bonding pad | Metallized areas on the surface of a semiconductor device, wafer, or die, to which electrical leads may be connected or probes applied. Also referred to as bonding area. |
| bonding temperature | Temperature above which adhesive melts and flows sufficiently to form an adhesive bond between substrates. |
| Boolean algebra | The algebra of logic named for George Boole. Similar in form to ordinary algebra, but with classes, propositions, yes/no criteria, etc for variables rather than numeric quantities. It includes the operators AND, OR, NOT, IF, EXCEPT, THEN. |
| boost regulator | A basic DC-DC switching converter topology that takes an unregulated input voltage and produces a higher regulated output voltage. The higher output voltage is achieved by storing energy in an input inductor and then transferring the energy to the output by turning a shunt switch (transistor) on and off at a fast rate. |
| boot | (1) Protective covering over any portion of a cable, wire, or connector in addition to the normal jacketing or insulation. (2) A form placed around wire termination of a multiplecontact connector to contain the liquid potting compound before it hardens. (3) A protective housing usually made from a resilient material to prevent entry of moisture into a connector. |
| bootstrap | (1) A feedback technique which tends to improve linearity and input impedance of circuits operating over a wide range of input signal. (2) A short sequence of instructions, usually a loader program, which entered into the computer's programmable memory will operate a bulk storage memory device to load the programmable memory with a larger, more sophisticated program. |
| bounce time | The time interval between when the contact first makes, and when the last contact make occurs. |
| BPF | Band Pass Filter - A reactive circuit which rejects signals whose frequencies are outside of its passband dB point frequencies and propagates signals whose frequencies are within the dB point frequencies. |
| bpi | Bits per inch - measurement of bit density |
| BPSK | Binary Phase Shift Key modulation. |
| braid | A woven metallic or fiber layer used as a shield covering for an insulated conductor or group of insulated conductors. When flattened, a metal weave may be used as a grounding strap. |
| Braid Angle | The angle between the braid strands and the axis of the cable. |
| branched | Chemistry term referring to side chains attached to original chain (in a direction different from that of the original chain) in molecular structure of polymers. |
| breadboard | A test board on which components are mounted to test the feasibility of prototype circuitry. |
| breadboard circuit | A circuit simulation using discrete components or partially integrated components to prove feasibility of a circuit. |
| breakdown voltage | (1)The voltage at which an insulator or dielectric ruptures, or at which ionization and conduction take place in a gas or vapor. (2) The reverse voltage at which avalanche breakdown occurs in a semiconductor. (3) Maximum AC or DC voltage that can be applied from the input to output (or chassis) of a converter without causing damage. |
| Breakout | A region in a harness assembly where a wire or a group of wires is detached to form a separate, terminated branch. Also known as a transition. |
| Breakover Current | Instantaneous current flowing at the breakover voltage, VBO. |
| Breakover Voltage | Maximum voltage across a SiBar device at breakdown measured under a specified voltage rate of rise and current rate of rise. |
| breakpoint | A point of special interest in a computer routine requiring human communication prior to continuation. |
| BRF | Band Reject Filter - A reactive circuit that rejects signals whose frequencies are within its 3 dB point frequencies and propagates signals whose frequencies are outside its 3 dB point frequencies. |
| bridge converter | Switching converter topology that employs four switching elements (full bridge) or two switching elements (half-bridge). This topology is more often used in off-line supplies rather than DC-DC converters. Bridge converters provide high output power and low ripple, but are significantly more complex than other types of converter topologies and thus are more expensive and prone to failure. Also see Boost Regulator, Buck Regulator, Flyback Converter, Foward Converter, Push-Pull Converter and Resonant Converter. |
| bridge/router | A device that can provide the function of a bridge, router or both concurrently. Bridge/router can route one or more protocols, such as TCP/IP and/or XNS, and bridge all other traffic. |
| bridging | The act of connecting a (typically) high input impedance device in shunt across a transmission line or signal path to monitor or sample a signal. |
| British Standard Wire Gauge | A modification of the Birmingham Wire Gauge and the legal standard of Great Britain for all wires. It is variously known as Standard Wire Gauge (SWG), New British Standard (NBS), English Legal Standard, and Imperial Wire Gauge. |
| brittle temperature | The temperature below which a material becomes brittle, often measured by a cold impact test. |
| broadband | Data transmission at a high rate, generally greater than T1 speeds (1.5 Mbps). This allows the transmission of voice, data and video signals over a single medium. |
| broadband EMI | Interference generated over a wide range of frequencies. For example, automotive ignition noise. |
| broadband signal | A signal transmitted by being impressed on a higher frequency carrier wave. |
| brush | A conductor, usually composed in part of some form of the element carbon, serving to maintain an electrical connection between stationary and moving parts of a motor or apparatus. |
| BSP | broadband service provider |
| BTS | Base transceiver station, or cellular base station for a wireless telephone system. |
| bubble | A raised protrusion of nonconductive film with a contact printed on the underside to provide, in most cases, tactile feel. |
| bubble memory | A serialaccess memory offering very dense storage. Bits are stored as tiny, movable magnetic domains that are circulated through a thin film of magnetic garnet crystal fabricated similar to an IC. Packaging is similar to a DIP. |
| buck boost converter | Also called a "flyback" converter, this topology typically uses a single transistor switch and eliminates the need for an output inductor. Energy is stored in the transformer primary during the first half of the switching period when the transistor switch is on. During the second half or "flyback" period when the transistor is off, this energy is tranferred the transformer secondary and load. Also see Boost Regulator, Buck Regulator, Bridge Converter, Forward Converter, Push-Pull Converter and Resonant Converter. |
| buck derived converter | Also called a "foward" converter, this topology, like the flyback converter, typically uses a single transistor switch. Unlike the flyback converter, energy is tranferred to the transformer secondary while the transistor switch is "on", and stoed in a output inductor. See Boost Regulator, Buck Regulator, Bridge Converter, Flyback Converter, Push Pull Converter and Resonant Converter. |
| buck regulator | A basic DC-DC switching converter topology that takes an unregulated input voltage and produces a lower regulated output voltage. The lower output voltage is achieved by chopping the input voltage with a series connected switch (transistor) which applies pulses to an averaging inductor and capacitor. |
| buffer | (1) A protective layer over the fiber, such as a coating, an inner jacket, or a hard tube. (2) A device which stores information temporarily during data transfers. Often used to isolate one part of a circuit from another. |
| buffer coating | A protective layer, such as an acrylic polymer, applied over the fiber cladding for protective purposes. |
| buffer tube | A hard plastic tube, having an inside diameter several times that of a fiber, that holds one or more fibers. |
| bulk storage memory | Any nonprogrammable large memory. |
| bulkhead | A term used to define a mounting style of connectors. Bulkhead connectors are designed to be inserted into a panel cutout from the rear (component side) of the panel. |
| buna rubber | See Nitrile-Butadiene Rubber and Styrene-Butadiene Rubber. |
| bunch stranding | A method of twisting individual strands to form a finished stranded conductor. Specifically, a number of strands twisted together in a common direction and with a uniform pitch (or twist) per inch. |
| burn in | Operation of a circuit or equipment to stabilize all components and reduce failure rates. |
| burnout | The failure mode in a device that is induced by excessive power dissipation in the device. |
| bus | (1) One or more conductor paths used to transmit information from any of several sources to any of several destinations. (2) - Uninsulated conductor (wire, bar, etc); may be solid or hollow, round or rectangular. Sometimes used to indicate bus bar. |
| bus bar | A heavy bar or strap (usually of copper) for carrying heavy currents, or serving as a common connection between several circuits. |
| bus network | A network topology in which nodes are all connected to a single line serving as the bus. |
| bus reactor | A current limiting reactor connected between two buses, or between two sections of one bus, to limit and localize any disturbance caused by either bus (or bus section). |
| bus-powered | Class of devices that derive their power from the main Hub. Examples include USB hubs, keyboards, mice, internet cameras. |
| butt | When two conductors are placed together end-to-end with their axes in line, but not overlapping. |
| butt gap | A gap, mostly found in E cores, that is obtained by equally spacing all mating surfaces of the core, usually by plastic shims or some other non-magnetic material. This is an alternative to center post gapping, where only the center leg of a core is gapped. To achieve the same gap electrically a center leg gap must be twice as much as a butt gap. |
| butt splice | A splice wherein two wires from opposite ends butt against each other, or against a stop, in the center of the splice. |
| bypass filter | A filter or capacitor that provides a lowimpedance path for high frequencies around a circuit element such as an integrated circuit. |
| byte | A unit of eight (8) bits. |
This list is temporary. The list will not be viewable on another computer and will be deleted within 30 days.
If your browser cookies are cleared, your temporary list will be lost. You can save this list and get all of the My Part List features by becoming a registered user of the Tyco Electronics web site.
If your browser cookies are cleared, your temporary list will be lost. You can save this list and get all of the My Part List features by becoming a registered user of the Tyco Electronics web site.
