Jabil Inc. is an American multinational manufacturing company involved in the design, engineering, and manufacturing of electronic circuit board assemblies and systems, along with supply chain services, primarily serving original equipment manufacturers . It is headquartered in the Gateway area of St. Petersburg, Florida . It is one of the largest companies in the Tampa Bay area .
108-487: Founded in 1966 in the Detroit area, Jabil initially focused on circuit board assembly production and repair for Control Data Systems. The company name, Jabil, derives from the combination of the first names of its founders, James Golden and Bill Morean. After Golden exited the business, Bill Morean's son, William, joined the company and gradually began to shape its direction by signing new contracts, including an offer to purchase
216-507: A majority stake in the company. In 1979, Jabil established a high-volume manufacturing partnership with General Motors (GM), moving towards automated manufacturing and advanced assembly technology. In 1981, Jabil introduced independent test engineering and development services. A year later, the company started volume production of circuit boards with manual surface-mount technology (SMT) processes. By 1984, Jabil had implemented computer-aided design services for production. A year later,
324-602: A PCB had holes drilled for each wire of each component. The component leads were then inserted through the holes and soldered to the copper PCB traces. This method of assembly is called through-hole construction . In 1949, Moe Abramson and Stanislaus F. Danko of the United States Army Signal Corps developed the Auto-Sembly process in which component leads were inserted into a copper foil interconnection pattern and dip soldered . The patent they obtained in 1956
432-426: A PCB may have a coating that protects the copper from corrosion and reduces the chances of solder shorts between traces or undesired electrical contact with stray bare wires. For its function in helping to prevent solder shorts, the coating is called solder resist or solder mask . The pattern to be etched into each copper layer of a PCB is called the "artwork". The etching is usually done using photoresist which
540-504: A brass or lead-coated iron sheet tube, with a crimped seam. The enclosure could also be used as a return conductor. Kuhlo wire could be run exposed on surfaces and painted, or embedded in plaster. Special outlet and junction boxes were made for lamps and switches, made either of porcelain or sheet steel. The crimped seam was not considered as watertight as the Stannos wire used in England, which had
648-453: A building's wiring system are subject to voltage, current, and functional specifications. Wiring safety codes vary by locality, country, or region. The International Electrotechnical Commission (IEC) is attempting to harmonise wiring standards among member countries, but significant variations in design and installation requirements still exist. Materials for wiring interior electrical systems in buildings vary depending on: Wiring systems in
756-514: A cable is permitted to carry. Because multiple conductors bundled in a cable cannot dissipate heat as easily as single insulated conductors, those circuits are always rated at a lower ampacity . Tables in electrical safety codes give the maximum allowable current based on size of conductor, voltage potential, insulation type and thickness, and the temperature rating of the cable itself. The allowable current will also be different for wet or dry locations, for hot (attic) or cool (underground) locations. In
864-563: A communication network service provider based in Texas. In February 2013, Jabil acquired Nypro for $ 665 million in cash. The purchase was completed in July 2013. In 2015, Jabil acquired Shemer Group, an Israeli metal fabrication company specializing in contract manufacturing for high-tech capital equipment manufacturers. In the same year, the company acquired Plasticos Castella, a Spain-based food and consumer packaging manufacturer. In 2018, Jabil acquired
972-410: A copper tube and the space filled with magnesium oxide powder. The whole assembly is drawn down to smaller sizes, thereby compressing the powder. Such cables have a certified fire resistance rating and are more costly than non–fire-rated cable. They have little flexibility and behave more like rigid conduit rather than flexible cables. The environment of the installed wires determine how much current
1080-460: A flat, narrow part of the copper foil that remains after etching. Its resistance , determined by its width, thickness, and length, must be sufficiently low for the current the conductor will carry. Power and ground traces may need to be wider than signal traces . In a multi-layer board one entire layer may be mostly solid copper to act as a ground plane for shielding and power return. For microwave circuits, transmission lines can be laid out in
1188-662: A flexible plastic jacket. In North America and the UK this conductor is usually bare wire but in the UK it is required that this bare Protective Earth (PE) conductor be sheathed in Green/Yellow insulating tubing where the Cable Sheathing has been removed. Most other jurisdictions now require the Protective Earth conductor to be insulated to the same standard as the current carrying conductors with Green/Yellow insulation. With some cables
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#17328766728741296-418: A general estimate of the board complexity. Using more layers allow for more routing options and better control of signal integrity, but are also time-consuming and costly to manufacture. Likewise, selection of the vias for the board also allow fine tuning of the board size, escaping of signals off complex ICs, routing, and long term reliability, but are tightly coupled with production complexity and cost. One of
1404-412: A grounded barrier from the adjacent phases (segregated bus). For conducting large currents between devices, a cable bus is used. For very large currents in generating stations or substations, where it is difficult to provide circuit protection, an isolated-phase bus is used. Each phase of the circuit is run in a separate grounded metal enclosure. The only fault possible is a phase-to-ground fault, since
1512-783: A liquid ink that contains electronic functionalities. HDI (High Density Interconnect) technology allows for a denser design on the PCB and thus potentially smaller PCBs with more traces and components in a given area. As a result, the paths between components can be shorter. HDIs use blind/buried vias, or a combination that includes microvias. With multi-layer HDI PCBs the interconnection of several vias stacked on top of each other (stacked vías, instead of one deep buried via) can be made stronger, thus enhancing reliability in all conditions. The most common applications for HDI technology are computer and mobile phone components as well as medical equipment and military communication equipment. A 4-layer HDI microvia PCB
1620-642: A new 120,000-square-foot building in St. Petersburg. In 2001, Jabil was added to the S&;P 500 Index . In 2013, William D. Morean retired and was succeeded by Timothy Main as board chairman. Later, William E. Peters was named president and Mark Mondello was appointed CEO. In 2014, Jabil was moved from the S&P 500 Index to the S&P MidCap 400 Index . In 2017, Jabil announced that it would be closing its first European international plant in Livingston, United Kingdom, by
1728-583: A non-conductive substrate. Electrical components may be fixed to conductive pads on the outer layers, generally by means of soldering , which both electrically connects and mechanically fastens the components to the board. Another manufacturing process adds vias , drilled holes that allow electrical interconnections between conductive layers. Printed circuit boards are used in nearly all electronic products. Alternatives to PCBs include wire wrap and point-to-point construction , both once popular but now rarely used. PCBs require additional design effort to lay out
1836-446: A planar form such as stripline or microstrip with carefully controlled dimensions to assure a consistent impedance . In radio-frequency and fast switching circuits the inductance and capacitance of the printed circuit board conductors become significant circuit elements, usually undesired; conversely, they can be used as a deliberate part of the circuit design, as in distributed-element filters , antennae , and fuses , obviating
1944-591: A print-and- etch method in the UK, and in the United States Max Schoop obtained a patent to flame-spray metal onto a board through a patterned mask. Charles Ducas in 1925 patented a method of electroplating circuit patterns. Predating the printed circuit invention, and similar in spirit, was John Sargrove 's 1936–1947 Electronic Circuit Making Equipment (ECME) that sprayed metal onto a Bakelite plastic board. The ECME could produce three radio boards per minute. The Austrian engineer Paul Eisler invented
2052-595: A proposal which met the requirements: a ceramic plate would be screenprinted with metallic paint for conductors and carbon material for resistors , with ceramic disc capacitors and subminiature vacuum tubes soldered in place. The technique proved viable, and the resulting patent on the process, which was classified by the U.S. Army, was assigned to Globe Union. It was not until 1984 that the Institute of Electrical and Electronics Engineers (IEEE) awarded Harry W. Rubinstein its Cledo Brunetti Award for early key contributions to
2160-434: A quantifiable impact upon the ampacity derating, because the thermal insulation properties needed for fire resistance also inhibit air cooling of power conductors. Cable trays are used in industrial areas where many insulated cables are run together. Individual cables can exit the tray at any point, simplifying the wiring installation and reducing the labour cost for installing new cables. Power cables may have fittings in
2268-490: A run of cable through several areas, the part with the lowest rating becomes the rating of the overall run. Cables usually are secured with special fittings where they enter electrical apparatus; this may be a simple screw clamp for jacketed cables in a dry location, or a polymer-gasketed cable connector that mechanically engages the armour of an armoured cable and provides a water-resistant connection. Special cable fittings may be applied to prevent explosive gases from flowing in
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#17328766728742376-672: A single family home or duplex, for example, are simple, with relatively low power requirements, infrequent changes to the building structure and layout, usually with dry, moderate temperature and non-corrosive environmental conditions. In a light commercial environment, more frequent wiring changes can be expected, large apparatus may be installed and special conditions of heat or moisture may apply. Heavy industries have more demanding wiring requirements, such as very large currents and higher voltages, frequent changes of equipment layout, corrosive, or wet or explosive atmospheres. In facilities that handle flammable gases or liquids, special rules may govern
2484-482: A soldered sheath. A somewhat similar system called "concentric wiring" was introduced in the United States around 1905. In this system, an insulated electrical wire was wrapped with copper tape which was then soldered, forming the grounded (return) conductor of the wiring system. The bare metal sheath, at earth potential, was considered safe to touch. While companies such as General Electric manufactured fittings for
2592-440: Is cotton paper impregnated with phenolic resin , often tan or brown. When a PCB has no components installed, it is less ambiguously called a printed wiring board ( PWB ) or etched wiring board . However, the term "printed wiring board" has fallen into disuse. A PCB populated with electronic components is called a printed circuit assembly ( PCA ), printed circuit board assembly or PCB assembly ( PCBA ). In informal usage,
2700-451: Is fire retardant , the dielectric constant (e r ), the loss tangent (tan δ), the tensile strength , the shear strength , the glass transition temperature (T g ), and the Z-axis expansion coefficient (how much the thickness changes with temperature). There are quite a few different dielectrics that can be chosen to provide different insulating values depending on the requirements of
2808-437: Is a common engineering error in high-frequency digital design; it increases the cost of the boards without a corresponding benefit. Signal degradation by loss tangent and dielectric constant can be easily assessed by an eye pattern . Moisture absorption occurs when the material is exposed to high humidity or water. Both the resin and the reinforcement may absorb water; water also may be soaked by capillary forces through voids in
2916-402: Is a medium used to connect or "wire" components to one another in a circuit . It takes the form of a laminated sandwich structure of conductive and insulating layers: each of the conductive layers is designed with a pattern of traces, planes and other features (similar to wires on a flat surface) etched from one or more sheet layers of copper laminated onto or between sheet layers of
3024-477: Is about 73, compared to about 4 for common circuit board materials. Absorbed moisture can also vaporize on heating, as during soldering , and cause cracking and delamination , the same effect responsible for "popcorning" damage on wet packaging of electronic parts. Careful baking of the substrates may be required to dry them prior to soldering. Often encountered materials: Less-often encountered materials: Copper thickness of PCBs can be specified directly or as
3132-494: Is accomplished through the use of thicker, specially constructed jackets, and by tinning the individual wire stands. In North American practice, for residential and light commercial buildings fed with a single-phase split 120/240 service , an overhead cable from a transformer on a power pole is run to the service entrance point. The cable is a three conductor twisted "triplex" cable with a bare neutral and two insulated conductors, with no overall cable jacket. The neutral conductor
3240-579: Is an electrical installation of cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure. Wiring is subject to safety standards for design and installation. Allowable wire and cable types and sizes are specified according to the circuit operating voltage and electric current capability, with further restrictions on the environmental conditions, such as ambient temperature range, moisture levels, and exposure to sunlight and chemicals. Associated circuit protection, control, and distribution devices within
3348-468: Is an important consideration especially with ball grid array (BGA) and naked die technologies, and glass fiber offers the best dimensional stability. FR-4 is by far the most common material used today. The board stock with unetched copper on it is called "copper-clad laminate". With decreasing size of board features and increasing frequencies, small nonhomogeneities like uneven distribution of fiberglass or other filler, thickness variations, and bubbles in
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3456-451: Is coated onto the PCB, then exposed to light projected in the pattern of the artwork. The resist material protects the copper from dissolution into the etching solution. The etched board is then cleaned. A PCB design can be mass-reproduced in a way similar to the way photographs can be mass-duplicated from film negatives using a photographic printer . FR-4 glass epoxy is the most common insulating substrate. Another substrate material
3564-418: Is equivalent in quality to an 8-layer through-hole PCB, so HDI technology can reduce costs. HDI PCBs are often made using build-up film such as ajinomoto build-up film, which is also used in the production of flip chip packages. Some PCBs have optical waveguides, similar to optical fibers built on the PCB. A basic PCB consists of a flat sheet of insulating material and a layer of copper foil , laminated to
3672-632: Is estimated to reach $ 79 billion by 2024. Before the development of printed circuit boards, electrical and electronic circuits were wired point-to-point on a chassis. Typically, the chassis was a sheet metal frame or pan, sometimes with a wooden bottom. Components were attached to the chassis, usually by insulators when the connecting point on the chassis was metal, and then their leads were connected directly or with jumper wires by soldering , or sometimes using crimp connectors, wire connector lugs on screw terminals, or other methods. Circuits were large, bulky, heavy, and relatively fragile (even discounting
3780-496: Is often a supporting "messenger" steel wire, which is used to support the insulated line conductors. Electrical devices often use copper conductors because of their properties, including their high electrical conductivity , tensile strength , ductility , creep resistance, corrosion resistance , thermal conductivity , coefficient of thermal expansion , solderability , resistance to electrical overloads , compatibility with electrical insulators , and ease of installation. Copper
3888-489: Is permitted, unless the fitting is rated or listed for multiple cables. Special cable constructions and termination techniques are required for cables installed in ships. Such assemblies are subjected to environmental and mechanical extremes. Therefore, in addition to electrical and fire safety concerns, such cables may also be required to be pressure-resistant where they penetrate a vessel's bulkheads. They must also resist corrosion caused by salt water or salt spray , which
3996-799: Is solid wire, since the wiring is not required to be very flexible. Building wire conductors larger than 10 AWG (or about 5 mm ) are stranded for flexibility during installation, but are not sufficiently pliable to use as appliance cord. Cables for industrial, commercial and apartment buildings may contain many insulated conductors in an overall jacket, with helical tape steel or aluminium armour, or steel wire armour, and perhaps as well an overall PVC or lead jacket for protection from moisture and physical damage. Cables intended for very flexible service or in marine applications may be protected by woven bronze wires. Power or communications cables (e.g., computer networking) that are routed in or through air-handling spaces (plenums) of office buildings are required under
4104-453: Is specified in units of ounces per square foot (oz/ft ), commonly referred to simply as ounce . Common thicknesses are 1/2 oz/ft (150 g/m ), 1 oz/ft (300 g/m ), 2 oz/ft (600 g/m ), and 3 oz/ft (900 g/m ). These work out to thicknesses of 17.05 μm (0.67 thou ), 34.1 μm (1.34 thou ), 68.2 μm (2.68 thou), and 102.3 μm (4.02 thou), respectively. Wiring Electrical wiring
4212-468: Is the most common thickness; 2 oz (70 μm) and 0.5 oz (17.5 μm) thickness is often an option. Less common are 12 and 105 μm, 9 μm is sometimes available on some substrates. Flexible substrates typically have thinner metalization. Metal-core boards for high power devices commonly use thicker copper; 35 μm is usual but also 140 and 400 μm can be encountered. In the US, copper foil thickness
4320-455: Is used in industrial cables and power cables installed underground because of its superior moisture resistance. Insulated cables are rated by their allowable operating voltage and their maximum operating temperature at the conductor surface. A cable may carry multiple usage ratings for applications, for example, one rating for dry installations and another when exposed to moisture or oil. Generally, single conductor building wire in small sizes
4428-569: Is used in many types of electrical wiring. Aluminium wire was common in North American residential wiring from the late 1960s to mid-1970s due to the rising cost of copper. Because of its greater resistivity , aluminium wiring requires larger conductors than copper. For instance, instead of 14 AWG ( American wire gauge ) copper wire, aluminium wiring would need to be 12 AWG on a typical 15 ampere lighting circuit, though local building codes vary. Solid aluminium conductors were originally made in
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4536-427: Is used to distribute power down the length of a building; it is constructed to allow tap-off switches or motor controllers to be installed at designated places along the bus. The big advantage of this scheme is the ability to remove or add a branch circuit without removing voltage from the whole duct. Bus ducts may have all phase conductors in the same enclosure (non-isolated bus), or may have each conductor separated by
4644-485: The CO/ALR "copper-aluminium-revised" designation) were developed to reduce these problems. While larger sizes are still used to feed power to electrical panels and large devices, aluminium wiring for residential use has acquired a poor reputation and has fallen out of favour. Aluminium conductors are still heavily used for bulk power transmission , power distribution , and large feeder circuits with heavy current loads, due to
4752-449: The glass transition temperature the resin in the composite softens and significantly increases thermal expansion; exceeding T g then exerts mechanical overload on the board components - e.g. the joints and the vias. Below T g the thermal expansion of the resin roughly matches copper and glass, above it gets significantly higher. As the reinforcement and copper confine the board along the plane, virtually all volume expansion projects to
4860-399: The signal propagation speed , frequency dependence introduces phase distortion in wideband applications; as flat a dielectric constant vs frequency characteristics as is achievable is important here. The impedance of transmission lines decreases with frequency, therefore faster edges of signals reflect more than slower ones. Dielectric breakdown voltage determines the maximum voltage gradient
4968-525: The 1930s, was knob and tube (K&T) wiring: single conductors were run through cavities between the structural members in walls and ceilings, with ceramic tubes forming protective channels through joists and ceramic knobs attached to the structural members to provide air between the wire and the lumber and to support the wires. Since air was free to circulate over the wires, smaller conductors could be used than required in cables. By arranging wires on opposite sides of building structural members, some protection
5076-457: The 1960s from a utility-grade aluminium alloy that had undesirable properties for a building wire, and were used with wiring devices intended for copper conductors. These practices were found to cause defective connections and fire hazards. In the early 1970s new aluminium wire made from one of several special alloys was introduced, and all devices – breakers, switches, receptacles, splice connectors , wire nuts , etc. — were specially designed for
5184-558: The PCB surface, instead of wire leads to pass through holes. Components became much smaller and component placement on both sides of the board became more common than with through-hole mounting, allowing much smaller PCB assemblies with much higher circuit densities. Surface mounting lends itself well to a high degree of automation, reducing labor costs and greatly increasing production rates compared with through-hole circuit boards. Components can be supplied mounted on carrier tapes. Surface mount components can be about one-quarter to one-tenth of
5292-471: The S&;P 500 index. On 19 April 2024, Jabil announced that CEO Kenny Wilson would take paid leave pending an investigation related to company policies, although not affecting the company's financial statements or reporting. Following Wilson's leave, which began on April 15, CFO Michael Dastoor was appointed as interim CEO by the board of directors. Following the completion of the investigation, Wilson resigned from
5400-453: The back of the board in opposite directions to improve the part's mechanical strength), soldering the leads, and trimming off the ends. Leads may be soldered either manually or by a wave soldering machine. Surface-mount technology emerged in the 1960s, gained momentum in the early 1980s, and became widely used by the mid-1990s. Components were mechanically redesigned to have small metal tabs or end caps that could be soldered directly onto
5508-423: The benefit of air cooling. A variation is to use heavy cables, especially where it is desirable to transpose or "roll" phases. In industrial applications, conductor bars are often pre-assembled with insulators in grounded enclosures. This assembly, known as bus duct or busway, can be used for connections to large switchgear or for bringing the main power feed into a building. A form of bus duct known as "plug-in bus"
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#17328766728745616-437: The board and soldered onto copper traces on the other side. Boards may be single-sided, with an unplated component side, or more compact double-sided boards, with components soldered on both sides. Horizontal installation of through-hole parts with two axial leads (such as resistors, capacitors, and diodes) is done by bending the leads 90 degrees in the same direction, inserting the part in the board (often bending leads located on
5724-519: The breakable glass envelopes of the vacuum tubes that were often included in the circuits), and production was labor-intensive, so the products were expensive. Development of the methods used in modern printed circuit boards started early in the 20th century. In 1903, a German inventor, Albert Hanson, described flat foil conductors laminated to an insulating board, in multiple layers. Thomas Edison experimented with chemical methods of plating conductors onto linen paper in 1904. Arthur Berry in 1913 patented
5832-512: The ceramic substrate. In 1948, the US released the invention for commercial use. Printed circuits did not become commonplace in consumer electronics until the mid-1950s, after the Auto-Sembly process was developed by the United States Army. At around the same time in the UK work along similar lines was carried out by Geoffrey Dummer , then at the RRDE . Motorola was an early leader in bringing
5940-757: The circuit, but manufacturing and assembly can be automated. Electronic design automation software is available to do much of the work of layout. Mass-producing circuits with PCBs is cheaper and faster than with other wiring methods, as components are mounted and wired in one operation. Large numbers of PCBs can be fabricated at the same time, and the layout has to be done only once. PCBs can also be made manually in small quantities, with reduced benefits. PCBs can be single-sided (one copper layer), double-sided (two copper layers on both sides of one substrate layer), or multi-layer (outer and inner layers of copper, alternating with layers of substrate). Multi-layer PCBs allow for much higher component density, because circuit traces on
6048-539: The circuit. Some of these dielectrics are polytetrafluoroethylene (Teflon), FR-4, FR-1, CEM-1 or CEM-3. Well known pre-preg materials used in the PCB industry are FR-2 (phenolic cotton paper), FR-3 (cotton paper and epoxy), FR-4 (woven glass and epoxy), FR-5 (woven glass and epoxy), FR-6 (matte glass and polyester), G-10 (woven glass and epoxy), CEM-1 (cotton paper and epoxy), CEM-2 (cotton paper and epoxy), CEM-3 (non-woven glass and epoxy), CEM-4 (woven glass and epoxy), CEM-5 (woven glass and polyester). Thermal expansion
6156-467: The company acquired a factory of Lucent Technologies in Shanghai. In 2002, the company also acquired contract manufacturing services of Philips. In 2005, Jabil acquired Varian's electronics manufacturing business for $ 195 million. A year later, Jabil expanded its operations to Taiwan and acquired Green Point for $ 881 million through its subsidiary Jabil Circuit Taiwan. In 2011, Jabil acquired Telmar Network,
6264-586: The company and Dastoor was named CEO. Jabil has acquired numerous companies and arms of companies. Their acquisitions have expanded their presence in countries such as China, Mexico, India, Spain, the Netherlands and Russia. In 1999, Jabil began its operations in China by acquiring GET Manufacturing. In 2001, Jabil expanded its manufacturing capability and acquired Intel's manufacturing facility in Malaysia. A year later,
6372-549: The company transitioned to highly automated volume production using SMT processes. Towards the end of the 1980s, Jabil adopted the automated tape-automated bonding (TAB) process for circuit board production. In 1982, Jabil moved its headquarters from Detroit to St. Petersburg, Florida . In April 1993, Jabil became a publicly traded company, listing its shares on the New York Stock Exchange . In 1997, Jabil expanded its manufacturing capacity and workforce, completing
6480-431: The components, test points , or identifying text. Originally, silkscreen printing was used for this purpose, but today other, finer quality printing methods are usually used. Normally the legend does not affect the function of a PCBA. A printed circuit board can have multiple layers of copper which almost always are arranged in pairs. The number of layers and the interconnection designed between them (vias, PTHs) provide
6588-455: The conductors. Rubber insulation further inside the cable often is in better condition than the insulation exposed at connections, due to reduced exposure to oxygen. The sulfur in vulcanized rubber insulation attacked bare copper wire so the conductors were tinned to prevent this. The conductors reverted to being bare when rubber ceased to be used. About 1950, PVC insulation and jackets were introduced, especially for residential wiring. About
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#17328766728746696-685: The contact surface does not oxidise. Insulated wires may be run in one of several forms between electrical devices. This may be a specialised bendable pipe, called a conduit , or one of several varieties of metal (rigid steel or aluminium) or non-metallic ( PVC or HDPE ) tubing. Rectangular cross-section metal or PVC wire troughs (North America) or trunking (UK) may be used if many circuits are required. Wires run underground may be run in plastic tubing encased in concrete, but metal elbows may be used in severe pulls. Wiring in exposed areas, for example factory floors, may be run in cable trays or rectangular raceways having lids. Where wiring, or raceways that hold
6804-675: The current capacity (ampacity). Special sealed fittings are used for wiring routed through potentially explosive atmospheres. For very high currents in electrical apparatus, and for high currents distributed through a building, bus bars can be used. (The term "bus" is a contraction of the Latin omnibus – meaning "for all".) Each live ("hot") conductor of such a system is a rigid piece of copper or aluminium, usually in flat bars (but sometimes as tubing or other shapes). Open bus bars are never used in publicly accessible areas, although they are used in manufacturing plants and power company switch yards to gain
6912-464: The desired final thickness and dielectric characteristics. Available standard laminate thickness are listed in ANSI/IPC-D-275. The cloth or fiber material used, resin material, and the cloth to resin ratio determine the laminate's type designation (FR-4, CEM -1, G-10 , etc.) and therefore the characteristics of the laminate produced. Important characteristics are the level to which the laminate
7020-492: The development of printed components and conductors on a common insulating substrate. Rubinstein was honored in 1984 by his alma mater, the University of Wisconsin-Madison , for his innovations in the technology of printed electronic circuits and the fabrication of capacitors. This invention also represents a step in the development of integrated circuit technology, as not only wiring but also passive components were fabricated on
7128-403: The dielectric constant). The reinforcement type defines two major classes of materials: woven and non-woven. Woven reinforcements are cheaper, but the high dielectric constant of glass may not be favorable for many higher-frequency applications. The spatially nonhomogeneous structure also introduces local variations in electrical parameters, due to different resin/glass ratio at different areas of
7236-458: The enclosures are separated. This type of bus can be rated up to 50,000 amperes and up to hundreds of kilovolts (during normal service, not just for faults), but is not used for building wiring in the conventional sense. Electrical panels are easily accessible junction boxes used to reroute and switch electrical services . The term is often used to refer to circuit breaker panels or fuseboxes. Local codes can specify physical clearance around
7344-609: The end of the year. Two hundred sixty-six employees in Livingston would lose their jobs. Jabil laid off approximately 400 people in September 2016, 100 of those being corporate employees located in St. Petersburg Florida. In March 2024, the company announced it would lay off 120 workers in Vancouver , Washington . In January 2023, it was reported that Jabil had started manufacturing components for AirPods in India. In December 2023, Jabil rejoined
7452-405: The finished multilayer board) are plated-through, before the layers are laminated together. Only the outer layers need be coated; the inner copper layers are protected by the adjacent substrate layers. "Through hole" components are mounted by their wire leads passing through the board and soldered to traces on the other side. "Surface mount" components are attached by their leads to copper traces on
7560-437: The framing of the building or on running boards. Where conductors went through walls, they were protected with cloth tape. Splices were done similarly to telegraph connections, and soldered for security. Underground conductors were insulated with wrappings of cloth tape soaked in pitch, and laid in wooden troughs which were then buried. Such wiring systems were unsatisfactory because of the danger of electrocution and fire, plus
7668-510: The high labour cost for such installations. The first electrical codes arose in the 1880s with the commercial introduction of electrical power; however, many conflicting standards existed for the selection of wire sizes and other design rules for electrical installations, and a need was seen to introduce uniformity on the grounds of safety. The earliest standardized method of wiring in buildings, in common use in North America from about 1880 to
7776-514: The individual conductors are wrapped in paper before the plastic jacket is applied. Special versions of non-metallic sheathed cables, such as US Type UF, are designed for direct underground burial (often with separate mechanical protection) or exterior use where exposure to ultraviolet radiation (UV) is a possibility. These cables differ in having a moisture-resistant construction, lacking paper or other absorbent fillers, and being formulated for UV resistance. Rubber-like synthetic polymer insulation
7884-447: The inner layers would otherwise take up surface space between components. The rise in popularity of multilayer PCBs with more than two, and especially with more than four, copper planes was concurrent with the adoption of surface mount technology . However, multilayer PCBs make repair, analysis, and field modification of circuits much more difficult and usually impractical. The world market for bare PCBs exceeded $ 60.2 billion in 2014 and
7992-406: The installation and wiring of electrical equipment in hazardous areas . Wires and cables are rated by the circuit voltage, temperature rating and environmental conditions (moisture, sunlight, oil, chemicals) in which they can be used. A wire or cable has a voltage (to neutral) rating and a maximum conductor surface temperature rating. The amount of current a cable or wire can safely carry depends on
8100-651: The installation conditions. The international standard wire sizes are given in the IEC 60228 standard of the International Electrotechnical Commission . In North America, the American Wire Gauge standard for wire sizes is used. Modern non-metallic sheathed cables, such as (US and Canadian) Types NMB and NMC, consist of two to four wires covered with thermoplastic insulation, plus a wire for Protective Earthing/Grounding (bonding), surrounded by
8208-471: The insulation, with an overall woven jacket, usually impregnated with tar as a protection from moisture. Waxed paper was used as a filler and separator. Over time, rubber-insulated cables become brittle because of exposure to atmospheric oxygen, so they must be handled with care and are usually replaced during renovations. When switches, socket outlets or light fixtures are replaced, the mere act of tightening connections may cause hardened insulation to flake off
8316-419: The interior of jacketed cables, where the cable passes through areas where flammable gases are present. To prevent loosening of the connections of individual conductors of a cable, cables must be supported near their entrance to devices and at regular intervals along their runs. In tall buildings, special designs are required to support the conductors of vertical runs of cable. Generally, only one cable per fitting
8424-427: The internal layers is used as ground plane or power plane, to achieve better signal integrity, higher signaling frequencies, lower EMI, and better power supply decoupling. In multi-layer boards, the layers of material are laminated together in an alternating sandwich: copper, substrate, copper, substrate, copper, etc.; each plane of copper is etched, and any internal vias (that will not extend to both outer surfaces of
8532-498: The material can be subjected to before suffering a breakdown (conduction, or arcing, through the dielectric). Tracking resistance determines how the material resists high voltage electrical discharges creeping over the board surface. Loss tangent determines how much of the electromagnetic energy from the signals in the conductors is absorbed in the board material. This factor is important for high frequencies. Low-loss materials are more expensive. Choosing unnecessarily low-loss material
8640-491: The materials and along the reinforcement. Epoxies of the FR-4 materials are not too susceptible, with absorption of only 0.15%. Teflon has very low absorption of 0.01%. Polyimides and cyanate esters, on the other side, suffer from high water absorption. Absorbed water can lead to significant degradation of key parameters; it impairs tracking resistance, breakdown voltage, and dielectric parameters. Relative dielectric constant of water
8748-466: The medical devices business of Johnson & Johnson . In 2021, Jabil acquired Ecologic Brands. In August 2023, Jabil sold its mobility business in China to BYD . In November 2023, Jabil acquired the Silicon Photonics business of Intel. In November 2023, Jabil acquired ProcureAbility. Circuit board A printed circuit board ( PCB ), also called printed wiring board ( PWB ),
8856-404: The model building code to be either encased in metal conduit, or rated for low flame and smoke production. For some industrial uses in steel mills and similar hot environments, no organic material gives satisfactory service. Cables insulated with compressed mica flakes are sometimes used. Another form of high-temperature cable is mineral-insulated cable , with individual conductors placed within
8964-498: The need for additional discrete components. High density interconnects (HDI) PCBs have tracks or vias with a width or diameter of under 152 micrometers. Laminates are manufactured by curing layers of cloth or paper with thermoset resin under pressure and heat to form an integral final piece of uniform thickness. They can be up to 4 by 8 feet (1.2 by 2.4 m) in width and length. Varying cloth weaves (threads per inch or cm), cloth thickness, and resin percentage are used to achieve
9072-434: The panels. Squirrels , rats, and other rodents may gnaw on unprotected wiring, causing fire and shock hazards. This is especially true of PVC-insulated telephone and computer network cables. Several techniques have been developed to deter these pests, including insulation loaded with pepper dust. The first interior power wiring systems used conductors that were bare or covered with cloth, which were secured by staples to
9180-471: The point-to-point chassis construction method remained in common use in industry (such as TV and hi-fi sets) into at least the late 1960s. Printed circuit boards were introduced to reduce the size, weight, and cost of parts of the circuitry. In 1960, a small consumer radio receiver might be built with all its circuitry on one circuit board, but a TV set would probably contain one or more circuit boards. Originally, every electronic component had wire leads , and
9288-573: The printed circuit as part of a radio set while working in the UK around 1936. In 1941 a multi-layer printed circuit was used in German magnetic influence naval mines . Around 1943 the United States began to use the technology on a large scale to make proximity fuzes for use in World War II. Such fuzes required an electronic circuit that could withstand being fired from a gun, and could be produced in quantity. The Centralab Division of Globe Union submitted
9396-474: The process into consumer electronics, announcing in August 1952 the adoption of "plated circuits" in home radios after six years of research and a $ 1M investment. Motorola soon began using its trademarked term for the process, PLAcir, in its consumer radio advertisements. Hallicrafters released its first "foto-etch" printed circuit product, a clock-radio, on November 1, 1952. Even as circuit boards became available,
9504-403: The protruding wires are cut off and discarded. From the 1980s onward, small surface mount parts have been used increasingly instead of through-hole components; this has led to smaller boards for a given functionality and lower production costs, but with some additional difficulty in servicing faulty boards. In the 1990s the use of multilayer surface boards became more frequent. As a result, size
9612-592: The purpose. These newer aluminium wires and special designs address problems with junctions between dissimilar metals, oxidation on metal surfaces, and mechanical effects that occur as different metals expand at different rates with increases in temperature. Unlike copper, aluminium has a tendency to creep or cold-flow under pressure, so older plain steel screw clamped connections could become loose over time. Newer electrical devices designed for aluminium conductors have features intended to compensate for this effect. Unlike copper, aluminium forms an insulating oxide layer on
9720-441: The resin matrix, and the associated local variations in the dielectric constant, are gaining importance. The circuit-board substrates are usually dielectric composite materials. The composites contain a matrix (usually an epoxy resin ) and a reinforcement (usually a woven, sometimes nonwoven, glass fibers, sometimes even paper), and in some cases a filler is added to the resin (e.g. ceramics; titanate ceramics can be used to increase
9828-478: The same side of the board. A board may use both methods for mounting components. PCBs with only through-hole mounted components are now uncommon. Surface mounting is used for transistors , diodes , IC chips , resistors , and capacitors. Through-hole mounting may be used for some large components such as electrolytic capacitors and connectors. The first PCBs used through-hole technology , mounting electronic components by lead inserted through holes on one side of
9936-408: The simplest boards to produce is the two-layer board. It has copper on both sides that are referred to as external layers; multi layer boards sandwich additional internal layers of copper and insulation. After two-layer PCBs, the next step up is the four-layer. The four layer board adds significantly more routing options in the internal layers as compared to the two layer board, and often some portion of
10044-414: The size and weight of through-hole components, and passive components much cheaper. However, prices of semiconductor surface mount devices (SMDs) are determined more by the chip itself than the package, with little price advantage over larger packages, and some wire-ended components, such as 1N4148 small-signal switch diodes, are actually significantly cheaper than SMD equivalents. Each trace consists of
10152-422: The substrate. Chemical etching divides the copper into separate conducting lines called tracks or circuit traces , pads for connections, vias to pass connections between layers of copper, and features such as solid conductive areas for electromagnetic shielding or other purposes. The tracks function as wires fixed in place, and are insulated from each other by air and the board substrate material. The surface of
10260-499: The surface. This is sometimes addressed by coating aluminium conductors with an antioxidant paste (containing zinc dust in a low-residue polybutene base ) at joints, or by applying a mechanical termination designed to break through the oxide layer during installation. Some terminations on wiring devices designed only for copper wire would overheat under heavy current load and cause fires when used with aluminium conductors. Revised standards for wire materials and wiring devices (such as
10368-477: The system and a few buildings were wired with it, it was never adopted into the US National Electrical Code. Drawbacks of the system were that special fittings were required, and that any defect in the connection of the sheath would result in the sheath becoming energised. Armored cables with two rubber-insulated conductors in a flexible metal sheath were used as early as 1906, and were considered at
10476-402: The term "printed circuit board" most commonly means "printed circuit assembly" (with components). The IPC preferred term for an assembled board is circuit card assembly ( CCA ), and for an assembled backplane it is backplane assembly . "Card" is another widely used informal term for a "printed circuit assembly". For example, expansion card . A PCB may be printed with a legend identifying
10584-419: The thickness and stresses the plated-through holes. Repeated soldering or other exposition to higher temperatures can cause failure of the plating, especially with thicker boards; thick boards therefore require a matrix with a high T g . The materials used determine the substrate's dielectric constant . This constant is also dependent on frequency, usually decreasing with frequency. As this constant determines
10692-503: The time a better method than open knob-and-tube wiring, although much more expensive. The first rubber-insulated cables for US building wiring were introduced in 1922 with US patent 1458803 , Burley, Harry & Rooney, Henry, "Insulated electric wire", issued 1923-06-12, assigned to Boston Insulated Wire and Cable . These were two or more solid copper electrical wires with rubber insulation, plus woven cotton cloth over each conductor for protection of
10800-559: The time. Paper-insulated cables proved unsuitable for interior wiring installations because very careful workmanship was required on the lead sheaths to ensure moisture did not affect the insulation. A system later invented in the UK in 1908 employed vulcanised-rubber insulated wire enclosed in a strip metal sheath. The metal sheath was bonded to each metal wiring device to ensure earthing continuity. A system developed in Germany called "Kuhlo wire" used one, two, or three rubber-insulated wires in
10908-656: The tray to maintain clearance between the conductors, but small control wiring is often installed without any intentional spacing between cables. Local electrical regulations may restrict or place special requirements on mixing of voltage levels within one cable tray. Good design practices may segregate, for example, low level measurement or signal cables from trays carrying high power branch circuits, to prevent induction of noise into sensitive circuits. Since wires run in conduits or underground cannot dissipate heat as easily as in open air, and since adjacent circuits contribute induced currents, wiring regulations give rules to establish
11016-510: The various advantages they offer over copper wiring. Aluminium conductors both cost and weigh less than copper conductors, so a much larger cross sectional area can be used for the same weight and price. This can compensate for the higher resistance and lower mechanical strength of aluminium, meaning the larger cross sectional area is needed to achieve comparable current capacity and other features. Aluminium conductors must be installed with compatible connectors and special care must be taken to ensure
11124-511: The weave pattern. Nonwoven reinforcements, or materials with low or no reinforcement, are more expensive but more suitable for some RF/analog applications. The substrates are characterized by several key parameters, chiefly thermomechanical ( glass transition temperature , tensile strength , shear strength , thermal expansion ), electrical ( dielectric constant , loss tangent , dielectric breakdown voltage , leakage current , tracking resistance ...), and others (e.g. moisture absorption ). At
11232-440: The weight of copper per area (in ounce per square foot) which is easier to measure. One ounce per square foot is 1.344 mils or 34 micrometers thickness. Heavy copper is a layer exceeding three ounces of copper per ft , or approximately 0.0042 inches (4.2 mils, 105 μm) thick. Heavy copper layers are used for high current or to help dissipate heat. On the common FR-4 substrates, 1 oz copper per ft (35 μm)
11340-475: The wiring, must traverse fire-resistance rated walls and floors, the openings are required by local building codes to be firestopped . In cases where safety-critical wiring must be kept operational during an accidental fire, fireproofing must be applied to maintain circuit integrity in a manner to comply with a product's certification listing . The nature and thickness of any passive fire protection materials used in conjunction with wiring and raceways has
11448-760: Was afforded against short-circuits that can be caused by driving a nail into both conductors simultaneously. By the 1940s, the labor cost of installing two conductors rather than one cable resulted in a decline in new knob-and-tube installations. However, the US code still allows new K&T wiring installations in special situations (some rural and industrial applications). In the United Kingdom, an early form of insulated cable, introduced in 1896, consisted of two impregnated-paper-insulated conductors in an overall lead sheath. Joints were soldered, and special fittings were used for lamp holders and switches. These cables were similar to underground telegraph and telephone cables of
11556-433: Was assigned to the U.S. Army. With the development of board lamination and etching techniques, this concept evolved into the standard printed circuit board fabrication process in use today. Soldering could be done automatically by passing the board over a ripple, or wave, of molten solder in a wave-soldering machine. However, the wires and holes are inefficient since drilling holes is expensive and consumes drill bits and
11664-426: Was further minimized and both flexible and rigid PCBs were incorporated in different devices. In 1995 PCB manufacturers began using microvia technology to produce High-Density Interconnect (HDI) PCBs. Recent advances in 3D printing have meant that there are several new techniques in PCB creation. 3D printed electronics (PEs) can be utilized to print items layer by layer and subsequently the item can be printed with
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