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Encyclopedia > Printed circuit board
Part of a 1983 Sinclair ZX Spectrum computer board; a populated PCB, showing the conductive traces, vias (the through-hole paths to the other surface), and some mounted electrical components
PCB Layout Program

A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, or traces, etched from copper sheets laminated onto a non-conductive substrate. Alternative names are printed wiring board (PWB),and etched wiring board. A PCB populated with electronic components is a printed circuit assembly (PCA), also known as a printed circuit board assembly (PCBA). Image File history File links PCB_Spectrum. ... Image File history File links PCB_Spectrum. ... Sinclair Research Ltd was a home computer company founded by Clive Sinclair in Cambridge, England. ... The ZX Spectrum is an 8-bit personal home computer released in the United Kingdom in 1982 by Sinclair Research Ltd. ... In printed circuit board design, via refers to a pad with a plated hole that connects copper tracks from one layer of the board to other layer(s). ... Image File history File links Download high-resolution version (1280x1024, 216 KB) Summary Screen Shot of PCB Layout software for creating Printed Circuit Board Licensing This is a screenshot of copyrighted computer software, and the copyright for it is most likely held by the author(s) or the company that... Image File history File links Download high-resolution version (1280x1024, 216 KB) Summary Screen Shot of PCB Layout software for creating Printed Circuit Board Licensing This is a screenshot of copyrighted computer software, and the copyright for it is most likely held by the author(s) or the company that... Various components An electronic component is a basic electronic element usually packaged in a discrete form with two or more connecting leads or metallic pads. ... In science and engineering, conductors are materials that contain movable charges of electricity. ... On a printed circuit board, a signal trace is the printed circuit equivalent of a wire for carrying electrical signals. ... In industry, etching (sometimes called chemical milling or wet etching) is the process of using acids, bases or other chemicals to dissolve away unwanted materials such as metals, semiconductor materials or glass. ... A laminate is a material constructed by uniting two or more layers of material together. ...


PCBs are rugged, inexpensive, and can be highly reliable. They require much more layout effort and higher initial cost than either wire-wrapped or point-to-point constructed circuits, but are much cheaper and faster for high-volume production. Much of the electronics industry's PCB design, assembly, and quality control needs are set by standards that are published by the IPC organization. This article deals with electronics manufacturing and prototyping techniques, see Wire wrap jewellery for the jewellery related topic Wire wrap is a technique for constructing small numbers of complex electronics. ... Point-to-point construction is the way most electronics were constructed before the 1950s. ... IPC, the Association Connecting Electronics Industries (formerly known as the Institute for Interconnecting and Packaging Electronic Circuits), is an organization whose aim is to standardize the assembly and production requirements of electronic equipment and assemblies. ...

Contents

Manufacturing

Materials

Conducting layers are typically made of thin copper foil. Insulating materials have a wider scale: phenolic paper, glass fibre and different plastics (polyeithrothemin) are commonly used. Usually PCB factories use prepregs (short for preimpregnated), which are a combination of glass fibre mat, nonwoven material and resin. Copper foil and prepreg are typically laminated together with epoxy resin. Well known prepreg 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 (Woven glass and epoxy), CEM-4 (Woven glass and epoxy), CEM-5 (Woven glass and polyester). Epoxy or polyepoxide is a thermosetting epoxide polymer that cures when mixed with a catalyzing agent or hardener. Most common epoxy resins are produced from a reaction between Epichorohydrin & Bisphenol A. The first commercial attempts to prepare resins from epichlorohydrin occurred in 1927 in the United States. ... FR-2 is an abbreviation for Flame Resistant 2. ... FR-4, an abbreviation for Flame Retardant 4, is a type of material used for making a printed circuit board (PCB). ...

A PCB as a design on a computer (left) and realized as a board assembly with populated components (right). The board is double sided, with through-hole plating, green solder resist, and white silkscreen printing. Both surface mount and through-hole components have been used.

Image File history File links Size of this preview: 800 × 427 pixelsFull resolution (3000 × 1600 pixel, file size: 2. ... Image File history File links Size of this preview: 800 × 427 pixelsFull resolution (3000 × 1600 pixel, file size: 2. ...

Patterning (etching)

The vast majority of printed circuit boards are made by bonding a layer of copper over the entire substrate, sometimes on both sides, (creating a "blank PCB") then removing unwanted copper after applying a temporary mask (eg. by etching), leaving only the desired copper traces. A few PCBs are made by adding traces to the bare substrate (or a substrate with a very thin layer of copper) usually by a complex process of multiple electroplating steps. Electroplating is the process of using Davd lloyd current to coat an electrically conductive object with a relatively thin layer of metal. ...


There are three common "subtractive" methods (methods that remove copper) used for the production of printed circuit boards:

  1. Silk screen printing uses etch-resistant inks to protect the copper foil. Subsequent etching removes the unwanted copper. Alternatively, the ink may be conductive, printed on a blank (non-conductive) board. The latter technique is also used in the manufacture of hybrid circuits.
  2. Photoengraving uses a photomask and chemical etching to remove the copper foil from the substrate. The photomask is usually prepared with a photoplotter from data produced by a technician using CAM, or computer-aided manufacturing software. Laser-printed transparencies are typically employed for phototools; however, direct laser imaging techniques are being employed to replace phototools for high-resolution requirements.
  3. PCB milling uses a two or three-axis mechanical milling system to mill away the copper foil from the substrate. A PCB milling machine (referred to as a 'PCB Prototyper') operates in a similar way to a plotter, receiving commands from the host software that control the position of the milling head in the x, y, and (if relevant) z axis. Data to drive the Prototyper is extracted from files generated in PCB design software and stored in HPGL or Gerber file format.

"Additive" processes also exist. The most common is the "semi-additive" process. In this version, the unpatterned board has a thin layer of copper already on it. A reverse mask is then applied. (Unlike a subtractive process mask, this mask exposes those parts of the substrate that will eventually become the traces.) Additional copper is then plated onto the board in the unmasked areas; copper may be plated to any desired weight. Tin-lead or other surface platings are then applied. The mask is stripped away and a brief etching step removes the now-exposed original copper laminate from the board, isolating the individual traces. Screen-printing, also known as silkscreening or serigraphy, is a printmaking technique that creates a sharp-edged single-color image using a stencil and a porous fabric. ... An electronic circuit consisting of several different levels of components; printed circuits, semiconductors, resistors, capacitors etc. ... Photoengraving also known as photo-chemical milling is a process of engraving using photographic techniques. ... A photoplotter is an electro-mechanical-optical machine that produces a latent image on a media, usually high-contrast monochromatic (black-and-white) photographic film, using a light source under computer control. ... Computer-aided manufacturing (CAM) is the use of computer-based software tools that assist engineers and machinists in manufacturing or prototyping product components. ... PCB Milling basics Printed Circuit Board Milling is the process of removing areas of copper from a sheet of printed circuit board material to recreate the pads, traces and structures found in the PC boards layout file data. ... For other uses, see Plot. ... HPGL, sometimes hyphenated as HP-GL, is the primary printer control language used by Hewlett-Packard plotters. ... A Gerber File is a standard file format used by printed circuit board (PCB) fabrication houses that contains information necessary for computer controlled machines to draw exact patterns for circuit boards. ...


The additive process is commonly used for multi-layer boards as it facilitates the plating-through of the holes (to produce conductive vias) in the circuit board. In printed circuit board design, via refers to a pad with a plated hole that connects copper tracks from one layer of the board to other layer(s). ...


Lamination

Some PCBs have trace layers inside the PCB and are called multi-layer PCBs. These are formed by bonding together separately etched thin boards.


Drilling

Holes, or vias, through a PCB are typically drilled with tiny drill bits made of solid tungsten carbide. The drilling is performed by automated drilling machines with placement controlled by a drill tape or drill file. These computer-generated files are also called numerically controlled drill (NCD) files or "Excellon files". The drill file describes the location and size of each drilled hole. In printed circuit board design, via refers to a pad with a plated hole that connects copper tracks from one layer of the board to other layer(s). ... Monotungsten carbide, WC, or Ditungsten Carbide, W2C, is a chemical compound containing tungsten and carbon, similar to titanium carbide. ... This article does not cite any references or sources. ... A Drilling machine at a construction site with a concrete pump and a barely visible concrete mixer. ... Excellon file: A text-based computer data file which is used to control the actions of a CNC drilling machine, commonly used in the drilling of printed circuit boards. ...


When very small vias are required, drilling with mechanical bits is costly because of high rates of wear and breakage. In this case, the vias may be evaporated by lasers. Laser-drilled vias typically have an inferior surface finish inside the hole. These holes are called micro vias. For other uses, see Laser (disambiguation). ...


It is also possible with controlled-depth drilling, laser drilling, or by pre-drilling the individual sheets of the PCB before lamination, to produce holes that connect only some of the copper layers, rather than passing through the entire board. These holes are called blind vias when they connect an internal copper layer to an outer layer, or buried vias when they connect two or more internal copper layers and no outer layers.


The walls of the holes, for boards with 2 or more layers, are plated with copper to form plated-through holes that electrically connect the conducting layers of the PCB. For multilayer boards, those with 4 layers or more, drilling typically produces a smear comprised of the bonding agent in the laminate system. Before the holes can be plated through, this smear must be removed by a chemical de-smear process, or by plasma-etch.


Exposed conductor plating and coating

The places to which components will be mounted are typically plated, because bare copper oxidizes quickly, and therefore is not readily solderable. Traditionally, any exposed copper was plated with solder by hot air solder levelling (HASL). This solder was a tin-lead alloy, however new solder compounds are now used to achieve compliance with the RoHS directive in the EU, which restricts the use of lead. Other platings used are OSP (organic surface protectant), immersion silver (IAg), immersion tin, electroless nickel with immersion gold coating (ENIG), and direct gold. Edge connectors, placed along one edge of some boards, are often gold plated. A solder is a fusible metal alloy, with a melting point or melting range of 180-190°C (360-370 °F), which is melted to join metallic surfaces, especially in the fields of electronics and plumbing, in a process called soldering. ... This article is about the metallic chemical element. ... General Name, Symbol, Number lead, Pb, 82 Chemical series Post-transition metals or poor metals Group, Period, Block 14, 6, p Appearance bluish gray Standard atomic weight 207. ... The Restriction of Hazardous Substances Directive (ROHS) became European Law in February 2003. ... Wikiquote has a collection of quotations by or about: European Union The European Union On-Line Official EU website, europa. ... IAG may mean: International Adventure Group, A select group of individuals dedicated to international adventures Louvain School of Management - Institut dAdministration et de Gestion idiopathic adolescent gynecomastia Iraq Assistance Group, (IAG) Investment Analysis Group at the Leonard N. Stern School of Business, New York University The Information Architecture Group... Dr Mary G. Enig (circa 2000). ... An edge connector is a type of electrical connector for use with PC boards. ... Gold plating is a method of depositing a thin layer of gold on the surface of other metal, most often copper or silver, by chemical or electrochemical means. ...


Electrochemical migration (ECM) is the growth of conductive metal filaments on or in a printed circuit board (PCB) under the influence of a DC voltage bias.[1][2]


Solder resist

Areas that should not be soldered to may be covered with a polymer solder resist (solder mask) coating. The solder resist prevents solder from bridging between conductors and thereby creating short circuits. Solder resist also provides some protection from the environment.


Screen printing

Line art and text may be printed onto the outer surfaces of a PCB by screen printing. When space permits, the screen print text can indicate component designators, switch setting requirements, test points, and other features helpful in assembling, testing, and servicing the circuit board. Screen-printing, also known as silkscreening or serigraphy, is a printmaking technique that creates a sharp-edged single-color image using a stencil and a porous fabric. ... The circuit diagram for a 4 bit TTL counter, a type of state machine A circuit diagram (also known as an electrical diagram, elementary diagram, or electronic schematic) is a simplified conventional pictorial representation of an electrical circuit. ...


Screen print is also known as the silk screen, or, in one sided PCBs, the red print.


Lately some digital printing solutions have been developed to substitute the traditional screen printing process. This technology allows printing variable data onto the PCB, including serialization and barcode information for traceability purposes.


Test

Unpopulated boards may be subjected to a bare-board test where each circuit connection (as defined in a netlist) is verified as correct on the finished board. For high-volume production, a Bed of nails tester, a fixture or a Rigid needle adapter is used to make contact with copper lands or holes on one or both sides of the board to facilitate testing. A computer will instruct the electrical test unit to send a small amount of current through each contact point on the bed-of-nails as required, and verify that such current can be seen on the other appropriate contact points. A "short" on a board would be a solid connection where there should be no connection. An "open" is between two points that should be connected and are not. For small- or medium-volume boards, flying-probe and flying-grid testers use moving test heads to make contact with the copper/silver/gold/solder lands or holes to verify the electrical connectivity of the board under test. A traditional bed of nails tester is a test fixture comprising pins inserted into holes in an acrylic plate which are aligned to make contact with test points on a printed circuit board and are also connected to a measuring unit by wires. ... Function mode of a Rigid Needle Adapter. ...


Printed circuit assembly

After the printed circuit board (PCB) is completed, electronic components must be attached to form a functional printed circuit assembly, or PCA (sometimes called a "printed circuit board assembly" PCBA). In through-hole construction, component leads are inserted in holes. In surface-mount construction, the components are placed on pads or lands on the outer surfaces of the PCB. In both kinds of construction, component leads are electrically and mechanically fixed to the board with a molten metal solder. Surface-mount components on a keydrives circuit board Surface mount technology (SMT) is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards (PCBs). ...


There are a variety of soldering techniques used to attach components to a PCB. High volume production is usually done with machine placement and bulk wave soldering or reflow ovens, but skilled technicians are able to solder very tiny parts (for instance 0201 packages which are 0.02" by 0.01") by hand under a microscope tweezers and a fine tip soldering iron for small volume prototypes. Some parts are impossible to solder by hand, such as Ball Grid Array (BGA) packages. (De)soldering a contact from a wire. ... Using a soldering iron. ... For the Bulgarian Go Association, see Bulgarian Go Association. ...


Often, through-hole and surface-mount construction must be combined in a single PCA because some required components are available only in surface-mount packages, while others are available only in through-hole packages. Another reason to use both methods is that through-hole mounting can provide needed strength for components likely to endure physical stress, while components that are expected to go untouched will take up less space using surface-mount techniques.


After the board is populated, the populated board may be tested.

  • while the power is off, visual inspection, automated optical inspection. JEDEC guidelines for PCB component placement, soldering, and inspection are commonly used to maintain quality control in this stage of PCB manufacturing.
  • while the power is off, analog signature analysis, power-off testing.
  • while the power is on, in-circuit test, where physical measurements (i.e. voltage, frequency) can be done.
  • while the power is on, functional test, just checking if the PCB does what it had been designed for.

To facilitate these tests, PCBs may be designed with extra pads to make temporary connections. Sometimes these pads must be isolated with resistors. The in-circuit test may also exercise boundary scan test features of some components. In-circuit test systems may also be used to program nonvolatile memory components on the board. This article or section contains too much jargon and may need simplification or further explanation. ... JEDEC stands for Joint Electron Device Engineering Council and is the semiconductor engineering standardization body of the Electronic Industries Alliance (EIA), a trade association that represents all areas of the electronics industry. ... For the Jurassic 5 album, see Quality Control (album) In engineering and manufacturing, quality control and quality engineering are involved in developing systems to ensure products or services are designed and produced to meet or exceed customer requirements. ... In software engineering, an acceptance test is the process of the user testing the system and, based on the results, either granting or refusing acceptance of the software/system being tested. ... Boundary scan is a method for testing interconnects (thin wire lines) on printed circuit boards or sub-blocks inside an integrated circuit. ...


In boundary scan testing, test circuits integrated into various ICs on the board form temporary connections between the PCB traces to test that the ICs are mounted correctly. Boundary scan testing requires that all the ICs to be tested use a standard test configuration procedure, the most common one being the Joint Test Action Group (JTAG) standard. JTAG, an acronym for Joint Test Action Group, is the usual name used for the IEEE 1149. ...


When boards fail the test, technicians may desolder and replace failed components (professionel term: rework). Solders can be removed using a vacuum plunger (on the right) and a soldering iron. ... Rework is a term used in several contexts. ...


Protection and packaging

PCBs intended for extreme environments often have a conformal coat, which is applied by dipping or spraying after the components have been soldered. The coat prevents corrosion and leakage currents or shorting due to condensation. The earliest conformal coats were wax. Modern conformal coats are usually dips of dilute solutions of silicone rubber, polyurethane, acrylic, or epoxy. Some are engineering plastics sputtered onto the PCB in a vacuum chamber. For other uses, see Wax (disambiguation). ...


Many assembled PCBs are static sensitive, and therefore must be placed in antistatic bags during transport. When handling these boards, the user must be earthed; failure to do this might transmit an accumulated static charge through the board, damaging or destroying it. Even bare boards are sometimes static sensitive. Traces have gotten so fine that it's quite possible to blow an etch off the board (or change its characteristics) with a static charge. This is especially true on non-traditional PCBs such as MCMs and microwave PCBs. Electrostatic discharge (ESD) is the sudden and momentary electric current that flows between two objects at different electrical potentials. ... An antistatic bag is a shipping bag for devices (usually electronic) which can be damaged by electrostatic discharge. ... It has been suggested that Ground conductor be merged into this article or section. ... POWER5 MCM with four processors and four 36 MB external L3 cache modules on a ceramic substrate. ... This article is about the type of Electromagnetic radiation. ...


Safety certification (US)

Safety Standard UL 796 covers component safety requirements for printed wiring boards for use as components in devices or appliances. Testing analyzes characteristics such as flammability, maximum operating temperature, electrical tracking, heat deflection, and direct support of live electrical parts.


The boards may use organic or inorganic base materials in a single or multilayer, rigid or flexible form. Circuitry construction may include etched, die stamped, precut, flush press, additive, and plated conductor techniques. Printed-component parts may be used.


The suitability of the pattern parameters, temperature and maximum solder limits shall be determined in accordance with the applicable end-product construction and requirements.


"Cordwood" construction

Cordwood construction can give large space-saving advantages and was often used with wire-ended components in applications where space was at a premium (such as missile guidance and telemetry systems). In 'cordwood' construction, two leaded components are mounted axially between two parallel planes. Instead of soldering the components, they were connected to other components by thin nickel tapes welded at right angles onto the component leads. To avoid shorting together of different interconnection layers, thin insulating cards were placed between them. Perforations or holes in the cards would allow component leads to project through to the next interconnection layer. One disadvantage of this system was that special nickel leaded components had to be used to allow the interconnecting welds to be made. Some versions of cordwood construction used single sided PCBs as the interconnection method (as pictured). This meant that normal leaded components could be used. A through-hole component, also spelled thru-hole, is an Electronic component that has pins designed to be inserted into holes and soldered to pads on a printed board. ... For other uses, see Nickel (disambiguation). ...


Before the advent of integrated circuits, this method allowed the highest possible component packing density; because of this, it was used by a number of computer vendors including Control Data Corporation. The cordwood method of construction now appears to have fallen into disuse, probably because high packing densities can be more easily achieved using surface mount techniques and integrated circuits. Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips (EPROM memory) with a transparent window, showing the integrated circuit inside. ... This article is about the machine. ... Control Data Corporation (CDC), was one of the pioneering supercomputer firms. ... Surface-mount components on a keydrives circuit board Surface mount technology (SMT) is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards (PCBs). ...

A cordwood module.

Image File history File links Download high resolution version (1798x571, 527 KB) Summary Electronics module exhibiting w:cordwood construction. ... Image File history File links Download high resolution version (1798x571, 527 KB) Summary Electronics module exhibiting w:cordwood construction. ...

Multiwire boards

Multiwire is a patented technique of interconnection which uses machine-routed insulated wires embedded in a non-conducting matrix (often plastic resin). It was used during the 1980s and 1990s. (Augat Inc., U.S. Patent 4,648,180)


Since it was quite easy to stack interconnections (wires) inside the embedding matrix, the approach allowed designers to forget completely about the routing of wires (usually a time-consuming operation of PCB design): Anywhere the designer needs a connection, the machine will draw a wire in straight line from one location/pin to another. This led to very short design times (no complex algorithms to use even for high density designs), reduced cross talk (an electrical phenomenon appearing where a current in one wire generates another current in another conductor, that is highly amplified when wires are parallel - this nearly never happens in Multiwire), but the cost is too high to compete with cheaper PCB technologies when large quantities are needed.


Surface-mount technology

Surface mount components, including resistors, transistors and an integrated circuit.

Surface-mount technology was developed 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 directly soldered to the surface of the PCB. Components became much smaller and component placement on both sides of the board became far more common with surface-mounting than through-hole mounting, allowing much higher circuit densities. Surface mounting lends itself well to a high degree of automation, reducing labour cost and greatly increasing production and quality rates. Surface mount devices (SMDs) can be one-quarter to one-tenth the size and weight, and passive components can be one-half to one-quarter the cost of through-hole parts. Integrated circuits (where the chip itself is the most expensive part) are often priced the same regardless of package type however. As of 2006, some wire-ended components, such as small signal switch diodes, e.g. 1N4148, are actually significantly cheaper than corresponding SMD versions. Surface-mount components on a flash drives circuit board Surface mount technology (SMT) is a method for constructing electronic circuits in which the components (SMC, or Surface Mounted Components) are mounted directly onto the surface of printed circuit boards (PCBs). ... Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... Resistor symbols (American) Resistor symbols (Europe, IEC) Axial-lead resistors on tape. ... Assorted discrete transistors A transistor is a semiconductor device, commonly used as an amplifier or an electrically controlled switch. ... Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips (EPROM memory) with a transparent window, showing the integrated circuit inside. ... Surface-mount components on a flash drives circuit board Surface mount technology (SMT) is a method for constructing electronic circuits in which the components (SMC, or Surface Mounted Components) are mounted directly onto the surface of printed circuit boards (PCBs). ...


See also

Electronics Portal
PCB Materials
  • Laminate materials:
    • FR-4, the most common PCB material
    • FR-2
    • Composite epoxy material, CEM-1,5
    • Polyimide
    • GETEK
    • BT-Epoxy
    • Cyanate Ester
    • Pyralux, a material for flexible printed circuits
    • PTFE, Polytetrafluoroethylene
    • Rogers Bendflex
  • Conductive ink
  • Metal Core PCB, for high temperature
PCB software
Schematic Capture. (KICAD)
PCB layout. (KICAD)
3D View. (KICAD)
Main article: List of EDA companies

Image File history File links Nuvola_apps_ksim. ... A breadboard with a completed circuit A breadboard is a reusable solderless device used to build a (generally temporary) prototype of an electronic circuit and for experimenting with circuit designs. ... There are very few or no other articles that link to this one. ... An (orange-epoxy) encapsulated hybrid circuit on a printed circuit board. ... POWER5 MCM with four processors and four 36 MB external L3 cache modules on a ceramic substrate. ... This article or section does not cite any references or sources. ... In science and engineering, conductors, such as copper or aluminum, are materials with atoms having loosely held valence electrons. ... Laminate flooring Laminated core transformer A laminate is a material constructed by uniting two or more layers of material together. ... FR-4, an abbreviation for Flame Retardant 4, is a type of material used for making a printed circuit board (PCB). ... FR-2 is an abbreviation for Flame Resistant 2. ... Polyimide (sometimes abbreviated PI) is a polymer of imide monomers. ... BT-Epoxy belongs to the group of of thermoset resins used in printed circuit boards(PCBs). ... Cyanate esters are chemical substances generally based on a bisphenol derivative, in which the hydrogen atom of the phenolic OH group is substituted by a cyanide group. ... Teflon is the brand name of a polymer compound discovered by Roy J. Plunkett (1910-1994) of DuPont in 1938 and introduced as a commercial product in 1946. ... Conductive ink is an ink that is conductive, allowing a circuit to be drawn or printed on a variety of materials including paper. ... Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1017 × 678 pixels, file size: 148 KB, MIME type: image/jpeg) KICAD Eeschema Screenshot. ... Image File history File links Size of this preview: 800 × 533 pixelsFull resolution (1017 × 678 pixels, file size: 148 KB, MIME type: image/jpeg) KICAD Eeschema Screenshot. ... Image File history File links Size of this preview: 800 × 569 pixelsFull resolution (923 × 656 pixels, file size: 183 KB, MIME type: image/jpeg) KICAD PCBnew Screenshot. ... Image File history File links Size of this preview: 800 × 569 pixelsFull resolution (923 × 656 pixels, file size: 183 KB, MIME type: image/jpeg) KICAD PCBnew Screenshot. ... Image File history File links Size of this preview: 790 × 600 pixelsFull resolution (871 × 661 pixels, file size: 229 KB, MIME type: image/jpeg) 3D View available inside KICAD PCBnew. ... Image File history File links Size of this preview: 790 × 600 pixelsFull resolution (871 × 661 pixels, file size: 229 KB, MIME type: image/jpeg) 3D View available inside KICAD PCBnew. ... A comprehensive list of electronic design automation (EDA) Companies can be compiled from lists of vendors-exhibitors of DAC (Design Automation Conference) held yearly for more than 30 years. ... EDWinXP or Electronic Design for Windows is a commercially available PCB design integrated CAD/CAE package. ... Autotrax EDA is an electronic design automation software made by Kovac Software with a download base of over 60 000 people, and is used in many educational institutions due to it being free. ... EAGLE (Easily Applicable Graphical Layout Editor) is an ECAD program produced by Cadsoft in Germany (American marketing division: Cadsoft USA). ... EAGLE (Easily Applicable Graphical Layout Editor) is an ECAD program produced by Cadsoft in Germany (American marketing division: Cadsoft USA). ... For other uses, see Open source (disambiguation). ... Cadstar is an EDA software for designing and creating electronic boards. ... Zuken Inc. ... CR5000 is the flagship PCB design package of Zuken Inc. ... Zuken Inc. ... The National Instruments Campus in Austin, Texas National Instruments NASDAQ: NATI is a producer of virtual instrumentation software. ... The National Instruments Campus in Austin, Texas National Instruments, or NI (NASDAQ: NATI), is a producer of automated test equipment and virtual instrumentation software. ... The gEDA project is a free, open-source, collaborative software project aiming to produce a full GPL’d suite of electronic design automation tools. ... For other uses, see Open source (disambiguation). ... An ORCAD Electrical system diagram; Typically OrCAD is used with Electronic components such as ICs, Etc. ... Allegro may mean: a musical tempo Allegro library, a computer game programming library Allegro (airline), a charter airline based in Mexico City Allegro (auction), a Polish online auction website, also known as Aukro (Czech Republic), TeszVesz (Hungary) and Av-Av (Russia and Ukraine) Allegro (musical), a 1947 musical by Rodgers... Cadence Design Systems, Inc (Nasdaq: CDN, NYSE: CDN) is an electronic design automation (EDA) software company, founded in 1988 by the merger of SDA Systems and ECAD. As of 2004, Cadence is the worlds largest supplier of electronic design technologies and engineering services. ... -1... KiCad is an open source software suite for EDA - designing schematics of electronic circuits and printed circuit boards (PCB). ... This article or section reads like an advertisement. ...

References

  1. ^ IPC Publication IPC-TR-476A, “Electrochemical Migration: Electrically Induced Failures in Printed Wiring Assemblies,” Northbrook, IL, May 1997.
  2. ^ S.Zhan, M. H. Azarian and M. Pecht, "Reliability Issues of No-Clean Flux Technology with Lead-free Solder Alloy for High Density Printed Circuit Boards", 38th International Symposium on Microelectronics, pp. 367-375, Philadelphia, PA, September 25-29, 2005.
  • Coombs, Clyde F., Jr. (Ed.) (1995). Printed Circuits Handbook, Fourth Edition, McGraw-Hill ISBN 0-07-012754-9.
  • Coombs, Clyde F., Jr. (Ed.) (2001). Printed Circuits Handbook, Fifth Edition" ', McGraw-Hill Professional ISBN 0-07-135016-0.
  • Coombs, Clyde F., Jr. (Ed.) (2007). Printed Circuits Handbook, Sixth Edition" ', McGraw-Hill Professional ISBN 0-07-146734-3.

IPC, the Association Connecting Electronics Industries (formerly known as the Institute for Interconnecting and Packaging Electronic Circuits), is an organization whose aim is to standardize the assembly and production requirements of electronic equipment and assemblies. ...

External links

Wikibooks Practical Electronics has a page on the topic of
Wikimedia Commons has media related to:

Image File history File links Wikibooks-logo-en. ... Wikibooks logo Wikibooks, previously called Wikimedia Free Textbook Project and Wikimedia-Textbooks, is a wiki for the creation of books. ...

Design guidelines

Standards and specifications

  • Association Connecting Electronics Industries (IPC)
  • MIL-PRF-31032, Performance Specification Printed Circuit Board/Printed Wiring Board
  • MIL-PRF-55110, Performance Specification for Rigid Printed Circuit Board/Printed Wiring Board
  • MIL-PRF-50884, Performance Specification for Flexible and Rigid-Flexible Printed Circuit Board/Printed Wiring Board

Do-it-yourself (DIY) guides

  • Making PCBs using photo etching method
  • Making PCBs using DIY cnc hardware
  • Making PCBs with a laser printer and photo paper, no UV machine needed anymore.
  • More detailed PCB DIY making with laser printer
  • Making PCBs by hand using an etch-resist pen (no printer or special paper needed)
  • PCB router (open hardware).

Open Hardware (OH) is a part of the GNU project in which hardware designers share their work by disclosing the schematics and software (GNU drivers) used in their designs. ...

Others


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Printed Circuit Board Fabrication and Assembly (762 words)
These Printed Circuits Boards (PCBs) are exposed to such extreme environments as high radiation, humidity, and cryogenic temperatures in a wide variety of experiments.
The printed circuit board fabrication group produces custom circuit boards from the engineer’s initial design to the finished board, with the capability to produce features such as fine holes for via structures and components, ultra fine width and pitch conductive circuit traces.
The circuit board assembly group in Instrumentation is a cost-effective means of assembling specialized custom circuit boards or for performing any kind of rework on existing fixtures or off-the-shelf electronics.
Printed Circuit Board | Terminology Glossary (972 words)
Edge Connector – is a connector on the circuit substrate edge in the form of plated pads or lines of coated holes used to connect other circuit board or electronic device.
In-Circuit Test – is the electrical testing of individual components or parts of a circuit board rather than testing the whole circuit.
Lamination - Many printed circuit boards are made up of multiple layers, these are referred to as multi-layer printed circuit boards.
  More results at FactBites »

 
 

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