Basic noun explanation of SMT (1)

- Aug 18, 2018-


Accuracy: the difference between the measurement result and the target value. 

Additive Process: a method of manufacturing PCB conductive wiring by selectively applying conductive materials (copper, tin, etc.) to the substrate. 

Adhesion: attraction between molecules. 

Aerosol: a liquid or gaseous particle small enough to be airborne. 

Angle of attack: the Angle between the surface of a printing scraper and the plane of a steel plate. 

Anisotropic adhesive (different to the photoresist or conductive adhesive) : a conductive material, the particle is only through the current in the Z axis direction. 

Annular ring: a conductive material around the hole. 

Application specific integrated circuit (ASIC special Application integrated circuit) : a circuit customized for a specific purpose. 

Array: a set of elements, such as a solder ball point, arranged in rows and columns. 

Artwork(wiring diagram) : the conductive wiring diagram of the PCB for producing the original photo. It can be produced in any proportion, but usually is 3:1 or 4:1. 

Automated test equipment (ATE) : a device designed for automatic analysis or static parameters and also for fault segregation to assess performance levels. 

Automatic optical inspection: on Automatic systems, a camera is used to inspect a model or object. 


Ball grid array (BGA grid array) : a wrapper form of an integrated circuit whose input and output points are a grid pattern of tin balls arranged on the underside of the component. 

Blind via(Blind access hole) : conductive connection between the outer and inner layers of a PCB that does not continue to reach the other side of the board. 

Bond lift-off: failure to separate the welding pins from the surface of the pad (circuit board base). 

Bonding agent: a adhesive that bonds a single layer to form a multilayer board. 

A solder that connects two conductors that should be electrically conductive, causing a short circuit. 

Buried via: a conductive connection between two or more inner layers of a PCB (i.e., invisible from the outer layer). 


CAD/CAM system(CAD/CAM system) : computer-aided design is the use of specialized software tools to design printed circuit structures;Computer-aided manufacturing transforms this design into actual products.These systems include large amounts of memory for data processing and storage, inputs for design creation, and output devices for converting stored information into graphics and reports

Capillary action: a natural phenomenon that causes molten solder to flow against gravity on very close solid surfaces. 

Chip on board (COB board) : a hybrid technology that USES a glued facing Chip component that is traditionally attached to the board base by flying wire. 

Circuit tester(Circuit tester) : a method of testing PCB in mass production.Includes: pin bed, component pin footprint, guide probe, internal trace, loading plate, empty plate, and component testing. 

Cladding(coating) : a thin sheet of metal foil is attached to the sheet to form a PCB conductive wiring. 

Coefficient of thermal expansion: the rate of expansion per degree of temperature (PPM) of the material measured as the surface temperature of the material increasesCold cleaning: an organic dissolving process in which residues are removed after contact with the liquid. Cold solder joint(Cold solder joint) : a weld that reflects insufficient wetting, characterized by a greyish, porous appearance due to inadequate heating or improper cleaning. Component density: the number of components on a PCB divided by the area of the board. Conductive epoxy (Conductive epoxy resin) : a kind of polymer material, by adding metal particles, usually is silver, make it through the current. Conductive ink (Conductive ink) : use glue on thick film materials, the formation of PCB Conductive wiring diagram. Conformal coating(Conformal coating) : a thin protective coating applied to PCB that is compliant to the assembly appearance. Copper foil(Copper foil) : a cathodic electrolytic material, a thin, continuous sheet of metal foil deposited on the substrate of a circuit board.

It ACTS as a conductor of electricity for the PCB.It is easily bonded to an insulating layer, accepting a printed protective layer, and corroded to form a circuit pattern.Copper mirror test(Copper mirror test) : a solder caustic test using a vacuum deposition film on a glass plate. Cure: a change in the physical properties of the material by chemical reaction, or by a pressure/pressure free reaction to heat. Cycle rate: a term for a component patch that measures the speed of a machine taken, located, and returned from the board, also known as test speed. DData recorder: a device that measures and collects temperatures at specified intervals from a thermocouple attached to a PCB. Defect(Defect) : a component or circuit unit that deviates from the accepted characteristics. Delamination(Delamination) : separation of the plate layer and separation between the plate layer and the conductive overlay layer.

Desoldering(soldering) : repair or replace the welding assembly by disassembly. The methods include: soldering with a soldering belt, vacuum (soldering straws) and hot drawing. Dewetting: the process of covering and recovering molten solder, leaving an irregular residue. DFM(manufacturing-driven design) : the most efficient way to produce a product, taking into account time, cost, and available resources. Dispersant (Dispersant) : a kind of chemicals, add water to increase its ability to particles. Documentation: data on assembly that explains basic design concepts, types and quantities of components and materials, special manufacturing instructions, and latest versions.Use three types: prototypes and small runs, standard production lines and/or production quantities, and government contracts that specify actual graphics. Downtime (Downtime) : equipment for maintenance or failure without production time of the products. Durometer: measure the rubber or plastic hardness of the blade.

EEnvironmental test(Environmental test) : a test or series of tests used to determine the overall impact of the external structure, machinery, and functional integrity of a given package or assembly of a component. Eutectic solders(Eutectic solders) : two or more metal alloys with the lowest melting point that, when heated, the Eutectic solders change directly from solid to liquid without passing through the plastic stage. FFabrication() : the manufacturing process of empty plate before assembly after design. Separate processes include lamination, metal addition/subtraction, boring, plating, wiring and cleaning. Fiducial(reference point) : a special mark combined with a circuit wiring diagram for machine vision to find the direction and position of the wiring diagram. Fillet(weld Angle) : a solder - formed connection between the pad and the assembly pin.The solder joint. Fine-pitch technology (FPT pin pitch technology) : the lead center spacing distance of the surface mount package is 0.025"(0.635mm) or less.

Fixture: a device that connects a PCB to a processing center. Flip chip: a non - pin structure that usually contains a circuit unit. Designed to be electrically and mechanically connected to a circuit through an appropriate number of tin balls located on its surface (covered by conductive binders). Full liquidus temperature(fully liquefied temperature) : the temperature level at which the solder reaches its maximum liquid state and is most suitable for good wetting. Functional test(Functional test) : it simulates the expected operating environment, and tests the electrical appliances of the whole assembly. GGolden boy: a component or circuit assembly that has been tested and known to meet technical specifications for testing other units by comparison.