Surface-mount technology, known as SMT and originally called planar mounting, is a method of mounting electrical components directly onto the surface of a printed circuit board rather than through drilled holes; a component mounted this way is called a surface-mount device. It has largely replaced through-hole construction across industry because it allows for greater manufacturing automation, which lowers cost and improves quality, and because it lets more components fit onto a given area of board, though both technologies are often used on the same board, with through-hole mounting reserved for parts unsuited to surface mounting, such as large transformers and heat-sinked power semiconductors. A surface-mount component is typically smaller than its through-hole counterpart, since it has shorter leads or none at all, and may terminate in short pins, flat contacts, a matrix of solder balls known as a ball grid array, or terminations built directly onto the body of the component.
Facts
Partially Attested
Origin YearSource says the technology was developed in the 1960s and that IBM first demonstrated the design approach in 1960; the exact year of origin is not a single fixed year Core PrincipleElectrical components are mounted directly onto the surface of a printed circuit board rather than through holes 1 FAQs
Are surface-mount solder joints as strong as through-hole joints?
Not quite: through-hole joints are generally stronger because the leads pass through the board.
Generally not. A through-hole component has leads that run through the circuit board, which gives it stronger and more durable connections, while a surface-mount component is held only by solder on the surface of the board, which can be less resilient under environmental stress. Surface mount is the better fit for automated production, and through-hole technology keeps a niche in high-reliability fields such as military and aerospace work.
Connections
Associated With
Source Reflow soldering (Wikipedia)Wikipedia contributors
In Field
Source Surface-mount technology, Wikipedia
Sources
1. Surface-mount technology, Wikipedia
Introduction, first sentence
Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB).
History section
The design approach first demonstrated by IBM in 1960 in a small-scale computer was later applied in the Launch Vehicle Digital Computer used in the Instrument Unit that guided all Saturn IB and Saturn V vehicles.
In Field: Electrical Engineering, Categories
Electronic design
In Group: Semiconductor Fabrication and Electronics Assembly, Introduction
Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB).
View the SourceReflow soldering (Wikipedia)
Wikipedia contributors, Wikimedia FoundationAssociated With: Reflow Soldering, IntroductionQuote, Associated With: Reflow Soldering, Introduction
Reflow soldering with long industrial convection ovens is the preferred method of soldering surface mount technology (SMT) components to a printed circuit board (PCB).
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