Printed circuit board - General characteristics

A printed circuit board or PCB interconnects electronic components using conductive traces laminated onto a non-conductive substrate. Alternative names are printed wiring board or PWB or etched wiring board Printed circuit board - General characteristics. A printed circuit board consists of "etched conductors" attached to a sheet of insulator. The conductive pathways are called "traces" or "tracks". The insulator is called the substrate. The vast majority of 'pri ...

Including:

• Printed circuit board - General characteristics
• Printed circuit board - History
• Printed circuit board - Design
• Printed circuit board - Substrates
• Printed circuit board - Manufacture and population of conventional PCBs
• Printed circuit board - Protection and packaging
• Printed circuit board - 'Cordwood' construction
• Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia - Printed circuit board

A printed circuit board consists of "etched conductors" attached to a sheet of insulator. The conductive pathways are called "traces" or "tracks". The insulator is called the substrate. The vast majority of 'printed circuit boards' are made by adhering 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 (e.g. by etching in an acid), leaving only the desired copper traces. A few PCBs are made by adding traces to the bare subs ...

See also:

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - General characteristics

Surface-mount technology was developed in the 1960s and became widely used in the late 1980s. 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 labor cost and greatly increasing production rates. SMDs can be one-quarter to one-tenth the size and w ...

See also:

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - Surface-mount technology

Holes are drilled with tiny carbide drill bits or by lasers. Because lasers produce an inferior surface finish inside the hole, their use is generally restricted to making tiny holes where bit breakage and wear would be a serious problem; these holes are called micro vias. The drilling is performed by drilling machines with computerized placement using a "drill tape" or "drill file." A drill file is a computer file describing the location and sizes of all drilled holes. These files are also called numerically controlled drill (NCD) fi ...

See also:

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - Manufacture and population of conventional PCBs

Low-end consumer grade PCB substrates frequently are made of paper impregnated with phenolic resin, sometimes branded "Pertinax". They carry designations such as XXXP, XXXPC, and FR-2. The material is inexpensive, easy to machine by drilling, shearing and cold punching, and causes less tool wear than glass fiber reinforced substrates. The letters "FR" in the designation indicate Flame Resistance. High-end consumer and industrial circuit board substrates are typically made of a material designated FR-4. This consists of a woven fibergl ...

See also:

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - Substrates

The inventor of the printed circuit was probably the Austrian engineer Paul Eisler (1907–1995) who, while working in England, made one circa 1936 as part of a radio set. Around 1943 the USA began to use the technology on a large scale to make rugged radios for use in World War II. After the war, in 1948, the USA released the invention for commercial use. Printed circuits did not become commonplace in consumer electronics until the mid-1950s. Before printed circuits, point-to-point construction was used. For prototypes, or small ...

See also:

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - History

Usually an electronics or electrical engineer designs the circuit, and a layout specialist designs the PCB. PCB design is a specialized skill. There are numerous techniques and standards used to design a PCB that is easy to manufacture and yet small and inexpensive. Most PCBs have between one and sixteen conductive layers laminated (glued) together. Layers may be connected together through drilled holes called vias. Either the holes are electroplated or small rivets are inserted. High-density PCBs may have blind vias, which are visible only on one surface, or buried vias, which are visible on neither.

Printed circuit board, Printed circuit board - General characteristics, Printed circuit board - History, Printed circuit board - Design, Printed circuit board - Substrates, Printed circuit board - Manufacture and population of conventional PCBs, Printed circuit board - Protection and packaging, Printed circuit board - 'Cordwood' construction, Printed circuit board - Surface-mount technology

Read more here: » Printed circuit board: Encyclopedia II - Printed circuit board - Design