Printed Wiring

Printed Wiring

 

a method of wiring electronic apparatus in which the connections between electric and electronic components, including shields, are made by means of fine conductive strips with contact areas that are arranged on a printed circuit board. Printed wiring makes possible a reduction in the size and weight of apparatus and the use of mechanized and automated equipment and highly efficient processes for mass production. In addition, the reliability of the items is improved, and material outlays and labor costs are reduced.

Printed conductors are produced by etching metal-clad insulating material, by electrochemical deposition, by vacuum or cathode sputtering, by baking on conductive inks, and by electroplating, with transfer of the conducting pattern to an insulating board. The image of the printed conductors is printed on a board by photographic, offset, and screening methods, as well as molding, and embossing. Continuity of contacts between the two sides of a board is produced by plating the walls of the holes or by inserting metal tubes, which are subsequently flared and soldered. The conductors in printed wiring are usually 20–50 microns thick and 0.5–0.8 mm wide; the minimum distance between conductors is 0.3–0.5 mm. As a result of favorable heat-removal conditions, high current density (up to 30–50 amperes per sq mm) is permissible in printed conductors. Multilayer printed-circuit boards are used for microminiaturization of apparatus based on multiple-output integrated circuits, thus achieving a substantial increase in circuit density.

REFERENCES

Belevtsev, A. T. Tekhnologiia proizvodstva radioapparatury. Moscow, 1971.
Arenkov, A. B. Pechatnye i plenochnye elementy radioelektronnoi apparatury. Leningrad, 1971.

B. P. LIKHOVETSKII

References in periodicals archive ?
TOK produces manufacturing materials, mainly photoresists and high purity chemicals for photolithography processing of semiconductor, flat panel display and printed wiring board fabrication; processing equipment for semiconductor and liquid crystal display manufacturing; printing materials; and inorganic and organic chemicals.
a global supplier of specialty metalization chemistries to producers of printed wiring boards.
FTG Circuits - Chatsworth has received DSCC Mil-P-50884, type 4 "adhesiveless" with "etchback", certification for the manufacture of rigid-flex and flexible printed wiring board products (QPL test reference # 50884-1315-112908).
The Dii management team is now concentrating solely on our three core competencies of design and semiconductor services, printed wiring board fabrication, and systems assembly and distribution.
A printed wiring board (PWB) is the foundation both literally and figuratively for virtually all electronics in the world.
Firan Technology Group Corporation (TSX: FTG) said that it has been awarded a new multi-year enterprise sourcing agreement from Rockwell Collins for the supply of printed wiring boards.
R&D Circuits is a leading manufacturer of technologically advanced printed wiring boards for the ATE industry.
HCSZ"), a subsidiary of Hitachi Chemical of Japan, has invested approximately two billion yen to build a second production line of photosensitive dry films for printed wiring boards within HCSZ compound with doubled production capacity and began full-scale operation as the demand increased.
The objective of this investigation was to conduct a feasibility study using a full-rate production avionics product to determine printed wiring board design and potential printed wiring assembly issues/concerns when using Pb-free soldering processes/procedures for military avionics products.
DNP'; TSE: 7912) and Unimicron Technology Corporation (TW: 3037), the globally renowned Taiwan based maker of printed wiring boards, are pleased to announce an agreement on the establishment in late June 2008 in Hong Kong, of UD Alliance Technology Limited, a joint venture between the two companies, which will specialize in the manufacturing and marketing of printed wiring boards based on B2it(TM), DNP's unique buildup board manufacturing technology.
The company will continue to develop and manufacture coated and/or laminated substrates for applications in printed wiring boards, flexible circuits, optical films for displays, and high temperature, conductive and shielding tapes.
Materials for rigid and flexible printed wiring boards.