Major Events in Printed Circuit Board History

Major events in Printed Circuit Board history 1903 Albert Hanson described flat foil conductors laminated to an insulating board Thomas Edison used chemical methods to plate conductors into linen paper 1904 1913 Both Max Schoop and Arthur Berry patented a print and etch method to flame spray metal into a board through a patterned mask Charles Curcase patents a method of electroplating 1927 circuit patterns 1936 Paul Eisler invented the printed circuit a5 part of a radio set U.S.A. begins to use technology on a large scale to make proximity fuses for use in wW 1943 II. After the war they were releasesd for commercial use The United States Army 1949 Signal Corps invents 'auto- assembly' process in which leads are inserted into a copper foil interconnection pattern and dip soldered 1980's Small surface mount parts have been used increasingly instead of through-hole components; this has led to smaller boards for a given functionality and lower costs MID 80's While still viewed by 2: http://en.wikipedia.Org/ wiki/Printed_ciscuit_board#Hiato=y many as being too costly, Cad software is becoming more and more commonplace. High speed/signal integrity beings to hit mainstream PCB, much like surface- mount technology did in the early 1998 1980s. 2000's Conductor width and spacing has shrunk down to he 35-40 um range with 75 um pathways being more mainstream.