现在,总有迷茫的感觉?啥是PCB,我想开个帖子和大家交流。潜水的大牛们可以跳出来拍砖了。
PCB,= Problem Come Back。关于PCB的历史和源远流长的技术路线,在这里就不多讨论了。CPCA、TPCA都有很优秀的教材,讲述什么是PCB。我现在只想和大家从虚得方面讨论PCB,因为对PCB的迷茫将导致技术路线和技术手法的不同。
从互连角度来讲,自双面板开始,MIL就开始给孔内铜的厚度、质量进行了定义一直到今天:1mil=25um。IPC也对它进行了详细的划分:class 1; class 2; class 3;(Ref to IPC-600F)
挖坑:IPC 610-E stipulates what minimum vertical hole fill for Class 1 boards?
a. 75% on signal holes and 50% on ground holes
b. 75% on both signal and ground holes
c. 50% on both signal and ground holes
d. 75% on signal and the lesser of 50% or 1.9mm on ground holes
e. the lesser of 50% or 1.9mm on both signal and ground
f. none of the above