4 Apr
2011
4 Apr
'11
12:33 p.m.
A properly designed multi-layer board should be using
thermal reliefs
around the Gnd and +V pins, but I'm not sure how much that is done in
consumer equipment. Its a cross-shaped structure intended to provide
thermal resistance between the via and the body of the internal plane.
Theyr'e certianly used in the older HP stuff I spend a lot of time
repairing (you can see the cross structure aroudn the pin if you hold the
PCB up to a storng light source), but even so I do find the pins
connected to the power/grounds planes take a little more effort to
desolder than the other.
-tony