[sdiy] Front panel and PCB design tactics

[Byron G. Jacquot]

>But does this help a lot? There are always tolerances, in the diameter of the posts, in their distance, and last not least in the diameter of the holes in the PCB. So you have to make the holes wider than the nominal diameter of the posts. When the jack is soldered to the PCB, it's likely the the solder joints have to take all the force and not the posts.

Those little posts aren't really there for mechanical strain relief.

The SMT connectors are intended to be used on a paste & reflow assembly line.  The posts (called "bosses" in the IPC parlance) are there to keep the connector from skewing when the solder paste is liquid - the surface tension of liquid solder forms a fluid bearing, and tiny connectors float out of alignment.

The company I work for was having terrible yield on connectors due to this - particularly micro-USB.  We switched to bossed connectors and eliminated the problem.

It didn't, however, do as much to solve the problem that overzealous users can jab the connector in place, and shear the socket right off the board.

-Byron Jacquot