On Sat, 31 Dec 2005 15:26:33 +0100, bob_ledoux <
bobledoux@...>
wrote:
>
>
> The whole design concept changes when making surface mount boards.
>
> Much less surface area, and less soldering heat, is required when you
>
> don't pass a wire through the board.
And, usually, the forces on the pads are much smaller. A 1206 resistor
doesn't pull much, even of you apply a insane amount of G's.
OTOH i don't quite trust SMD connectors and stuff, i still make those
throughhole. They might just come off if abused.
Pads usually only lift during repair/rework anyway if the thing is
designed properly never during normal use.
When i repaired a mobile phone not long ago i found a 8 pin SMD IC ripped
off the PCB and stuck to a piece of foam applied to the back cover.
Apparently the glue holding on the foam had soaked through, and stuck the
SMD to the back cover better than the pads to the board.
Was only a comparator used for detecting the presence of a headset and
instead of hunting down the right traces and wiring it in again i just
hardwired the phone for no headset.
ST