Re: gEDA-user: dxf again

[Bob Paddock <bob.paddock@xxxxxxxxx>]

     If you don't need the thermal pad,

   I've seen QFN's be ejected from the board, without much force, when the
   bottom pad is not soldered.  Doesn't take much twisting of a board.
   Many data sheets tell you in the foot notes that the pad must be solder
   for one or more of these reasons: Thermal, Ground, Mechanical
   Stability.

     just plunk the part on the board
     with flux and run a solder blob around the edges.  Done.

   Many QFNs can look like they have nice solder points on the edges, but
   don't actually get any real solder under the part to the pads.  These
   projects are prone to infant mortality failures.

     You will love the leadless packages if you have ever bent the pins
     or
     solder-bridged a TSSOP part.

   I've used both.  I'll take the pins.

   --
   [1]http://blog.softwaresafety.net/
   [2]http://www.designer-iii.com/
   [3]http://www.wearablesmartsensors.com/

References

   1. http://blog.softwaresafety.net/
   2. http://www.designer-iii.com/
   3. http://www.wearablesmartsensors.com/


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