Q
We are having problems achieving adequate heel fillets when soldering this
device which we know is due to difficulties in getting enough solder paste on
to the pad. Do you have a recommended pad size for this component ? Any other
comments which may help ?
A
We do not issue recommendations on land patterns because these are partially
dependent on the board design rules used, and on the soldering processes used
by the board assemblers.
You can find the standard layout for specific solder land patterns at the
website of the IPC (Institute for Interconnecting and Packaging Electronic
Circuits). at
http://www.ipc.org/
Under "Design" your customer will find a land pattern calculator that will
enable him to view the patterns in the current standard as well as calculate
new patterns from component data. It contains a user searchable database of
patterns for components not yet approved by EIA or EIAJ.
Alternatively he can go directly to the list of IPC, publications at
http://www.ipc.org/html/designpubs.htm
and scroll down to IPC-SM-782A - the Surface Mount Design and
Land Pattern Standard. The updated IPC-SM-782A (1993) contains a set of
requirements for calculating land patterns. It walks the user through sample
calculations and clearly defines the component dimension requirements