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A minimum of .020" (0,50 mm) is usually
required, from the bottom of the lead to the bottom of the
insulator, to assure adequate room for board cleaning and solder joint
inspection. Standoffs are not required on surface mount interconnects
with large cross-section tails. The connector leads sit on the board rather
than passing through it providing the necessary stand-off. Leads that
are at least 0.020" (0.50mm) in thickness have adequate structural
strength to handle normal insertion and withdrawal without distortion.
However, many micro sockets have leads that are only .005" (0,13mm)
thick. For leads with these small cross sections, standoffs built into
the insulator are recommended to absorb the stress of insertion. Additionally,
they help protect the solder paste from being displaced off of the pad
during placement.solder joints.
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