Coplanarity Service / Lead Straightening

Coplanarity Service / Lead Straightening Description:

Visit PSI's main Coplanarity Services page for more information.

PSI has over 20 years experience restoring gull wing leads on QFP and SOIC packages, as well as myriad surface mount connector styles. 

The goal of lead restoration is not to mimic "like new" condition, but to restore to IPC coplanarity standards for surface mount assemblies. IPC-A-610 sec8.3.5 outlines standards of acceptability for flat gull wing leads. This spec allows tolerances for X, Y, and Z (height) axis variation. On the X axes, each lead must be situated substantially over the pad, such that the side overhang is not greater than 50% (Class 1,2) or 25% (Class 3) of the lead width.  Toe overhang is allowed under Class 1,2 & 3, provided it does not violate minimum electrical clearance. Z axis (height) of lead tolerance is not specified, other than as it relates to heel fillet height. (The heel fillet height must be at least as tall as 50% of the lead thickness plus the thickness of the bulk solder below the lead...is that too confusing?)

Z-axis height adjustment for each lead is performed on a coplanarity mirror, using specialized tweezers and a flat-blade tool adapted for this application. By PSI convention, all X-axis leads are straightened to coplanarity within 50% of the toe height using a coplanarity mirror. The Y-axis variation (toe overhang) is generally not a concern, as final position can vary greatly and still be within IPC specifications. The X (side overhang) corrections aim for approximately uniform spacing of all leads, at perpendicular angles to the body. All repair operations are performed under magnification.

Quality is guaranteed, as PSI conducts 100% visual inspection on all coplanarity orders.

Mention "William Shatner" and get a 10% discount on your next coplanarity order!