Solder joint inspection features

A printed circuit board (PCB) comprising:

• a substrate having a surface;
• a solder pad formed as a single continuous metallized region on the substrate surface and extending along an axial direction from a proximal end portion to a distal end portion, the solder pad having a first lateral width measured transverse to the axial direction and defining a longitudinal centerline extending along the axial direction;
• a slot formed through the substrate at the proximal end portion;
• a magnet conductor wire routed through the slot and extending onto the solder pad from the proximal end portion toward the distal end portion;
• and
• a pair of opposed notches formed in and recessed inward from opposing lateral sides of the solder pad at a common axial location between the proximal end portion and the distal end portion and symmetrically disposed about the longitudinal centerline,
• wherein:
• the opposed notches define a transverse constriction region of the solder pad having a second lateral width that is less than the first lateral width,
• the transverse constriction region extends between the opposing lateral sides of the solder pad and is positioned between ten percent and fifty percent of the axial length of the solder pad measured from the proximal end portion, and
• the transverse constriction region defines a visible axial boundary of solder coverage for visual inspection of solder flow from the proximal end portion toward the distal end portion.

A printed circuit board (PCB) comprising:

• a substrate having a surface;
• a solder pad formed as a single continuous metallized region on the substrate surface and extending along an axial direction from a proximal end portion to a distal end portion, the solder pad having an axial length and a first lateral width measured transverse to the axial direction and defining a longitudinal centerline extending along the axial direction;
• a slot formed through the substrate at the proximal end portion;
• a magnet conductor wire routed through the slot and extending onto the solder pad from the proximal end portion toward the distal end portion, the magnet conductor wire having an end portion disposed on the solder pad;
• a fiducial marking formed on the substrate surface adjacent to the solder pad, the fiducial marking extending along a transverse direction relative to the axial direction of the solder pad and having an axial length less than the axial length of the solder pad, the fiducial marking being positioned such that the fiducial marking is visually transposed onto the solder pad to define a bounded conductor end zone on the solder pad;
• and
• a pair of opposed notches formed in and recessed inward from opposing lateral sides of the solder pad at a common axial location between the proximal end portion and the distal end portion and symmetrically disposed about the longitudinal centerline of the solder pad,
• wherein:
• the bounded conductor end zone is located axially spaced from the slot and defines an axial overlap region for positioning the end portion of the magnet conductor wire on the solder pad prior to soldering;
• the opposed notches define a transverse constriction region of the solder pad having a second lateral width that is less than the first lateral width;
• the transverse constriction region is located between about thirty percent and about fifty percent of the axial length of the solder pad measured from the proximal end portion;
• and
• the transverse constriction region defines a visible axial boundary of solder coverage for inspection of solder extending from the proximal end portion toward the distal end portion.