IRDC3629 Datasheet, PDF (15/16 Pages) International Rectifier – USER GUIDE FOR IR3629 EVALUATION BOARD

IRDC3629
Stencil Design
 The stencil apertures for the lead lands should be approximately 80% of the area of the lead lands. Reducing the
amount of solder deposited will minimize the occurrence of lead shorts. Since for 0.5mm pitch devices the leads are
only 0.25mm wide, the stencil apertures should not be made narrower; openings in stencils < 0.25mm wide are
difficult to maintain repeatable solder release.
 The stencil lead land apertures should therefore be shortened in length by 80% and centered on the lead land.
 The land pad aperture should deposit approximately 50% area of solder on the center pad. If too much solder is
deposited on the center pad the part will float and the lead lands will be open.
 The maximum length and width of the land pad stencil aperture should be equal to the solder resist opening minus
an annular 0.2mm pull back to decrease the incidence of shorting the center land to the lead lands when the part is
pushed into the solder paste.
15
15