Si590/591
10 Rev. 1.2
5. PCB Land Pattern: 5 x 7 mm, 6-pin
Figure 3 illustrates the 6-pin PCB land pattern for the 5 x 7 mm Si590/591. Table 12 lists the values for the
dimensions shown in the illustration.
Figure 3. Si590/591 PCB Land Pattern
Table 12. PCB Land Pattern Dimensions (mm)
Dimension (mm)
C1 4.20
E2.54
X1 1.55
Y1 1.95
Notes:
General
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing is per the ANSI Y14.5M-1994 specification.
3. This Land Pattern Design is based on the IPC-7351 guidelines.
4. All dimensions shown are at Maximum Material Condition (MMC). Least Material
Condition (LMC) is calculated based on a Fabrication Allowance of 0.05 mm.
Solder Mask Design
1. All metal pads are to be non-solder mask defined (NSMD). Clearance between
the solder mask and the metal pad is to be 60 µm minimum, all the way around
the pad.
Stencil Design
1. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls
should be used to assure good solder paste release.
2. The stencil thickness should be 0.125 mm (5 mils).
3. The ratio of stencil aperture to land pad size should be 1:1.
Card Assembly
1. A No-Clean, Type-3 solder paste is recommended.
2. The recommended card reflow profile is per the JEDEC/IPC J-STD-020
specification for Small Body Components.