SI53311 Datasheet, PDF (27/30 Pages) Silicon Laboratories – 1:6 LOW JITTER UNIVERSAL BUFFER/LEVEL TRANSLATOR WITH 2:1 INPUT MUX

6. PCB Land Pattern
6.1. 5x5 mm 32-QFN Package Land Pattern
Si53311
Figure 13. Si53311 5x5 mm 32-QFN Package Land Pattern
Table 22. PCB Land Pattern
Dimension
Min
Max
Dimension
Min
Max
C1
4.52
4.62
X2
2.20
2.30
C2
4.52
4.62
E
0.50 BSC
X1
0.20
0.30
Y1
0.59
0.69
Y2
2.20
2.30
Notes:
General
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. This Land Pattern Design is based on the IPC-7351 guidelines.
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 m 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 for all perimeter pads.
4. A 2x2 array of 0.75 mm square openings on 1.15 mm pitch should be used for the center ground pad.
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.
Preliminary Rev. 0.4
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