C8051F980-C-GM Datasheet, PDF (45/325 Pages) Silicon Laboratories – Ultra Low Power, 8-2 kB Flash, Capacitive Sensing MCU

C8051F99x-C8051F98x
Table 3.5. PCB Land Pattern
Dimension
C1
C2
E
X1
X2
Y1
Y2
Notes:
MIN
MAX
3.90
4.00
3.90
4.00
0.50 BSC
0.20
0.30
2.70
2.80
0.65
0.75
2.70
2.80
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 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 for all
perimeter pads.
4. A 2x2 array of 1.10 mm x 1.10 mm openings on 1.30 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.
Rev. 1.2
45