si4704 Silicon Laboratories, si4704 Datasheet - Page 32

• Manufacturer Part Number: si4704
• Description: Broadcast Fm Radio Receiver For Consumer Electronics
• Manufacturer: Silicon Laboratories

Si4704/05-C40
32
Notes: General
Notes: Solder Mask Design
Notes: Stencil Design
Notes: Card Assembly
Symbol
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 IPC-SM-782 guidelines.
4. All dimensions shown are at Maximum Material Condition (MMC). Least Material
1. All metal pads are to be non-solder mask defined (NSMD). Clearance between the
1. A stainless steel, laser-cut, and electro-polished stencil with trapezoidal walls should
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 the perimeter pads.
4. A 1.45 x 1.45 mm square aperture should be used for the center pad. This provides
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
GD
D2
E2
D
E
e
f
Condition (LMC) is calculated based on a Fabrication Allowance of 0.05 mm.
solder mask and the metal pad is to be 60 µm minimum, all the way around the pad.
be used to assure good solder paste release.
approximately 70% solder paste coverage on the pad, which is optimum to assure
correct component stand-off.
for Small Body Components.
1.60
1.60
2.10
Min
Table 16. PCB Land Pattern Dimensions
Millimeters
2.71 REF
0.50 BSC
2.71 REF
2.53 BSC
Max
1.80
1.80
—
Rev. 1.0
Symbol
GE
ZD
ZE
W
X
Y
2.10
Min
—
—
—
—
Millimeters
0.61 REF
Max
0.34
0.28
3.31
3.31
—