AN1902 Freescale Semiconductor / Motorola, AN1902 Datasheet - Page 14

• Manufacturer Part Number: AN1902
• Description: Quad Flat Pack No-Lead (QFN)
• Manufacturer: Freescale Semiconductor / Motorola

AN1902/D
14
4.2.2.2 PCB Land and Aperture Opening for 4x4 QFN
Figure 16 (L) Land Pattern on PCB, (R) Stencil Aperture Opening on 4x4mm QFN
Version
Lead pad width (mm)
Lead pad length (mm)
Pitch (mm)
Thermal pad width (mm)
Thermal pad length (mm
Aspect ratio
Area ratio
Freescale Semiconductor, Inc.
For More Information On This Product,
QFN
0.37mm
Quad Flat Pack No-Lead (QFN)
Thickness (T)
Go to: www.freescale.com
Table 5 Dimensions of Stencil Aperture
0.92mm
Aspect Ratio = W/T . . . . . . . . . . . ≥1.5
Area Ratio = LW/2T(L+W) . . . . . . ≥0.6
0.37
0.92
0.65
2.15
2.15
PCB Land
E
-
-
PCB land Pettern
4x4
Length (L)
0.37
0.92
0.65
2.15
2.15
S
-
-
PCB land
Aperture
opening
0.28
0.69
0.50
7.25
7.25
E
-
-
9x9
0.28
0.69
0.50
7.25
7.25
S
-
-
0.32mm
Width (W)
0.32
0.75
0.65
2.15
2.15
2.52
0.88
E
Stencil aperture
0.75mm
0.32
0.75
0.65
2.15
2.15
2.52
0.88
S
4x4
Stencil
0.28
0.69
0.50
7.25
7.25
2.20
0.78
MOTOROLA
E
0.28
0.69
0.50
7.25
7.25
2.20
0.78
9x9
S