EFM8BB2 Datasheet, PDF (50/55 Pages) Silicon Laboratories – The EFM8BB2 highlighted features are listed below

9.2 QFN20 PCB Land Pattern
EFM8BB2 Data Sheet
QFN20 Package Specifications
Dimension
C1
C2
C3
C4
E
X1
X2
X3
Y1
Y2
Y3
Figure 9.2. QFN20 PCB Land Pattern Drawing
Table 9.2. QFN20 PCB Land Pattern Dimensions
Min
Max
3.10
3.10
2.50
2.50
0.50
0.30
0.25
0.35
1.80
0.90
0.25
0.35
1.80
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