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Recommended PCB routing guidelines for STM32F4xxxx devices
AN4488
42/50
AN4488 Rev 7
Figure 25. Via fan-out
Figure 26. FMC signal fan-out routing example
8.5.2
WLCSP143 0.4 mm pitch design example
06Y9
PP
PP
PP
PP
6XUIDFH/DQG3DG
PP
3DG
9LD
9LD'ULOO
3DGWRYLD
VSDFH
7UDFH
06Y9
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%
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(
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*
+
-
.
/
0
1
3
5
3:5
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Table 10. Wafer level chip scale package information
Package information (mm)
Design parameters (mm)
Bump pitch : 0.4
Microvia size : hole size
∅
= 0.1, via land: 0.2
Bump size : 0.25
Trace width/space : 0.07/0.05 or 0.07/0.07
Number of rows/columns : 13x11
Bump pad size
∅
= 0.26 max – 0.22 recommended
Non-solder mask defined via underbump
allowed
Solder mask opening bump
∅
=0.3 min (for 0.26
diameter pad)