Recommendations on PCB assembly LBP01
6/8 Doc ID 022950 Rev 1
4 Recommendations on PCB assembly
4.1 PCB design
1. To control the solder paste amount, the closed via is recommended instead of open
vias.
2. The position of tracks and open vias in the solder area should be well balanced. The
symmetrical layout is recommended, in case any tilt phenomena caused by
asymmetrical solder paste amount due to the solder flow away.
Figure 9. Printed circuit board layout
4.2 Reflow profile
Figure 10. ST ECOPACK
®
recommended soldering reflow profile for PCB mounting
Note: Minimize air convection currents in the reflow oven to avoid component movement.
60 sec
(90 max)
250
0
50
100
150
200
240210180150120906030 300
270
-2 °C/s to
-3 °C/s
-6 °C/s max
240-245 °C
2 - 3 °C/s
0.9 °C/s
Temperature (°C)
Time (s)