Layout recommendation
UM2231
20/26
UM2231 Rev 6
Figure 15. Layout proposal
As GNSS signals are very low, it is important to take care of the layout. There are
2 main recommendations to follow for Teseo-LIV3 layout.
1.
Many ground vias have to be placed around the RF ground (Pin10 and 12) to increase
ground size.
2. In addition, it is important to have an isolation of the power ground (Pin1).
Don’t connect it directly to ground. One or two vias from Top (assuming Teseo-LIV3 is
on Top) to Bottom (without any ground connection) and then a second via from Bottom
to GND plane can be used without any connection on top, as shown in
Figure 16
.
Figure 16. Pin1 gnd “isolation” example
It is important to have 50 ohms RF traces width as close as possible to components pads
size to avoid too much impedance jumps.
When possible, avoid any trace below Teseo-LIV3 module.
