MAX-M10S - Integration manual
The RF section should not be subject to noisy digital supply currents running through its GND plane.
Make sure that critical RF circuits are clearly separated from any other digital circuits on the system
board. To achieve this, position the receiver digital part towards the digital section of the system
PCB and place the RF section and antenna as far away as possible from the other digital circuits on
the board. Keep at least a 5 mm distance to any RF component and ensure proper grounding.
For applications using cellular antennas, increase the distance between both antennas as
much as possible.
Another very important factor in GNSS applications is the grounding concept. Ensure good ground
reference to the host ground by increasing the number of GND vias. The GND vias will improve the
GND reference between all the layers, and the pads will serve as thermal relief.
Any stubs at the ground planes must be avoided or ended with a via to the reference ground.
Otherwise, they could pick up and propagate interference.
Figure 28: GND stub ended with a via
It is recommended to ground the area below the module, on the top and second layer. Avoid signal
lines crossing below the module at these two layers.
For the RF signal line, it is best to use the co-planar waveguide with ground on the second layer. All
the RF parts need a solid GND plane underneath in order to achieve the targeted impedance in the
RF signal line.
The length and geometry in the RF signal line must be carefully analyzed. The impedance of the RF
signal line must be 50 Ω. Select accordingly the stack-up, copper, and dielectric properties of the
PCB to fulfill this condition. The RF signal line should be as short as possible and the ground plane
around should be filled with GND vias.
Care must also be exercised with placing the receiver in proximity to circuitry that can emit heat.
Temperature-sensitive components inside the module, like TCXOs and crystals, are sensitive to
sudden changes in ambient temperature which can adversely impact satellite signal tracking.
Sources can include co-located power devices, cooling fans or thermal conduction via the PCB.
The GND planes can conduct heat to other elements, but they can act as heat dissipators as well.
Increasing the number of GND vias helps to decrease sudden temperature changes.
High temperature drift and air vents can affect the GNSS performance. For best
performance, avoid high temperature drift and air vents near the module.
3.4.1 Package footprint, copper and solder mask
shows the dimensions of the MAX-M10S form factor.
UBX-20053088 - R03
3 Hardware integration
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