AMY-6M - Hardware Integration Manual
UBX-17021971 – R07
Design-in
Page 34 of 57
2.12
Layout
This section provides important information for designing a reliable and sensitive GPS system.
GPS signals at the surface of the Earth are about 15dB below the thermal noise floor. Signal loss at the antenna
and the RF connection must be minimized as much as possible. When defining a GPS receiver layout, the
placement of the antenna with respect to the receiver, as well as grounding, shielding and jamming from other
digital devices are crucial issues and need to be considered very carefully.
2.12.1
Footprint
Figure 28: Recommended footprint (top view)
Units in are in mm.
2.12.2
Paste mask
The paste mask
shall be 50µm smaller than the copper pads with a paste thickness of 100µm.
The paste mask outline needs to be considered when defining the minimal distance to the next component.
These are recommendations only and not specifications. The exact geometry, distances, stencil thicknesses
and solder paste volumes must be adapted to the specific production processes (e.g. soldering etc.) of the
customer.
2.12.3
Placement
A very important factor in achieving maximum GPS performance is the placement of the receiver on the PCB.
The connection to the antenna must be as short as possible to avoid jamming into the very sensitive RF section.
Make sure that RF critical circuits are clearly separated from any other digital circuits on the system board. To
achieve this, position the receiver digital part towards your digital section of the system PCB. Care must also be