User's Manual

SARA-R4 series - System Integration Manual
UBX-16029218 - R03 Design-in
Page 66 of 94
2.8 Reserved pins (RSVD)
SARA-R4 series modules have pins reserved for future use, marked as RSVD. All the RSVD pins are to be left
unconnected.
2.9 Module placement
An optimized placement allows a minimum RF line’s length and closer path from DC source for VCC.
Make sure that the module, analog parts and RF circuits are clearly separated from any possible source of
radiated energy. In particular, digital circuits can radiate digital frequency harmonics, which can produce Electro-
Magnetic Interference that affects the module, analog parts and RF circuits’ performance. Implement proper
countermeasures to avoid any possible Electro-Magnetic Compatibility issue.
Make sure that the module, RF and analog parts / circuits, and high speed digital circuits are clearly separated
from any sensitive part / circuit which may be affected by Electro-Magnetic Interference, or employ
countermeasures to avoid any possible Electro-Magnetic Compatibility issue.
Provide enough clearance between the module and any external part: clearance of at least 0.4 mm per side is
recommended to let suitable mounting of the parts.
The heat dissipation during continuous transmission at maximum power can significantly raise the
temperature of the application base-board below the SARA-R4 series modules: avoid placing temperature
sensitive devices close to the module.