SARA-R4/N4 series - System Integration Manual
UBX-16029218 - R11
Design-in
Page 113 of 157
2.9
Reserved pins (RSVD)
SARA-R4/N4 series modules have pins reserved for future use, marked as
RSVD
.
All the
RSVD
pins are to be left unconnected on the application board, except for the
RSVD
pin number
33
that can be externally connected to ground.
2.10
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
suitable 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.
Make sure that the module is placed in order to keep the antenna as far as possible from VCC supply line
and related parts (refer to
), from high speed digital lines (as USB) and from any possible noise
source.
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/N4 series modules: avoid placing
temperature sensitive devices close to the module.
