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NEO-M8L - Hardware integration manual
UBX-16010549 - R08
Product handling
Page 20 of 28
C1-Public
When soldering RF connectors and patch antennas to the
receiver’s RF pin, be sure to use an ESD-safe soldering iron (tip).
⚠
Failure to observe these precautions can result in severe damage to the GNSS module!
ESD protection measures
⚠
GNSS positioning modules are sensitive to Electrostatic Discharge (ESD). Special precautions are
required when handling.
☞
For more robust designs, employ additional ESD protection measures. Using an LNA with
appropriate ESD rating can provide enhanced GNSS performance with passive antennas and
increases ESD protection.
Most defects caused by ESD can be prevented by following strict ESD protection rules for production
and handling. When implementing passive antenna patches or external antenna connection points,
then additional ESD measures can also avoid failures in the field as shown in Figure 13.
Small passive antennas (<2 dBic and
performance critical)
Passive antennas (>2 dBic or
performance sufficient)
Active antennas
A
RF
_
IN
G
N
S
S
R
ec
ei
ve
r
LNA
B
L
RF
_
IN
G
N
S
S
R
e
c
e
iv
e
r
C
D
RF
_
IN
G
N
S
S
R
e
c
e
iv
e
r
LNA with appropriate ESD rating
Figure 13: ESD precautions
☞
Protection measure A is preferred because it offers the best GNSS performance and best level of
ESD protection.
Electrical Overstress (EOS)
Electrical Overstress (EOS) usually describes situations when the maximum input power exceeds the
maximum specified ratings. EOS failure can happen if RF emitters are close to a GNSS receiver or its
antenna. EOS causes damage to the chip structures. If the RF_IN is damaged by EOS, it is hard to
determine whether the chip structures have been damaged by ESD or EOS.
EOS protection measures
☞
For designs with GNSS positioning modules and wireless (e.g. GSM/GPRS) transceivers in close
proximity, ensure sufficient isolation between the wireless and GNSS antennas. If wireless power
output causes the specified maximum power input at the GNSS RF_IN to be exceeded, employ
EOS protection measures to prevent overstress damage.
For robustness, EOS protection measures as shown in Figure 14 are recommended for designs
combining wireless communication transceivers (e.g. GSM, GPRS) and GNSS in the same design or in
close proximity.
