LEA-M8S / LEA-M8T - Hardware Integration Manual
UBX-13003140 - R07
Production Information
Product handling
Page 24 of 31
•
When handling the RF pin, do not come into contact with any
charged capacitors and be careful when contacting materials that
can develop charges (e.g. patch antenna ~10 pF, coax cable ~50 –
80 pF/m, soldering iron, …)
•
To prevent electrostatic discharge through the RF input, do not
touch any exposed antenna area. If there is any risk that such
exposed antenna area is touched in non ESD protected work area,
implement proper ESD protection measures in the design.
•
When soldering RF connectors and patch antennas to the receiver’s
RF pin, make 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 16.
Small passive antennas
(<2 dBic and
performance critical)
Passive antennas
(>2 dBic or performance
sufficient)
Active antennas
A
RF
_IN
G
N
SS
Rec
ei
ver
LNA
B
L
RF
_IN
G
NS
S
Rec
ei
ver
C
D
RF
_IN
G
NS
S
Rec
ei
ver
LNA with appropriate ESD rating
Figure 16: 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.
