LISA-U series - System Integration Manual
UBX-13001118 - R17
Advance information
Design-In
Page 148 of 190
2.5.3
ESD application circuits
The application circuits described in this section are recommended and should be implemented in any device
that integrates a LISA-U module, according to the application board classification (see
ETSI EN 301 489-1
to satisfy the requirements for ESD immunity test summarized in Table 54.
Antenna interface
With LISA-U1 series modules, the
ANT
pin provides ESD immunity up to 500 V (contact and air discharge
according to IEC 61000-4-2): higher protection level is required if the line is externally accessible on the device
(i.e. the application board where LISA-U1 series module is mounted).
The following precautions are suggested to satisfy ESD immunity test requirements using LISA-U1 series
modules:
If the device implements an embedded antenna, the insulating enclosure of the device should provide
protection to direct contact discharge up to +4 kV / -4 kV and protection to air discharge up to +8 kV / -8 kV
to the antenna interface
If the device implements an external antenna, the antenna and its connecting cable should provide a
completely insulated enclosure able to provide protection to direct contact discharge up to +4 kV / -4 kV and
protection to air discharge up to +8 kV / -8 kV to the whole antenna and cable surfaces, as implemented in
the EMC / ESD approved reference design of LISA-U1 series modules
With the LISA-U2 series moduels, the
ANT
pin provides ESD immunity up to 1000 V (contact and air discharge
according to IEC 61000-4-2): higher protection level is required if the line is externally accessible on the device
(i.e. the application board where LISA-U2 series module is mounted).
The following precautions are suggested for satisfying ESD immunity test requirements using LISA-U2 series
modules:
If the device implements an embedded antenna, the device insulating enclosure should provide protection to
direct contact discharge up to +4 kV / -4 kV and protection to air discharge up to +8 kV / -8 kV to the
antenna interface
If the device implements an external antenna, the antenna and its connecting cable should provide a
completely insulated enclosure able to provide protection to direct contact discharge up to +4 kV / -4 kV and
protection to air discharge up to +8 kV / -8 kV to the whole antenna and cable surfaces
If the device implements an external antenna and the antenna and its connecting cable do not provide a
completely insulated enclosure able to provide protection to direct contact discharge up to +4 kV / -4 kV and
protection to air discharge up to +8 kV / -8 kV to the whole antenna and cable surfaces, an external high
pass filter, consisting of a series 15 pF capacitor (Murata GRM1555C1H150JA01) and a shunt 39 nH coil
(Murata LQG15HN39NJ02) should be implemented at the antenna port as described in Figure 82, as
implemented in the EMC / ESD approved reference design LISA-U2 series modules
Antenna detection functionality is not provided when implementing the high pass filter described in
Figure 82 and Table 56, as ESD protection for the antenna port of LISA-U2 series modules.
