LISA-U2 series - System integration manual
UBX-13001118 - R27
Design-In
Page 141 of 183
C1-Public
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-U2 module, according to the application board classification (see ETSI
EN 301 489-1
), to satisfy the requirements for the ESD immunity test summarized in
2.5.3.1
Antenna interface
The
ANT
pin of LISA-U2 modules provides ESD immunity up to 1000 V (contact and air discharge
according to IEC 61000-4-2): a higher protection level is required if the line is externally accessible on
the device (i.e. the application board where the LISA-U2 series module is mounted).
The following precautions are suggested for satisfying ESD immunity test requirements:
•
If the device implements an embedded antenna, the device insulating enclosure should provide
protection to direct contact discharge up to
±
4 kV and protection to air discharge up to
±
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
and protection to air discharge up to
±
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 and protection to air discharge up to
±
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
, as implemented in the EMC / ESD approved reference design of LISA-U2
series modules
☞
Antenna detection functionality is not provided when implementing the high pass filter described
in
as the ESD protection for the antenna port of LISA-U2 series modules.
External Antenna Enclosure
Application Board
LISA-U2 series
ANT
Radiating
Element
Zo = 50 Ohm
Antenna Cable
Antenna Port
Enclosure Port
C
L
Figure 68: Antenna port ESD immunity protection application circuit for LISA-U2 series modules
Reference
Description
Part Number - Manufacturer
C
15 pF Capacitor Ceramic C0G 0402 5% 50 V
GRM1555C1H150JA01 - Murata
L
39 nH Multilayer Chip Inductor L0G 0402 5%
LQG15HN39NJ02 - Murata
Table 53: Example of parts for the antenna port ESD immunity protection application circuit for LISA-U2 series modules
With LISA-U230 modules, the
ANT_DIV
pin provides ESD immunity up to
±
4 kV for direct Contact
Discharge and up to
±
8 kV for Air Discharge: no further precaution to ESD immunity test is needed, as
implemented in the EMC / ESD approved reference design of LISA-U230 modules.
