Integration Manual

Table Of Contents
LISA-U2 series - System Integration Manual
UBX-13001118 - R25 Design-In Page 141 of 182
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 [12]), to satisfy the requirements for the ESD immunity test summarized in Table 51.
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 Figure 68, 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 Figure 68 and Table 53 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.