User's Manual

LISA-U1/LISA-H1 series - System Integration Manual
3G.G2-HW-10002-2 Advance Information Design-In
Page 102 of 116
2.5 ESD immunity test precautions
The immunity to the EMS phenomenon Electrostatic Discharge of the device (i.e. the application board where
the LISA-U1/LISA-H1 series module is mounted) must be certified complying the testing requirements standard
[10] and the requirements for radio and digital cellular radio telecommunications system equipments standards
[11] [12].
The ESD test is performed at the enclosure port [11] referred as the physical boundary through which EM field
radiates. If the device implements an integral antenna [11] the enclosure is intended as all insulating surfaces
housing the device. If the device implements a removable antenna [11] the enclosure port is limited to the
antenna port [11] hence the enclosure port comprises the antenna element and its interconnecting cable
surfaces.
The applicability of the ESD test depends to the device classification [11], as well the test on other ports [11] or
on interconnecting cables to auxiliary equipments depends to the device accessible interfaces and manufacturer
requirements.
Contact discharges [10] are performed at conductive surfaces whereas air discharges [10] are performed at
insulating surfaces. Indirect contact discharges are performed on the measurement setup horizontal and vertical
coupling planes [10].
Some precautions should be implemented as described in the following sections in order to satisfy ESD immunity
test requirements [10] [11] [12] performed at device enclosure complying the category level [11] and shown in
the following table.
Category
Immunity Level
Contact Discharge to coupling planes (indirect contact discharge)
+2 kV / -2 kV
+4 kV / -4 kV
Contact Discharges to conducted surfaces (direct contact discharge)
Not Applicable
2
*
Air Discharge at insulating surfaces
+2 kV / -2 kV
+4 kV / -4 kV
+8 kV / -8 kV
Table 37: Enclosure ESD immunity level, standards “EN 61000-4-2, EN 301 489-1 V1.8.1, EN 301 489-7 V1.3.1”
2.5.1 General precautions
The following module interfaces could be involved in the ESD immunity test criticality depending on the
application board handling. Some precautions are herein suggested.
Sensitive interface is the reset line (RESET_N pin):
 A 47 pF bypass capacitor (e.g. Murata GRM1555C1H470JA01) have to be mounted on the line termination
connected to the RESET_N pin to avoid a module reset caused by an electrostatic discharge applied to the
application board
 A series ferrite bead (e.g. Murata BLM15HD182SN1) must be added on the line connected to the RESET_N
pin to avoid a module reset caused by an electrostatic discharge applied to the application board
2
LISA mounted on application reference design:
Applicability -> EUT with insulating surfaces, air discharges on interconnecting cables between EUT and antenna and auxiliary equipments
Not Applicability -> EUT with conductive surface, direct contact discharge