User's Manual

SARA-G3 and SARA-U2 series - System Integration Manual
UBX-13000995 - R08 Objective Specification Design-in
Page 143 of 188
2.13 ESD guidelines
The sections 2.13.1 and 2.13.2 are related to EMC / ESD immunity, herein described in section 2.13.1. The
modules are ESD sensitive devices and the ESD sensitivity for each pin (as Human Body Model according to
JESD22-A114F) is specified in SARA-G3 series Data Sheet [1] or SARA-U2 series Data Sheet [2], requiring special
precautions when handling: for ESD handling guidelines see section 3.2.
2.13.1 ESD immunity test overview
The immunity of devices integrating SARA-G3 and SARA-U2 series modules to Electro-Static Discharge (ESD) is
part of the Electro-Magnetic Compatibility (EMC) conformity, which is required for products bearing the CE
marking, compliant with the R&TTE Directive (99/5/EC), the EMC Directive (89/336/EEC) and the Low Voltage
Directive (73/23/EEC) issued by the Commission of the European Community.
Compliance with these directives implies conformity to the following European Norms for device ESD immunity:
ESD testing standard CENELEC EN 61000-4-2 [18] and the radio equipment standards ETSI EN 301 489-1 [19],
ETSI EN 301 489-7 [20], ETSI EN 301 489-24 [21], which requirements are summarized in Table 47.
The ESD immunity test is performed at the enclosure port, defined by ETSI EN 301 489-1 [19] as the physical
boundary through which the electromagnetic field radiates. If the device implements an integral antenna, the
enclosure port is defined as all insulating and conductive surfaces housing the device. If the device implements a
removable antenna, the antenna port can be separated from the enclosure port. The antenna port includes the
antenna element and its interconnecting cable surfaces.
The applicability of the ESD immunity test to the whole device depends on the device classification as defined by
ETSI EN 301 489-1 [19]. Applicability of the ESD immunity test to the relative device ports or the relative
interconnecting cables to auxiliary equipments, depends on device accessible interfaces and manufacturer
requirements, as defined by ETSI EN 301 489-1 [19].
Contact discharges are performed at conductive surfaces, while air discharges are performed at insulating
surfaces. Indirect contact discharges are performed on the measurement setup horizontal and vertical coupling
planes as defined in CENELEC EN 61000-4-2 [18].
For the definition of integral antenna, removable antenna, antenna port, device classification see ETSI EN
301 489-1 [19], whereas for contact and air discharges definitions see CENELEC EN 61000-4-2 [18]
Application
Category
Immunity Level
All exposed surfaces of the radio equipment and ancillary equipment in a
representative configuration
Contact Discharge
4 kV
Air Discharge
8 kV
Table 47: EMC / ESD immunity requirements as defined by CENELEC EN 61000-4-2, ETSI EN 301 489-1, 301 489-7, 301 489-24
2.13.2 ESD immunity test of u-blox SARA-G3 and SARA-U2 reference designs
EMC certification tests (including ESD immunity) have been successfully performed on the u-blox SARA-G3 and
SARA-U2 reference designs according to applicable European Norms (see Table 47), as required for customized
devices integrating the modules for R&TTED and European Conformance CE mark.
The EMC / ESD approved u-blox reference designs consist of a SARA-G3 or a SARA-U2 module soldered onto a
motherboard which provides supply interface, SIM card, headset and communication port. An external cellular
antenna is connected to an SMA connector provided on the motherboard.
Since an external antenna is used, the antenna port can be separated from the enclosure port. The reference
design is not enclosed in a box so that the enclosure port is not indentified with physical surfaces. Therefore,
some test cases cannot be applied. Only the antenna port is identified as accessible for direct ESD exposure.