LISA-U2 series - System Integration Manual
UBX-13001118 - R19
Early Production Information
Design-In
Page 138 of 175
With LISA-U230 modules, the
ANT_DIV
pin provides ESD immunity up to +4 kV / -4 kV for direct Contact
Discharge and up to +8 kV / -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.
RESET_N pin
The following precautions are suggested for the
RESET_N
line of LISA-U2 modules, depending on the
application board handling, to satisfy ESD immunity test requirements:
A 47 pF bypass capacitor (e.g. Murata GRM1555C1H470JA01) must 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 enclosure
A proper series chip ferrite bead noise/EMI suppression filter (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 enclosure
A 220 nF bypass capacitor (e.g. Murata GRM155R60J224KE01) must be mounted as close as possible to the
RESET_N
pin of LISA-U2 series modules to avoid a module reset caused by an electrostatic discharge applied
to the application board enclosure
It is recommended to keep the connection line to
RESET_N
as short as possible
Maximum ESD sensitivity rating of the
RESET_N
pin is 1 kV (Human Body Model according to JESD22-A114F).
Higher protection level could be required if the
RESET_N
pin is externally accessible on the application board.
The following precautions are suggested to achieve higher protection level:
A general purpose ESD protection device (e.g. EPCOS CA05P4S14THSG varistor array or EPCOS
CT0402S14AHSG varistor) should be mounted on the
RESET_N
line, close to accessible point
The
RESET_N
application circuit implemented in the EMC / ESD approved reference designs of LISA-U2 series
moduels is described in Figure 20 and Table 19 (section 1.6.3).
SIM interface
The following precautions are suggested for LISA-U2 modules SIM interface (
VSIM
,
SIM_RST
,
SIM_IO
,
SIM_CLK
pins), depending on the application board handling, to satisfy ESD immunity test requirements:
A 47 pF bypass capacitor (e.g. Murata GRM1555C1H470J) must be mounted on the lines connected to
VSIM
,
SIM_RST
,
SIM_IO
and
SIM_CLK
pins to assure SIM interface functionality when an electrostatic
discharge is applied to the application board enclosure
It is suggested to use as short as possible connection lines at SIM pins
Maximum ESD sensitivity rating of SIM interface pins is 1 kV (Human Body Model according to JESD22-A114F).
Higher protection level could be required if SIM interface pins are externally accessible on the application board.
The following precautions are suggested to achieve higher protection level:
A low capacitance (i.e. less than 10 pF) ESD protection device (e.g. Infineon ESD8V0L2B-03L or AVX
USB0002) should be mounted on each SIM interface line, close to accessible points (i.e. close to the SIM
card holder)
The SIM interface application circuit implemented in the EMC / ESD approved reference designs of LISA-U2 series
modules versions is described in the section 1.8.1.
Other pins and interfaces
All the module pins that are externally accessible on the device integrating LISA-U2 module should be included in
the ESD immunity test since they are considered to be a port as defined in
ETSI EN 301 489-1
[12]. Depending
on applicability, to satisfy ESD immunity test requirements according to ESD category level, all the module pins
that are externally accessible should be protected up to +4 kV / -4 kV for direct Contact Discharge and up to
+8 kV / -8 kV for Air Discharge applied to the enclosure surface.
