LISA-U2 series - System integration manual
UBX-13001118 - R27
System description
Page 26 of 183
C1-Public
To reduce voltage ripple and noise, which should improve RF performance if the application device
integrates an internal antenna, place the following series ferrite bead and bypass capacitors near the
VCC
pins of the module:
•
Ferrite bead for GHz band noise (e.g. Murata BLM18EG221SN1) as close as possible to the
VCC
pins of the module, implementing the circuit described in
, to filter EMI in all the GSM /
UMTS bands.
•
68 pF capacitor with Self-Resonant Frequency in the 800/900 MHz range (e.g. Murata
GRM1555C1H680J) at the
VCC
line where it narrows close to the module (see
), to filter
EMI in lower bands
•
15 pF capacitor with Self-Resonant Frequency in 1800/1900 MHz range (e.g. Murata
GRM1555C1H150J) at the
VCC
line where it narrows close to the module (see
), to filter
EMI in higher bands
•
10 nF capacitor (e.g. Murata GRM155R71C103K) to filter digital logic noise from clocks and data
sources
•
100 nF capacitor (e.g. Murata GRM155R61A104K) to filter digital logic noise from clocks and data
sources
☞
shows the complete configuration, but keep in mind that the mounting of each single
component depends on the application design. It is highly recommended to provide the series
ferrite bead and all the
VCC
bypass capacitors as described in
application device integrates an internal antenna.
C1
GND
C2
C4
LISA-U2 series
62
VCC
63
VCC
61
VCC
3V8
C5
+
LISA-U
series
C5
GND plane
VCC line
Capacitor with
SRF ~900 MHz
FB1
C1
C3 C4
FB1
Ferrite Bead
for GHz noise
C2
C3
Capacitor with
SRF ~1900 MHz
Figure 9: Suggested schematic and layout design for the VCC line; highly recommended when using an integrated antenna
Reference
Description
Part Number - Manufacturer
C1
68 pF Capacitor Ceramic C0G 0402 5% 50 V
GRM1555C1H680JA01 - Murata
C2
15 pF Capacitor Ceramic C0G 0402 5% 50 V
GRM1555C1H150JA01 - Murata
C3
10 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R71C103KA01 - Murata
C4
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R71C104KA01 - Murata
C5
330 µF Capacitor Tantalum D_SIZE 6.3 V 45 m
T520D337M006ATE045 - KEMET
FB1
Chip Ferrite Bead EMI Filter for GHz Band Noise
220
at 100 MHz, 260
at 1 GHz, 2000 mA
BLM18EG221SN1 - Murata
Table 10: Suggested parts
for VCC circuit close to module’ pins; highly recommende
d when using an integrated antenna
External battery charging application circuit
LISA-U2 series modules do not have an on-board charging circuit. An example of a battery charger
design, suitable for applications that are battery powered with a Li-Ion (or Li-Polymer) cell, is provided
in
In the application circuit, a rechargeable Li-Ion (or Li-Polymer) battery cell, that features proper pulse
and DC discharge current capabilities and proper DC series resistance, is directly connected to the