LISA-C2 series and FW75-C200 - System Integration Manual
UBX-13000620 - R21
Early Production Information
System description
Page 18 of 103
•
Maximum pulse and DC discharge current
: the non-rechargeable battery with its output circuit must be
capable of delivering 1.2 A to the
VCC
pins and must be capable of delivering a DC current greater than the
module maximum average current consumption at the
VCC
pins. The maximum pulse and the maximum DC
discharge current is not always reported in battery data sheets, but the maximum DC discharge current is
typically almost equal to the battery capacity in Amp-hours divided by 1 hour.
•
DC series resistance
: the non-rechargeable battery with its output circuit must be capable of avoiding a
VCC voltage drop greater than 250 mV during peak currents (Max Tx Power).
1.5.3.5
Additional recommendations for the VCC supply application circuits
To reduce voltage drops, use a low impedance power source. The resistance of the power supply lines
(connected to the
VCC
and
GND
pins of the module) on the application board and battery pack should also be
considered and minimized: cabling and routing must be as short as possible in order to minimize power losses.
Three
or five
pins are allocated for
VCC
supply. Another seven pins are designated for
GND
connection. Even if
all the
VCC
pins and all the
GND
pins are internally connected within the module, it is recommended to properly
connect all of them to supply the module in order to minimize series resistance losses.
The placement of ceramic capacitors on the
VCC
line on the main board close to the connector will benefit
operation.
To reduce voltage ripple and noise, place the following capacitors near the
VCC
pins:
•
100 nF capacitor (e.g. Murata GRM155R61A104K) to filter digital logic noise from clocks and data sources
•
22 µF capacitor (e.g. Murata GRM31CR60J226K) to supply local DC energy
Figure 6 shows the complete configuration but the mounting of each single component depends on the
application design.
3.6V
C1
GND
C2
u-blox C200
VCC
VCC
VCC
+
VCC
VCC
LISA-C200
FW75
Figure 6: Suggested schematic design to reduce voltage ripple and noise and to avoid undershoot/ overshoot on voltage drops
Reference
Description
Part Number - Manufacturer
C1
22 µF Capacitor Ceramic 6.3 V 45
GRM31CR60J226K - Murata
C2
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R61A104KA01 - Murata
Table 8: Suggested components to reduce voltage ripple and noise and to avoid undershoot/ overshoot on voltage drops
3
LISA-C200.
4
FW75.
