LENA-R8 series - System integration manual
UBX-22015376 - R02
Design-in
Page 40 of 116
C1-Public
Reference
Description
Part number - manufacturer
B1
Li-ion (or Li-Polymer) battery pack with 470
NTC Various manufacturer
C1, C4
1 µF Capacitor Ceramic X7R 0603 10% 16 V
GRM188R71C105KA12 - Murata
C2, C6
10 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R71C103KA01 - Murata
C3
1 nF Capacitor Ceramic X7R 0402 10% 50 V
GRM155R71H102KA01 - Murata
C5
330 µF Capacitor Tantalum D_SIZE 6.3 V 45 m
T520D337M006ATE045 - KEMET
C7
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R61A104KA01 - Murata
C8
68 pF Capacitor Ceramic C0G 0402 5% 50 V
GRM1555C1H680JA01 - Murata
C9
15 pF Capacitor Ceramic C0G 0402 5% 25 V
GRM1555C1E150JA01 - Murata
C10
8.2 pF Capacitor Ceramic C0G 0402 5% 50 V
GRM1555C1H8R2DZ01 - Murata
D1, D2
Low Capacitance ESD Protection
CG0402MLE-18G - Bourns
R1, R2
24 k
Resistor 0402 5% 0.1 W
Various manufacturers
R3
3.3 k
Resistor 0402 5% 0.1 W
Various manufacturers
R4
1.0 k
Resistor 0402 5% 0.1 W
Various manufacturers
U1
Single Cell Li-ion (or Li-Polymer) Battery Charger IC
for USB port and AC Adapter
L6924U - STMicroelectronics
Table 12: Suggested components for a Li-ion (or Li-Polymer) battery charging application circuit
☞
, and in particular
, for the parts recommended to be
provided if the application device integrates an internal antenna.
2.2.1.7
Guidelines for external charging and power path management circuit
Application devices where both a permanent primary supply / charging source (e.g., ~12 V) and a
rechargeable back-up battery (e.g., 3.7 V Li-Pol) are available at the same time as the possible supply
source should implement a suitable charger / regulator with an integrated power path management
function to supply the module and the whole device while simultaneously and independently charging
the battery.
illustrates a simplified block diagram circuit showing the working principle of a
charger / regulator with integrated power path management function. This component allows the
system to be powered by a permanent primary supply source (e.g., ~12 V) using the integrated
regulator which simultaneously and independently recharges the battery (e.g., 3.7 V Li-Pol) that
represents the back-up supply source of the system: the power path management feature permits
the battery to supplement the system current requirements when the primary supply source is not
available or cannot deliver the peak system currents.
A power management IC should meet the following prerequisites to comply with the module
VCC
requirements summarized in
•
High efficiency internal step-down converter, compliant with the performances specified in
section
•
Low internal resistance in the active path Vout
–
Vbat, typically lower than 50 m
•
High efficiency switch mode charger with separate power path control
