TOBY-L1 and MPCI-L1 series - System Integration Manual
UBX-13001482 - R04
Advance Information
Design-in
Page 43 of 90
Alternatively the L6924U, providing input voltage range up to 12 V, can charge from an AC wall adapter. When
a current-limited adapter is used, it can operate in quasi-pulse mode, reducing power dissipation.
C5
C8
GND
C7
C6
C9
TOBY-L1 series
71
VCC
72
VCC
70
VCC
+
USB
Supply
C3
R4
θ
U1
I
USB
I
AC
I
END
T
PRG
SD
V
IN
V
INSNS
MODE
ISEL
C2
C1
5V0
TH
GND
V
OUT
V
OSNS
V
REF
R1
R2
R3
Li-Ion/Li-Pol
Battery Pack
D1
B1
C4
Li-Ion/Li-Polymer
Battery Charger IC
D2
Figure 23: Li-Ion (or Li-Polymer) battery charging application circuit
Reference
Description
Part Number - Manufacturer
B1
Li-Ion (or Li-Polymer) battery pack with 470
Ω
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
Ω
T520D337M006ATE045 - KEMET
C7
100 nF Capacitor Ceramic X7R 0402 10% 16 V
GRM155R61A104KA01 - Murata
C8
56 pF Capacitor Ceramic C0G 0402 5% 25 V
GRM1555C1E560JA01 - Murata
C9
15 pF Capacitor Ceramic C0G 0402 5% 25 V
GRM1555C1E150JA01 - Murata
D1, D2
Low Capacitance ESD Protection
CG0402MLE-18G - Bourns
R1, R2
24 k
Ω
Resistor 0402 5% 0.1 W
RC0402JR-0724KL - Yageo Phycomp
R3
3.3 k
Ω
Resistor 0402 5% 0.1 W
RC0402JR-073K3L - Yageo Phycomp
R4
1.0 k
Ω
Resistor 0402 5% 0.1 W
RC0402JR-071K0L - Yageo Phycomp
U1
Single Cell Li-Ion (or Li-Polymer) Battery Charger IC
L6924U - STMicroelectronics
Table 14: Suggested components for Li-Ion (or Li-Polymer) battery charging application circuit
2.2.1.8
Guidelines for VCC or 3.3Vaux supply layout design
A good connection to the module’s
VCC
or
3.3Vaux
pins from the DC supply source is required for correct RF
performance. Guidelines are summarized in the following list:
•
All the available
VCC / 3.3Vaux
pins must be connected to the DC source
•
VCC / 3.3Vaux
connection must be as wide as possible and as short as possible
•
Any series component with Equivalent Series Resistance (ESR) greater than few milliohms must be avoided
•
VCC / 3.3Vaux
connection must be routed through a PCB area separated from sensitive analog signals and
sensitive functional units: it is good practice to interpose at least one layer of PCB ground between
VCC /
3.3Vaux
track and other signal routing
•
Coupling between
VCC / 3.3Vaux
and digital lines, especially USB must be avoided
•
The tank bypass capacitor with low ESR for current spikes smoothing described in section 2.2.1.6 should be
placed close to the
VCC / 3.3Vaux
pins. If the main DC source is a switching DC-DC converter, place the
large capacitor close to the DC-DC output and minimize the
VCC / 3.3Vaux
track length. Otherwise
consider using separate capacitors for DC-DC converter and TOBY-L1 / MPCI-L1 series module tank capacitor