mc34671aep/r2 Freescale Semiconductor, Inc, mc34671aep/r2 Datasheet - Page 17

• Manufacturer Part Number: mc34671aep/r2
• Description: Mc34671 600ma High-input Voltage Charger For Single-cell Li-ion And Li-polymer Batteries
• Manufacturer: Freescale Semiconductor, Inc

INPUT CAPACITOR
transient that may cause instability. A 1.0µF, X5R, 16V-rated
ceramic capacitor is recommended for most applications.
OUTPUT CAPACITOR
minimum 2.2µF nominal value is recommended at the output.
Depending on the load transient current, larger capacitance
may be required.
CC-MODE CURRENT SETTING
resistor, R
guarantee 5% a current accuracy.
STAND-ALONE CHARGER
without MCUs.
Analog Integrated Circuit Device Data
Freescale Semiconductor
The input capacitor is used to reduce the input voltage
For stable operation, an X5R ceramic capacitor with a
The CC-mode current can be programmed by the external
The MC34671 can be used in a stand-alone charger
ISET
. A 1% accuracy resistor is recommended to
Input
Figure 23
shows such an application. The
GREEN
470
470
RED
Figure 23. Standalone Li+ Battery Charger
TYPICAL APPLICATIONS
1µF
INTRODUCTION
APPLICATIONS
VIN
GND
CHG
PPR
EN
MC34671
DROPOUT VOLTAGE
programmed CC-mode charge current due to the voltage
dropout over the power MOSFET. The worst-case of the
R
higher than V
programmed CC-mode current.
THERMAL CONSIDERATIONS
enhanced UDFN package. A careful thermal design must be
considered. The exposed pad needs to be well soldered to a
large copper ground plane on the component layer. If the
component layer is space limited and does not allow for a
large copper plane, the thermal pad must be connected to
other ground layers through a via array. This allows
MC34671 to charge the battery with the maximum current,
while minimizing the die temperature.
green LED indicates the power presence and the red LED
indicates the charge status. In total, only 7 external
components are required.
DS(ON)
If the DC input voltage is too low, it may not maintain the
The MC34671 is available in a tiny 2x3 thermally-
is 700mΩ. The input voltage should be at least
FAST
ISET
BAT
BAT
+ I
5.23k
CHG
x 700mΩ to guarantee the
2.2µF
TYPICAL APPLICATIONS
Li+
INTRODUCTION
34671
17