Active-Semi
FEATURES
Product Brief, 29-May-08
Advanced Information―All Information Subject to Change
ACT3780
ActivePath
TM
Battery Charger
GENERAL DESCRIPTION
The ACT3780 is a complete battery charging and
management solution for one cell Lithium-Ion or Lith-
ium-Polymer battery. The ACT3780 incorporates the
ActivePath
architecture which automatically selects
the best available input supply for the system.
When an external power source such as an AC
adapter or a USB port is connected in, the ACT3780
regulates the system voltage to 4.8V in addition to
providing charging current to the battery. If the exter-
nal input source is not present or the system load
current is more than the input source can provide,
the
ActivePath
supplies additional current from the
battery to the system.
The ACT3780 charger is a complete, thermally
regulated, stand-alone single cell linear Li+ charger
that integrates an internal power 12V MOSFET. The
battery regulation voltage is ±0.5% accurate, and is
factory programmed from 4.2V (other voltages avail-
able upon request).
The ACT3780 is available in an thermally enhanced
4mm x 4mm Thin-QFN and 3.5mm × 4.5mm Thin-
DFN 20-pin packages.
•
ActivePath
TM
System Power Selection of Best
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Available Input Supply
40mΩ Battery Switch for Highest Efficiency
Dynamic Control of Charging Current Allowing
System to Draw Maximum Load from AC/USB
Input
±0.5% Battery Voltage Accuracy
Up to 12V Input
Thermal Regulation for Charge Control
Charge Status Outputs for LED or System
Interface
Battery Voltage Level Indication
Programmable Fast Charge Current
Programmable Charging Timer
Low Reverse Leakage Current
Short-Circuit and Thermal Protection
Preconditioning for Deeply Depleted Battery
Low Quiescent Current Standby Mode
Space-Saving, Thermally-Enhanced TQFN44-20
or TDFN3545-20 Packages
APPLICATIONS
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Personal Navigation Devices
Smart Mobile Phones
Blue-Tooth Devices
Portable Media Players
Portable Devices
SIMPLIFIED APPLICATION CIRCUIT
AC Adapter/USB
CHG_IN
SYS
Li-ion Battery
+
ISET
BAT
STAT1
STAT2
To SYSTEM
Pb
Pb-free
ACT3780
Active
Path
TM
Innovative Power
TM
ActivePath
TM
-1-
www.active-semi.com
Copyright © 2008 Active-Semi, Inc.
is a trademark of Active-Semi.
ACTIVE-SEMI [ ACTIVE-SEMI, INC ]
