USB Port/AC Adapter
Lithium-Ion/Polymer Battery Charger
General Description
The AAT3686 BatteryManager is a highly integrated
single-cell lithium-ion/polymer battery charger IC
designed to operate with USB port and AC adapter
inputs. It requires the minimum number of external
components.
The AAT3686 precisely regulates battery charge
voltage and current for 4.2V lithium-ion/polymer
battery cells. Adapter charge current rates can be
programmed up to 1.5A. In the absence of an
adapter and with a USB port connected, the battery
can also be charged by USB power. Depending on
the USB port type, the AAT3686 charge current can
be programmed for two separate levels up to
500mA. An optional Charge Reduction Loop is also
built in to allow users to charge the battery with
available current from a USB port, while keeping
the port voltage regulated. USB charging is dis-
abled when an adapter is present.
Battery temperature and charge state are fully moni-
tored for fault conditions. In the event of an over-volt-
age or over-temperature failure, the device will auto-
matically shut down, thus protecting the charging
device, control system, and the battery under charge.
Status monitor output pins are provided to indicate
the battery charge status by directly driving two exter-
nal LEDs. A serial interface output is available to
report 22 various status states to a microcontroller.
The AAT3686 is available in a Pb-free, thermally-
enhanced, space-saving TDFN34-16 (3x4mm) or
TDFN44-16 (4x4mm) package and is rated over the
-40°C to +85°C temperature range.
AAT3686
Features
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BatteryManager
™
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USB Port/AC Adapter System Power Charger
— USB: Programmable to 500mA for
USB Hi/Lo
— Adapter: Programmable to 1.5A Max
4.0V to 5.5V Input Voltage Range
Adapter Present Indicator (ADPP# Pin)
Adapter Presence Automatically Disables
USB Charging
High Level of Integration With Internal:
— Charging Devices
— Reverse Blocking Diodes
— Current Sensing
Automatic Recharge Sequencing
Digital Thermal Regulation in ADP Charge
Charge Reduction Loop in USB Charge
Battery Temperature Monitoring
Full Battery Charge Auto Turn-Off
Over-Voltage and Emergency Thermal
Protection
Power On Reset and Soft Start
Serial Interface Status Reporting
TDFN34-16 or TDFN44-16 Package
Applications
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Cellular Telephones
Digital Still Cameras
Hand-Held PCs
MP3 Players
Personal Data Assistants (PDAs)
Other Lithium-Ion/Polymer Battery-Powered
Devices
Typical Application
Enable
USB Input
USB Hi/Lo Select
USB
USBSEL
USBH
R
SETH
R
SETL
USBL
EN
CHR
BATT+
BAT
TS
CT
C
T
C2
10μF
AAT3686
BATT-
ADP Present
ADP Input
R
SET
ADPP#
ADP
ADPSET
STAT1
GND
DATA
STAT2
TEMP
Battery Pack
Serial Data
3686.2006.10.1.9
1