FEATURES
2• Integrated Power FETs with Thermal
Regulation
• Charges from Either an AC Wall Adapter or
USB Power Source with Automatic Source
Selection
• 50 mA to 1000 mA Charge Currents Using AC
Wall Adapter
• Pin-Selectable USB Charge Currents of 100
mA or 500 mA
• LDO Mode with 1A of Source Current is
Automatically Invoked When the Battery is
Absent and the AC Wall Adapter is Connected
• Continuous Battery Temperature Monitoring
• Built-in Multiple Safety Timers
• Charge Status Indication
• Continuous Over-current and Temperature
Protection
• Near-depleted Battery Pre-conditioning
• Sleep Mode with Ultra Low Quiescent Current
• On-board Kelvin-sensing Achieves ±0.35%
Termination Accuracy
• Maintenance Mode with Automatic Recharge
• Thermally Enhanced 3 mm x 3 mm WSON
Package

APPLICATIONS
• Smartphones
• Digital Still Cameras
• PDAs
• Hard Drive and Flash-based MP3 Players
• USB-powered Devices

DESCRIPTION
The LM3658 is a single chip charger IC designed for
handheld applications. It can safely charge and
maintain a single cell Li-Ion/Polymer battery operating
from an AC wall adapter or USB power source. Input
power source selection of USB/AC is automatic. With
both power sources present, the AC power source
has priority. Charge current is programmed through
an external resistor when operating from an AC wall
adapter allowing charge currents from 50 mA to 1000
mA. When the battery is charged using USB power,
charge currents of 100 mA or 500 mA are pin-
selectable. The termination voltage is controlled to
within ±0.35% of 4.2V.
The LM3658 requires few external components and
integrates internal power FETs, reverse current
protection and current sensing. The internal power
FETs are thermally regulated to obtain the most efficient charging rate for a given ambient
temperature.
The LM3658 operates in five modes: pre-qualification
mode, constant-current mode, constant-voltage
mode, top-off mode and maintenance mode.
Additionally, the charger IC operates as a linear
regulator in “LDO mode”, when the AC wall adapter is
connected and no battery is present. Optimal battery
management is obtained through thermal regulation,
battery temperature measurement and multiple safety
timers. The LM3658 provides two open-drain outputs
for LED status indication or connection to GPIOs.