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.