Data Brief

For further information contact your local STMicroelectronics sales office.

January 2007

Rev 1

1/3

3

STw4102

Dual source USB Li-Ion charger with gas gauge

Features

■

Constant current constant voltage (CCCV)

charger

■

Dual charging source (main adaptor or USB

cable)

■

Fast charge current control up to 1A for main

adaptor and up to 500mA for USB

■

Internal power device and sense resistor,

option for external components for current

higher than 1A

■

Programmable charge voltage (4.1V, 4.2V,

4.3V, 4.35V) with 1% accuracy

■

Thermal regulation

■

Trickle charge mode at low battery voltage

■

Main adaptor voltage up to 16V

■

Battery overvoltage protection at 4.7V

■

Gas gauge with 13 bit AD converter

■

Battery voltage monitor with 7-12 bit ADC

■

I2C interface for device monitoring and control

■

Charge status output pin

■

Power detection output pin

■

Programmable watchdog security timer

■

4.7V LDO regulator (external pmos)

Applications

■

Cellular phones (GSM, CDMA, WCDMA),

PDA, MP3 players, cordless phones

■

Digital camera, USB appliances, bluetooth

Description

The STw4102 is a stand-alone constant-current

constant-voltage (CCCV) linear charger

dedicated for Li-Ion battery.

The STw4102 allows dual charging capability

using the main input adaptor up to 1A (Wall

adaptor, Car adaptor) or USB cable up to 500mA

without external component. Upper 1A charging is

possible by adding just one external transistor.

The STw4102 offers programmable fast charge

current up to 1A with external resistor. A thermal

regulation circuitry limits the charge current

against the die high power dissipation or high

ambient temperature. An end of charge output pin

indicates the charge termination when the fast

charge current drops below 10% of the

programmed current value.

The STw4102 contains an accurate gas gauge

based on a 13 bit AD converter. External resistor

is used between battery and ground to sense a

charge/discharge curent. With a typical 30

mOhms resistor, current can be up to 2.5A.

QFN 24

Plastic Micropackage

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