MIC79110

Simple 1.2A Linear Li-Ion Battery Charger

MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

October 2007

M9999-102507

General Description

The Micrel MIC79110 is a simple and accurate lithium ion

battery charger. The part features a built-in pass transistor,

precision programmable current limiting (±5%), and

precision voltage termination (±0.75% over temperature).

The MIC79110 packs full functionality into a small space.

Other features of the MIC79110 include two independent

indicators:

a

digital

End-of-Charge

signal

that

is

programmable with a resistor to ground, and an analog

current output that is proportional to the output current,

allowing for monitoring of the actual charging current.

Additional features include very low dropout (550mV over

the temperature range), thermal shutdown, and reverse

polarity protection. In the event the input voltage to the

charger is disconnected, the MIC79110 also provides

minimal reverse-current and reversed-battery protection.

Available in both fixed 4.2V and adjustable outputs, the

MIC79110 is offered in the leadless 10-pin 3mm x 3mm

MLF

–40˚C to +125˚C.

Data sheets and support documentation can be found on

Micrel’s web site at www.micrel.com.

Features

• Input voltage range: 2.5V to 16V

• High output voltage accuracy of ±0.75%

over –5°C to +60˚C

• Programmable end-of-charge flag

• Analog output proportional to output current

• Adjustable and fixed 4.2V output

• Low dropout voltage of 550mV at 700mA load, over

temperature

• 1.2A max charge current

• Excellent line and load regulation specifications

• Reverse current protection

• Thermal shutdown and current limit protection

• Junction temperature range: –40°C to +125°C

Applications

•

Cellular phones

•

PDAs

•

Digital cameras

•

Camcorders

•

MP3 players

•

Notebook PCs

•

Portable Meters

•

Cradle chargers

•

Car chargers

•

Battery packs

___________________________________________________________________________________________________________

Typical Application

SD

BAT

SNS

GND

MIC79110

4.2V

Li-Ion

Cell

SHUTDOWN

ENABLE

MIC79110 Typical Application