General Description

The MAX4069–MAX4072 low-cost, bidirectional, high-

side, current-sense amplifiers are ideal for monitoring

battery charge and discharge currents in notebooks,

cell phones, and other portable equipment. They fea-

ture up to 24V input common-mode voltage range, low

100µA supply current (which drops to only 10µA in

shutdown), and a total output error of less than 1.5%.

The wide 1.35V to 24V input common-mode range is

independent of the supply voltage, ensuring that the

current-sense feedback remains accurate even when

connected to a battery pack in deep discharge.

To achieve maximum flexibility, an external current-sense

resistor is used along with a Gain Select pin to choose

either 50V/V or 100V/V. A single output pin continuously

monitors the transition from charge to discharge and

avoids the need for a separate polarity output. The

MAX4070 contains an internal 2.5V reference. The

charging current is represented by an output voltage

2.5V to GND. The MAX4071 is similar, but with a refer-

ence voltage of 1.5V. The MAX4069 has an adjustable

reference voltage, set by two external resistors. The

MAX4072 has an input for an external reference.

The MAX4069/MAX4071/MAX4072 operate from a 2.7V to

24V single supply. The MAX4070 operates from a 3.6V to

24V single supply. All devices are specified over the

automotive operating temperature range, -40

°C to

+125

°C. The MAX4070/MAX4071/MAX4072 are available

in 8-pin µMAX and 8-pin thin QFN packages. The

Applications

Notebook Fuel Gauging

Smart-Battery Packs/Chargers

Motor Control

Power-Management Systems

Cell-Phone Battery-Current Monitoring

Features

♦ Bidirectional, Compact, Current-Sense Solution

♦ Total Output Error Less than 1.5%

♦ Selectable Gain of 50V/V or 100V/V

♦ Wide 1.35V to 24V Common-Mode Range

Independent of Supply Voltage

♦ 2.7V to 24V Single-Supply Operation

♦ Internal Precision Reference

Adjustable (MAX4069)

2.50V (MAX4070)

1.50V (MAX4071)

♦ Low 100µA Supply Current

♦ 10µA Supply Current in Shutdown

♦ Available in Space-Saving Packages

8-Pin Thin QFN (MAX4070/MAX4071/MAX4072)

8-Pin µMAX (MAX4070/MAX4071MAX4072)

10-Pin µMAX (MAX4069)

Bidirectional, High-Side, Current-Sense

Amplifiers with Reference

________________________________________________________________

Maxim Integrated Products

1

Ordering Information

MAX4070

FROM BATTERY

CHARGER

LOAD

TO ADC

2.5V

GSEL

GND

RS-

RS+

REFOUT

OUT

SHDN

Typical Operating Circuit

19-2423; Rev 3; 11/08

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART

TEMP RANGE

PIN-PACKAGE

TOP

MARK

MAX4069AUB

-40

°C to +125°C 10 µMAX

—

MAX4070AUA

-40

°C to +125°C 8 µMAX

—

MAX4070ATA

-40

°C to +125°C 8 Thin QFN-EP*

ABN

MAX4071AUA

-40

°C to +125°C 8 µMAX

—

MAX4071ATA

-40

°C to +125°C 8 Thin QFN-EP*

ABO

MAX4072AUA

-40

°C to +125°C 8 µMAX

—

MAX4072ATA

-40

°C to +125°C 8 Thin QFN-EP*

ABP

Pin Configurations and Selector Guide appear at end of

data sheet.

*

EP = Exposed pad.

µMAX is a registered trademark of Maxim Integrated Products, Inc.