MAX4069–MAX4072
Bidirectional, High-Side, Current-Sense
Amplifiers with Reference
General Description
Features
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 feature 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.
● 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)
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 from 2.5V to
●
●
Lowꢀ100μAꢀSupplyꢀCurrent
10μAꢀSupplyꢀCurrentꢀinꢀShutdown
● Available in Space-Saving Packages
•ꢀ 8-Pin Thin QFN (MAX4070/MAX4071/MAX4072)
•ꢀ 8-PinꢀμMAXꢀ(MAX4070/MAX4071/MAX4072)
•ꢀ 10-PinꢀμMAXꢀ(MAX4069)
V
CC
, while discharge current is given from 2.5V to GND.
The MAX4071 is similar, but with a reference 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.
Ordering Information
TOP
MARK
PART
TEMP RANGE PIN-PACKAGE
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*
MAX4071AUA+ -40°C to +125°C 8 µMAX
MAX4071ATA+ -40°C to +125°C 8 Thin QFN-EP*
MAX4072AUA+ -40°C to +125°C 8 µMAX
MAX4072ATA+ -40°C to +125°C 8 Thin QFN-EP*
*EP = Exposed pad.
—
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 MAX4069
—
ADH
—
ADI
—
®
is available in a 10-pin µMAX package.
ADJ
Applications
● Notebook Fuel Gauging
● Smart-Battery Packs/Chargers
● Motor Control
● Power-Management Systems
● Cell-Phone Battery-Current Monitoring
Typical Operating Circuit
FROM BATTERY
CHARGER
R
SENSE
V
BATT
= 1.35V TO 24V
LOAD
RS-
RS+
V
CC
= 3.6V TO 24V
V
CC
MAX4070
μMAX is a registered trademark of Maxim Integrated Products,
Inc.
GSEL
SHDN
OUT
TO ADC
REFOUT
2.5V
Pin Configurations and Selector Guide appear at end of
data sheet.
GND
19-2423; Rev 4; 11/16