General Description
The MAX4080/MAX4081 are high-side, current-sense
amplifiers with an input voltage range that extends from
4.5V to 76V making them ideal for telecom, automotive,
backplane, and other systems where high-voltage cur-
rent monitoring is critical. The MAX4080 is designed for
unidirectional current-sense applications and the
MAX4081 allows bidirectional current sensing. The
MAX4081 single output pin continuously monitors the
transition from charge to discharge and avoids the
need for a separate polarity output. The MAX4081
requires an external reference to set the zero-current
output level (V
SENSE
= 0V). The charging current is rep-
resented by an output voltage from V
REF
to V
CC
, while
discharge current is given from V
REF
to GND.
For maximum versatility, the 76V input voltage range
applies independently to both supply voltage (V
CC
)
and common-mode input voltage (V
RS+
). High-side
current monitoring does not interfere with the ground
path of the load being measured, making the
MAX4080/MAX4081 particularly useful in a wide range
of high-voltage systems.
The combination of three gain versions (5V/V, 20V/V,
60V/V = F, T, S suffix) and a user-selectable, external
sense resistor sets the full-scale current reading and its
proportional output voltage. The MAX4080/MAX4081
offer a high level of integration, resulting in a simple,
accurate, and compact current-sense solution.
The MAX4080/MAX4081 operate from a 4.5V to 76V sin-
gle supply and draw only 75μA of supply current. These
devices are specified over the automotive operating
temperature range (-40°C to +125°C) and are available
in a space-saving 8-pin μMAX or SO package.
Applications
Automotive (12V, 24V, or 42V Batteries)
48V Telecom and Backplane Current
Measurement
Bidirectional Motor Control
Power-Management Systems
Avalanche Photodiode and PIN-Diode Current
Monitoring
General System/Board-Level Current Sensing
Precision High-Voltage Current Sources
Features
o
Wide 4.5V to 76V Input Common-Mode Range
o
Bidirectional or Unidirectional I
SENSE
o
Low-Cost, Compact, Current-Sense Solution
o
Three Gain Versions Available
5V/V (MAX4080F/MAX4081F)
20V/V (MAX4080T/MAX4081T)
60V/V (MAX4080S/MAX4081S)
o
±0.1% Full-Scale Accuracy
o
Low 100μV Input Offset Voltage
o
Independent Operating Supply Voltage
o
75μA Supply Current (MAX4080)
o
Reference Input for Bidirectional OUT (MAX4081)
o
Available in a Space-Saving 8-Pin μMAX Package
Ordering Information
M
76V, High-Side, Current-Sense Amplifiers with
Voltage Output
________________________________________________________________
Maxim Integrated Products
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.
1
N.C.
OUT
GND
1
2
8
7
RS-
N.C.
V
CC
N.C.
RS+
μ
MAX/SO
TOP VIEW
3
4
6
5
MAX4080
REF1B
OUT
GND
1
2
8
7
RS-
REF1A
V
CC
N.C.
RS+
μ
MAX/SO
3
4
6
5
MAX4081
Pin Configurations
19-2562; Rev 0; 10/02
PART
TEMP RANGE
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
-40
°
C to +125
°
C
PIN-PACKAGE
8 μMAX
8 SO
8 μMAX
8 SO
8 μMAX
8 SO
8 μMAX
8 SO
8 μMAX
8 SO
8 μMAX
8 SO
MAX4080
FAUA
MAX4080FASA
MAX4080TAUA
MAX4080TASA
MAX4080SAUA
MAX4080SASA
MAX4081
FAUA
MAX4081FASA
MAX4081TAUA
MAX4081TASA
MAX4081SAUA
MAX4081SASA
Selector Guide appears at end of data sheet.