High Sensitivity, 1 MHz, GMR-Based Current Sensor IC
in Space-Saving, Low Resistance QFN and SOIC-8 Packages
FEATURES AND BENEFITS
•
High sensitivity current sensor IC for sensing
up to 5 A (DC or AC)
•
1 MHz bandwidth with response time <550 ns
•
Low noise: 8 mA(rms) at 1 MHz
•
Non-ratiometric, analog output proportional to AC and
DC current
•
Single 3.3 V supply operation
•
High DC PSRR enables use with low accuracy
power supplies or batteries (3 to 4.5 V operation)
• 1.1 mΩ primary conductor resistance results in
low power loss
•
Small surface mount QFN-12 and SOIC-8 packages for
space-constrained applications
DESCRIPTION
The ACS70331 is Allegro’s first integrated, high sensitivity,
current sensor IC for <5 A current sensing applications. It
incorporates giant magneto-resistive (GMR) technology that
is 25 times more sensitive than traditional Hall-effect sensors
to sense the magnetic field generated by the current flowing
through the low resistance, integrated primary conductor.
The analog output provides a low noise high-speed signal,
which is proportional to the current flowing through the
primary. The response time of the part is typically 535 ns. The
ACS70331 is offered in four factory-programmed sensitivity
and offset levels to optimize performance over the desired
current measurement range.
The differential configuration of the GMR elements, relative to
the integrated current conductor, provides significant rejection
of stray magnetic fields, resulting in stable operation even in
magnetically noisy environments.
The ACS70331 operates from a single 3.3 V power supply
and is qualified over the full commercial temperature range
of –40°C to 85°C. It is offered in a low-profile, space-saving
surface mount QFN-12 and SOIC-8 packages.
PACKAGES
12-contact QFN
3 mm × 3 mm × 0.75 mm
(ES package)
Not to scale
8-contact SOIC
(OL package)
TYPICAL APPLICATION
C
BYPASS
0.1 µF
12
1
IP+
IP+
VCC
11
NC
VIOUT
10
C
LOAD
IP
NC
NC
8
3
IP -
2
IP+
VIOUT
7
1
IP+
VCC
8
C
BYPASS
0.1 µF
2
IP
ACS70331
NC
9
ACS70331
NC
3
4
IP–
IP–
6
7
GND
5
NC
6
4
IP -
GND
5
QFN-12
The output, VIOUT, of the ACS70331 responds
proportionally to the current flowing through IP.
SOIC-8
ACS70331-DS, Rev. 2
MCO-0000343
May 23, 2018
ACS70331
SELECTION GUIDE
Part Number
ACS70331EESATR-2P5U3
ACS70331EESATR-2P5B3
ACS70331EESATR-005U3
ACS70331EESATR-005B3
ACS70331EOLCTR-2P5U3
ACS70331EOLCTR-2P5B3
ACS70331EOLCTR-005U3
ACS70331EOLCTR-005B3
[1]
High Sensitivity, 1 MHz, GMR-Based Current Sensor IC
in Space-Saving, Low Resistance QFN and SOIC-8 Packages
Current Sensing
Range, I
PR
(A)
0 to 2.5
±2.5
0 to 5
±5
0 to 2.5
±2.5
0 to 5
±5
Sens (Typ)
(mV/A)
800
400
400
200
800
400
400
200
T
A
(°C)
Package
12-contact
QFN with fused
current loop
Packing
[1]
–40 to 85
1500 pieces per reel
–40 to 85
8-lead SOIC
3000 pieces per reel
Contact Allegro for additional packing options.
ABSOLUTE MAXIMUM RATINGS
Characteristic
Supply Voltage
Reverse Supply Voltage
Output Voltage
Reverse Output Voltage
Working Voltage
Maximum Continuous Current
[2]
Maximum Continuous External Field
[3]
Nominal Operating Ambient Temperature
Maximum Junction Temperature
[2]
Storage Temperature
[2]
Continuous
Symbol
V
CC
V
RCC
V
IOUT
V
RIOUT
V
WORKING
I
P(max)
B
T
A
T
J
(max)
T
stg
Range E
Notes
Rating
7
–0.1
6
–0.1
Units
V
V
V
V
V
A
G
°C
°C
°C
Voltage applied between pins 1 to 4 and pins 5 to 12 (QFN)
or pins 1 to 4 and pins 5 to 8 (SOIC)
100
±10
±50
–40 to 85
100
–65 to 125
currents above this may result in changes in performance. See lifetime drift section for sensor drift under different temperature and current conditions. Also,
see Thermal Performance and Overcurrent Capability section for allowable constant and transient currents.
[3]
Continuous magnetic fields above this may result in changes in performance.
[4]
The ACS70331 should be soldered using Allegro’s recommended soldering profile in (http://www.allegromicro.com/en/Design-Center/Technical-Documents/Semicon-