from current conductor to die, greatly suppressing output
noise due to high dv/dt transients
•
Industry-leading noise performance with greatly
improved bandwidth through proprietary amplifier and
filter design techniques
•
High-bandwidth 120 kHz analog output for faster
response times in control applications
•
Filter pin allows user to filter the output for improved
resolution at lower bandwidth
•
Patented integrated digital temperature compensation
circuitry allows for near closed loop accuracy over
temperature in an open-loop sensor
•
Small footprint, low-profile SOIC8 package suitable for
space-constrained applications
•
Filter pin simplifies bandwidth limiting for better
resolution at lower frequencies
Continued on the next page…
DESCRIPTION
The Allegro
™
ACS725 current sensor IC is an economical and
precise solution for AC or DC current sensing in industrial,
automotive, commercial, and communications systems. The
small package is ideal for space-constrained applications
while also saving costs due to reduced board area. Typical
applications include motor control, load detection and
management, switched-mode power supplies, and overcurrent
fault protection.
The device consists of a precise, low-offset, linear Hall
sensor circuit with a copper conduction path located near the
surface of the die. Applied current flowing through this copper
conduction path generates a magnetic field which is sensed
by the integrated Hall IC and converted into a proportional
voltage. The current is sensed differentially in order to reject
common-mode fields, improving accuracy in magnetically
noisy environments. The inherent device accuracy is optimized
through the close proximity of the magnetic field to the Hall
transducer. A precise, proportional voltage is provided by the
low-offset, chopper-stabilized BiCMOS Hall IC, which is
programmed for accuracy after packaging. The output of the
device has a positive slope when an increasing current flows
through the primary copper conduction path (from pins 1 and
2, to pins 3 and 4), which is the path used for current sensing.
The internal resistance of this conductive path is 1.2 mΩ typical,
providing low power loss.
The terminals of the conductive path are electrically isolated
from the sensor leads (pins 5 through 8). This allows the
ACS725 current sensor IC to be used in high-side current sense
applications without the use of high-side differential amplifiers
or other costly isolation techniques.
Continued on the next page…
PACKAGE: 8-Pin SOIC (suffix LC)
pe d
Ty ste
te
TÜV America
Certificate Number:
U8V 14 11 54214 032
CB 14 11 54214 031
CB Certificate Number:
US-22334-A2-UL
Not to scale
1
+I
P
2
I
P
IP+
VCC
8
The ACS725 outputs an
analog signal, V
IOUT
, that
changes, proportionally,
with the bidirectional AC
or DC primary sensed
current, I
P
, within the
specified measurement
range. The FILTER pin
can be used to decrease
the bandwidth in order
to optimize the noise
performance.
ACS725
IP+
VIOUT
7
C
BYPASS
0.1 µF
C
F
1 nF
C
LOAD
3
–I
P
4
IP–
FILTER
6
IP–
GND
5
Typical Application
ACS725-DS, Rev. 10
MCO-0000160
July 3, 2018
ACS725
Automotive-Grade, Galvanically Isolated Current Sensor IC
With Common-Mode Field Rejection in a Small Footprint SOIC8 Package
•
3.3 V, single supply operation
•
Output voltage proportional to AC or DC current
•
Factory-trimmed sensitivity and quiescent output voltage for
improved accuracy
•
Chopper stabilization results in extremely stable quiescent
output voltage
•
Nearly zero magnetic hysteresis
•
Ratiometric output from supply voltage
FEATURES AND BENEFITS (continued)
The ACS725 is provided in a small, low-profile surface-mount
SOIC8 package. The leadframe is plated with 100% matte tin,
which is compatible with standard lead (Pb) free printed circuit
board assembly processes. Internally, the device is Pb-free, except
for flip-chip high-temperature Pb-based solder balls, currently
exempt from RoHS. The device is fully calibrated prior to shipment
from the factory.
DESCRIPTION (continued)
SELECTION GUIDE
Part Number
ACS725LLCTR-05AB-T
ACS725LLCTR-10AB-T
ACS725LLCTR-10AU-T
ACS725LLCTR-20AB-T
ACS725LLCTR-20AU-T
ACS725LLCTR-30AB-T
ACS725LLCTR-30AU-T
ACS725LLCTR-40AB-T
ACS725LLCTR-50AB-T
I
PR
(A)
±5
±10
10
±20
20
±30
30
±40
±50
Sens(Typ)
at V
CC
= 3.3 V
(mV/A)
264
132
264
66
132
44
88
33
26.4
–40 to 150
Tape and Reel, 3000 pieces per reel
T
A
(°C)
Packing*
*Contact Allegro for additional packing options.
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
2
ACS725
Automotive-Grade, Galvanically Isolated Current Sensor IC
With Common-Mode Field Rejection in a Small Footprint SOIC8 Package
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Characteristic
Supply Voltage
Reverse Supply Voltage
Output Voltage
Reverse Output Voltage
Operating Ambient Temperature
Junction Temperature
Storage Temperature
Symbol
V
CC
V
RCC
V
IOUT
V
RIOUT
T
A
T
J
(max)
T
stg
Range L
Notes
Rating
6
–0.1
V
CC
+ 0.5
–0.1
–40 to 150
165
–65 to 165
Units
V
V
V
V
°C
°C
°C
ISOLATION CHARACTERISTICS
Characteristic
Dielectric Surge Strength Test Voltage
Dielectric Strength Test Voltage
Working Voltage for Basic Isolation
Clearance
Creepage
Symbol
V
SURGE
V
ISO
V
WVBI
D
cl
D
cr
Notes
Tested ±5 pulses at 2/minute in compliance to IEC 61000-4-5
1.2 µs (rise) / 50 µs (width).
Agency type-tested for 60 seconds per UL standard 60950-
1 (edition 2). Production tested at V
ISO
for 1 second, in
accordance with UL 60950-1 (edition 2).
Maximum approved working voltage for basic (single)
isolation according UL 60950-1 (edition 2)
Minimum distance through air from IP leads to signal leads
Minimum distance along package body from IP leadds to
signal leads
Rating
6000
2400
420
297
4.2
4.2
Unit
V
V
RMS
V
pk
or VDC
V
rms
mm
mm
THERMAL CHARACTERISTICS
Characteristic
Package Thermal Resistance
(Junction to Ambient)
Package Thermal Resistance
(Junction to Lead)
Symbol
Test Conditions*
Mounted on the Allegro 85-0140 evaluation board with
800 mm
2
of 4 oz. copper on each side, connected to pins
1 and 2, and to pins 3 and 4, with thermal vias connecting
the layers. Performance values include the power
consumed by the PCB.
Mounted on the Allegro ASEK725 evaluation board.
Value
Units
R
θJA
23
°C/W
R
θJL
5
°C/W
*Additional thermal information available on the Allegro website.
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
3
ACS725
Automotive-Grade, Galvanically Isolated Current Sensor IC
With Common-Mode Field Rejection in a Small Footprint SOIC8 Package
V
CC
VCC
Master Current
Supply
To All Subcircuits
POR
Programming
Control
Hall
Current
Drive
IP+
IP+
Temperature
Sensor
EEPROM and
Control Logic
Offset
Control
C
BYPASS
0.1 µF
Sensitivity
Control
Dynamic Offset
Cancellation
IP–
IP–
GND
C
F
FILTER
Functional Block Diagram
Pinout Diagram and Terminal List Table
Terminal List Table
IP+
IP+
IP–
IP–
1
2
3
4
8
7
6
5
VCC
VIOUT
FILTER
GND
Number
1, 2
3, 4
5
6
7
8
Name
IP+
IP–
GND
FILTER
VIOUT
VCC
Description
Terminals for current being sensed; fused internally
Terminals for current being sensed; fused internally
Signal ground terminal
Terminal for external capacitor that sets bandwidth
Analog output signal
Device power supply terminal
Package LC, 8-Pin SOICN
Pinout Diagram
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
–
4
R
F(int)
+
–
+
VIOUT
ACS725
Automotive-Grade, Galvanically Isolated Current Sensor IC
With Common-Mode Field Rejection in a Small Footprint SOIC8 Package
COMMON ELECTRICAL CHARACTERISTICS
[1]
:
Valid through the full range of T
A
, V
CC
= 3.3 V, C
F
= 0, unless otherwise specified
Characteristic
Supply Voltage
Supply Current
Output Capacitance Load
Output Resistive Load
Primary Conductor Resistance
Internal Filter Resistance
[2]
Common Mode Field Rejection Ratio
Primary Hall Coupling Factor
Secondary Hall Coupling Factor
Hall plate Sensitivity Matching
Rise Time
Propagation Delay
Response Time
Bandwidth
Noise Density
Noise
Nonlinearity
Sensitivity Ratiometry Coefficient
Zero Current Output Ratiometry Coefficient
Saturation Voltage
[3]
Power-On Time
Shorted Output to Ground Current
Shorted Output to V
CC
Current
[1]
Device
Symbol
V
CC
I
CC
C
L
R
L
R
IP
R
F(int)
CMFRR
G1
G2
Sens
match
t
r
t
pd
t
RESPONSE
BW
I
ND
I
N
E
LIN
SENS_RAT_
COEF
QVO_RAT_
COEF
V
OH
V
OL
t
PO
I
sc(gnd)
I
sc(vcc)
Test Conditions
V
CC
= 3.3 V, output open
VIOUT to GND
VIOUT to GND
T
A
= 25°C
Uniform external magnetic field
T
A
= 25°C
T
A
= 25°C
T
A
= 25°C
I
P
= I
P
(max), T
A
= 25°C, C
L
= 1 nF
I
P
= I
P
(max), T
A
= 25°C, C
L
= 1 nF
I
P
= I
P
(max), T
A
= 25°C, C
L
= 1 nF
Small signal –3 dB; C
L
= 1 nF
Input referenced noise density;
T
A
= 25°C, C
L
= 1 nF
Input referenced noise: C
F
= 4.7 nF,
C
L
= 1 nF, BW = 18 kHz, T
A
= 25°C
Through full range of I
P
V
CC
= 3.0 to 3.6 V, T
A
= 25°C
V
CC
= 3.0 to 3.6 V, T
A
= 25°C
R
L
= 4.7 kΩ
R
L
= 4.7 kΩ
Output reaches 90% of steady-state
level, T
A
= 25°C, I
P
= I
PR
(max) applied
T
A
= 25°C
T
A
= 25°C
Min.
3
–
–
4.7
–
–
–
–
–
–
–
–
–
–
–
–
–1.5
–
–
–
–
–
–
–
Typ.
3.3
10
–
–
1.2
1.8
40
11
2.8
±1
3
2
4
120
200
27
–
1.3
1
V
CC
– 0.3
0.3
80
3.3
45
Max.
3.6
14
10
–
–
–
–
–
–
–
–
–
–
–
–
–
+1.5
–
–
–
–
–
–
–
Unit
V
mA
nF
kΩ
mΩ
kΩ
dB
G/A
G/A
%
μs
μs
μs
kHz
µA
(rms)
/
√Hz
mA
(rms)
%
–
–
V
V
μs
mA
mA
may be operated at higher primary current levels, I
P
, ambient temperatures, T
A
, and internal leadframe temperatures, provided the Maximum Junction Tempera-
ture, T
J
(max), is not exceeded.
[2]
R
F(int)
forms an RC circuit via the FILTER pin.
[3]
The sensor IC will continue to respond to current beyond the range of I until the high or low saturation voltage; however, the nonlinearity in this region will be worse than