ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
DESCRIPTION
FEATURES AND BENEFITS
• Differential Hall sensing rejects common-mode fields
• Patented integrated digital temperature compensation
circuitry allows for near closed loop accuracy over
temperature in an open loop sensor
• UL60950-1 (ed. 2) certified
□ Dielectric Strength Voltage = 4.8 kVRMS
□ Basic Isolation Working Voltage = 1097 VRMS
□ Reinforced Isolation Working Voltage = 565 VRMS
• Industry-leading noise performance with greatly
improved bandwidth through proprietary amplifier and
filter design techniques
• Filter pin allows user to filter output for improved
resolution at lower bandwidth
• 0.85 mΩ primary conductor resistance for low power
loss and high inrush current withstand capability
• Low-profile SOIC16 package suitable for spaceconstrained applications
• 4.5 to 5.5 V single supply operation
• Output voltage proportional to AC or DC current
The Allegro™ ACS724KMA current sensor IC is an economical
and precise solution for AC or DC current sensing in industrial,
commercial, and communication 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, chopperstabilized BiCMOS Hall IC, which includes Allegro’s patented
digital temperature compensation, resulting in extremely accurate
performance over temperature. The output of the device has
a positive slope when an increasing current flows through the
primary copper conduction path (from pins 1 through 4, to
pins 5 through 8), which is the path used for current sensing.
The internal resistance of this conductive path is 0.85 mΩ
typical, providing low power loss.
Continued on the next page…
TÜV America
Certificate Number:
U8V 16 03 54214 040
CB 16 03 54214 039
CB Certificate Number:
US-32210-M1-UL
The terminals of the conductive path are electrically isolated
from the sensor leads (pins 9 through 16). This allows the
ACS724KMA 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.
PACKAGE: 16-pin SOICW (suffix MA)
Continued on the next page…
Not to scale
+IP
1
IP+
2
IP+
3
IP+
4
IP+
NC
GND
NC
FILTER
IP
–IP
ACS724KMA
5
IP–
6
IP–
7
IP–
8
IP–
VIOUT
NC
VCC
NC
16
The ACS724KMA outputs
an analog signal, VIOUT , that
changes proportionally with
the bidirectional AC or DC
primary sensed current, IP ,
within the specified measurement range.
15
14
13
12
11
CL
10
9
CBYPASS
0.1 µF
CF
1 nF
The FILTER pin can be used
to decrease the bandwidth in
order to optimize the noise
performance.
Typical Application
ACS724KMA-DS, Rev. 18
MCO-0000217
February 5, 2021
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
FEATURES AND BENEFITS (continued)
• 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
DESCRIPTION (continued)
The ACS724KMA is provided in a low-profile surface-mount
SOIC16 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. The device is
fully calibrated prior to shipment from the factory.
SELECTION GUIDE
Part Number
IPR (A)
Sens(Typ) at VCC = 5 V
(mV/A)
ACS724KMATR-12AB-T
±12
166
ACS724KMATR-20AB-T
±20
100
ACS724KMATR-30AB-T
±30
66
ACS724KMATR-30AU-T
30
132
ACS724KMATR-50AB-T
±50
40
ACS724KMATR-65AB-T
±65
30.75
[1] Contact Allegro
TA (°C)
Packing [1]
–40 to 125
Tape and Reel, 1000 pieces per reel
for additional packing options.
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
2
ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ABSOLUTE MAXIMUM RATINGS
Characteristic
Symbol
Notes
Rating
Units
Supply Voltage
VCC
6
V
Reverse Supply Voltage
VRCC
–0.1
V
Output Voltage
VIOUT
VCC + 0.5
V
Reverse Output Voltage
VRIOUT
–0.1
V
Maximum Continuous Current
ICMAX
TA = 25°C
60
A
TA
Range K
–40 to 125
°C
Operating Ambient Temperature
Junction Temperature
TJ(max)
165
°C
Storage Temperature
Tstg
–65 to 165
°C
ESD RATINGS
Characteristic
Symbol
Test Conditions
Value
Unit
Human Body Model
VHBM
Per AEC-Q100
±2
kV
Charged Device Model
VCDM
Per AEC-Q100
±1
kV
ISOLATION CHARACTERISTICS
Characteristic
Symbol
Notes
Rating
Unit
10000
V
Dielectric Surge Strength Test Voltage
VSURGE
Tested ±5 pulses at 2/minute in compliance to IEC 61000-4-5
1.2 µs (rise) / 50 µs (width).
Surge Strength Test Current
ISURGE
Tested ±5 pulses at 3/minute with 8 µs (rise) / 20 µs (width)
13000
A
VISO
Agency type-tested for 60 seconds per UL 60950-1
(edition 2). Production tested at 3000 VRMS for 1 second, in
accordance with UL 60950-1 (edition 2).
4800
VRMS
1550
VPK or VDC
1097
VRMS
800
VPK or VDC
565
VRMS
Dielectric Strength Test Voltage
Working Voltage for Basic Isolation
VWVBI
Maximum approved working voltage for basic (single) isolation
according to UL 60950-1 (edition 2).
Working Voltage for Reinforced Isolation
VWVRI
Maximum approved working voltage for reinforced isolation
according to UL 60950-1 (edition 2).
Clearance
Dcl
Minimum distance through air from IP leads to signal leads.
8.2
mm
Creepage
Dcr
Minimum distance along package body from IP leads to signal
leads
8.2
mm
Distance Through Insulation
DTI
Minimum internal distance through insulation
90
µm
Comparative Tracking Index
CTI
Material Group II
400 to 599
V
THERMAL CHARACTERISTICS [1]
Characteristic
Symbol
Test Conditions
Value
Unit
23
°C/W
5
°C/W
Junction-to-Ambient Thermal Resistance
RθJA
Mounted on the Allegro ASEK724/5 MA evaluation board. Performance
values include the power consumed by the PCB. [2]
Junction-to-Lead Thermal Resistance
RθJL
Mounted on the Allegro ASEK724/5 MA evaluation board. [2]
[1]
[2]
Refer to the die temperature curves versus DC current plot (page 16). Additional thermal information is available on the Allegro website.
The Allegro evaluation board has 1500 mm2 of 4 oz. copper on each side, connected to pins 1 through 4 and pins 5 through 8, with thermal vias connecting the layers. Performance values include the power consumed by the PCB. Further information about board design and thermal performance
also can be found in the Applications Information section of this datasheet.
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
3
ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
VCC
VCC
Master Current
Supply
To All Subcircuits
Programming
Control
POR
Hall
Current
Drive
Temperature
Sensor
IP+
IP+
IP+
IP+
CBYPASS
0.1 µF
EEPROM and
Control Logic
Offset
Control
Dynamic Offset
Cancellation
Sensitivity
Control
IP–
IP–
IP–
IP–
+
–
RF(int)
GND
CF
–
VIOUT
+
FILTER
Functional Block Diagram
IP+ 1
16 NC
Terminal List Table
IP+ 2
15 GND
Number
Name
IP+ 3
14 NC
1, 2, 3, 4
IP+
Terminals for current being sensed; fused internally
IP+ 4
13 FILTER
5, 6, 7, 8
IP-
Terminals for current being sensed; fused internally
IP-
12 VIOUT
9, 16
NC
No internal connection; recommended to be left unconnected in order to
maintain high creepage
10
VCC
11, 14
NC
12
VIOUT
Analog output signal
13
FILTER
Terminal for external capacitor that sets bandwidth
15
GND
5
IP-
6
11 NC
IP-
7
10 VCC
IP-
8
9 NC
Pinout Diagram
Description
Device power supply terminal
No internal connection; recommened to connect to GND for the best ESD
performance
Signal ground terminal
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
4
ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
COMMON ELECTRICAL CHARACTERISTICS [1]: Valid through the full range of TA = –40°C to 125°C and VCC = 5 V,
unless otherwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
4.5
5
5.5
V
–
10
14
mA
Supply Voltage
VCC
Supply Current
ICC
VCC within VCC(min) and VCC(max)
Output Capacitance Load
CL
VIOUT to GND
–
–
10
nF
Output Resistive Load
RL
VIOUT to GND
4.7
–
–
kΩ
Primary Conductor Resistance
RIP
TA = 25°C
–
0.85
–
mΩ
Primary Conductor Inductance
LIP
TA = 25°C
–
4
–
nH
Internal Filter
Resistance [2]
Common Mode Field Rejection Ratio
RF(INT)
CMFRR
–
1.7
–
kΩ
Uniform external magnetic field
–
40
–
dB
Primary Hall Coupling Factor
G1
TA = 25°C
–
4.5
–
G/A
Secondary Hall Coupling Factor
G2
TA = 25°C
–
0.5
–
G/A
SensMATCH
TA = 25°C
–
±1
–
%
Hall Plate Sensitivity Matching
Hysteresis
IHYS
Difference in offset after a ±40 A pulse
–
150
–
mA
Rise Time
tr
TA = 25°C, CL = 1 nF
–
3
–
μs
tpd
TA = 25°C, CL = 1 nF
–
2
–
μs
tRESPONSE
TA = 25°C, CL = 1 nF
–
4
–
μs
Propagation Delay
Response Time
Output Slew Rate
SR
TA = 25°C, CL = 1 nF
–
0.53
–
V/μs
Internal Bandwidth
BW
Small signal –3 dB, CL = 1 nF
–
120
–
kHz
Noise Density
IND
Input-referenced noise density;
TA = 25°C, CL = 1 nF
–
450
–
µARMS/
√Hz
Noise
IN
Input-referenced noise; CF = 4.7 nF,
CL = 1 nF, BW = 18 kHz, TA = 25°C
–
60
–
mARMS
Through full range of IP
–
±1
Nonlinearity
ELIN
%
Sensitivity Ratiometry Coefficient
SENS_RAT_
COEF
VCC = 4.5 to 5.5 V, TA = 25°C
–
1.3
–
–
Zero-Current Output Ratiometry Coefficient
QVO_RAT_
COEF
VCC = 4.5 to 5.5 V, TA = 25°C
–
1
–
–
Saturation Voltage [3]
Power-On Time
VOH
RL = 4.7 kΩ, TA = 25°C
VCC – 0.5
–
–
V
VOL
RL = 4.7 kΩ, TA = 25°C
–
–
0.5
V
tPO
Output reaches 90% of steady-state
level, TA = 25°C, IP = IPR(max) applied
–
80
–
μs
Shorted Output to Ground Current
ISC(GND)
TA = 25°C
–
3.3
–
mA
Shorted Output to VCC Current
ISC(VCC)
TA = 25°C
–
45
–
mA
Device may be operated at higher primary current levels, IP , ambient temperatures, TA , and internal leadframe temperatures, provided the Maximum Junction Temperature, TJ(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
P
through the rest of the measurement range.
[1]
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
5
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-12AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ. [1]
Max.
Units
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
Zero Current Output Voltage
–12
–
12
A
Sens
IPR
IPR(min) < IP < IPR(max)
–
166
–
mV/A
VIOUT(Q)
Bidirectional; IP = 0 A
–
VCC ×
0.5
–
V
IP = IPR(max), TA = 25°C to 125°C
–2.5
±1
2.5
%
IP = IPR(max), TA = –40°C to 25°C
–
±3
–
%
–2
±1
2
%
ACCURACY PERFORMANCE
Total Output Error [2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
TA = 25°C to 125°C, measured at IP = IPR(max)
TA = –40°C to 25°C, measured at IP = IPR(max)
–
±2.8
–
%
IP = 0 A, TA = 25°C to 125°C
–15
±5
15
mV
IP = 0 A, TA = –40°C to 25°C
–
±20
–
mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
[3] A single part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[1]
[2]
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
6
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-20AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.[1]
Max.
Units
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
Zero Current Output Voltage
–20
–
20
A
Sens
IPR
IPR(min) < IP < IPR(max)
–
100
–
mV/A
VIOUT(Q)
Bidirectional; IP = 0 A
–
VCC ×
0.5
–
V
IP = IPR(max), TA = 25°C to 125°C
–2.5
±1
2.5
%
IP = IPR(max), TA = –40°C to 25°C
–
±3
–
%
–2
±1
2
%
ACCURACY PERFORMANCE
Total Output Error [2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
TA = 25°C to 125°C, measured at IP = IPR(max)
TA = –40°C to 25°C, measured at IP = IPR(max)
–
±2.8
–
%
IP = 0 A, TA = 25°C to 125°C
–15
±5
15
mV
IP = 0 A, TA = –40°C to 25°C
–
±20
–
mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
[3] A single part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[1]
[2]
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
7
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-30AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.[1]
Max.
Units
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
Zero Current Output Voltage
–30
–
30
A
Sens
IPR
IPR(min) < IP < IPR(max)
–
66
–
mV/A
VIOUT(Q)
Bidirectional; IP = 0 A
–
VCC ×
0.5
–
V
IP = IPR(max), TA = 25°C to 125°C
–2.5
±0.8
2.5
%
IP = IPR(max), TA = –40°C to 25°C
–
±2.7
–
%
–2
±0.7
2
%
ACCURACY PERFORMANCE
Total Output Error [2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
TA = 25°C to 125°C, measured at IP = IPR(max)
TA = –40°C to 25°C, measured at IP = IPR(max)
–
±2.6
–
%
IP = 0 A, TA = 25°C to 125°C
–15
±7
15
mV
IP = 0 A, TA = –40°C to 25°C
–
±15
–
mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
[1]
[2]
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[3] A single
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
8
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-30AU PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.[1]
Max.
Units
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
Zero Current Output Voltage
IPR
Sens
VIOUT(Q)
0
–
30
A
IPR(min) < IP < IPR(max)
–
132
–
mV/A
Unidirectional; IP = 0 A
–
VCC ×
0.1
–
V
IP = IPR(max), TA = 25°C to 125°C
–2.5
±0.7
2.5
%
IP = IPR(max), TA = –40°C to 25°C
–
±2.5
–
%
–2
±0.7
2
%
ACCURACY PERFORMANCE
Total Output Error [2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
TA = 25°C to 125°C, measured at IP = IPR(max)
TA = –40°C to 25°C, measured at IP = IPR(max)
–
±2.5
–
%
IP = 0 A, TA = 25°C to 125°C
–15
±7
15
mV
IP = 0 A, TA = –40°C to 25°C
–
±20
–
mV
Lifetime Drift Characteristics
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
[3] A single part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[1]
[2]
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
9
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-50AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.[1]
Max.
Units
–50
–
50
A
–
40
–
mV/A
–
VCC ×
0.5
–
V
IP = IPR(max), TA = 25°C
–1.2
–
1.2
%
IP = IPR(max), TA = 125°C
–1.2
–
1.2
%
IP = IPR(max), TA = 0°C
–1.2
–
1.2
%
TA = 25°C, measured at IP = IPR(max)
–1
–
1
%
TA = 125°C, measured at IP = IPR(max)
–1
–
1
%
TA = 0°C, measured at IP = IPR(max)
–1
–
1
%
IP = 0 A; TA = 25°C
–5
–
5
mV
IP = 0 A; TA = 125°C
–7
–
7
mV
IP = 0 A; TA = 0°C
–7
–
7
mV
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
IPR
Sens
Zero Current Output Voltage
VIOUT(Q)
IPR(min) < IP < IPR(max)
Bidirectional; IP = 0 A
ACCURACY PERFORMANCE
Total Output Error
[2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
[3] A single part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[1]
[2]
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
10
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS724KMA
xKMATR-65AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 5 V, unless oth-
erwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.[1]
Max.
Units
NOMINAL PERFORMANCE
Current Sensing Range
Sensitivity
Zero Current Output Voltage
–65
–
65
A
Sens
IPR
IPR(min) < IP < IPR(max)
–
30.75
–
mV/A
VIOUT(Q)
Bidirectional; IP = 0 A
–
VCC ×
0.5
–
V
IP = IPR(max), TA = 25°C to 125°C
–2.5
±1
2.5
%
IP = IPR(max), TA = –40°C to 25°C
–
±3
–
%
–2
±1
2
%
ACCURACY PERFORMANCE
Total Output Error [2]
ETOT
TOTAL OUTPUT ERROR COMPONENTS
Sensitivity Error
Voltage Offset Error
ESENS
VOE
[3]:
ETOT = ESENS + 100 × VOE/(Sens × IP)
TA = 25°C to 125°C, measured at IP = IPR(max)
TA = –40°C to 25°C, measured at IP = IPR(max)
–
±2.8
–
%
IP = 0 A, TA = 25°C to 125°C
–15
±5
15
mV
IP = 0 A, TA = –40°C to 25°C
–
±20
–
mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift
Esens_drift
–
±1
–
%
Total Output Error Lifetime Drift
Etot_drift
–
±1
–
%
[1]
[2]
Typical values with +/- are 3 sigma values.
Percentage of IP , with IP = IPR(max).
part will not have both the maximum/minimum sensitivity error and maximum/minimum offset voltage, as that would violate the maximum/minimum total output
error specification. Also, 3 sigma distribution values are combined by taking the square root of the sum of the squares. See Application Information section.
[3] A single
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ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
CHARACTERISTIC PERFORMANCE
ACS724 TYPICAL FREQUENCY RESPONSE
For information regarding bandwidth characterization methods used for the ACS724, see the “Characterizing System Bandwidth”
application note (https://allegromicro.com/en/insights-and-innovations/technical-documents/hall-effect-sensor-ic-publications/an%20
effective%20method%20for%20characterizing%20system%20bandwidth-an296169) on the Allegro website.
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ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
RESPONSE CHARACTERISTICS DEFINITIONS AND PERFORMANCE DATA
Response Time (tRESPONSE)
Rise Time (tr)
The time interval between a) when the sensed input current
reaches 90% of its final value, and b) when the sensor output
reaches 90% of its full-scale value.
The time interval between a) when the sensor reaches 10% of
its full-scale value, and b) when it reaches 90% of its full-scale
value.
The time interval between a) when the sensed input current
reaches 20% of its full-scale value, and b) when the sensor output
reaches 20% of its full-scale value.
The rate of change (V/µs) in the output voltage from a) when the
sensor reaches 10% of its full-scale value, and b) when it reaches
90% of its full-scale value.
Propagation Delay (tpd)
Output Slew Rate (SR)
Response Time, Propagation Delay, Rise Time, and Output Slew Rate
Applied current step with 10%-90% rise time = 1 μs
Test Conditions: TA = 25°C, CBYPASS = 0.1 µF, CL = 0 F
t RESPONSE
SR [V/μs]
t pd
tr
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ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
POWER ON FUNCTIONAL DESCRIPTION AND PERFORMANCE DATA
Power-On Time (tPO)
Power-On Profile
When the supply is ramped to its operating voltage, the device
requires a finite amount of time to power its internal components
before responding to an input magnetic field. Power-On Delay
Time (tPO) is defined as the time interval between a) the power
supply has reached its minimum specified operating voltage
(VCC(min)), and b) when the sensor output has settled within
±10% of its steady-state value under an applied magnetic field.
After applying power, the part remains off in a known state
referred to as Power-on Reset, or POR. The device stays in this
state until the voltage reaches a point at which the device will
remain powered. The power-on profile below illustrates the
intended power on/off. A pull-down resistor was used on the
output of the tested device.
Power-On Time (tPO)
Test Conditions: TA = 25°C, CBYPASS = 0.1 µF, RPD = 10 kΩ
Power-On Profile
Supply voltage ramp rate = 1V/ms
Test Conditions: TA = 25°C, CBYPASS = 0.1 µF, RPD = 10 kΩ
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High-Accuracy, Hall-Effect-Based Current Sensor IC
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ACS724KMA
DEFINITIONS OF ACCURACY CHARACTERISTICS
Sensitivity (Sens)
The change in sensor IC output in response to a 1 A change
through the primary conductor. The sensitivity is the product
of the magnetic coupling factor (G/A) (1 G = 0.1 mT) and the
linear IC amplifier gain (mV/G). The linear IC amplifier gain is
programmed at the factory to optimize the sensitivity (mV/A) for
the full-scale current of the device.
sensitivity error, and at relatively low currents, ETOT will be mostly
due to Offset Voltage (VOE ). In fact, at IP = 0, ETOT approaches
infinity due to the offset. This is illustrated in Figure 1 and Figure 2.
Figure 1 shows a distribution of output voltages versus IP at 25°C
and across temperature. Figure 2 shows the corresponding ETOT
versus IP .
Increasing
VIOUT (V)
Nonlinearity (ELIN)
The nonlinearity is a measure of how linear the output of the sensor IC is over the full current measurement range. The nonlinearity is calculated as:
{ [
ELIN = 1–
VIOUT (IPR(max)) – VIOUT(Q)
2 × VIOUT (IPR(max)/2) – VIOUT(Q)
[{
Accuracy at
25°C Only
IPR(min)
–IP (A)
Full Scale IP
Accuracy at
25°C Only
Decreasing
VIOUT (V)
Accuracy Across
Temperature
Figure 1: Output Voltage versus Sensed Current
+ETOT
The deviation of the device output from its ideal quiescent value
of 0.5 × VCC (bidirectional) or 0.1 × VCC (unidirectional) due to
nonmagnetic causes. To convert this voltage to amperes, divide
by the device sensitivity, Sens.
Across Temperature
25°C Only
Total Output Error (ETOT)
The difference between the current measurement from the sensor
IC and the actual current (IP), relative to the actual current. This
is equivalent to the difference between the ideal output voltage
and the actual output voltage, divided by the ideal sensitivity,
relative to the current flowing through the primary conduction
path:
VIOUT_ideal(IP) – VIOUT(IP)
Sensideal(IP) × IP
IPR(max)
0A
Offset Voltage (VOE)
ETOT(IP) =
+IP (A)
VIOUT(Q)
Zero Current Output Voltage (VIOUT(Q))
The output of the sensor when the primary current is zero. For
a unipolar supply voltage, it nominally remains at 0.5 × VCC for
a bidirectional device and 0.1 × VCC for a unidirectional device.
For example, in the case of a bidirectional output device, VCC =
5.0 V translates into VIOUT(Q) = 2.50 V. Variation in VIOUT(Q) can
be attributed to the resolution of the Allegro linear IC quiescent
voltage trim and thermal drift.
Accuracy at
25°C Only
Ideal VIOUT
Accuracy Across
Temperature
× 100 (%)
where VIOUT(IPR(max)) is the output of the sensor IC with the
maximum measurement current flowing through it and
VIOUT(IPR(max)/2) is the output of the sensor IC with half of the
maximum measurement current flowing through it.
Accuracy Across
Temperature
× 100 (%)
The Total Output Error incorporates all sources of error and is a
function of IP . At relatively high currents, ETOT will be mostly due to
–IP
+IP
–ETOT
Figure 2: Total Output Error versus Sensed Current
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High-Accuracy, Hall-Effect-Based Current Sensor IC
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ACS724KMA
APPLICATION INFORMATION
Estimating Total Error versus Sensed Current
The Performance Characteristics tables give distribution
(±3 sigma) values for Total Error at IPR(max); however, one often
wants to know what error to expect at a particular current. This
can be estimated by using the distribution data for the components of Total Error, Sensitivity Error, and Offset Voltage. The
±3 sigma value for Total Error (ETOT) as a function of the sensed
current (IP) is estimated as:
2
ETOT(IP) = ESENS +
(
2
)
100 × VOE
Sens × IP
Here, ESENS and VOE are the ±3 sigma values for those error
terms. If there is an average sensitivity error or average offset
voltage, then the average Total Error is estimated as:
ETOTAVG (IP) = ESENSAVG +
100 × VOEAVG
Sens × IP
The resulting total error will be a sum of ETOT and ETOT_AVG.
Using these equations and the 3 sigma distributions for Sensitivity Error and Offset Voltage, the Total Error versus sensed current
(IP) is shown here for the ACS724KMATR-20AB. As expected,
as one goes towards zero current, the error in percent goes
towards infinity due to division by zero (refer to Figure 3).
20
Total Error (% of current measured)
15
10
5
–40ºC +3σ
–40ºC –3σ
0
25ºC +3σ
25ºC –3σ
–5
85ºC +3σ
85ºC –3σ
–10
–15
–20
0
5
10
15
20
25
Current (A)
Figure 3: Predicted Total Error as a Function of Sensed
Current for the ACS724KMATR-20AB
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ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
Thermal Rise vs. Primary Current
The thermal capacity of the ACS724 should be verified by the end
user in the application’s specific conditions. The maximum junction temperature, TJ(MAX) (165℃), should not be exceeded. Further
information on this application testing is available in the DC and
Transient Current Capability application note on the Allegro website.
The thermal response is highly dependent on PCB layout, copper
thickness, cooling techniques, and the profile of the injected current.
The current profile includes peak current, current “on-time”, and
duty cycle. While the data presented in this section was collected
with Direct-Current (DC) these numbers may be used to approximate
thermal response for both AC signals and current pulses.
ASEK724 Evaluation Board Layout
Self-heating due to the flow of current should be considered during
the design of any current sensing system. The sensor, printed circuit
board (PCB) and contacts to the PCB will generate heat as current
moves through the system.
The plot in Figure 4 shows the measured rise in steady-state die
temperature of the ACS724 versus continuous current at an ambient temperature, TA, of 25 °C. The thermal offset curves may be
directly applied to other values of TA. Conversely, Figure 5 shows
the maximum continuous current at a given TA. Surges beyond the
maximum current listed in Figure 5 are allowed given the maximum
junction temperature, TJ(MAX) (165℃), is not exceeded.
Thermal data shown in Figure 4 and Figure 5 was collected using
the ASEK724 Evaluation Board (TED-85-0815-003). This board
includes 1500 mm2 of 4 oz. copper (0.1388 mm) connected to pins
1 through 4, and to pins 5 through 8, with thermal vias connecting
the layers. Top and Bottom layers of the PCB are shown below in
Figure 6 .
Figure 4: Self Heating in the
MA Package Due to Current Flow
Figure 6: Top and Bottom Layers for
ASEK724 Evaluation Board
Gerber files for the ASEK724 evaluation board are available for
download from our website. Please see the technical documents
section of the ACS724 device webpage.
Figure 5: Maximum Continuous Current
at a Given TA
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High-Accuracy, Hall-Effect-Based Current Sensor IC
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ACS724KMA
NOT TO SCALE
All dimensions in millimeters.
15.75
9.54
0.65
1.27
Package Outline
Slot in PCB to maintain >8 mm creepage
once part is on PCB
2.25
7.25
1.27
3.56
17.27
Current
Out
Current
In
21.51
Perimeter holes for stitching to the other,
matching current trace design, layers of
the PCB for enhanced thermal capability.
Figure 7: High-Isolation PCB Layout
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High-Accuracy, Hall-Effect-Based Current Sensor IC
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ACS724KMA
PACKAGE OUTLINE DRAWING
For Reference Only – Not for Tooling Use
(Reference MS-013AA)
NOT TO SCALE
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
8°
0°
10.30 ±0.20
16
0.33
0.20
D
D2
D
D1
7.50 ±0.10
10.30 ±0.33
A
1
1.27 1.40 REF
0.40
2
0.78
Branded Face
D
0.25 BSC
SEATING PLANE
16X
C
2.65 MAX
0.10
C
GAUGE PLANE
SEATING
PLANE
0.30
0.10
1.27 BSC
0.51
0.31
0.65
1.27
16
NNNNNNN
LLLLLLLL
2.25
1
9.50
1
C
2
PCB Layout Reference View
B
Standard Branding Reference View
A
Terminal #1 mark area
B
Branding scale and appearance at supplier discretion
N = Device part number
L = Assembly Lot Number, first eight characters
C Reference land pattern layout (reference IPC7351 SOIC127P600X175-8M);
all pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary
to meet application process requirements and PCB layout tolerances
D Hall elements (D1, D2); not to scale
Figure 8: Package MA, 16-Pin SOICW
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ACS724KMA
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
Revision History
Number
Date
Description
–
December 11, 2015
1
January 8, 2016
Added ACS724KMATR-65AB-T variant
2
March 18, 2016
Added ACS724KMATR-30AB-T variant, UL/TUV certification; removed solder balls reference in Description
Initial release
3
April 13, 2016
Corrected Package Outline Drawing branding information (page 17).
4
June 15, 2017
Added ACS724KMATR-12AB-T variant; corrected packing information
5
November 27, 2017
6
January 12, 2018
Added Dielectric Surge Strength Test Voltage to Isolation Characteristics table (page 3).
7
January 22, 2018
Added Common Mode Field Rejection Ratio characteristic (page 5).
Added Sensitivity Ratiometry Coefficient and Zero-Current Output Ratiometry Coefficient to Electrical
Characteristics table (page 5).
8
June 22, 2018
9
December 18, 2018
Added Typical Frequency Response plots (page 15).
10
January 15, 2019
11
June 3, 2019
Updated TUV certificate mark
12
July 25, 2019
Updated Isolation Characteristics and Thermal Characteristics tables (page 3); added ESD Ratings table (page 3)
and Application Information section (page 20).
13
September 9, 2019
Updated certificate numbers
Added ACS724KMATR-65AB-T plots (page 15).
Added Hall plate dimensions (page 22).
14
March 5, 2020
Added Maximum Current to Absolute Maximum Ratings table (page 3); updated Isolation Characteristics Table
(page 3); added ESD Ratings Table (page 3); updated Rise Time, Response Time, Propagation Delay, and Output
Slew Rate test conditions (page 5); added Primary Conductor Inductance and Output Slew Rate values (page 5);
updated Typical Frequency Response (page 11); added Response Characteristics Definitions and Performance
Data application note (page 12); added Power On Functional Description and Performance Data (page 13); added
thermal data section (page 16)
15
May 27, 2020
Added Surge Strength Test Current to Isolation Characteristics table and updated Clearance value (page 3);
Added -50AB variant (pages 2, 10)
16
July 14, 2020
Corrected test conditions for -50AB variant performance characteristics (page 10)
17
August 18, 2020
Corrected Total Output Error maximum values (page 10)
18
February 5, 2021
Updated Total Output Error, Sensitivity Error, and Voltage Output Error test conditions (page 10) and Functional
Block Diagram (page 4)
Copyright 2021, Allegro MicroSystems.
Allegro MicroSystems reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit
improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the
information being relied upon is current.
Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of
Allegro’s product can reasonably be expected to cause bodily harm.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems assumes no responsibility for its use; nor
for any infringement of patents or other rights of third parties which may result from its use.
Copies of this document are considered uncontrolled documents.
For the latest version of this document, visit our website:
www.allegromicro.com
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