ACS725KMA Datasheet by Allegro MicroSystems

View All Related Products | Download PDF Datasheet
5 [2“ US Mm J ; 4'1 I IIH
The Allegro ACS725KMA 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, chopper-stabilized 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.
The terminals of the conductive path are electrically isolated
from the sensor leads (pins 9 through 16). This allows the
ACS725KMA current sensor IC to be used in high-side current
ACS725KMA-DS, Rev. 11
MCO-0000218
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 space-
constrained applications
3 to 3.6 V single supply operation
Output voltage proportional to AC or DC current
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
Continued on the next page…
Package: 16-pin SOICW (suffix MA)
Typical Application
1
5
2
6
3
7
4
8
+I
P
IP
CL
CBYPASS
0.1 µF
–I
P
IP+
IP+
IP+
IP+
IP–
IP–
IP–
IP–
NC
GND
NC
FILTER
VIOUT
NC
VCC
NC 9
10
11
12
13
14
15
16
ACS725KMA
CF
1 nF
The ACS725KMA outputs
an analog signal, VIOUT , that
changes proportionally with
the bidirectional AC or DC
primary sensed current, IP ,
within the specified measure-
ment range.
The FILTER pin can be used
to decrease the bandwidth in
order to optimize the noise
performance.
Continued on the next page…
FEATURES AND BENEFITS DESCRIPTION
CB Certificate Number:
US-32210-M1-UL
TÜV America
Certificate Number:
U8V 16 03 54214 040
CB 16 03 54214 039
Not to scale
ACS725KMA
September 9, 2019
‘ LLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
2
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
sense applications without the use of high-side differential amplifiers
or other costly isolation techniques.
The ACS725KMA 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.
DESCRIPTION (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
FEATURES AND BENEFITS (continued)
SELECTION GUIDE
Part Number IPR (A) Sens(Typ) at VCC = 3.3 V
(mV/A) TA (°C) Packing [1]
ACS725KMATR-20AB-T ±20 66
–40 to 125 Tape and Reel, 1000 pieces per reelACS725KMATR-30AB-T ±30 44
ACS725KMATR-30AU-T 30 88
[1] Contact Allegro for additional packing options.
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
3
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
ISOLATION CHARACTERISTICS
Characteristic Symbol Notes Rating Unit
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). 10000 V
Dielectric Strength Test Voltage 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
Working Voltage for Basic Isolation VWVBI Maximum approved working voltage for basic (single) isolation
according to UL 60950-1 (edition 2).
1550 VPK
1097 VRMS or VDC
Working Voltage for Reinforced Isolation VWVRI Maximum approved working voltage for reinforced isolation
according to UL 60950-1 (edition 2).
800 VPK
565 VRMS or VDC
Clearance Dcl Minimum distance through air from IP leads to signal leads. 7.5 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
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
Operating Ambient Temperature TARange K –40 to 125 °C
Junction Temperature TJ(max) 165 °C
Storage Temperature Tstg –65 to 165 °C
SPECIFICATIONS
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
THERMAL CHARACTERISTICS
[1]
Characteristic Symbol Test Conditions Value Unit
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] 23 °C/W
Junction-to-Lead Thermal Resistance RθJL Mounted on the Allegro ASEK724/5 MA evaluation board. [2] 5°C/W
[1] Refer to the die temperature curves versus DC current plot (page 16). Additional thermal information is available on the Allegro website.
[2] The Allegro evaluation board has 1500 mm2 of 2 oz. copper on each side, connected to pins 1 through 4 and pins 5 through 8, with thermal vias con-
necting 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.
33333333 CEECEEEE mmmsystems .0 R G E L L A
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
4
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Terminal List Table
Number Name Description
1, 2, 3, 4 IP+ Terminals for current being sensed; fused internally
5, 6, 7, 8 IP- Terminals for current being sensed; fused internally
9, 16 NC No internal connection; recommended to be left unconnected in order to
maintain high creepage
10 VCC Device power supply terminal
11, 14 NC No internal connection; recommened to connect to GND for the best ESD
performance
12 VIOUT Analog output signal
13 FILTER Terminal for external capacitor that sets bandwidth
15 GND Signal ground terminal
Functional Block Diagram
Pinout Diagram
Dynamic Offset
Cancellation
Master Current
Supply Programming
Control
EEPROM and
Control Logic
Offset
Control
Sensitivity
Control
Temperature
Sensor
Hall
Current
Drive
POR
To All Subcircuits
IP+
IP+
IP
IP
VCC
VCC
VIOUT
CBYPASS
0.1 µF
FILTER
RF(int)
GND CF
+
+
IP+
IP+
IP
IP
1
IP+
2
IP+
3
IP+
4
IP+
5
IP-
6
IP-
7
IP-
8
IP-
9NC
10 VCC
11 NC
12 VIOUT
13 FILTE
R
14 NC
15 GND
16 NC
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
5
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Supply Voltage VCC 3 3.3 3.6 V
Supply Current ICC VCC within VCC(min) and VCC(max) 10 14 mA
Output Capacitance Load CLVIOUT to GND 10 nF
Output Resistive Load RLVIOUT to GND 4.7 kΩ
Primary Conductor Resistance RIP TA = 25°C 0.85 mΩ
Internal Filter Resistance [2] RF(INT) 1.7 kΩ
Common Mode Field Rejection Ratio CMFRR 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
Hall Plate Sensitivity Matching SensMATCH TA = 25°C ±1 %
Hysteresis IHYS Difference in offset after a ±40 A pulse 150 mA
Rise Time trIP = IP(max), TA = 25°C, CL = 1 nF 3 μs
Propagation Delay tpd IP = IP(max), TA = 25°C, CL = 1 nF 2 μs
Response Time tRESPONSE IP = IP(max), TA = 25°C, CL = 1 nF 4 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 618 µARMS/
Hz
Noise INInput-referenced noise; CF = 4.7 nF,
CL = 1 nF, BW = 18 kHz, TA = 25°C 91 mARMS
Nonlinearity ELIN Through full range of IP– ±1 %
Sensitivity Ratiometry Coefficient SENS_RAT_
COEF VCC = 3.0 to 3.6 V, TA = 25°C 1.3
Zero-Current Output Ratiometry Coefficient QVO_RAT_
COEF VCC = 3.0 to 3.6 V, TA = 25°C 1
Saturation Voltage [3] VOH RL = 4.7 kΩ, TA = 25°C VCC – 0.3 V
VOL RL = 4.7 kΩ, TA = 25°C 0.3 V
Power-On Time 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
[1] Device may be operated at higher primary current levels, IP , ambient temperatures, TA , and internal leadframe temperatures, provided the Maximum Junction Tempera-
ture, TJ(max), is not exceeded.
[2] RF(INT) forms an RC circuit via the FILTER pin.
[3] The sensor IC will continue to respond to current beyond the range of IP until the high or low saturation voltage; however, the nonlinearity in this region will be worse than
through the rest of the measurement range.
COMMON ELECTRICAL CHARACTERISTICS [1]: Valid through the full range of TA = –40°C to 125°C
and
VCC
= 3.3 V, unless otherwise specified
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
6
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
xKMATR-20AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 3.3 V, unless
otherwise specified
Characteristic Symbol Test Conditions Min. Typ.[1] Max. Units
NOMINAL PERFORMANCE
Current Sensing Range IPR –20 – 20 A
Sensitivity Sens IPR(min) < IP < IPR(max) 66 mV/A
Zero Current Output Voltage VIOUT(Q) Bidirectional; IP = 0 A VCC ×
0.5 – V
ACCURACY PERFORMANCE
Total Output Error [2] ETOT
IP = IPR(max), TA = 25°C to 125°C –2.5 ±1 2.5 %
IP = IPR(max), TA = –40°C to 25°C ±3 %
TOTAL OUTPUT ERROR COMPONENTS [3]: ETOT = ESENS + 100 × VOE/(Sens × IP)
Sensitivity Error ESENS
TA = 25°C to 125°C, measured at IP = IPR(max) –2 ±1 2 %
TA = –40°C to 25°C, measured at IP = IPR(max) – ±2.5 %
Offset Voltage VOE
IP = 0 A, TA = 25°C to 125°C –15 ±6 15 mV
IP = 0 A, TA = –40°C to 25°C ±17 mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift Esens_drift – ±1 %
Total Output Error Lifetime Drift Etot_drift – ±1 %
[1] Typical values with +/- are 3 sigma values.
[2] 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.
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
7
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
xKMATR-30AB PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 3.3 V, unless
otherwise specified
Characteristic Symbol Test Conditions Min. Typ.[1] Max. Units
NOMINAL PERFORMANCE
Current Sensing Range IPR –30 – 30 A
Sensitivity Sens IPR(min) < IP < IPR(max) 44 mV/A
Zero Current Output Voltage VIOUT(Q) Bidirectional; IP = 0 A VCC ×
0.5 – V
ACCURACY PERFORMANCE
Total Output Error [2] ETOT
IP = IPR(max), TA = 25°C to 125°C –2.5 ±1 2.5 %
IP = IPR(max), TA = –40°C to 25°C ±2.5 %
TOTAL OUTPUT ERROR COMPONENTS [3]: ETOT = ESENS + 100 × VOE/(Sens × IP)
Sensitivity Error ESENS
TA = 25°C to 125°C, measured at IP = IPR(max) –2 ±1 2 %
TA = –40°C to 25°C, measured at IP = IPR(max) – ±2.4 %
Offset Voltage VOE
IP = 0 A, TA = 25°C to 125°C –15 ±5 15 mV
IP = 0 A, TA = –40°C to 25°C ±11 mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift Esens_drift – ±1 %
Total Output Error Lifetime Drift Etot_drift – ±1 %
[1] Typical values with +/- are 3 sigma values.
[2] 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.
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
8
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
xKMATR-30AU PERFORMANCE CHARACTERISTICS: TA Range K, valid at TA = – 40°C to 125°C, VCC = 3.3 V, unless
otherwise specified
Characteristic Symbol Test Conditions Min. Typ.[1] Max. Units
NOMINAL PERFORMANCE
Current Sensing Range IPR 0 – 30 A
Sensitivity Sens IPR(min) < IP < IPR(max) 88 mV/A
Zero Current Output Voltage VIOUT(Q) Unidirectional; IP = 0 A VCC ×
0.1 – V
ACCURACY PERFORMANCE
Total Output Error [2] ETOT
IP = IPR(max), TA = 25°C to 125°C –2.5 ±1.25 2.5 %
IP = IPR(max), TA = –40°C to 25°C ±2.5 %
TOTAL OUTPUT ERROR COMPONENTS [3]: ETOT = ESENS + 100 × VOE/(Sens × IP)
Sensitivity Error ESENS
TA = 25°C to 125°C, measured at IP = IPR(max) –2 ±1.2 2 %
TA = –40°C to 25°C, measured at IP = IPR(max) – ±2.5 %
Offset Voltage VOE
IP = 0 A, TA = 25°C to 125°C –15 ±10 15 mV
IP = 0 A, TA = –40°C to 25°C ±18 mV
LIFETIME DRIFT CHARACTERISTICS
Sensitivity Error Lifetime Drift Esens_drift – ±1 %
Total Output Error Lifetime Drift Etot_drift – ±1 %
[1] Typical values with +/- are 3 sigma values.
[2] 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.
3.5 wags, auto 35 BE EEEfi 35 BE .3": microsystems U R G E L I. A
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
9
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Average+3 Sigma -3 Sigma
CHARACTERISTIC PERFORMANCE
xKMATR-20AB
1625
1630
1635
1640
1645
1650
1655
1660
1665
1670
-50 0 50 100 150
VIOUT(Q) (mV)
Temperature (°C)
Zero Current Output Voltage vs. Temperature
-25
-20
-15
-10
-5
0
5
10
15
20
-50 0 50 100 150
Oset Voltage (mV)
Temperature (°C)
Oset Voltage vs. Temperature
64
64
65
65
66
66
67
67
68
-50 0 50 100 150
Sensitivity (mV/A)
Temperature (°C)
Sensitivity vs. Temperature
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
-50 0 50 100 150
Sensitivity Error (%)
Temperature (°C)
Sensitivity Error vs. Temperature
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
-50 0 50 100 150
Nonlinearity (%)
Temperature (°C)
Nonlinearity vs. Temperature
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
-50 0 50 100 150
Total Error (%)
Temperature (°C)
Total Error at IPR(max) vs. Temperature
Hf: + + Total Error (as) ALLEGRO" microsystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
10
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Average+3 Sigma -3 Sigma
CHARACTERISTIC PERFORMANCE
xKMATR-30AB
1635
1640
1645
1650
1655
1660
1665
-50 0 50 100 150
VIOUT(Q) (mV)
Temperature (°C)
Zero Current Output Voltage vs. Temperature
-15
-10
-5
0
5
10
15
-50 0 50 100 150
Oset Voltage (mV)
Temperature (°C)
Oset Voltage vs. Temperature
42
43
43
44
44
45
45
-50 0 50 100 150
Sensitivity (mV/A)
Temperature (°C)
Sensitivity vs. Temperature
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
-50 0 50 100 150
Sensitivity Error (%)
Temperature (°C)
Sensitivity Error vs. Temperature
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
-50 0 50 100 150
Nonlinearity (%)
Temperature (°C)
Nonlinearity vs. Temperature
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
-50 0 50 100 150
Temperature (°C)
Total Error at IPR(max) vs. Temperature
.25 $3.9 «3:0 35 BE EEEfi 3a 65 .33 microsystems U R G E L I. A
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
11
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Average+3 Sigma -3 Sigma
CHARACTERISTIC PERFORMANCE
xKMATR-30AU
305
310
315
320
325
330
335
340
345
350
-50 0 50 100 150
VIOUT(Q) (mV)
Temperature (°C)
Zero Current Output Voltage vs. Temperature
-25
-20
-15
-10
-5
0
5
10
15
20
-50 0 50 100 150
Oset Voltage (mV)
Temperature (°C)
Oset Voltage vs. Temperature
84
85
85
86
86
87
87
88
88
89
89
90
-50 0 50 100 150
Sensitivity (mV/A)
Temperature (°C)
Sensitivity vs. Temperature
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
-50 0 50 100 150
Sensitivity Error (%)
Temperature (°C)
Sensitivity Error vs. Temperature
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
-50 0 50 100 150
Nonlinearity (%)
Temperature (°C)
Nonlinearity vs. Temperature
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
-50 0 50 100 150
Total Error (%)
Temperature (°C)
Total Error at IPR(max) vs. Temperature
Phase ["1 Magnimde [dB] ACS724 Frequeney Response ‘ 710 10' so 102 103 10‘ Frequency [Hz] 105 7100 7 7150 10' 102 103 10‘ Frequency [Hz] 105 ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
12
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
CHARACTERISTIC PERFORMANCE
ACS724 TYPICAL FREQUENCY RESPONSE
10
1
10
2
10
3
10
4
10
5
Frequency [Hz]
-10
-5
0
5
Magnitude [dB]
ACS724 Frequency Response
10
1
10
2
10
3
10
4
10
5
Frequency [Hz]
-150
-100
-50
0
50
Phase [°]
I} H \crosystems éALLEmGRO'
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
13
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
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.
Nonlinearity (ELIN)
The nonlinearity is a measure of how linear the output of the sen-
sor IC is over the full current measurement range. The nonlinear-
ity is calculated as:
1
[{
[{
VIOUT
(IPR(max)) VIOUT(Q) × 100 (%)
ELIN = 2 × VIOUT
(IPR(max)/2) VIOUT(Q)
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.
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 =
3.3 V translates into VIOUT(Q) = 1.65 V. Variation in VIOUT(Q) can
be attributed to the resolution of the Allegro linear IC quiescent
voltage trim and thermal drift.
Offset Voltage (VOE)
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.
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:
E
TOT
(I
P
)
V
IOUT_ideal
(I
P
) – V
IOUT
(I
P
)
Sens
ideal
(I
P
)
×
I
P
×
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
DEFINITIONS OF ACCURACY CHARACTERISTICS
Figure 1: Output Voltage versus Sensed Current
Figure 2: Total Output Error versus Sensed Current
0 A
Decreasing
VIOUT (V)
Accuracy Across
Temperature
Accuracy Across
Temperature
Accuracy Across
Temperature
Accuracy at
25°C Only
Accuracy at
25°C Only
Accuracy at
25°C Only
Increasing
VIOUT (V)
Ideal VIOUT
IPR(min)
IPR(max)
+IP (A)
–IP (A)
VIOUT(Q)
Full Scale IP
+IP
–IP
+ETOT
–ETOT
Across Temperature
25°C Only
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 .
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
14
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
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 compo-
nents 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:
E(I) =
TOTP
100 × VOE
Sens × IP
E+
SENS
2()
2
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:
Sens × IP
E(I) = E+
TOTP SENS
AVGAVG
100 × VOEAVG
The resulting total error will be a sum of ETOT and ETOT_AVG.
Using these equations and the 3 sigma distributions for Sensitiv-
ity Error and Offset Voltage, the Total Error versus sensed current
(IP) is shown here for the ACS725KMATR-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).
Figure 3: Predicted Total Error as a Function of Sensed
Current for the ACS725KMATR-20AB
–20
–15
–10
–5
0
5
10
15
20
0 5 10 15 20 25
Total Error (% of current measured)
Current (A)
–40°C +3σ
–40°C –3σ
25°C +3σ
25°C –3σ
85°C +3σ
85°C –3σ
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
15
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
DEFINITIONS OF DYNAMIC RESPONSE CHARACTERISTICS
Power-On Time (tPO)
When the supply is ramped to its operating voltage, the device
requires a finite time to power its internal components before
responding to an input magnetic field.
Power-On Time (tPO) is defined as the time it takes for the output
voltage to settle within ±10% of its steady-state value under an
applied magnetic field, after the power supply has reached its
minimum specified operating voltage (VCC(min)) as shown in the
chart at right (refer to Figure 4).
Rise Time (tr)
The time interval between: a) when the sensor IC reaches 10%
of its full-scale value; and b) when it reaches 90% of its full-
scale value (refer to Figure 5). The rise time to a step response is
used to derive the bandwidth of the current sensor IC, in which
ƒ(–3 dB) = 0.35 / tr . Both tr and tRESPONSE are detrimentally
affected by eddy current losses observed in the conductive IC
ground plane.
Propagation Delay (tpd
)
The propagation delay is measured as the time interval between:
a) when the primary current signal reaches 20% of its final value,
and b) when the device reaches 20% of its output corresponding
to the applied current (refer to Figure 5).
Response Time (tRESPONSE)
The time interval between: a) when the primary current signal
reaches 90% of its final value, and b) when the device reaches
90% of its output corresponding to the applied current (refer to
Figure 6).
VIOUT
V
t
VCC
VCC(min)
90% VIOUT
0
t1= time at which power supply reaches
minimum specified operating voltage
t2=
time at which output voltage settles
within ±10% of its steady state value
under an applied magnetic field
t1t2
tPO
V
CC
(typ)
Primary Current
VIOUT
90
0
(%)
Response Time, tRESPONSE
t
Primary Current
VIOUT
90
10
20
0
(%)
Propagation Delay, tpd
Rise Time, tr
t
Figure 4: Power-On Time
Figure 5: Rise Time and Propagation Delay
Figure 6: Response Time
fiSEK721i5 Demo Board ALLEGRO' mwcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
16
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
APPLICATION INFORMATION
Thermal Rise vs. Primary Current
Self-heating due to the flow of current should be considered dur-
ing 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 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.
The plot in Figure 7 shows the measured rise in steady-state die
temperature of the ACS725KMA versus DC input current at an
ambient temperature, TA, of 25 °C. The thermal offset curves may
be directly applied to other values of TA.
0
20
40
60
80
100
120
140
0 20 40 60 80
Change in Die Temperature (°C)
DC Current (A)
Figure 7: Self-heating in the MA package
due to current flow
The thermal capacity of the ACS725KMA should be verified by
the end user in the application’s specific conditions. The maximum
junction temperature, TJ(MAX), should not be exceeded. Further
information on this application testing is available in the “DC and
Transient Current Capability” application note [1] on the Allegro
website.
[1] http://www.allegromicro.com/en/Design-Center/Technical-Documents/
Hall-Effect-Sensor-IC-Publications/DC-and-Transient-Current-Capability-Fuse-
Characteristics.aspx
[2] https://www.allegromicro.com/en/products/sense/current-sensor-ics/zero-to-
fifty-amp-integrated-conductor-sensor-ics/acs725ma
ASEK724/5 MA Evaluation Board Layout
Thermal data shown in Figure 7 was collected using the
ASEK724/5 MA Evaluation Board (TED-85-0815-002). This
board includes 1500 mm2 of 2 oz. (0.0694 mm) copper con-
nected 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 8.
Figure 8: Top and bottom layers for
ASEK724/5 MA evaluation board
Gerber files for the ASEK724/5 MA evaluation board are avail-
able for download from the Allegro website. See the technical
documents section of the ACS725xMA device webpage [2].
©©©©©© ©@ © © © © © © © © © W © © © @ ©© @ “HU©© © _ ©© @ " ©© Q " ©©©©©©©©©©© " ©©©©©©©©©©© " ©© @ _ ©© @ L|L©© © ©© © © © © © @ +© © © © © © © © ©©©©©© ©© mxcrosystems .0 D“ nu F— L L _A
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
17
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
7.25
2.25
3.56
1.27
1.27
0.65
15.75
9.54
17.27
21.51
Package Outline
Slot in PCB to maintain >8 mm creepage
once part is on PCB
Current
In
Current
Out
Perimeter holes for stitching to the other,
matching current trace design, layers of
the PCB for enhanced thermal capability.
NOT TO SCALE
All dimensions in millimeters.
Figure 9: High-Isolation PCB Layout
For Reference Only — Not for Tooling Use QQQQQQQQ m-g—Ilflflfllrfllflflg jrflf flflflflflflflfl ll ll ll ll ll ll ll ll A Standard Branding Reference Vxew flflflflifl H [mi é PCB Layou 1 Reference View A LLEGRO' mwcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
18
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Figure 10: Package MA, 16-Pin SOICW
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
C
1.27 BSC
A
B
C
21
16
Branding scale and appearance at supplier discretion
C
SEATING
PLANE
C0.10
16
X
0.25 BSC
1.40 REF
2.65 MAX
10.30 ±0.20
7.50 ±0.10 10.30 ±0.33
0.51
0.31
0.30
0.10
0.33
0.20
1.27
0.40
A
Branded Face
SEATING PLANE
GAUGE PLANE
Terminal #1 mark area
C
2
1
16
0.65 1.27
9.50
2.25
PCB Layout Reference View
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
B
1
Standard Branding Reference View
NNNNNNN
LLLLLLLL
= Device part number
= Assembly Lot Number, first eight characters
N
L
0.78
D
D
D
D2
D1
D Hall elements (D1, D2); not to scale
ALLEGRO' mxcrosystems
High-Accuracy, Hall-Effect-Based Current Sensor IC
with Common-Mode Field Rejection in High-Isolation SOIC16 Package
ACS725KMA
19
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
For the latest version of this document, visit our website:
www.allegromicro.com
Number Date Description
December 11, 2015 Initial release
1March 18, 2016 Added ACS725KMATR-30AB-T variant, UL/TUV certification; removed solder balls reference in Description
2June 15, 2017 Corrected Package Outline Drawing branding information; corrected packing information
3November 27, 2017 Added Sensitivity Ratiometry Coefficient and Zero-Current Output Ratiometry Coefficient to Electrical
Characteristics table (page 5).
4January 12, 2018 Added Dielectric Surge Strength Test Voltage to Isolation Characteristics table (page 3).
5January 22, 2018 Added Common Mode Field Rejection Ratio characteristic (page 5).
6June 22, 2018 Added Typical Frequency Response plots (page 12).
7September 25, 2018 Updated Noise and Noise Density values (page 5).
8December 18, 2018 Updated certificate numbers
9June 3, 2019 Updated TUV certificate mark
10 July 25, 2019 Updated Isolation Characteristics and Thermal Characteristics tables (page 3); added ESD Ratings table
(page 3) and Application Information section (page 16).
11 September 9, 2019 Added Hall plate dimensions (page 18).
Revision History
Copyright 2019, 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.

Products related to this Datasheet

SENSOR CURRENT HALL 20A AC/DC
SENSOR CURRENT HALL 30A AC/DC
SENSOR CURRENT HALL 30A DC