ACS711
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for <100 V Isolation Applications
Features and Benefits
Description
▪ No external sense resistor required; single package solution
▪ Reduced Power Loss:
▫0.6 mΩ internal conductor resistance on EX package
▫1.2 mΩ internal conductor resistance on LC package
▪ Economical low- and high-side current sensing
▪ Output voltage proportional to AC or DC currents
▪ ±12.5 A and ±25 A full scale sensing ranges on LC package
▪ ±15.5 A and ±31 A full scale sensing ranges on EX package
¯ Ā¯ Ū¯ L̄¯ T̄¯ trips and latches at 100% of full-scale current
▪ Overcurrent F̄
▪ Low-noise analog signal path
▪ 100 kHz bandwidth
▪ Small footprint, low-profile SOIC8 and QFN packages
▪ 3.0 to 5.5 V, single supply operation
▪ Integrated electrostatic shield for output stability
▪ Factory-trimmed for accuracy
▪ Extremely stable output offset voltage
▪ Zero magnetic hysteresis
▪ Ratiometric output from supply voltage
Packages:
8-pin SOICN
with internally fused path
(LC package)
The Allegro™ ACS711 provides economical and precise
solutions for AC or DC current sensing in <100 V audio,
communications systems, and white goods. The device package
allows for easy implementation by the customer. Typical
applications include circuit protection, current monitoring,
and motor and inverter control.
The device consists of a 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. Device accuracy is
optimized through the close proximity of the magnetic signal
to the Hall transducer.
The output of the device has a positive slope proportional to
the current flow from IP+ to IP– (pins 1 and 2, to pins 3 and
4). The internal resistance of this conductive path is 0.6 mΩ
for the EX package, and 1.2 mΩ for the LC package, providing
a non-intrusive measurement interface that saves power in
applications that require energy efficiency.
The ACS711 is optimized for low-side current sensing
applications, although the terminals of the conductive path
are electrically isolated from the sensor IC leads, providing
sufficient internal creepage and clearance dimensions for a
low AC or DC working voltage applications. The thickness
12-contact QFN
3 mm × 3 mm × 0.75 mm
(EX package)
Continued on the next page…
Approximate Scale 1:1
Typical Application
+3.3 V
IP+
VCC
CBYP
0.1 μF
IP+
VIOUT
IP
ACS711
IP–
IP–
RPU
CLOAD
FAULT
GND
Application 1. The ACS711 outputs an analog signal, VIOUT , that varies linearly with the
bi-directional AC or DC primary current, IP , within the range specified. The F̄¯ Ā Ū¯L̄¯ T̄¯ pin trips
when IP reaches ±100% of its full-scale current.
ACS711A-DS, Rev. 3
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Description (continued)
of the copper conductor allows survival of the device at up to 5×
overcurrent conditions.
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.
The ACS711 is provided in small, surface mount packages: SOIC8
and QFN12. The leadframe is plated with 100% matte tin, which
is compatible with standard lead (Pb) free printed circuit board
Selection Guide
TA
(°C)
Part Number
ACS711ELCTR-12AB-T
–40 to 85
ACS711KLCTR-12AB-T
–40 to 125
ACS711ELCTR-25AB-T
–40 to 85
ACS711KLCTR-25AB-T
–40 to 125
ACS711EEXLT-15AB-T3
–40 to 85
ACS711KEXLT-15AB-T3
–40 to 125
ACS711EEXLT-31AB-T3
–40 to 85
ACS711KEXLT-31AB-T3
–40 to 125
Optimized Accuracy
Range, IP
(A)
Sensitivity2,
Sens (Typ)
(mV/A)
±12.5
Package
Packing1
8-pin SOICN
3000 pieces/reel
12-contact QFN with
fused current loop
1500 pieces/reel
110
±25
55
±15.5
90
±31
45
1Contact Allegro
for additional packing options.
measured with VCC = 3.3 V.
3QFN package not qualified for automotive applications.
2Sensitivity
Absolute Maximum Ratings
Characteristic
Supply Voltage
Symbol
Rating
Units
VCC
Notes
7
V
Reverse Supply Voltage
VRCC
–0.1
V
Output Voltage
VIOUT
7
V
Reverse Output Voltage
VRIOUT
–0.1
V
100
VAC peak
or VDC
7
V
Working Voltage for Basic Isolation
F̄¯ Ā Ū¯L̄¯ T̄¯ Pin Voltage
Overcurrent Transient Tolerance
Nominal Operating Ambient Temperature
Maximum Junction Temperature
Storage Temperature
VWORKING
Voltage applied between pins 1-4 and 5-8
VFAULT
IPOC
TA
1 pulse, 100 ms
100
A
Range E
–40 to 85
ºC
Range K
–40 to 125
ºC
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Functional Block Diagram
VCC
VCC
RPU
Master Current
Supply
Current Fault
Comparator
To all subcircuits
D
Power-on
Reset
IP+
Hall Current
Drive
IP−
240 kΩ
Reset
Sensitivity
Temperature
Coefficient Trim
Dynamic Offset
Cancellation
IP+
CBYP
FAULT
VIOUT
Signal
Recovery
CLOAD
Sensitivity
Trim
0 Ampere
Offset Adjust
IP−
GND
VCC
VIOUT
12
11
Pin-out Diagrams
1
8
VCC
NC
IP+
2
7
VIOUT
IP–
3
8
NC
IP–
3
6
FAULT
IP–
4
7
NC
IP–
4
5
GND
6
IP+
9
5
10 NC
2
GND
1
IP+
FAULT
IP+
EX Package
LC Package
Terminal List Table
Name
Number
EX
Description
LC
GND
5
5
Signal ground terminal
F̄¯ Ā Ū¯L̄¯ T̄¯ 6
6
Overcurrent fault; active low
IP–
3 and 4
3 and 4
Terminals for current being sensed; fused internally
IP+
1 and 2
1 and 2
Terminals for current being sensed; fused internally
NC
7, 8, 9, 10
–
No connection; connect to GND for optimal ESD performance.
VCC
12
8
Device power supply terminal
VIOUT
11
7
Analog output signal
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
COMMON OPERATING CHARACTERISTICS Valid across the full range of TA for the LC package and at TA = 25°C for the EX package,
VCC = 3.3 V, unless otherwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
3
3.3
5.5
V
–
4
5.5
mA
ELECTRICAL CHARACTERISTICS
Supply Voltage1
VCC
Supply Current
ICC
VCC = 3.3 V, output open
Output Capacitance Load
CLOAD
VIOUT to GND
–
–
1
nF
Output Resistive Load
RLOAD
VIOUT to GND
15
–
–
kΩ
Primary Conductor
Resistance
VIOUT Rise Time
Propagation Delay Time
Response Time
Internal
Bandwidth2
RIP
tr
EX package
–
0.6
–
mΩ
LC package, TA = 25°C
–
1.2
–
mΩ
IP = IPMAX, TA = 25°C, COUT = open
–
3.5
–
μs
tPROP
IP = IP(max), TA = 25°C, COUT = open
–
1.2
–
µs
tRESPONSE
IP = IP(max), TA = 25°C, COUT = open
–
4.6
–
µs
BWI
–3 dB, TA = 25°C
–
100
–
kHz
Nonlinearity
ELIN
Over full range of IP
–
±1
–
%
Symmetry
ESYM
Apply full scale IP
VIOUT Saturation Voltages
Quiescent Output Voltage
Power-On Time
–
100
–
%
VIOH
VCC –
0.3
–
–
V
VIOL
–
–
0.3
V
IP = 0 A, TA = 25°C
–
VCC / 2
–
V
Output reaches 90% of steady-state level, TA = 25°C,
20 A present on primary conductor
–
35
–
μs
IFAULT
–
± 1 x IP
–
A
RPU
1
–
–
kΩ
VOH
–
VCC–
0.3
–
V
RPU = 1 kΩ
–
0.3
–
V
Measured from | IP | > | IFAULT | to VFAULT ≤ VOL
–
1.3
–
µs
VIOUT(Q)
tPO
¯ Ā ¯ T̄
¯ Pin Characteristics
F̄
Ū¯L̄
¯ Ā ¯ T̄
¯ Operating Point
F̄
Ū¯L̄
¯ Ā ¯ T̄
¯ Output Pullup
F̄
Ū¯L̄
Resistor
¯ Ā ¯ T̄
¯ Output Voltage
F̄
Ū¯L̄
VOL
F̄¯ Ā Ū¯L̄¯ T̄¯ Response Time
tFAULT
VCC Off Voltage Level for
Fault Reset3
VCCFR
–
–
200
mV
VCC Off Duration for
Fault Reset3
tCCFR
100
–
–
µs
1Devices are programmed for maximum accuracy at 3.3 V V
CC levels. The device contains ratiometry circuits that accurately alter the 0 A Output
Voltage and Sensitivity level of the device in proportion to the applied VCC level. However, as a result of minor nonlinearities in the ratiometry circuit
additional output error will result when VCC varies from the 3.3 V VCC level. Customers that plan to operate the device from a 5 V regulated supply
should contact their local Allegro sales representative regarding expected device accuracy levels under these bias conditions.
2Calculated using the formula BW = 0.35 / t .
I
r
3After the F̄
¯ Ā Ū¯L̄¯ T̄¯ pin is latched low, the only way to reset it is through a power-off and power-on cycle on the VCC pin. For fault reset, VCC must stay
below VCCFR for a period greater than tCCFR before settling to the normal operation voltage (3 to 5.5 V).
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
x12AB PERFORMANCE CHARACTERISTICS for LC package and E Temperature Range1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Total Output Error3
Symbol
Test Conditions
IP
Min.
Typ.
Max.
Units
–12.5
–
12.5
A
Over full range of IP
–
110
–
mV/A
Full scale of IP applied for 5 ms, TA = –40°C to 25°C
–
110
–
mV/A
Full scale of IP applied for 5 ms, TA = 25°C to 85°C
–
110
–
mV/A
VNOISE
TA = 25°C, no external low pass filter on VIOUT
–
11
–
mV
VOE(TA)
IP = 0 A, TA = 25°C
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TA = 25°C to 85°C
–
±40
–
mV
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
–
±50
–
mV
–
±5
–
%
Units
Sens
ETOT
IP = ±12.5 A,TA = –40°C to 85°C
1See
Characteristic Performance Data for parameter distributions over temperature.
2±3 sigma noise voltage.
3Percentage of I , with I = ±12.5 A.
P
P
x12AB PERFORMANCE CHARACTERISTICS for LC package and K Temperature Range1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Total Output Error3
Symbol
Test Conditions
Min.
Typ.
Max.
–12.5
–
12.5
A
Over full range of IP
–
110
–
mV/A
Full scale of IP applied for 5 ms, TA = –40°C to 25°C
–
110
–
mV/A
Full scale of IP applied for 5 ms, TA = 25°C to 125°C
–
110
–
mV/A
VNOISE
TA = 25°C, no external low pass filter on VIOUT
–
11
–
mV
VOE(TA)
IP = 0 A, TA = 25°C
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TA = 25°C to 125°C
–
±40
–
mV
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
–
±50
–
mV
–
±5
–
%
Units
IP
Sens
ETOT
IP = ±12.5 A,TA = –40°C to 125°C
1See
Characteristic Performance Data for parameter distributions over temperature.
2±3 sigma noise voltage.
3Percentage of I , with I = ±12.5 A.
P
P
x15AB PERFORMANCE CHARACTERISTICS1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Total Output Error3
Symbol
Test Conditions
Min.
Typ.
Max.
–15.5
–
15.5
A
Across full range of IP
–
90
–
mV/A
VNOISE
No external low pass filter on VIOUT
–
11
–
mV
VOE(TA)
IP = 0 A
–
±5
–
mV
IP
Sens
VOE(TOP)HT IP = 0 A, TA = 25°C to TA(max)
–
±40
–
mV
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
–
±50
–
mV
–
±5
–
%
ETOT
IP = ±12.5 A,TA = –40°C to TA(max)
1See
Characteristic Performance Data for parameter distributions across the full temperature range.
2±3 sigma noise voltage.
3Percentage of I , with I = ±15.5 A.
P
P
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
x25AB PERFORMANCE CHARACTERISTICS for for LC package and E Temperature Range1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Total Output Error3
Symbol
Test Conditions
IP
Min.
Typ.
Max.
Units
–25
–
25
A
Over full range of IP
–
55
–
mV/A
Full scale of IP applied for 5 ms, TA = –40°C to 25°C
–
55
–
mV/A
Full scale of IP applied for 5 ms, TA = 25°C to 85°C
–
55
–
mV/A
VNOISE
TA = 25°C, no external low pass filter on VIOUT
–
8
–
mV
VOE(TA)
IP = 0 A, TA = 25°C
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TA = 25°C to 85°C
–
±30
–
mV
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
–
±35
–
mV
–
±4
–
%
Min.
Typ.
Max.
Units
–25
–
25
A
Over full range of IP
–
55
–
mV/A
Full scale of IP applied for 5 ms, TA = –40°C to 25°C
–
55
–
mV/A
Full scale of IP applied for 5 ms, TA = 25°C to 125°C
–
55
–
mV/A
VNOISE
TA = 25°C, no external low pass filter on VIOUT
–
8
–
mV
VOE(TA)
IP = 0 A, TA = 25°C
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TA = 25°C to 125°C
–
±30
–
mV
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
–
±35
–
mV
–
±4
–
%
Min.
Typ.
Max.
Units
–31
–
31
A
Across full range of IP
–
45
–
mV/A
VNOISE
No external low pass filter on VIOUT
–
8
–
mV
VOE(TA)
IP = 0 A
–
±5
–
mV
–
±30
–
mV
–
±35
–
mV
–
±4
–
%
Sens
ETOT
IP =±25 A, TA = –40°C to 85°C
1See
Characteristic Performance Data for parameter distributions over temperature.
2±3 sigma noise voltage.
3Percentage of I , with I = ±25 A.
P
P
x25AB PERFORMANCE CHARACTERISTICS for LC package and K Temperature Range1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Total Output Error3
Symbol
Test Conditions
IP
Sens
ETOT
IP =±25 A, TA = –40°C to 125°C
1See
Characteristic Performance Data for parameter distributions over temperature.
2±3 sigma noise voltage.
3Percentage of I , with I = ±25 A.
P
P
x31AB PERFORMANCE CHARACTERISTICS1
TA = 25°C and VCC = 3.3 V, unless otherwise specified
Characteristic
Optimized Accuracy Range
Sensitivity
Noise2
Electrical Offset Voltage
Symbol
Test Conditions
IP
Sens
VOE(TOP)HT IP = 0 A, TA = 25°C to TA(max)
VOE(TOP)LT IP = 0 A, TA = –40°C to 25°C
Total Output Error3
ETOT
IP =±25 A, TA = –40°C to TA(max)
1See
Characteristic Performance Data for parameter distributions across the full temperature range.
2±3 sigma noise voltage.
3Percentage of I , with I = ±31 A.
P
P
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
ACS711
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
Thermal Characteristics
Characteristic
Package Thermal Resistance,
Junction to Lead
Package Thermal Resistance,
Junction to Ambient2
Symbol
RθJL
RθJA
Value
Units
LC package, mounted on Allegro ASEK 711 evaluation board
Test Conditions1
5
ºC/W
LC package, mounted on Allegro 85-0404 evaluation
board, includes the power consumed by the board
23
ºC/W
EX package, mounted on Allegro 85-0528 evaluation
board, includes the power consumed by the board
24
ºC/W
1Additional
thermal information available on the Allegro website
evaluation board has 1500 mm2 of 2 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. Further details on the board are available from the
Frequently Asked Questions document on our website.
2The Allegro
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Characteristic Performance Data
Data taken using the ACS711KLC-12A, VCC = 3.3 V
Accuracy Data
Electrical Offset Voltage versus Ambient Temperature
114
60
113
Sens (mV/A)
80
40
VOE (mV)
Sensitivity versus Ambient Temperature
20
0
112
111
110
-20
109
-40
108
-60
–60
–40
–20
0
20
40
60
80
100
120
107
–60
140
–40
–20
0
20
TA (°C)
Nonlinearity versus Ambient Temperature
101.5
1.5
101.0
ESYM (%)
ELIN (%)
1.0
0.5
0
100
120
140
100.5
100.0
99.0
-1.0
-1.5
–40
–20
0
20
40
60
80
100
120
98.5
–60
140
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
TA (°C)
Total Output Error versus Ambient Temperature
Fault Operating Point versus Ambient Temperature
8
16
6
14
4
12
2
IFAULT(A)
ETOT (%)
80
99.5
-0.5
0
-2
10
8
6
4
-4
-6
–60
60
Symmetry versus Ambient Temperature
2.0
–60
40
TA (°C)
2
–40
–20
0
20
40
60
80
100
120
0
140
–60
TA (°C)
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Characteristic Performance Data
Data taken using the ACS711KLC-25A, VCC = 3.3 V
Accuracy Data
Electrical Offset Voltage versus Ambient Temperature
40
57.0
30
56.5
Sens (mV/A)
20
VOE (mV)
Sensitivity versus Ambient Temperature
10
0
-10
55.5
55.0
54.5
-20
54.0
-30
-40
–60
56.0
–40
–20
0
20
40
60
80
100
120
53.5
–60
140
–40
–20
0
20
TA (°C)
Nonlinearity versus Ambient Temperature
120
140
100.4
0.5
ESYM (%)
ELIN (%)
100
100.6
0
-0.5
100.2
100.0
99.8
99.6
99.4
-1.0
99.2
99.0
–40
–20
0
20
40
60
80
100
120
140
–60
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
TA (°C)
Total Output Error versus Ambient Temperature
Fault Operating Point versus Ambient Temperature
5
30
4
25
3
2
20
1
IFAULT (A)
ETOT (%)
80
100.8
1.0
0
-1
-2
15
10
5
-3
-4
–60
60
Symmetry versus Ambient Temperature
1.5
-1.5
–60
40
TA (°C)
–40
–20
0
20
40
60
80
100
120
0
140
–60
TA (°C)
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Characteristic Performance Data
Data taken using the ACS711KLC-25A
Timing Data
Rise Time
Propagation Delay Time
VIOUT (0.5 V/div.)
VIOUT (0.5 V/div.)
IP (10 A/div.)
IP (10 A/div.)
3.47 µs
1.24 µs
t (2 µs/div.)
t (2 µs/div.)
Response Time
Fault Response
VIOUT (0.5 V/div.)
IP (10 A/div.)
4.62 µs
IP (10 A/div.)
1.28 µs
Fault (2 V/div.)
t (2 µs/div.)
t (2 µs/div.)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
ACS711
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
Definitions of Accuracy Characteristics
Sensitivity (Sens). The change in sensor output in response to a
1 A change through the primary conductor. The sensitivity is the
product of the magnetic circuit sensitivity (G / A) 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.
Noise (VNOISE). The product of the linear IC amplifier gain (mV)
and the noise floor for the Allegro Hall effect linear IC. The noise
floor is derived from the thermal and shot noise observed in Hall
elements. Dividing the noise (mV) by the sensitivity (mV/A) provides the smallest current that the device is able to resolve. Linearity (ELIN). The degree to which the voltage output from
the sensor varies in direct proportion to the primary current
through its full-scale amplitude. Nonlinearity in the output can be
attributed to the saturation of the flux concentrator approaching
the full-scale current. The following equation is used to derive the
linearity: { [
100 1–
∆ gain × % sat ( VIOUT_full-scale amperes – VIOUT(Q) )
2 (VIOUT_half-scale amperes – VIOUT(Q) )
Accuracy (ETOT). The accuracy represents the maximum deviation of the actual output from its ideal value. This is also known
as the total ouput error. The accuracy is illustrated graphically in
the output voltage versus current chart below.
Ratiometry. The ratiometric feature means that its 0 A output,
VIOUT(Q), (nominally equal to VCC/2) and sensitivity, Sens, are
proportional to its supply voltage, VCC . The following formula is
used to derive the ratiometric change in 0 A output voltage,
ΔVIOUT(Q)RAT (%):
100
VIOUT(Q)VCC / VIOUT(Q)3.3V
The ratiometric change in sensitivity, ΔSensRAT (%), is defined as:
100
[{
SensVCC / Sens3.3V
VCC / 3.3 V
Accuracy at 0 A and at Full-Scale Current
Increasing VIOUT(V)
Symmetry (ESYM). The degree to which the absolute voltage
output from the sensor varies in proportion to either a positive
or negative full-scale primary current. The following formula is
used to derive symmetry:
VIOUT_+ full-scale amperes – VIOUT(Q)
VIOUT(Q) – VIOUT_–full-scale amperes
Electrical offset voltage (VOE). The deviation of the device output from its ideal quiescent value of VCC / 2 due to nonmagnetic
causes. To convert this voltage to amperes, divide by the device
sensitivity, Sens.
Accuracy
Over ∆Temp erature
Accuracy
25°C Only
Average
VIOUT
Quiescent output voltage (VIOUT(Q)). The output of the sensor
when the primary current is zero. For a unipolar supply voltage,
it nominally remains at VCC ⁄ 2. Thus, 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.
Output Voltage versus Sensed Current
where VIOUT_full-scale amperes = the output voltage (V) when the
sensed current approximates full-scale ±IP .
100
VCC / 3.3 V
Accuracy
Over ∆Temp erature
IP(min)
Accuracy
25°C Only
–IP (A)
+IP (A)
Full Scale
IP(max)
0A
Accuracy
25°C Only
Accuracy
Over ∆Temp erature
Decreasing VIOUT(V)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
11
ACS711
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
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.
Rise time (tr). 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 rise time to a step response is used to
derive the bandwidth of the current sensor, 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.
I (%)
Primary Current
90
Transducer Output
10
0
Rise Time, tr
t
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Application Information
Layout
To optimize thermal and electrical performance, the
following features should be included in the printed
circuit board:
•The primary leads should be connected to as much
copper area as is available.
•The copper should be 2 oz. or heavier.
•Additional layers of the board should be used for
conducting the primary current if possible, and
should be connected using the arrangement of vias
shown below.
•The two solder pads at the ends of the exposed pad
loop should be placed directly on the copper trace
that conducts the primary current.
•When using vias under exposed pads, such as with
the EX package, using plugged vias prevents wicking
of the solder from the pad into the via during reflow.
Whether or not to use plugged vias should be evaluated in the application.
Solder pads
Signal traces
EX package
footprint
Exposed pad loop
Via under pad
Via
Primary Current Trace
Primary Current Trace
Suggested Layout. EX package shown.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Package LC, 8-pin SOIC
4.90 ±0.10
8°
0°
8
0.65
3.90 ±0.10
1
6.00 ±0.20
2
0.25 BSC
Branded Face
SEATING
PLANE
0.10 C
0.51
0.31
1.27 BSC
5.60
1.04 REF
1
1.27
0.40
8X
C
1.27
1.75
0.25
0.17
A
8
C
2
PCB Layout Reference View
SEATING PLANE
GAUGE PLANE
NNNNNNN
TPP-AAA
LLLLL
1.75 MAX
0.25
0.10
1
B Standard Branding Reference View
For Reference Only; not for tooling use (reference MS-012AA)
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
A Terminal #1 mark area
B Branding scale and appearance at supplier discretion
C
D
N = Device part number
T = Device temperature range
P = Package Designator
A = Amperage
L = Lot number
Belly Brand = Country of Origin
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
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Package EX, 12-Contact QFN
With Fused Sensed Current Loop
3.00 BSC
0.85
12
1
1.27
MIN
0.30
12
1
A
2
3.00 BSC
2.90
1.00
0.80
MIN
Branded Face
9X
0.50
D
SEATING
PLANE
0.08 C
0.50 BSC
C
0.70
2.05 REF
0.75 ±0.05
C
2.70
PCB Layout Reference View
+0.05
0.25 –0.07
1
1.79
0.40±0.10
B
0.20
NNNN
YYWW
LLLL
2
1
E
12
For reference only, not for tooling use (reference JEDEC MO-220WEED
except for fused current path)
Dimensions in millimeters
Exact case and lead configuration at supplier discretion within limits shown
A Terminal #1 mark area
B Fused sensed current path
Standard Branding Reference View
N = Device part number
Y = Last two digits of year of manufacture
W = Week of manufacture
L = Lot number
C Reference land pattern layout (reference IPC7351
QFN50P300X300X80-17W4M);
All pads a minimum of 0.20 mm from all adjacent pads; adjust as
necessary to meet application process requirements and PCB layout
tolerances; when mounting on a multilayer PCB, thermal vias at the
exposed thermal pad land can improve thermal dissipation (reference
EIA/JEDEC Standard JESD51-5)
D Coplanarity includes exposed current path and terminals
E
Branding scale and appearance at supplier discretion
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
15
Hall Effect Linear Current Sensor with Overcurrent
Fault Output for < 100 V Isolation Applications
ACS711
Revision History
Revision No.
Revision Date
2
July 18, 2013
Description of Revision
3
February 6, 2015
Update characteristics tables references
Revised NC description in Terminal List Table
Copyright ©2008-2015, Allegro MicroSystems, LLC
Allegro MicroSystems, LLC 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 life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no responsibility for its
use; nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, visit our website:
www.allegromicro.com
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
16