ACS758xCB
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
Features and Benefits
Description
▪ Industry-leading noise performance through proprietary
amplifier and filter design techniques
▪ Integrated shield greatly reduces capacitive coupling from
current conductor to die due to high dV/dt signals, and
prevents offset drift in high-side, high voltage applications
▪ Total output error improvement through gain and offset
trim over temperature
▪ Small package size, with easy mounting capability
▪ Monolithic Hall IC for high reliability
▪ Ultra-low power loss: 100 μΩ internal conductor resistance
▪ Galvanic isolation allows use in economical, high-side
current sensing in high voltage systems
▪ 3.0 to 5.5 V, single supply operation
▪ 120 kHz typical bandwidth
▪ 3 μs output rise time in response to step input current
▪ Output voltage proportional to AC or DC currents
▪ Factory-trimmed for accuracy
▪ Extremely stable output offset voltage
▪ Nearly zero magnetic hysteresis
The Allegro® ACS758 family of current sensor ICs provides
economical and precise solutions for AC or DC current sensing.
Typical applications include motor control, load detection and
management, power supply and DC-to-DC converter control,
inverter control, and overcurrent fault detection.
Package: 5-pin package
The output of the device has a positive slope (>VCC / 2) when an
increasing current flows through the primary copper conduction
path (from terminal 4 to terminal 5), which is the path used
for current sampling. The internal resistance of this conductive
path is 100 μΩ typical, providing low power loss.
The device consists of a precision, low-offset linear Hall
circuit with a copper conduction path located near the die.
Applied current flowing through this copper conduction path
generates a magnetic field which the Hall IC converts into a
proportional voltage. Device accuracy is optimized through the
close proximity of the magnetic signal to the Hall transducer.
A precise, proportional output voltage is provided by the
low-offset, chopper-stabilized BiCMOS Hall IC, which is
programmed for accuracy at the factory.
High level immunity to current conductor dV/dt and stray
electric fields, offered by Allegro proprietary integrated shield
technology, guarantees low output voltage ripple and low offset
drift in high-side, high voltage applications.
The thickness of the copper conductor allows survival of the
device at high overcurrent conditions. The terminals of the
PSS
Leadform
PFF
Leadform
Continued on the next page…
Additional leadforms available for qualifying volumes
Typical Application
+3.3 or 5 V
4
VCC
IP+
ACS758
IP
GND
5
1
CBYP
0.1 μF
2
CF
IP–
VIOUT
3
RF
VOUT
Application 1. The ACS758 outputs an analog signal, VOUT , that
varies linearly with the uni- or bi-directional AC or DC primary
sampled current, IP , within the range specified. CF is for optimal
noise management, with values that depend on the application.
ACS758-DS, Rev. 1
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Description (continued)
conductive path are electrically isolated from the signal leads (pins
1 through 3). This allows the ACS758 family of sensor ICs to be
used in applications requiring electrical isolation without the use of
opto-isolators or other costly isolation techniques.
The device is fully calibrated prior to shipment from the factory.
The ACS758 family is lead (Pb) free. All leads are plated with 100%
matte tin, and there is no Pb inside the package. The heavy gauge
leadframe is made of oxygen-free copper.
Selection Guide
Package
Terminals
Signal Pins
Primary Sampled
Current , IP
(A)
ACS758LCB-050B-PFF-T
Formed
Formed
±50
40
ACS758LCB-100B-PFF-T
Formed
Formed
±100
20
ACS758KCB-150B-PFF-T
Formed
Formed
ACS758KCB-150B-PSS-T
Straight
Straight
±150
13.3
–40 to 125
±200
10
–40 to 85
Part Number1
ACS758ECB-200B-PFF-T
Formed
Formed
ACS758ECB-200B-PSS-T
Straight
Straight
1Additional
Sensitivity
Sens (Typ.)
(mV/A)
TOP
(°C)
Packing2
–40 to 150
170 per bulk bag
leadform options available for qualified volumes
for additional packing options.
2Contact Allegro
Absolute Maximum Ratings
Characteristic
Symbol
Notes
Rating
Units
Forward Supply Voltage
VCC
8
V
Reverse Supply Voltage
VRCC
–0.5
V
353
VAC
Working Voltage for Reinforced Isolation
VWORKING
Voltage applied between pins 1-3 and 4-5;
tested at 3000 VAC for 1 minute according to
UL standard 60950-1
Forward Output Voltage
VIOUT
28
V
Reverse Output Voltage
VRIOUT
–0.5
V
Output Source Current
IOUT(Source)
VIOUT to GND
3
mA
IOUT(Sink)
VCC to VIOUT
1
mA
Output Sink Current
Nominal Operating Ambient Temperature
Maximum Junction
Storage Temperature
TOP
Range E
–40 to 85
ºC
Range K
–40 to 125
ºC
Range L
–40 to 150
ºC
TJ(max)
165
ºC
Tstg
–65 to 165
ºC
Rating
Units
TA = 25°C, 1s duration, 1% duty cycle
1200
A
TA = 85°C, 1s duration, 1% duty cycle
900
A
TA = 150°C, 1s duration, 1% duty cycle
600
A
Typical Overcurrent Capabilities1,2
Characteristic
Overcurrent
Symbol
IPOC
Notes
1Test
was done with Allegro evaluation board. The maximum allowed current is limited by TJ(max) only.
2For more overcurrent profiles, please see FAQ on the Allegro website, www.allegromicro.com.
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Functional Block Diagram
+3.3 to 5 V
VCC
IP+
Gain
Filter
Dynamic Offset
Cancellation
To all subcircuits
Amp
VIOUT
Out
0.1 μF
Gain
Temperature
Coefficient
Offset
Offset
Temperature
Coefficient
Trim Control
GND
IP–
Pin-out Diagram
IP+
IP–
4
3
VIOUT
2
GND
1
VCC
5
Terminal List Table
Number
Name
1
VCC
Device power supply terminal
Description
2
GND
Signal ground terminal
3
VIOUT
4
IP+
Terminal for current being sampled
5
IP–
Terminal for current being sampled
Analog output signal
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
COMMON OPERATING CHARACTERISTICS1 valid at TOP = –40°C to 150°C and VCC = 5 V, unless otherwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Supply Voltage
VCC
3
5.0
5.5
V
Supply Current
ICC
Output open
–
10
13.5
mA
Power-On Delay
tPOD
TA = 25°C
–
10
–
μs
–
3
–
μs
Rise Time2
Propagation Delay
tr
Time2
Response Time
tPROP
tRESPONSE
Internal Bandwidth3
BWi
IP step = 60% of IP+, 10% to 90% rise time, TA = 25°C,
COUT = 0.47 nF
TA = 25°C, COUT = 0.47 nF
–
1
–
μs
Measured as sum of tPROP and tr
–
4
–
μs
–3 dB; TA = 25°C, COUT = 0.47 nF
–
120
–
kHz
Output Load Resistance
RLOAD(MIN)
VIOUT to GND
4.7
–
–
kΩ
Output Load Capacitance
CLOAD(MAX)
VIOUT to GND
–
–
10
nF
Primary Conductor Resistance
Symmetry2
Quiescent Output
Ratiometry2
RPRIMARY
ESYM
Voltage4
VIOUT(Q)
VRAT
TA = 25°C
–
100
–
μΩ
Over half-scale of Ip
99
100
101
%
IP = 0 A, TA = 25°C
VCC = 4.5 to 5.5 V
–
–
VCC/2
100
–
–
V
%
1Device
is factory-trimmed at 5 V, for optimal accuracy.
Characteristic Definitions section of this datasheet.
3Calculated using the formula BW = 0.35 / t .
i
r
4V
IOUT(Q) may drift over the lifetime of the device by as much as ±25 mV.
2See
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
X050 PERFORMANCE CHARACTERISTICS1:
Characteristic
Primary Sampled Current
Noise2
Min.
Typ.
Max.
–50
–
50
A
–
40
–
mV/A
Sens(TOP)HT Full scale of IP applied for 5 ms, TOP = 25°C to 150°C
–
39.4
–
mV/A
Sens(TOP)LT Full scale of IP applied for 5 ms,TOP = –40°C to 25°C
–
41
–
mV/A
mV
VNOISE
Nonlinearity
Magnetic Offset Error
Total Output Error4
Full scale of IP applied for 5 ms, TA = 25°C
TA= 25°C, 10 nF on VIOUT pin to GND
Units
–
10
–
–1
–
1
%
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TOP = 25°C to 150°C
–
±15
–
mV
VOE(TOP)LT IP = 0 A, TOP = –40°C to 25°C
–
±35
–
mV
ELIN
VOE(TA)
Electrical Offset Voltage3
Test Conditions
IP
SensTA
Sensitivity
TOP = –40°C to 150°C, VCC = 5 V, unless otherwise specified
Symbol
Up to full scale of IP , IP applied for 5 ms
IP = 0 A, TA = 25°C
IERROM
IP = 0 A, TA = 25°C, after excursion of 50 A
–
100
–
mA
ETOT(HT)
Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 150°C
–
–1.2
–
%
ETOT(LT)
Over full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C
–
2
–
%
Typ.
Max.
Units
–100
–
100
A
–
20
–
mV/A
Sens(TOP)HT Full scale of IP applied for 5 ms, TOP = 25°C to 150°C
–
19.75
–
mV/A
Sens(TOP)LT Full scale of IP applied for 5 ms, TOP = –40°C to 25°C
–
20.5
–
mV/A
–
6
–
mV
– 1.25
–
1.25
%
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TOP = 25°C to 150°C
–
±20
–
mV
VOE(TOP)LT IP = 0 A, TOP = –40°C to 25°C
–
±20
–
mV
1See
Characteristic Performance Data page for parameter distributions over temperature range.
2±3 sigma noise voltage.
3V
OE(TOP) drift is referred to ideal VIOUT(Q) = 2.5 V.
4Percentage of I . Output filtered.
P
X100 PERFORMANCE CHARACTERISTICS1:
Characteristic
Primary Sampled Current
Noise2
Nonlinearity
VNOISE
ELIN
VOE(TA)
Electrical Offset Voltage3
Magnetic Offset Error
Total Output Error4
Test Conditions
IP
SensTA
Sensitivity
TOP = –40°C to 150°C, VCC = 5 V, unless otherwise specified
Symbol
Full scale of IP applied for 5 ms, TA = 25°C
TA= 25°C, 10 nF on VIOUT pin to GND
Up to full scale of IP , IP applied for 5 ms
IP = 0 A, TA = 25°C
Min.
IERROM
IP = 0 A, TA = 25°C, after excursion of 100 A
–
150
–
mA
ETOT(HT)
Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 150°C
–
–1.3
–
%
ETOT(LT)
Over full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C
–
2.4
–
%
1See
Characteristic Performance Data page for parameter distributions over temperature range.
2±3 sigma noise voltage.
3V
OE(TOP) drift is referred to ideal VIOUT(Q) = 2.5 V.
4Percentage of I . Output filtered.
P
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
X150 PERFORMANCE CHARACTERISTICS1:
Characteristic
Primary Sampled Current
Noise2
Magnetic Offset Error
Total Output Error4
Typ.
Max.
–
150
Units
A
–
13.3
–
mV/A
–
13.1
–
mV/A
Sens(TOP)LT Full scale of IP applied for 5 ms, TOP = –40°C to 25°C
–
13.5
–
mV/A
mV
–
4
–
–1
–
1
%
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TOP = 25°C to 125°C
–
±14
–
mV
VOE(TOP)LT IP = 0 A, TOP = –40°C to 25°C
–
±24
–
mV
ELIN
VOE(TA)
Electrical Offset Voltage3
Full scale of IP applied for 5 ms, TA = 25°C
Min.
–150
Sens(TOP)HT Full scale of IP applied for 5 ms, TOP = 25°C to 125°C
VNOISE
Nonlinearity
Test Conditions
IP
SensTA
Sensitivity
TOP = –40°C to 125°C, VCC = 5 V, unless otherwise specified
Symbol
TA= 25°C, 10 nF on VIOUT pin to GND
Up to full scale of IP , IP applied for 5 ms
IP = 0 A, TA = 25°C
IERROM
IP = 0 A, TA = 25°C, after excursion of 150 A
–
205
–
mA
ETOT(HT)
Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 125°C
–
–1.8
–
%
ETOT(LT)
Over full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C
–
1.6
–
%
Typ.
Max.
Units
–200
–
200
A
–
10
–
mV/A
1See
Characteristic Performance Data page for parameter distributions over temperature range.
2±3 sigma noise voltage.
3V
OE(TOP) drift is referred to ideal VIOUT(Q) = 2.5 V.
4Percentage of I . Output filtered.
P
X200 PERFORMANCE CHARACTERISTICS1:
Characteristic
Primary Sampled Current
Noise2
Nonlinearity
Magnetic Offset Error
Total Output Error4
Full scale of IP applied for 5 ms, TA = 25°C
Min.
Sens(TOP)HT Full scale of IP applied for 5 ms, TOP = 25°C to 85°C
–
9.88
–
mV/A
Sens(TOP)LT Full scale of IP applied for 5 ms, TOP = –40°C to 25°C
–
10.13
–
mV/A
mV
VNOISE
ELIN
VOE(TA)
Electrical Offset Voltage3
Test Conditions
IP
SensTA
Sensitivity
TOP = –40°C to 85°C, VCC = 5 V, unless otherwise specified
Symbol
TA= 25°C, 10 nF on VIOUT pin to GND
Up to full scale of IP , IP applied for 5 ms
IP = 0 A, TA = 25°C
–
3
–
–1
–
1
%
–
±5
–
mV
VOE(TOP)HT IP = 0 A, TOP = 25°C to 85°C
–
±15
–
mV
VOE(TOP)LT IP = 0 A, TOP = –40°C to 25°C
–
±25
–
mV
IERROM
IP = 0 A, TA = 25°C, after excursion of 200 A
–
230
–
mA
ETOT(HT)
Over full scale of IP , IP applied for 5 ms, TOP = 25°C to 85°C
–
–1.2
–
%
ETOT(LT)
Over full scale of IP , IP applied for 5 ms, TOP = –40°C to 25°C
–
1.2
–
%
1See
Characteristic Performance Data page for parameter distributions over temperature range.
2±3 sigma noise voltage.
3V
OE(TOP) drift is referred to ideal VIOUT(Q) = 2.5 V .
4Percentage of I . Output filtered.
P
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Characteristic Performance Data
Data taken using the ACS758LCB-50B
Accuracy Data
Electrical Offset Voltage versus Ambient Temperature
30
42.0
20
42.5
Sens (mV/A)
10
VOE (mV)
Sensitivity versus Ambient Temperature
0
-10
-20
41.0
40.5
40.0
39.5
-30
39.0
-40
-50
–50
-25
0
25
50
75
100
125
38.5
–50
150
-25
0
25
TA (°C)
0.40
100.35
0.35
100.30
0.30
100.25
0.25
0.20
100.10
100.05
0.05
100.00
25
50
75
100
125
99.95
–50
150
-25
0
25
TA (°C)
Magnetic Offset Error versus Ambient Temperature
50
75
100
125
150
Total Output Error versus Ambient Temperature
6
5
120
4
100
3
80
2
ETOT (%)
IERROM (mA)
150
TA (°C)
140
60
40
1
0
-1
-2
20
0
–50
125
100.15
0.10
0
100
100.20
0.15
-25
75
Symmetry versus Ambient Temperature
100.40
ESYM (%)
ELIN (%)
Nonlinearity versus Ambient Temperature
0.45
0
–50
50
TA (°C)
-3
-25
0
25
50
75
100
125
-4
–50
150
-25
0
25
50
75
100
125
150
TA (°C)
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Characteristic Performance Data
Data taken using the ACS758LCB-100B
Accuracy Data
Electrical Offset Voltage versus Ambient Temperature
21.2
20
21.0
15
20.8
Sens (mV/A)
25
10
VOE (mV)
Sensitivity versus Ambient Temperature
5
0
-5
20.6
20.4
20.2
20.0
-10
19.8
-15
19.6
-20
19.4
-25
–50
-25
0
25
50
75
100
125
19.2
–50
150
-25
0
25
TA (°C)
100
125
150
Symmetry versus Ambient Temperature
0.40
100.6
0.35
100.5
0.30
100.4
ESYM (%)
ELIN (%)
75
TA (°C)
Nonlinearity versus Ambient Temperature
0.25
0.20
0.15
100.3
100.2
100.1
100.0
0.10
99.9
0.05
99.8
0
–50
-25
0
25
50
75
100
125
99.7
–50
150
-25
0
25
TA (°C)
Magnetic Offset Error versus Ambient Temperature
180
170
ETOT (%)
160
150
130
120
110
-25
0
25
50
75
100
125
150
Total Output Error versus Ambient Temperature
190
100
–50
50
TA (°C)
200
IERROM (mA)
50
75
100
125
150
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
–50
-25
0
25
50
75
100
125
150
TA (°C)
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Characteristic Performance Data
Data taken using the ACS758KCB-150B
Accuracy Data
Electrical Offset Voltage versus Ambient Temperature
Sensitivity versus Ambient Temperature
20
14.0
15
13.8
Sens (mV/A)
10
VOE (mV)
5
0
-5
-10
-15
13.6
13.4
13.2
13.0
-20
12.8
-25
-30
–60
–40
–20
0
20
40
60
80
100
120
12.6
–60
140
–40
–20
0
20
TA (°C)
Nonlinearity versus Ambient Temperature
80
100
120
140
Symmetry versus Ambient Temperature
100.6
0.25
100.5
02.0
ESYM (%)
ELIN (%)
60
100.7
0.30
0.15
100.4
100.3
100.2
100.1
0.10
100.0
0.05
99.9
0
–60
–40
–20
0
20
40
60
80
100
120
99.8
–60
140
–40
–20
0
20
TA (°C)
Magnetic Offset Error versus Ambient Temperature
ETOT (%)
200
150
100
50
0
–40
–20
0
20
40
60
80
100
120
140
Total Output Error versus Ambient Temperature
250
–60
40
TA (°C)
300
IERROM (mA)
40
TA (°C)
60
80
100
120
140
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
–60
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Characteristic Performance Data
Data taken using the ACS758ECB-200B
Accuracy Data
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
–60
Sensitivity versus Ambient Temperature
10.4
10.3
Sens (mV/A)
VOE (mV)
Electrical Offset Voltage versus Ambient Temperature
10.2
10.1
10.0
9.9
9.8
9.7
9.6
–40
–20
0
20
40
60
80
100
120
9.5
–60
140
–40
–20
0
20
TA (°C)
100
120
140
100.6
100.4
100.2
100.0
99.8
99.6
–40
–20
0
20
40
60
80
100
120
140
–60
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
Magnetic Offset Error versus Ambient Temperature
Total Output Error versus Ambient Temperature
4
350
3
300
2
250
1
200
ETOT (%)
IERROM (mA)
80
Symmetry versus Ambient Temperature
TA (°C)
150
100
0
-1
-2
-3
-4
50
0
–60
60
100.8
ESYM (%)
ELIN (%)
Nonlinearity versus Ambient Temperature
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0
-0.02
-0.04
-0.06
–60
40
TA (°C)
-5
–40
–20
0
20
40
60
80
100
120
-6
–60
140
–40
–20
0
20
40
60
80
100
120
140
TA (°C)
TA (°C)
Typical Maximum Limit
Mean
Typical Minimum Limit
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Characteristic Performance Data
Data taken using the ACS758LCB-100
Timing Data
Rise Time
Propagation Delay Time
IP (20 A/div.)
IP (20 A/div.)
VIOUT (0.5 V/div.)
VIOUT (0.5 V/div.)
997 ns
2.988 μs
t (2 μs/div.)
t (2 μs/div.)
Response Time
Power-on Delay
VCC
IP (20 A/div.)
VIOUT (0.5 V/div.)
9.034 μs
VIOUT (1 V/div.)
(IP = 60 A DC)
3.960 μs
t (2 μs/div.)
t (2 μs/div.)
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
11
ACS758xCB
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
Characteristic Definitions
Definitions of Accuracy Characteristics
Sensitivity (Sens). The change in device 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
half-scale current of the device.
Noise (VNOISE). 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.
Nonlinearity (ELIN). The degree to which the voltage output
from the IC varies in direct proportion to the primary current
through its half-scale amplitude. Nonlinearity in the output can be
attributed to the saturation of the flux concentrator approaching
the half-scale current. The following equation is used to derive
the linearity:
{ [
100 1–
Δ gain × % sat ( VIOUT_half-scale amperes –VIOUT(Q) )
2 (VIOUT_quarter-scale amperes – VIOUT(Q) )
[{
where
∆ gain = the gain variation as a function of temperature
changes from 25ºC,
% sat = the percentage of saturation of the flux concentrator, which becomes significant as the current being sampled
approaches half-scale ±IP , and
VIOUT_half-scale amperes = the output voltage (V) when the
sampled current approximates half-scale ±IP .
Symmetry (ESYM). The degree to which the absolute voltage
output from the IC varies in proportion to either a positive or
negative half-scale primary current. The following equation is
used to derive symmetry:
100
VIOUT_+ half-scale amperes – VIOUT(Q)
VIOUT(Q) – VIOUT_–half-scale amperes
Ratiometry. The device features a ratiometric output. This
means that the quiescent voltage output, VIOUTQ, and the magnetic sensitivity, Sens, are proportional to the supply voltage, VCC.
The ratiometric change (%) in the quiescent voltage output is
defined as:
$VIOUTQ($V) =
VIOUTQ(VCC) VIOUTQ(5V)
VCC
5V
s%
and the ratiometric change (%) in sensitivity is defined as:
$Sens($V =
Sens(VCC
VCC
Sens(V
5V
s%
Quiescent output voltage (VIOUT(Q)). The output of the device
when the primary current is zero. For a unipolar supply voltage,
it nominally remains at VCC ⁄ 2. Thus, VCC = 5 V translates into
VIOUT(Q) = 2.5 V. Variation in VIOUT(Q) can be attributed to the
resolution of the Allegro linear IC quiescent voltage trim, magnetic hysteresis, and thermal drift.
Electrical offset voltage (VOE). The deviation of the device output from its ideal quiescent value of VCC ⁄ 2 due to nonmagnetic
causes.
Magnetic offset error (IERROM). The magnetic offset is due to
the residual magnetism (remnant field) of the core material. The
magnetic offset error is highest when the magnetic circuit has
been saturated, usually when the device has been subjected to a
full-scale or high-current overload condition. The magnetic offset
is largely dependent on the material used as a flux concentrator.
The larger magnetic offsets are observed at the lower operating
temperatures.
Total Output Error (ETOT). The maximum deviation of the
actual output from its ideal value, also referred to as accuracy,
illustrated graphically in the output voltage versus current chart
on the following page.
ETOT is divided into four areas:
0 A at 25°C. Accuracy at the zero current flow at 25°C, without the effects of temperature.
0 A over Δ temperature. Accuracy at the zero current flow
including temperature effects.
Half-scale current at 25°C. Accuracy at the the half-scale current
at 25°C, without the effects of temperature.
Half-scale current over Δ temperature. Accuracy at the halfscale current flow including temperature effects.
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
ACS758xCB
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
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 device
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 device, 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
Output Voltage versus Sampled Current
Total Output Error at 0 A and at Half-Scale Current
Transducer Output
10
0
Rise Time, tr
t
Increasing VIOUT(V)
Accuracy
Over $Temp erature
Accuracy
25°C Only
Propagation delay (tPROP). The time required for the device
output to reflect a change in the primary current signal. Propagation delay is attributed to inductive loading within the linear IC
package, as well as in the inductive loop formed by the primary
conductor geometry. Propagation delay can be considered as a
fixed time offset and may be compensated.
Average
VIOUT
Accuracy
Over $Temp erature
Accuracy
25°C Only
IP(min)
–IP (A)
+IP (A)
Half Scale
I (%)
IP(max)
Primary Current
0A
90
Transducer Output
0
Propagation Time, tPROP
t
Accuracy
25°C Only
Accuracy
Over $Temp erature
Decreasing VIOUT(V)
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Chopper Stabilization Technique
Chopper Stabilization is an innovative circuit technique that is
used to minimize the offset voltage of a Hall element and an associated on-chip amplifier. Allegro patented a Chopper Stabilization technique that nearly eliminates Hall IC output drift induced
by temperature or package stress effects.
This offset reduction technique is based on a signal modulationdemodulation process. Modulation is used to separate the undesired DC offset signal from the magnetically induced signal in the
frequency domain. Then, using a low-pass filter, the modulated
DC offset is suppressed while the magnetically induced signal
passes through the filter. The anti-aliasing filter prevents aliasing
from happening in applications with high frequency signal com-
ponents which are beyond the user’s frequency range of interest.
As a result of this chopper stabilization approach, the output
voltage from the Hall IC is desensitized to the effects of temperature and mechanical stress. This technique produces devices that
have an extremely stable Electrical Offset Voltage, are immune to
thermal stress, and have precise recoverability after temperature
cycling.
This technique is made possible through the use of a BiCMOS
process that allows the use of low-offset and low-noise amplifiers
in combination with high-density logic integration and sample
and hold circuits.
Regulator
Clock/Logic
Sample and
Hold
Amp
Anti-aliasing
Filter
Hall Element
Low-Pass
Filter
Concept of Chopper Stabilization Technique
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Package CB, 5-pin package, leadform PFF
0.5
R1
R3
0.5 B
14.0±0.2
3.0±0.2
1.50±0.10
4.0±0.2
5
4
4
R2
21.4
3
1º±2°
A
3.5±0.2
0.8
17.5±0.2
1.5
13.00±0.10
1.91
B
Branded
Face
4.40±0.10
PCB Layout Reference View
2.9±0.2
NNNNNNN
TTT - AAA
5º±5°
1
2
+0.060
0.381 –0.030
3
10.00±0.10
3.5±0.2
LLLLLLL
YYWW
1
7.00±0.10
C Standard Branding Reference View
0.51±0.10
1.9±0.2
N = Device part number
T = Temperature code
A = Amperage range
L = Lot number
Y = Last two digits of year of manufacture
W = Week of manufacture
= Supplier emblem
For Reference Only; not for tooling use (reference DWG-9111, DWG-9110)
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 Dambar removal intrusion
B Perimeter through-holes recommended
C Branding scale and appearance at supplier discretion
Creepage distance, current terminals to signal pins: 7.25 mm
Clearance distance, current terminals to signal pins: 7.25 mm
Package mass: 4.63 g typical
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
15
Thermally Enhanced, Fully Integrated, Hall Effect-Based
Linear Current Sensor IC with 100 μΩ Current Conductor
ACS758xCB
Package CB, 5-pin package, leadform PSS
14.0±0.2
3.0±0.2
4.0±0.2
5
4
1.50±0.10
A
NNNNNNN
TTT - AAA
2.75±0.10
23.50±0.5
LLLLLLL
13.00±0.10
YYWW
4.40±0.10
1
Branded
Face
3.18±0.10
11.0±0.05
B Standard Branding Reference View
N = Device part number
T = Temperature code
A = Amperage range
L = Lot number
Y = Last two digits of year of manufacture
W = Week of manufacture
= Supplier emblem
+0.060
0.381 –0.030
1
2
3
10.00±0.10
For Reference Only; not for tooling use (reference DWG-9111, DWG-9110)
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
7.00±0.10
A Dambar removal intrusion
B Branding scale and appearance at supplier discretion
0.51±0.10
1.9±0.2
Creepage distance, current terminals to signal pins: 7.25 mm
Clearance distance, current terminals to signal pins: 7.25 mm
Package mass: 4.63 g typical
Copyright ©2008-2009, Allegro MicroSystems, Inc.
The products described herein are manufactured under one or more of the following U.S. patents: 5,619,137; 5,621,319; 6,781,359; 7,075,287;
7,166,807; 7,265,531; 7,425,821; or other patents pending.
Allegro MicroSystems, Inc. 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, Inc. 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, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
16