ALLEGRO ACS750LCA-075

Current Sensor: ACS750xCA-075
5
The Allegro ACS750 family of current sensors provides
economical and precise solutions for current sensing in industrial,
commercial, automotive, and communications systems. The device
package allows for easy implementation by the customer. Typical
applications include motor control, load detection and management,
switched mode power supplies and over-current fault protection.
4
123
Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Vcc
Gnd
Output
Ip+
Ip-
ABSOLUTE MAXIMUM RATINGS
Operating Temperature
‘S’……….……………….. -20 to +85°C
‘L’………………………. -40 to +150°C
Supply Voltage, Vcc
16V
Output Voltage
16V
Output Current Source
3mA
Output Current Sink
10mA
Maximum Storage Temperature
170°C
Maximum Junction Temperature
165°C
Thermal Resistance, RΘJA
TBD °C/W
Always order by complete part number:
ACS750SCA-075 or
ACS750LCA-075
31Oct03, CMG, Rev 2.0
The sensor consists of a precision linear Hall IC optimized to an
internal magnetic circuit to increase device sensitivity.
The
combination of a precisely controlled self-aligning assembly process
(patents pending) and the factory programmed precision of the
linear Hall sensor result in high level performance and product
uniformity.
The primary conductor used for current sensing (terminals 4 and 5)
is designed for extremely low power loss. The power terminals are
also electrically isolated from the sensor leads (pins 1 – 3). This
allows the ACS750 family of sensors to be used in applications
requiring electrical isolation without the use of opto-isolators or other
costly isolation techniques.
The output of the device has a positive slope (>Vcc/2) when an
increasing current flows from terminal 4 to terminal 5.
Features and Benefits
•
Monolithic Hall IC for High Reliability
•
Single +5V Supply
•
High Isolation Voltage
•
Lead-free
•
Automotive Temperature Range
•
End-of-line Factory Trimmed for Gain and Offset
•
Ultra-low Power Loss: Low Resistance of Primary Conductor
•
Ratiometric Output from Supply Voltage
•
Low Thermal Drift of Offset Voltage
•
On-chip Transient Protection
•
Small Package Size with Easy Mounting Capability
Applications
• Automotive Systems
• Industrial Systems
• Motor Control
• Servo Systems
• Power Conversion
• Battery Monitors
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
1
Current Sensor: ACS750xCA-075
Characteristic
Symbol
Test Conditions
Limits
ELECTRICAL CHARACTERISTICS, over temperature unless otherwise stated
Min.
Typ.
Max.
Primary Sensed Current
IP
-75
75
Supply Voltage
VCC
4.5
5.0
5.5
Supply Current
ICC
Vcc = 5.0V, output open
7
10
Output Resistance
ROUT
Iout = 1.2 mA
1
2
Primary Conductor
RPRIMARY
130
IP = ±100A; +25°C
Resistance
Pins 1-3 and 4-5,
Isolation Voltage
VISO
2.5
60 Hz, 1 minute
PERFORMANCE CHARACTERISTICS, -20 °C to +85 °C, Vcc = 5V unless otherwise specified
Propagation time
tPROP
4
IP = ±50A (±75A TBD)
Response time
tRESPONSE
27
IP = ±50A (±75A TBD)
Rise time
tr
26
IP = ±50A (±75A TBD)
Frequency Bandwidth
f
-3dB
13
18.75
19.75
20.75
±IP, T = +25°C
Sensitivity
Sens
17.5
21.5
±IP, Over Temperature
Peak-to-Peak; T = +25°C
Noise
VNOISE
7
External Filter BW = 24kHz
Non-linearity
EL
+/- 5
±IP
Symmetry
ES
97
100
103
±IP
I = 0A, T = +25°C
-40
Vcc/2
+40
Electrical Offset Voltage
VOE
(Magnetic error not included)
I = 0A, Over Temperature
-50
Vcc/2
+50
Magnetic Offset Error
VOM
I = 0A, after excursion of 100A
+/- 0.3
+/- 0.8
+/1
±I
,
T
=
+25°C
Total Accuracy
P
XIp
(Including all offsets)
+/- 13
±IP, Over Temperature
PERFORMANCE CHARACTERISTICS, -40 °C to +150 °C, Vcc = 5V unless otherwise specified
Propagation time
tPROP
4
IP = ±50A (±75A TBD)
Response time
tRESPONSE
27
IP = ±50A (±75A TBD)
Rise time
tr
26
IP = ±50A (±75A TBD)
Frequency Bandwidth
f
-3dB
13
18.75
19.75
20.75
±IP, T = +25°C
Sensitivity
Sens
16.5
23
±IP, Over Temperature
Peak to Peak; T = +25°C
7
Noise
VNOISE
External Filter BW = 40kHz
Non-linearity
EL
+/- 5
±IP
Symmetry
ES
97
100
103
±IP
I = 0A, T = +25°C
-40
Vcc/2
+40
Electrical Offset Voltage
VOE
(Magnetic error not included)
I = 0A, Over Temperature
-60
Vcc/2
+60
Magnetic Offset Error
VOM
I = 0A, after excursion of 100A
+/- 0.3
+/- 0.8
+/1
±I
,
T
=
+25°C
Total Accuracy
P
XIp
(Including all offsets)
+/- 15
±IP, Over Temperature
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
Units
A
V
mA
Ω
µΩ
kV
µs
kHz
mV/A
mV/A
mV
%
%
mV
mV
A
%
µs
kHz
mV/A
mV/A
mV
%
%
mV
mV
A
%
2
Current Sensor: ACS750xCA-075
Functional Block Diagram
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
3
Current Sensor: ACS750xCA-075
Typical Performance Characteristics
Supply Current
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
8
Sensitivity
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
25
7.8
7.6
20
Sensitivity [mV/A]
Icc [mA]
7.4
7.2
7
6.8
6.6
6.4
15
-40C
-20C
25C
85C
150C
10
5
6.2
6
0
-50
-25
0
25
50
75
100
125
150
-100
-75
-50
-25
Temperature [°C]
Vout vs Primary Current
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
75
100
100.4
4
100.3
3.5
100.2
3
100.1
2.5
100
-40C
-20C
25C
85C
150C
2
1.5
1
99.9
99.8
99.7
99.6
99.5
-50
0.5
-100
-75
-50
-25
0
25
Primary Current (A)
50
75
100
Linearity
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
5
5
4.5
4.5
Linearity @ +75 Amp s [%]
4
3.5
Ip = -75A
3
Ip = 75A
Symmetry
[%]
Vout (V)
50
Symmetr
Vcc =
200 units
5V/ 2 CS lots / 1
IC l t
100.5
4.5
Linearity @ -75 Amps [%]
25
Primary Current (A)
2.5
2
1.5
1
0.5
-25
0
25
50
75
Temperature
[°C]
100
125
150
125
150
Linearity
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
4
Ip = +75A
3.5
3
2.5
2
1.5
1
0.5
0
0
-50
-25
0
25
50
75
Temperature [°C]
31Oct03, CMG, Rev 2.0
100
125
150
-50
-25
0
25
50
75
Temperature [°C]
100
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
4
Current Sensor: ACS750xCA-075
Typical Performance Characteristics (continued)
Magnetic Offset
Vcc = 5V
200 units / 2 CS lots / 1 IC lot
1
Magnetic Offset [A]
0.8
0.6
0.4
0.2
0
I = 0 A, after excursion to 100 A
-0.2
-0.4
-0.6
-0.8
-1
-50
-25
0
25
50
75
Temperature [°C]
100
125
150
0 Amp Accuracy
Vcc = 5V
Without Offset
200 units / 2 CS lots / 1 IC lot
1
0 Amp Accuracy [A]
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1
-50
31Oct03, CMG, Rev 2.0
-25
0
25
50
75
Temperature [°C]
100
125
150
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
5
Current Sensor: ACS750xCA-075
Definitions of Accuracy Characteristics
Sensitivity: The sensitivity is the change in sensor output to 1A 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 trimmed at the factory to optimize the sensitivity (mV/A) for the full-scale current of
the device.
Noise: The noise is the product of the linear IC amplifier gain (mV/G) and the noise floor for the Allegro Hall
effect linear IC (~1Gauss). 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: The linearity is the degree to which the voltage output from the sensor varies in direct proportion
to the primary current through its full-scale amplitude. Linearity reveals the maximum deviation from the ideal
transfer curve for this transducer. Non-linearity in the output can be attributed to the gain variation across
temperature and saturation of the flux concentrator approaching the full scale current. The following equation
is used to derive the linearity:
[1-[(Vout_full-scale Amps –Vout_0A)/(2*(Vout_1/2 full-scale Amps –Vout_0A))]]*100
Symmetry: Symmetry is 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 equation is used to derive symmetry:
[(Vout_full-scale Amps –Vout_0A)/(Vout_0A – Vout_-full-scale Amps)]*100
Electrical offset voltage: The quiescent output voltage (VOE) is the output of the sensor when the primary
current is zero. For a unipolar supply voltage, VOE nominally sits at Vcc/2. Vcc = 5V translates into VOE =
2.5V. Variation in VOE can be attributed to the resolution of the Allegro linear IC quiescent voltage trim,
magnetic hysteresis, and thermal drift.
Magnetic offset error: 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 largest magnetic offset is observed at the lowest
operating temperature.
Accuracy: The accuracy represents the maximum deviation of the actual output from its ideal value. This is
also known as the total error. The accuracy is illustrated graphically in Figure #1. The accuracy is divided into
four areas as defined below:
•
•
•
•
0 A @ 25°C: Accuracy of sensing zero current flow at 25°C, without the effects of temperature.
0 A over temperature: Accuracy of sensing zero current flow including temperature effects.
Full-scale current @ 25°C: Accuracy of sensing the full-scale current at 25°C, without the effects of temperature.
Full-scale current over temperature: Accuracy of sensing full-scale current flow including temperature effects.
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
6
Current Sensor: ACS750xCA-075
Figure 1: Output Voltage vs. Current, illustrating sensor accuracy at 0A and full-scale current
VOUT (Volts)
Average
Output
Accuracy
Full Scale
25°C Only
Accuracy
Full Scale
Over Temp
Accuracy
0Amp
25°C Only
Accuracy
0Amp
Over Temp
IP (Amps)
+/-75A Full Scale
Accuracy
Full Scale
25°C Only
Accuracy
Full Scale
Over Temp
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
7
Current Sensor: ACS750xCA-075
Definitions of Dynamic Response Characteristics
Propagation delay: Propagation delay is the time that it takes for the sensor 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 the inductive loop formed by the primacy conductor geometry. Propagation delay can be considered as a
fixed time offset and may be compensated.
Response time: Response time is the time between when the primary current signal reaches 90% of its final
value and when the sensor reaches 90% of its output corresponding to the applied current.
Rise time: Rise time is the time between the sensor’s output reaching 10 and 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(-3dB) = 0.35/tr.
Both rise time and response time are detrimentally affected by eddy current losses observed in the conductive
IC ground plane and, to varying degrees, in the ferrous flux concentrator within the current sensor package.
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
8
Current Sensor: ACS750xCA-075
Peak to Peak Noise, applying low-pass filter to ACS750 output
Low Pass Filter Break Frequency
Unfiltered
1.4MHz
400kHz
160kHz
80kHz
24kHz
Typical Peak to Peak Noise
22.7 mV
21 mV
TBD
TBD
TBD
7.1 mV
Step Resonsponse, IPRIMARY = 0 to 50A
ACS750 Output
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
9
Current Sensor: ACS750xCA-075
PACKAGE DRAWING
Notes:
1.
2.
3.
4.
This drawing is only a preliminary issue and no tolerances are implied to any dimensions.
Draft angle is 10° unless otherwise specified.
There is no plating in areas that are trimmed.
SIP lead flash along the edge or sides for 3mm from the package due to resin bleeding.
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
10
Current Sensor: ACS750xCA-075
The products described herein are manufactured under one or
more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283;
5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719;
5,686,894; 5,694,038; 5,729,130; 5,917,320; and 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 products are not authorized for use as critical components
in life-support appliances, devices, or systems without express written approval.
The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsibility
for its use; nor for any infringements of patents or other rights of
third parties that may result from its use.
31Oct03, CMG, Rev 2.0
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2003, Allegro MicroSystems, Inc.
11