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ACS722

Approximate Scale 1:1

The Allegro

™

ACS722 current sensor IC is an economical and

precise solution for AC or DC current sensing in industrial,

commercial, and communications 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.

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 and 2, to pins 3

and 4), which is the path used for current sensing. The internal

resistance of this conductive path is 0.65 mΩ typical, providing

low power loss.

The terminals of the conductive path are electrically isolated

from the sensor leads (pins 5 through 8). This allows the

ACS722 current sensor IC to be used in high-side current sense

applications without the use of high-side differential amplifiers

or other costly isolation techniques.

The ACS722 is provided in a small, low profile surface mount

SOIC8 package. The leadframe is plated with 100% matte tin,

ACS722-DS, Rev. 2

• 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 = 2.4 kVrms

□ Basic Isolation Working Voltage = 420 Vpk/297

Vrms

• Industry-leading noise performance with greatly

improved bandwidth through proprietary amplifier and

filter design techniques

• Pin-selectable band width: 80 kHz for high bandwidth

applications or 20 kHz for low noise performance

• 0.65 mΩ primary conductor resistance for low power

loss and high inrush current withstand capability

• Small footprint, low-profile SOIC8 package suitable for

space-constrained applications

• Integrated shield virtually eliminates capacitive coupling

from current conductor to die, greatly suppressing output

noise due to high dv/dt transients

• 3 to 3.6 V, single supply operation

High Accuracy, Galvanically Isolated Current Sensor IC

With Small Footprint SOIC8 Package

Continued on the next page…

Package: 8-pin SOIC (suff ix LC)

Typical Application

BYPASS

0.1 µF

ACS722

IP+ VCC

–I

IP+ VIOUT

IP–

BW_SEL

GND

The ACS722 outputs an analog

signal, V

IOUT

, that changes,

proportionally, with the

bidirectional AC or DC primary

sensed current, I

, within

the specified measurement

range. The BW_SEL pin can

be used to select one of the

two bandwidths to optimize the

noise performance. Grounding

the BW_SEL pin puts the part

in the high bandwidth (80 kHz)

mode.

Continued on the next page…

CB Certif icate Number:

US-22334-A1-UL

FEATURES AND BENEFITS DESCRIPTION

Summary of content (22 pages)

PAGE 1
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package FEATURES AND BENEFITS DESCRIPTION • 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 = 2.
PAGE 2
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package Features and Benefits (continued) Description (continued) • Output voltage proportional to AC or DC current • 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 which is compatible with standard lead (Pb) free printed circuit boar
PAGE 3
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package SPECIFICATIONS Absolute Maximum Ratings Characteristic Supply Voltage Symbol Rating Units VCC Notes 6 V Reverse Supply Voltage VRCC –0.1 V Output Voltage VIOUT 25 V Reverse Output Voltage VRIOUT Operating Ambient Temperature TA Range L –0.
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High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 VCC Master Current Supply To All Subcircuits Programming Control POR Hall Current Drive Temperature Sensor EEPROM and Control Logic Offset Control IP+ Sensitivity Control IP– Dynamic Offset Cancellation IP+ Tuned Filter VIOUT IP– BW_SEL GND Functional Block Diagram Allegro MicroSystems, LLC 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.
PAGE 5
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package Pin-out Diagram and Terminal List IP+ 1 8 VCC IP+ 2 7 VIOUT IP– 3 6 BW_SEL IP– 4 5 GND Pin-out Diagram Terminal List Table Number Name 1, 2 IP+ 3, 4 IP– 5 GND 6 BW_SEL 7 VIOUT 8 VCC Description Terminals for current being sensed; fused internally Terminals for current being sensed; fused internally Signal ground terminal Terminal for selecting 20 kHz or 80 kHz bandwidth Analog o
PAGE 6
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package COMMON ELECTRICAL CHARACTERISTICS1: valid through the full range of TA = –40°C to 150°C , and at VCC = 3.3 V; unless otherwise specif ied Characteristic Symbol Min. Typ. Max. Units 3 3.3 3.6 V VCC within VCC(min) and VCC(max) – 9 12 mA VIOUT to GND – – 10 nF 4.7 – – kΩ – 0.
PAGE 7
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package xLLCTR-5AB PERFORMANCE CHARACTERISTICS: TA Range L, valid at TA = – 40°C to 150°C, VCC = 3.3 V, unless oth- erwise specif ied Characteristic Symbol Test Conditions Min. Typ. Max. Units Nominal Performance Current Sensing Range Sensitivity Zero Current Output Voltage IPR Sens VIOUT(Q) –5 – 5 A IPR(min) < IP < IPR(max) – 264 – mV/A Bidirectional; IP = 0 A – VCC x 0.
PAGE 8
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package xLLCTR-10AU PERFORMANCE CHARACTERISTICS: TA Range L, valid at TA = – 40°C to 150°C, VCC = 3.3 V, unless otherwise specif ied Characteristic Symbol Test Conditions Min. Typ. Max. Units Nominal Performance Current Sensing Range Sensitivity Zero Current Output Voltage IPR 0 – 10 A Sens IPR(min) < IP < IPR(max) – 264 – mV/A VIOUT(Q) Unidirectional; IP = 0 A – VCC x 0.
PAGE 9
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package xLLCTR-20AU PERFORMANCE CHARACTERISTICS: TA Range L, valid at TA = – 40°C to 150°C, VCC = 3.3 V, unless otherwise specif ied Characteristic Symbol Test Conditions Min. Typ. Max. Units Nominal Performance Current Sensing Range Sensitivity Zero Current Output Voltage IPR 0 – 20 A Sens IPR(min) < IP < IPR(max) – 132 – mV/A VIOUT(Q) Unidirectional; IP = 0 A – VCC x 0.
PAGE 10
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package xLLCTR-40AU PERFORMANCE CHARACTERISTICS: TA Range L, valid at TA = – 40°C to 150°C, VCC = 3.3 V, unless otherwise specif ied Characteristic Symbol Test Conditions Min. Typ. Max. Units Nominal Performance Current Sensing Range Sensitivity Zero Current Output Voltage IPR 0 – 40 A Sens IPR(min) < IP < IPR(max) – 66 – mV/A VIOUT(Q) Unidirectional; IP = 0 A – VCC x 0.
PAGE 11
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 CHARACTERISTIC PERFORMANCE xLLCTR-5AB Key Parameters Offset Voltage vs. Temperature 30 1670 20 1660 10 Offset Voltage (mV) VIOUT(Q) (mV) Zero Current Output Voltage vs.
PAGE 12
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-10AB Key Parameters Offset Voltage vs. Temperature 10 1655 5 Offset Voltage (mV) VIOUT(Q) (mV) Zero Current Output Voltage vs. Temperature 1660 1650 1645 1640 0 -5 -10 1635 -15 -50 0 50 100 150 -50 0 Temperature (ºC) 150 100 150 Sensitivity Error vs. Temperature 137 4 136 3 135 2 Sensitivity Error (%) Sensitivity (mV/A) 100 Temperature (ºC) Sensitivity vs.
PAGE 13
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-10AU Key Parameters Offset Voltage vs. Temperature 10 335 5 330 0 Offset Voltage (mV) VIOUT(Q) (mV) Zero Current Output Voltage vs.
PAGE 14
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-20AB Key Parameters Offset Voltage vs. Temperature Zero Current Output Voltage vs. Temperature 1652 1650 1650 1648 1648 Offset Voltage (mV) VIOUT(Q) (mV) 1652 1646 1644 1642 1640 1646 1644 1642 1640 1638 1638 1636 1636 1634 -50 0 50 100 1634 -50 150 0 Temperature (ºC) 100 150 100 150 Temperature (ºC) Sensitivity Error vs. Temperature Sensitivity vs.
PAGE 15
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-20AU Key Parameters Offset Voltage vs. Temperature 10 335 5 Offset Voltage (mV) VIOUT(Q) (mV) Zero Current Output Voltage vs. Temperature 340 330 325 320 315 0 -5 -10 -15 310 -50 0 100 50 -20 -50 150 0 Temperature (ºC) 5 138 4 137 3 Sensitivity Error (%) Sensitivity (mV/A) 150 100 150 Sensitivity Error vs. Temperature Sensitivity vs.
PAGE 16
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-40AB Key Parameters Offset Voltage vs. Temperature Zero Current Output Voltage vs. Temperature 1654 4 1652 2 1650 Offset Voltage (mV) 0 VIOUT(Q) (mV) 1648 1646 1644 1642 1640 -2 -4 -6 -8 -10 1638 -12 1636 -14 1634 -50 0 100 50 -16 -50 150 0 Temperature (ºC) 100 150 100 150 Temperature (ºC) Sensitivity Error vs. Temperature Sensitivity vs.
PAGE 17
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 xLLCTR-40AU Key Parameters Offset Voltage vs. Temperature Zero Current Output Voltage vs. Temperature 15 340 10 Offset Voltage (mV) 345 VIOUT(Q) (mV) 335 330 325 320 315 310 -50 5 0 -5 -10 -15 0 100 50 -20 -50 150 0 Temperature (ºC) 5 69 4 68 3 Sensitivity Error (%) Sensitivity (mV/A) 150 100 150 Sensitivity Error vs. Temperature Sensitivity vs.
PAGE 18
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 DEFINITIONS OF ACCURACY CHARACTERISTICS Sensitivity (Sens) The change in sensor IC output in response to a 1 A change through the primary conductor. The sensitivity is the product of the magnetic circuit sensitivity (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.
PAGE 19
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package APPLICATION INFORMATION Impact of External Magnetic Fields The ACS722 works by sensing the magnetic field created by the current flowing through the package. However, the sensor cannot differentiate between fields created by the current flow and external magnetic fields. This means that external magnetic fields can cause errors in the output of the sensor.
PAGE 20
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 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.
PAGE 21
High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package ACS722 Package Outline Drawing For Reference Only – Not for Tooling Use (Reference MS-012AA) Dimensions in millimeters – NOT TO SCALE Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown 8° 0° 4.90 ±0.10 1.27 0.65 8 8 1.75 0.25 0.17 3.90 ±0.10 5.60 6.00 ±0.20 A 1.04 REF 1 2 1 1.27 0.
PAGE 22
ACS722 High Accuracy, Galvanically Isolated Current Sensor IC With Small Footprint SOIC8 Package Revision History Revision Revision Date – June 10, 2014 1 October 29, 2014 2 April 29, 2015 Description of Revision Initial release.