ACS722
High Accuracy, Galvanically Isolated Current Sensor IC
With Small Footprint SOIC8 Package
FEATURES AND BENEFITS
• 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
Continued on the next page…
DESCRIPTION
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,
Continued on the next page…
Package: 8-pin SOIC (suff ix LC)
CB Certif icate Number:
US-22334-A1-UL
Approximate Scale 1:1
1
+I
P
2
I
P
8
IP+
VCC
ACS722
7
IP+
VIOUT
6
C
L
4
IP–
GND
5
C
BYPASS
0.1 µF
3
–I
P
IP–
BW_SEL
The ACS722 outputs an analog
signal, V
IOUT
, that changes,
proportionally, with the
bidirectional AC or DC primary
sensed current, I
P
, 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.
Typical Application
ACS722-DS, Rev. 2
ACS722
High Accuracy, Galvanically Isolated Current Sensor IC
With Small Footprint SOIC8 Package
Description (continued)
which is compatible with standard lead (Pb) free printed circuit
board 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.
Features and Benefits (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
Selection Guide
Part Number
ACS722LLCTR-05AB-T
2
ACS722LLCTR-10AU-T
2
ACS722LLCTR-10AB-T
2
ACS722LLCTR-20AU-T
2
ACS722LLCTR-20AB-T
2
ACS722LLCTR-40AU-T
2
ACS722LLCTR-40AB-T
2
1
Contact Allegro
2
Variant
I
PR
(A)
±5
10
±10
20
±20
40
±40
Sens(Typ)
at V
CC
= 3.3 V
(mV/A)
264
132
66
33
T
A
(°C)
Packing
1
-40 to 150
Tape and Reel, 3000 pieces per reel
for additional packing options.
not intended for automotive applications.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
ACS722
High Accuracy, Galvanically Isolated Current Sensor IC
With Small Footprint SOIC8 Package
SPECIFICATIONS
Absolute Maximum Ratings
Characteristic
Supply Voltage
Reverse Supply Voltage
Output Voltage
Reverse Output Voltage
Operating Ambient Temperature
Junction Temperature
Storage Temperature
Symbol
V
CC
V
RCC
V
IOUT
V
RIOUT
T
A
T
J
(max)
T
stg
Range L
Notes
Rating
6
–0.1
25
–0.1
–40 to 150
165
–65 to 165
Units
V
V
V
V
°C
°C
°C
Isolation Characteristics
Characteristic
Dielectric Strength Test Voltage
Symbol
V
ISO
Notes
Agency type-tested for 60 seconds per UL 60950-1 (edition.
2). Production tested at V
ISO
for 1 second, in accordance
with UL 60950-1 (edition. 2).
Maximum approved working voltage for basic (single)
isolation according UL 60950-1 (edition 2).
Minimum distance through air from IP leads to signal leads.
Minimum distance along package body from IP leads to
signal leads.
Rating
2400
420
297
3.9
3.9
Unit
V
RMS
V
PK or
VDC
V
RMS
mm
mm
Working Voltage for Basic Isolation
Clearance
Creepage
V
WVBI
D
cl
D
cr
Thermal Characteristics
Characteristic
Package Thermal Resistance
(Junction to Ambient)
Package Thermal Resistance
(Junction to Lead)
Symbol
R
θJA
R
θJL
Test Conditions*
Mounted on the Allegro 85-0593 evaluation board with 400 mm
2
of
4 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.
Mounted on the Allegro ASEK 722 evaluation board.
Value
23
Units
ºC/W
5
ºC/W
*Additional thermal information available on the Allegro website.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
RF/Wirelessly
京公网安备 11010802033920号
EEWORLD
