Datasheet ACS724 (Allegro)

ACS724 Automotive-Grade, Galvanically Isolated Current Sensor IC with Common-Mode Field Rejection in a Small-Footprint SOIC8 Package FEATURES AND BENEFITS DESCRIPTION
• AEC-Q100 qualified The Allegro™ ACS724 current sensor IC is an economical and • Differential Hall sensing rejects common-mode fields precise solution for AC or DC current sensing in industrial, • 1.2 mΩ primary conductor resistance for low power loss automotive, commercial, and communications systems. The and high inrush current withstand capability small package is ideal for space-constrained applications • Integrated shield virtually eliminates capacitive while also saving costs due to reduced board area. Typical coupling from current conductor to die, greatly applications include motor control, load detection and suppressing output noise due to high dv/dt transients management, switched-mode power supplies, and overcurrent • Industry-leading noise performance with greatly fault protection. improved bandwidth through proprietary amplifier and The device consists of a precise, low-offset, linear Hall filter design techniques sensor circuit with a copper conduction path located near the • High-bandwidth 120 kHz analog output for faster surface of the die. Applied current flowing through this copper response times in control applications conduction path generates a magnetic field which is sensed • Filter pin allows user to filter the output for improved by the integrated Hall IC and converted into a proportional resolution at lower bandwidth voltage. The current is sensed differentially in order to reject • Patented integrated digital temperature compensation common-mode fields, improving accuracy in magnetically circuitry allows for near closed loop accuracy over noisy environments. The inherent device accuracy is optimized temperature in an open loop sensor through the close proximity of the magnetic field to the Hall • Small-footprint, low-profile SOIC8 package suitable for transducer. A precise, proportional voltage is provided by the space-constrained applications low-offset, chopper-stabilized BiCMOS Hall IC, which is • Filter pin simplifies bandwidth limiting for better programmed for accuracy after packaging. The output of the resolution at lower frequencies device has a positive slope when an increasing current flows Continued on the next page… through the primary copper conduction path (from pins 1 and 2, to pins 3 and 4), which is the path used for current sensing. TÜV America The internal resistance of this conductive path is 1.2 mΩ typical, Certificate Number: U8V 18 02 54214 041 providing low power loss. CB 14 11 54214 031
CB Certificate Number:
The terminals of the conductive path are electrically isolated
US-32848-UL
from the sensor leads (pins 5 through 8). This allows the
PACKAGE: 8-Pin SOIC (suffix LC)
ACS724 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. Not to scale Continued on the next page… 1 8 IP+ VCC +IP ACS724
The ACS724 outputs an
2 7
analog signal, VIOUT , that
IP+ VIOUT
changes proportionally with the bidirectional AC
I
or DC primary sensed
P CBYPASS 3 6 0.1 µF
current, IP , within the
IP– FILTER
specified measurement
–I
range. The FILTER pin
P C CLOAD
can be used to decrease
F 4 5
the bandwidth in order
IP– GND 1 nF
to optimize the noise performance. Typical Application
ACS724-DS, Rev. 15 June 3, 2019 MCO-0000227