Description
he Allegro
™
ACS724 current sensor IC is an economical and
precise solution for AC or DC current sensing in industrial,
automotive, 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. The current is sensed differentially in order to reject
common mode fields, improving accuracy in magnetically
noisy environments. The inherent 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 is
programmed for accuracy after packaging. 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 1.2 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
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.
Specs
Differential Hall sensing rejects common mode fields
•
1.2 mΩ primary conductor resistance for low power loss
and high inrush current withstand capability
•
Integrated shield virtually eliminates capacitive
coupling from current conductor to die, greatly
suppressing output noise due to high dv/dt transients
•
Industry-leading noise performance with greatly
improved bandwidth through proprietary amplifier and
filter design techniques
•
High bandwidth 120kHz analog output for faster
response times in control applications
•
Filter pin allows user to filter the output for improved
resolution at lower bandwidth
•
Patented integrated digital temperature compensation
circuitry allows for near closed loop accuracy over
temperature in an open loop sensor
•
Small footprint, low-profile SOIC8 package suitable for
space-constrained applications
•
Filter pin simplifies bandwidth limiting for better
resolution at lower frequencie
Application
Home office, Factory, room
