ACS781xLR
High-Precision Linear Hall-Effect-Based
Current Sensor IC with 200 µΩ Current Conductor
FEATURES AND BENEFITS
▪ Core-less, micro-sized, 100 A continuous current package
▪ Ultra-low power loss: 200 µΩ internal conductor
resistance
▪ Immunity to common-mode field interference
▪ Greatly improved total output error through digitally
programmed and compensated gain and offset over the full
operating temperature range
▪ Industry-leading noise performance through proprietary
amplifier and filter design techniques
▪ Integrated shield greatly reduces capacitive coupling from
current conductor to die due to high dV/dt signals, and
prevents offset drift in high-side, high-voltage applications
▪ Monolithic Hall IC for high reliability
▪ 3 to 3.6 V, single supply operation
▪ 120 kHz typical bandwidth
▪ 3.6 µs output rise time in response to step input current
▪ Output voltage proportional to AC or DC currents
▪ Factory-trimmed for accuracy
▪ Extremely stable quiescent output voltage
▪ AEC-Q100 automotive qualification
PACKAGE:
7-pin PSOF package (suffix LR)
DESCRIPTION
The Allegro ACS781xLR is a fully integrated current sensor
linear IC in a new core-less package designed to sense AC and
DC currents up to 100 A. This automotive-grade, low-profile
(1.5 mm thick) sensor IC package has a very small footprint.
The Hall sensor technology also incorporates common-mode
field rejection to optimize performance in the presence of
interfering magnetic fields generated by nearby current carrying
conductors.
The device consists of a precision, low-offset linear Hall circuit
with a copper conduction path located near the die. Applied
current flowing through this copper conduction path generates
a magnetic field which the Hall IC converts into a proportional
voltage. Device accuracy is optimized through the proximity
of the primary conductor to the Hall transducer and factory
programming of the sensitivity and quiescent output voltage
at the Allegro factory.
Chopper-stabilized signal path and digital temperature
compensation technology also contribute to the stability of the
device across the operating temperature range.
High-level immunity to current conductor dV/dt and stray
electric fields, offered by Allegro proprietary integrated shield
technology for low-output voltage ripple and low-offset drift
in high-side, high-voltage applications.
The output of the device has a positive slope (>VCC / 2) when an
increasing current flows through the primary copper conduction
Not to scale
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ACS781xLR
5 IP+ VOUT 3
IP
6
IP–
GND 2
1
VCC
RF
CF
VOUT
CBYP
0.1 µF
3.3 V
Typical Application
Application 1: The ACS781xLR outputs an analog signal, VOUT , that varies linearly with the bidirectional AC or DC primary
current, IP , within the range specified. CF is for optimal noise management, with values that depend on the application.
ACS781xLR-DS, Rev. 5
MCO-0000276
February 12, 2020
