ACS720
High Accuracy, Dual Fault, Galvanically Isolated
Current Sensor in SOIC16 Wide-Body Package
FEATURES AND BENEFITS
DESCRIPTION
• Differential current sensing cancels common mode fields,
simplifying PCB layout
• Two user-settable faults for fast short-circuit protection
and slower overcurrent detection
The ACS720 is a high accuracy Hall-effect-based current
sensor IC with multiple programmable fault levels intended
for industrial and consumer applications with a focus on motor
control and power inverter stage applications.
• Industry-leading noise performance with greatly improved
bandwidth through proprietary amplifier and filter design
techniques
• Patented integrated digital temperature compensation
circuitry allows high accuracy over temperature in an
open loop sensor
•ꢀ 1.0ꢀmΩꢀprimaryꢀconductorꢀresistanceꢀforꢀlowꢀpowerꢀlossꢀ
and high inrush current-withstanding capability
• Small footprint, low-profile SOIC16 package suitable for
space-constrained applications
• Integrated shield virtually eliminates capacitive coupling
from current conductor to die due to high dV/dt voltage
transients
• 5 V single supply operation with 0-3 V output swing
• Output voltage proportional to AC or DC current
• Factory-trimmed sensitivity and quiescent output voltage
for improved accuracy
• 3600 Vrms Dielectric Strength certified under UL60950-1
• High PSRR for noisy environments
One of the key benefits of the ACS720 is to provide high
isolation with a reduced bill of materials made possible by
the proprietary IC SOIC16W package. The ACS720 works
off of a single 5 V supply while maintaining an output voltage
swing from 0 to 3 V, with a stable zero current output of 1.5 V.
This allows the ACS720 to operate off of a 5 V supply while
having an output which is compatible with typical 3.3VADCs
foundonmanyMCUs.Furthermore,theACS720’shighPSRR
rejects the noise often found on the supplies in the power
section of the PCB or system, maintaining high accuracy in
noisy environments.
The device has dual fault functions that are user configurable.
Fastandslowfaultoutputallowforshort-circuitandovercurrent
fault detection. Auser-created resistor divider from the power
supply of the ACS720 is used to set the fault level. The fault
outputs are open drain, allowing the user to pull them up to
a compatible voltage for the MCU. The open-drain outputs
also allow for implementing a simple logical OR of multiple
sensor fault outputs.
PACKAGE:
TheACS720alsointegratesdifferentialcurrentsensing,which
rejects external magnetic fields, greatly simplifying board
layout in 3-phase motor applications.
16-Pin SOICW
(suffix LA)
CB Certificate Number:
US-23711-A2-UL
Not to scale
Continued on the next page…
VCC
VOC_F
VOC_S
DIGITAL SYSTEM
FAULT_F
Voltage
Reference
ADC
EEPROM &
Control Logic
Temp.
Sensor
To All
Subcircuits
Fault
Setpoint
Control
DAC
Programming
Control
Fast Fault
Hall
Driver
FAULT_S
Fault Filter
Logic
IP+
Slow Fault
Sensitivity
Control
Offset
Control
DAC
Dynamic Offset
Cancellation
RF(INT)
Analog
Filters
VIOUT
IP–
GND
FILTER
Figure 1: Functional Block Diagram
ACS720-DS, Rev. 8
MCO-0000183
December 7, 2018