ACS709
Description
The Allegro
®
ACS709 current sensor IC provides economical
and precise means for current sensing applications in industrial,
automotive, commercial, and communications systems. The
device is offered in a small footprint surface mount package
that allows easy implementation in customer applications.
The ACS709 consists of a precision linear Hall sensor integrated
circuit with a copper conduction path located near the surface
of the silicon die. Applied current flows through the copper
conduction path, and the analog output voltage from the Hall
sensor IC linearly tracks the magnetic field generated by the
applied current. The accuracy of the ACS709 is maximized
with this patented packaging configuration because the Hall
element is situated in extremely close proximity to the current
to be measured.
High level immunity to current conductor dV/dt and stray
electric fields, offered by Allegro proprietary integrated shield
technology, guarantees low output ripple and low offset drift
in high-side applications.
The voltage on the Overcurrent Input (VOC pin) allows
customers to define an overcurrent fault threshold for the
device. When the current flowing through the copper conduction
path (between the IP+ and IP– pins) exceeds this threshold,
ACS709-DS
Features and Benefits
Industry-leading noise performance with 120 kHz
bandwidth through proprietary amplifier and filter
design techniques
Integrated shield greatly reduces capacitive coupling
from current conductor to die due to high dV/dt, and
prevents offset drift in high-side applications
Small footprint surface mount QSOP24 package
2100 V
RMS
isolation voltage between primary current
path and sensor IC electronics
1.1 m primary conductor resistance for low power loss
User-settable Overcurrent Fault level
Overcurrent Fault signal typically responds to an
overcurrent condition in < 2 s
Filter pin capacitor sets analog signal bandwidth
±2% typical output error
3 to 5.5 V, single supply operation
Factory trimmed sensitivity, quiescent output voltage,
and associated temperature coefficients
Chopper stabilization results in extremely stable
quiescent output voltage
Ratiometric output from supply voltage
High Bandwidth, Fast Fault Response Current Sensor IC
In Thermally Enhanced Package
Continued on the next page…
Typical Application
R
H
, R
L
Sets resistor divider reference for V
OC
C
F
Noise and bandwidth limiting filter capacitor
C
OC
Fault delay setting capacitor, 22 nF maximum
A
Use of capacitor required
B
Use of resistor optional
Package: 24 pin QSOP (suffix LF)
Approximate Scale
1
2
3
4
5
6
7
8
9
10
11
12
IP+
IP+
IP+
IP+
IP+
IP+
IP–
IP–
IP–
IP–
IP–
IP–
22
21
20
19
18
17
16
15
NC
NC
FAULT_EN
VOC
VCC
FAULT
VIOUT
FILTER
VZCR
GND
NC
NC
ACS709
0.1 F
C
OC
C
F
330 k
1 nF
V
IOUT
Fault_EN
V
CC
R
H
R
L
I
P
B
A
24
23
14
13
