Integrated Circuit IC of Hall Effect-Based Linear Current Sensor

Prod Model:	ACS712T

Product Description

Features and Benefits
▪ Low-noise analog signal path
▪ Device bandwidth is set via the new FILTER pin
▪ 5 µs output rise time in response to step input current
▪ 50 kHz bandwidth
▪ Total output error 1.5% at TA= 25°C, and 4% at -40°C to 85°C
▪ Small footprint, low-profile SOIC8 package
▪ 1.2 m internal conductor resistance
▪ 2.1 kVRMS minimum isolation voltage from pins 1-4 to pins 5-8
▪ 5.0 V, single supply operation
▪ 66 to 185 mV/A output sensitivity
▪ Output voltage proportional to AC or DC currents
▪ Factory-trimmed for accuracy
▪ Extremely stable output offset voltage
▪ Nearly zero magnetic hysteresis
▪ Ratiometric output from supply voltage
 
The Allegro® ACS712 provides economical and precise
solutions for AC or DC current sensing in industrial, automotive,
commercial, and communications systems. The device
package allows for easy implementation by the customer.
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. Device accuracy is optimized through the close
proximity of the magnetic signal 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 (>VIOUT(Q))
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 1.2mΩ typical, providing low power loss.
The thickness of the copper conductor allows survival of
the device at up to 5× overcurrent conditions. The terminals of
the conductive path are electrically isolated from the sensor leads
(pins 5 through 8). This allows the ACS712 current sensor to be
used in applications requiring electrical isolation without the use
of opto-isolators or other costly isolation techniques.
The ACS712 is provided in a small, surface mount SOIC8 package.
The leadframe is plated with 100% matte tin, which is compatible
with standard lead (Pb) free printed circuit board assembly processes.
Internally, the device is Pb-free, except for flip-chip high-temperature
Pbbased solder balls, currently exempt from RoHS. The device is
fully calibrated prior to shipment from the factory.