ACS712 provides economical and precise solutions for AC or DC current sensing in industrial, commercial, and communications systems. ACS712 was designed as a fully integrated, Hall-effect-based linear sensor IC that can sense up to 30A of current flow. This device operates at a supply voltage of 5V in which output is proportional to AC or DC current. The devices can be survived up to 5 times overcurrent conditions due to their thick copper conductor and signal traces.
Using the Indirect Sensing method ACS712 calculates the current. In order to sense current a liner, low-offset, precise Hall sensor circuit is used in this IC. This device was placed at the surface of the IC on a copper conduction path. When the applied current flows through this copper conduction path it generates a magnetic field sensed by the Hall effect sensor. Hall Sensor generates a voltage proportional to the sensed magnetic field, used to measure current. The present output current signal is read via the analogue I / O port of a microcontroller or an Arduino.
ACS712 is used in a wide range of applications where sensing and controlling current flow is fundamental such as over-current protection, battery, switching mode power supplies, digital watt meters, etc. The range of the magnetic signal to the Hall sensor decides the accuracy of the device. Closer the magnetic signal higher the accuracy. ACS712 was designed as a compact-sized, surface mount SOIC8 package. In this ACS712 Current Sensor IC, Pin-1 to Pin-4 forms the conduction path where the current is sensed. Pin-5 represents the signal ground pin. Pin-6 indicates the FILTER pin by an external capacitor to set the bandwidth. Pin-7 is the analogue output pin. Pin-8 is the power supply pin.