A Hall Effect linear current sensor is a device used to measure electric current by leveraging the Hall Effect phenomenon. The Hall Effect is the production of a voltage difference (Hall voltage) across an electrical conductor, transverse to an electric current in the conductor and an applied magnetic field perpendicular to the current. The sensor operates on this principle to accurately measure the current flowing through a conductor without physically interrupting the circuit.
Here's how a Hall Effect linear current sensor typically works:
Hall Effect Sensor Element: The core component of the sensor is a Hall Effect sensor element, which is usually a thin semiconductor material strip or a Hall Effect integrated circuit (IC). The strip is placed perpendicular to the current flow direction. When a current passes through the conductor, it generates a magnetic field around the conductor according to Ampere's circuital law.
Magnetic Field Detection: As the current flows through the conductor, the magnetic field is present in the proximity of the Hall Effect sensor element. The Hall Effect sensor element is sensitive to this magnetic field.
Hall Voltage Generation: When the magnetic field is applied perpendicular to the current-carrying conductor and the Hall Effect sensor element, it induces an electric potential difference, known as the Hall voltage, across the sensor element. The Hall voltage is directly proportional to the product of the current flowing through the conductor and the strength of the magnetic field.
Measurement and Calibration: The Hall voltage is typically very small and needs to be amplified and calibrated for accurate current measurements. The sensor includes an amplifier circuit to amplify the Hall voltage signal. Additionally, calibration is done to correlate the output voltage of the sensor with the actual current flowing through the conductor.
Output and Signal Processing: After calibration and amplification, the sensor provides an output voltage proportional to the current being measured. This output can be an analog voltage or a digital signal, depending on the sensor design.
Isolation and Protection (Optional): Some Hall Effect current sensors may have built-in isolation and protection mechanisms to ensure safe operation in various applications, particularly in high-voltage systems.
In summary, a Hall Effect linear current sensor measures the current by detecting the magnetic field produced by the current flow using a Hall Effect sensor element. It then converts this magnetic field into a Hall voltage, which is proportional to the current. This analog or digital output is then further processed and calibrated to provide an accurate representation of the current passing through the conductor without any physical contact with the current-carrying wire.