General

Closed-loop Hall current sensor is also called Hall magnetic balancing current sensor. It incorporates the mentioned theory with magnetic balancing theory. In other words, the ferromagnetic field concentrator concentrates the magnetic field generated by primary current and applies it to the Hall component. Then the voltage signal output from Hall component is amplified and becomes the input of power amplifier. The offset current output flows through the secondary compensating coil. The magnetic field generated by secondary coil is opposite to the field generated by primary current. In such way, the primary field is compensated and the Hall output is reduced gradually. When the primary field is equivalent to thesecondary one and the offset current keeps stable, it is the magnetic balancing.This circuit mainly consists of electromagnetism conversion component, circuit amplifier and drive compensating circuit.