HallinOne®-Current Sensor Technology
Current sensors measure the magnetic field generated by the electric current flow. Hall sensors implemented in standard CMOS are applied.Current sensors measure the magnetic field generated by the electric current flow. Hall sensors implemented in standard CMOS are applied.
Due to their high sensitivity and their capacity to compensate offsets and temperature dependence through integrated electronics, the sensors allow for forgoing magnetic-field concentrating devices like ferrite cores. This way hysteresis and saturation effects can be avoided and plain design and high integration ability achieved.
In order to compensate external magnetic fields, like the earth’s field, a minimum of two magnetic field sensors are required to measure current. The used Hall elements measure only the Z component of the magnetic field, which is perpendicular to the chip surface. While the Z components of external noise fields have the same value and sign in both sensors, they have opposite signs in a field created by electric current. This way the current can be measured without interference. The integration of both sensors in one chip allows a compact design and an exact reproducibility of their geometry. A single calibration measurement can compensate the positioning errors of the conductor, which is not integrated on the chip.