Precise current sensor for power electronic devices

Precise current measurements are necessary for the operation of power electronic devices to determine the current state. Today, current sensors based on the Hall effect are used. These current sensors lack a satisfying resolution in the lower part of their measurement range and there are troubles with offsets. When compared to the conventional current sensors, the proposed topology shows the following advantages: a very high resolution over the whole measurement range, reducing offsets to a minimum due to an active offset-compensation by an analog/digital chopper/de-chopper, an excellent suppression of 1/f noise, and an extremely low noise density (35 nV/radic(Hz) ) down to DC. Common current sensors may be replaced with this technology whose output is likewise analog. A further advantage is that there are fewer demands concerning the power supply, as only a single source is required.