Method for extending the measuring range of an absolute angle in magnetic-field sensors

In modern angle measurement methods, magnetic field sensors are operated in a measuring bridge apparatus. An absolute angle measurement over an angular range of 360° using AMR sensors is possible only at a high cost. With Hall or GMR sensors, it is possible to expand the range to 360°; with AMR sensors, a measurement range of 180° is possible. The invention relates to a method for expanding the absolute angle measurement range in magnetic field sensors. Through the use of an evaluation circuit (), various method steps are carried out; first, the ratio of two phase-shifted input values is determined, for example sine signals or cosine signals of the voltage (). The ratio of the phase-shifted input values () to each other is combined with an offset C. The predeterminable offset C permits the expansion () of the angle measurement range of magnetic field sensors to a full 360° rotation () or a multiple thereof.