Method and device for measuring a magnetic field and the temperature of a magneto-resistive transducer

A non-transitory information recording medium, containing program instructions to be executed by an electronic computer for measuring a first magnetic field and the temperature of a magneto-resistive transducer, the intensity of the first magnetic field being unknown, comprising:

• producing, by the magneto-resistive transducer, a measurement signal dependent on the intensity of the first magnetic field, the measurement signal also being dependent on the temperature of the magneto-resistive transducer,
• establishing a measurement of the intensity of the first magnetic field on the basis of the measurement signal produced, and
• establishing a measurement of the temperature of the magneto-resistive transducer,
• generating, at the same time as the first magnetic field, a second magnetic field, on the basis of a generator electrically insulated from the magneto-resistive transducer, whose characteristics are known, the second magnetic field being combined with the first magnetic field to form a resultant magnetic field which is measured by the magneto-resistive transducer,
• extracting from the measurement signal produced, the component of this signal which is dependent solely on the second magnetic field alone, using the known characteristics of the second magnetic field, and establishing the temperature of the magneto-resistive transducer on the basis of the component extracted.

A device for measuring a first magnetic field and the temperature of a magneto-resistive transducer, the intensity of the first magnetic field being unknown, the magneto-resistive transducer capable of producing a measurement signal dependent on the intensity of the first magnetic field, the measurement signal also being dependent on the temperature of the magneto-resistive transducer, the device comprising:

• a processing unit configured to:
• establish a measurement of the intensity of the first magnetic field on the basis of the measurement signal produced, and
• establish a measurement of the temperature of the magneto-resistive transducer, and
• a generator electrically insulated from the magneto-resistive transducer, configured to generate, at the same time as the first magnetic field, a second magnetic field whose characteristics are known, their second magnetic field being combined with the first magnetic field to form a resultant magnetic field which is measured by the magneto-resistive transducer, wherein the processing unit is further configured to:
• extract, from the measurement signal produced, the component of this signal which is dependent solely on the second magnetic field alone, using the known characteristics of the second magnetic field, and
• establish the temperature of the magneto-resistive transducer on the basis of the component extracted.

A current sensor comprising:

• an electrical conductor in which a current to be measured flows,
• a measurement device for measuring a first magnetic field and the temperature of a magneto-resistive transducer, the magneto-resistive transducer capable of producing a measurement signal dependent on the intensity of the first magnetic field, the measurement signal also being dependent on the temperature of the magneto-resistive transducer, the first magnetic field generated by the current to be measured flowing in the electrical conductor, the intensity of the first magnetic field being unknown, the measurement device comprising:
• a processing unit configured to:
• establish a measurement of the intensity of the first magnetic field on the basis of the measurement signal produced, and
• establish a measurement of the temperature of the magneto-resistive transducer, and
• a generator, electrically insulated from the magneto-resistive transducer, configured to generate, at the same time as the first magnetic field, a second magnetic field whose characteristics are known, the second magnetic field being combined with the first magnetic field to form a resultant magnetic field which is measured by the magneto-resistive transducer,
• wherein the processing unit is further configured to:
• extract, from the measurement signal produced, the component of this signal which is dependent solely on the second magnetic field alone, using the known characteristics of the second magnetic field,
• establish the temperature of the magneto-resistive transducer on the basis of the component extracted,
• wherein the generator further includes a conducting line generating the second magnetic field when it is traversed by a known current, and a current source connected electrically to the conducting line and able to produce the known current in this conducting line;
• and
• wherein the electrical conductor and the conducting line from just a single current line in which the known current of the current source is superimposed with the current to be measured so as to generate the first and second magnetic fields at the same time.