Magnetic field detection sensor

A magnetic field detection sensor comprising:

• a first magneto-impedance element and a second magneto-impedance element each having a magnetic material;
• a bias coil applying a bias magnetic field to a magnetic body of the first magneto-impedance element;
• a high-frequency oscillation circuit supplying high-frequency current to the magnetic body of the first magneto-impedance element and a magnetic body of the second magneto-impedance element;
• an AC bias circuit supplying AC bias current to the bias coil;
• a first detection circuit generating a first detection signal based on an impedance change of the first magneto-impedance element in a state of being applied with the bias magnetic field and an external magnetic field;
• a second detection circuit generating a second detection signal based on an impedance change of the second magneto-impedance element in a state of being applied with the external magnetic field and without the bias magnetic field;
• and
• a microcomputer having a program stored therein, wherein execution of the program controls the microcomputer to:
• calculate a magnitude and a direction of the external magnetic field based on the first detection signal and the second detection signal.