Current sensor

A current sensor comprising a magnetic detecting bridge circuit formed of four magneto-resistance effect elements with a resistance value varied by application of an induced magnetic field from a current to be measured, the four magneto-resistance effect elements having a same resistance change rate, each of the four magneto-resistance effect elements including:

• a self-pinned type ferromagnetic fixed layer formed of a first ferromagnetic film and a second ferromagnetic film anti-ferromagnetically coupled to each other;
• a nonmagnetic intermediate layer;
• and
• a soft magnetic free layer,
• wherein the magneto detecting bridge circuit has an output between two of the four magneto-resistance effect elements, magnetization directions of the ferromagnetic fixed layers of the two magneto-resistance effect elements being different from each other by 180°,
• wherein the magnetic detecting bridge circuit has a wiring symmetrical to a power supply point,
• and wherein the magnetic detecting bridge circuit measures the current to be measured by the outputs of the four magneto-resistance effect elements which are in proportion to the induced magnetic field.