An assembly that includes a target component mounted for rotation about an axis, a sensor mounted adjacent the inner member and directed toward the inner member to measure the rotational speed of the target component and an outer component interposed between the sensor and the target component. Low magnetic permeability of the outer component is assured by appropriate selection of the material, maintaining the concentration of martensite in the outer component below a reference concentration as indicated by certain reference indices such as the Instability Function, and/or by maintaining the temperature at which a stamping operation is performed on the inner member above a pre-determined temperature.
A magnetic sensor apparatus includes a semiconductor substrate and a magnetic impedance device for detecting a magnetic field. The magnetic impedance device is disposed on the substrate. The magnetic sensor apparatus has minimum size and is made with low manufacturing cost. Here, the magnetic impedance device detects a magnetic field in such a manner that impedance of the device is changed in accordance with the magnetic filed when an alternating current is applied to the device and the impedance is measured by an external electric circuit.
A magnetic sensor apparatus includes a semiconductor substrate and a magnetic impedance device for detecting a magnetic field. The magnetic impedance device is disposed on the substrate. The magnetic sensor apparatus has minimum size and is made with low manufacturing cost. Here, the magnetic impedance device detects a magnetic field in such a manner that impedance of the device is changed in accordance with the magnetic filed when an alternating current is applied to the device and the impedance is measured by an external electric circuit.