POSITION DETECTOR

摘要

A position detector includes a coil (1) and a conductive body (2) or a magnetic body (3) whose matched portion (p) has an area changing in accordance with change of the position of an object to be detected. The position detector further includes a resistor (6), a capacitor (4), a reverse-output comparator (5), and a timing circuit (50a) for regulating a continuous oscillation operation period (T) constant. A change of the position of the object to be detected is detected as a change of a time width (t) until an output of the comparator (5) is reversed to a high level at the timing from the start to near end of the period (T). A resistance value of the resistor (6) is set, so that the change of the time width (t) has a minimum value with respect to the change of the resistance value of the resistor (6) under an estimated temperature. It is possible to improve the temperature characteristic and linearity of output against the change of the position.