Sensor device and damping force adjustable suspension system

A sensor device comprising:

• an LC oscillation circuit including a coil in which an inductance changes according to a displacement amount of an object and a DC resistor changes according to a temperature, and an oscillation unit including an LC resonance capacitor electrically connected to the coil;
• and
• a switching unit including a switch that switches whether to electrically connect one end of the coil to a predetermined DC potential, wherein
• when the switch is off, the LC oscillation circuit is in a first state in which an AC signal whose frequency changes according to the displacement amount of the object is output, and
• when the switch is on, the LC oscillation circuit stops oscillation and is in a second state in which a DC voltage whose voltage value changes according to the temperature of the coil is output from a common connection point between a predetermined resistor that is a component of the oscillation unit and other end of the coil.