Semiconductor device and method of controlling electrostatic actuator

A semiconductor device controlling an electrostatic actuator having first and second electrodes formed so as to come close to each other by electrostatic attraction against elastic force, the semiconductor device comprising:

• a voltage generation unit generating different types of voltages applied to the first and second electrodes;
• a control unit controlling voltages generated by the voltage generation unit to be applied to the first and second electrodes;
• and
• a capacitance detection unit detecting a voltage of the first or second electrode to detect a capacitance between the first and second electrodes;
• the control unit configured to sequentially perform:
• applying a first voltage between the first and second electrodes;
• applying a second voltage smaller than the first voltage between the first and second electrodes;
• and
• switching one of the first electrode or the second electrode to a high impedance state and then changing a voltage applied to the other;
• and
• the capacitance detection unit configured to detect the amount of change in voltage of the first or second electrode to detect a capacitance between the first and second electrodes.