Actuator driving circuit

A drive circuit for applying a drive voltage to an actuator whose capacitance increases with an increase in the amount of the drive voltage, the drive circuit comprising:

• an output element for outputting a drive voltage in a driving waveform;
• and
• an element driving circuit for driving the output element, both of the output element and the element driving circuit having a characteristic to decrease a rising edge time period and a falling edge time period of the driving waveform in accordance with an increase in the amount of the drive voltage,
• wherein the output element includes:
• a first transistor for electrically charging the actuator;
• and
• a second transistor for electrically discharging the actuator, each of the first and second transistors having an ON resistance that decreases according to an increase in the amount of an output element driving voltage outputted form the element driving circuit to each of the first and second transistors,
• wherein each of the first and second transistors is a field-effect transistor having a source, a drain, and a gate, the source of the first transistor being connected to a voltage source, the source of the second transistor being grounded, drains of the first and second transistors being connected to one terminal of the actuator, and gates of the first and second transistors being connected to the element driving circuit, and
• wherein the element driving circuit includes:
• a control portion;
• a first pair of transistors and a first capacitor, each of the first pair of transistors being a field-effect transistor having a source, a drain, and a gate, the source of one of the first pair of transistors being connected to the voltage source, the source of the other transistor being grounded, drains of both of the first pair of transistors being connected to one terminal of the first capacitor and to the gate of the first transistor, and the gates of both of the first pair of transistors being connected to the control portion, the other terminal of the first capacitor being grounded;
• and
• a second pair of transistors and a second capacitor, each of the second pair of transistors being a field-effect transistor having a source, a drain, and a gate, the source of one of the second pair of transistors being connected to the voltage source, the source of the other transistor being grounded, drains of both of the second pair of transistors being connected to one terminal of the second capacitor and to the gate of the second transistor, and the gates of both of the second pair of transistors being connected to the control portion, the other terminal of the second capacitor being grounded.