Liquid ejection device and liquid ejection surgical instrument

1. A liquid ejection device comprising:

a drive waveform generator generating a drive waveform signal;

a modulator performing pulse modulation on a signal from the drive waveform generator to provide a modulated signal;

a digital power amplifier performing power amplification on the modulated signal to provide an amplified digital signal;

a lowpass filter smoothing the amplified digital signal to provide a drive signal of an actuator;

a compensator advancing a phase of the drive signal to provide a negative feedback signal;

a subtractor providing a differential signal between the drive waveform signal and the negative feedback signal as an input signal to be inputted to the modulator; and

an inverse filter provided between the drive waveform generator and the subtractor,

wherein the inverse filter changing an attenuation start frequency when a number of the actuators which are driven is changed.

2. The liquid ejection device according to claim 1 , wherein the inverse filter increasing the attenuation start frequency when the number of the actuators which are driven are increased.

3. The liquid ejection device according to claim 2 , wherein the inverse filter correcting a frequency characteristic of a closed loop formed of the modulator, the digital power amplifier, the lowpass filter, a capacitance of the actuator, and the compensator so as to be constant in a predetermined frequency domain.

4. The liquid ejection device according to claim 1 , wherein the inverse filter correcting a frequency characteristic of a closed loop form of the modulator, the digital power amplifier, the lowpass filter, a capacitance of the actuator, and the compensator so as to be constant in a predetermined frequency domain.