| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide the control circuit of a piezoelectric drive element (1). SOLUTION: An output signal of a first measurement circuit (4) is applied to a first input of a phase detector (5), an output signal of a logic circuit (10) or the output signal of a second measurement circuit (13) is applied to a second input of the phase detector (5), a second output signal of the logic circuit (10) is applied to the final stage (2) as an input signal, the final stage is used for supplying an AC voltage to a piezoelectric drive element (1), a loop filter (7) processes an output signal of the phase detector (5) and supplies a control signal to a voltage-controlled oscillator (6), and the output signal of the oscillator (6) is supplied to an input of logic circuit (10). A delay element (8) is installed, frequency is adjusted and efficiency of the optimum operating point of the piezoelectric driving element (1) is adjusted.</p> |
