| 摘要 |
The invention relates to a switched low-energy consumption amplifier for a piezoelectric element, which comprises: (a) an inductor, which together with the capacitance of said piezoelectric element forms an LC circuit; (b) a battery connected to said LC circuit; (c) a set of controlled switches capable of connecting and disconnecting circuit components at a rate which is significantly higher than the frequency of an input signal to said circuit; (d) a comparator for receiving an input signal, comparing a present voltage value of the input signal with a present voltage value over said piezoelectric element or a part thereof, and conveying an indication regarding said comparison to a switching control unit; and (e) a switching control unit for receiving said indication from said comparator, and determining repeatedly every period P, which is significantly shorter than the period of the highest frequency included within said input signal, whether the piezoelectric element should be charged or discharged, and accordingly providing a control signal to each of said controlled switches with a certain duty cycle of P, thereby causing energy transfer from the piezoelectric element to the inductor and/or battery, or from the battery and/or inductor to the piezoelectric element, thereby retaining the energy within the amplifier circuit. |
