| 摘要 |
PURPOSE:To attain direct drive with a digital signal, by alternately laminating n-set of piezoelectric ceramics and (n+1) sets of electrode and applying each bit output of n-bit digital signals between one electrode and the other electrode. CONSTITUTION:Longitudinal effect piezoelectric ceramics 13 and electrodes 14 are alternately overlapped to form a piezoelectric oscillator. Digital input terminals 15a 15e are led out from the electrodes 14 and each bit output of a digital signal is connected between the terminal 15a or 15e and the other terminals. Since a mechnical distortion y1 toward the thickness direction of the ceramics 13 is proportional to an electric field E, the relation of u1=k1.V/d is obtained, where V is a voltage between the electrodes, d is an interval between the electrodes and K1 is a proportional constant. Thus, the inverval d is kept constant and the voltage between the electrodes is taken as Vab=V0, Vbc=2V0, Vcd=4V0 and Vde=8V0, then oxillation corresponding to an input digital signal can be obtained. |
