Method for attenuating interference frequencies in piezoelectric transducers

摘要

Method for attenuating interference frequencies in piezoelectric transducers (PW) above the frequencies for the useful range, in particular in integrated telephone circuits. The object of the present invention is to reduce the sensitivity of piezoelectric transducers (PA) above the range used for speech to such an extent that no further impairment occurs when calls are made. This is achieved in that a filter which attenuates the interference frequencies is formed by connecting active or passive components (RV; L, RL; C, RC; ATP) upstream in conjunction with the transducer (PW). This method is preferably used in telephones with an integrated speech circuit. <IMAGE>