Vibration Reduction of MLCCS Using Vibration-Canceling Effects of Poling Process

MLCC vibrates due to its piezoelectric characteristics and it makes circuit board vibrate and lead to acoustic noise. In order to reduce vibration, piezoelectric coefficient should be reduced. In this study, poling process was used to decrease piezoelectric coefficient. Due to the electrostriction coefficient, response at fundamental frequency can be cancelled by applying voltage to opposite direction. Through the experiment, vibration-cancelling voltage increases as the poling voltage increases. Also, vibration-cancelling voltage increase inversely proportion to MLCC’s capacitance. By applying proper DC bias after poling process, vibration can be reduced.