Reduction of multilayer ceramic capacitor vibration by changing the cover thickness

Vibration of multilayer ceramic capacitors (MLCCs), caused by the piezoelectricity of the dielectric material, BaTiO₃, can generate acoustic noise in electronic devices. To reduce the vibration of MLCCs, the relationship between the cover layer thickness and vibration of the MLCC was analyzed in this study. A numerical model using a finite element method was constructed for a parameter study of the cover layer. The results indicated that increasing the cover layer thickness reduced the vibration. Especially, thicker head and side covers largely reduced vibrations at the head and side surfaces of the MLCC. Increasing the thickness of the top cover reduced the entire vibration of the MLCC, while thickening the head and side covers increased top surface vibration.