Mounting condition influence on the vibration of multi-layer ceramic capacitor

Multi-layer ceramic capacitor is essential passive electronic component because of its tiny size and large capacitance. However, electromechanical properties of the main dielectric material, BaTiO₃, makes mechanical vibration of the component. Because of the vibration, electronic devices such as smartphones or laptop computers generate high-pitched acoustic noise. Acoustic noise problem can be separated into three parts. One is the capacitor itself which act as vibration source, another is solder or lead-frame which act as vibration transfer path, and the other is board which act as acoustic noise source due to its resonance. In this study, we focused on the vibration transfer path to reduce the acoustic noise in two ways. Firstly, solder shape influence to the board vibration was analyzed. Next, from the constructed finite element analysis, effective lead frame shape was designed. Vibration reduction performance of newly designed lead frame was validated from the simulation results. Results show that newly designed lead frame can reduce the vibration of the circuit board comparing with the solder mounting and original shape of leas frame.