A New Analysis Method for Frequency Response Analysis of Micro-speaker Using Equivalent Circuit and Finite Element Method

Abstract

This paper proposes a new analysis method to accurately reproduce the frequency response of micro-speakers for smartphones. The proposed analysis method combines equivalent circuit analysis and acoustic impedance analysis using the finite element method. In conventional analysis method, acoustic parameters in the equivalent circuit are determined by a heuristic procedure based on the results of acoustic impedance analysis using the finite element method, which causes a separation between measured and analyzed characteristics. On the other hand, the proposed analysis method directly applies the results of acoustic impedance analysis to the acoustic circuit part of the equivalent circuit to obtain analytical characteristics that are closer to the measured characteristics. Comparison of the analytical characteristics with the conventional analysis method demonstrates that the resonance frequencies in the measured characteristic can be reproduced more accurately.