MICRO SPEAKER UNIT FOR MOBILE TERMINAL DEVICE

摘要

A micro speaker unit for a mobile terminal is provided to analyze impedance properties of a micro speaker to filter/reproduce reproducible frequency bands, thereby minimizing the power consumption of amplification devices having relatively large power consumption in the micro speaker unit. An impedance measurer(64) measures impedance of a micro speaker(58) as being connected to the speaker(58). A selector(62) selectively switches connection between the measurer(64) and an amplifier(56). A controller(66) controls the switching of the selector(62), analyzes the measured impedance to operate a resonant frequency of the speaker(58), and sets reproduction disability frequency bands in the speaker(58) based on the operated resonant frequency. An active filter(60) cuts off the set reproduction disability frequency bands from received voice signals.