There is provided a microphone device for transmitting a collected audio signal to a receiving device wirelessly. The microphone device includes a battery, a current suppresser that is connected in series with the battery and suppresses a current from the battery and a plurality of transformers each of which is connected in series between the current suppresser and each of a plurality of loads and outputs a voltage in response to a corresponding load of the plurality of loads connected thereto based on an output of the current suppresser.