Inrush current restraining circuit and audio device using the same

[0011]FIG. 1 is a block diagram of an audio device 1 of an exemplary embodiment of the present invention. The audio device 1 includes an audio circuit 200, a DC-blocking capacitor C1, and an inrush current restraining circuit 100. The inrush current restraining circuit 100 is connected to the audio circuit 200 via the DC-blocking capacitor C1, for restraining inrush current generated by the audio device 1. The audio circuit 200 includes a power source Vcc, a controller 10, a charging / discharging circuit 11, a voltage dividing circuit 12, a switching circuit 13, a regulator 14, a first impedance Z1 and a second impedance Z2.

[0012]The audio circuit 200 outputs an audio signal Vaudio. The DC-blocking capacitor C1 is used for blocking a DC component of the audio signal Vaudio output from the audio circuit 200, and the audio signal Vaudio without the DC component is defined as output Vout2 of the audio device 1. However, inrush current is generated due to a capacitance effect when the aud