| 摘要 |
<P>PROBLEM TO BE SOLVED: To switch whether to output an audio signal by using a BTL system or not, and to prevent a common mode choke coil which is not a signal path from having an adverse effect on the audio signal when the common mode choke coil is equipped. <P>SOLUTION: When a BTL system is not used, a switch SW1 and a switch SW2 are controlled to on-state, and a switch SW3 and a switch SW4 are controlled to off-state. Since the current of an audio signal does not flow through a common mode choke coil L3, the audio signal can be prevented from being distorted. When a BTL system is used, the switch SW1 and switch SW2 are controlled to off-state, and the switch SW3 and switch SW4 are controlled to on-state. Since the current of an audio signal does not flow through common mode choke coils L4, L5, the audio signal can be prevented from being distorted. <P>COPYRIGHT: (C)2012,JPO&INPIT |
