| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply improved for an active noise reduction headset. <P>SOLUTION: A power supply 32 includes a battery power supply 78 for supplying power, and a voltage conversion circuit 70. The voltage conversion circuit converts power into an input voltage supplied to another circuit. The voltage conversion circuit varies the input voltage in response to a load current derived from the power supply by another circuit. In another mode, when the load current derived from the power supply by an outside circuit is equal to or less than a threshold value for a predetermined time amount, a shutoff circuit making the outside circuit a low power consumption state is included. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
