| 摘要 |
PROBLEM TO BE SOLVED: To provide a power saving circuit having an excellent response characteristic at resuming power supply to an AF amplifier.SOLUTION: A power saving circuit 1 is provided between an AF amplifier 4 and a control part 6. The control part 6 sets a power saving mode, which halts power supply to the AF amplifier 4 in a case a reception signal does not satisfy a predetermined condition for a predetermined period, outputs a setting signal for setting the AF amplifier 4 into a shutdown state, and outputs a release signal in a case of releasing the power saving mode. The AF amplifier 4 includes a power supply input terminal 42 having a smoothing capacitor 41 for eliminating power supply noise from a power supply 11, and a setting terminal 43 for setting the shutdown state. The power saving circuit 1 switches, a circuit for charging the smoothing capacitor 41 by inputting a setting signal from the control part 6 not only to the setting terminal 43 but also to the power supply input terminal 42, and a circuit for supplying power by inputting the release signal from the control part 6 to the setting terminal 43. Thus, a response characteristic regarding audio output at power supply resume is improved. |
