| 摘要 |
PURPOSE:To eliminate switching noise without cutting DC components by applying a blanking pulse, which has a gentle trailing dege, to an output circuit which directly connected to the switching amplifier of a regenerative amplifier, etc., of a sound recoder. CONSTITUTION:Feedback circuit 15 including feedback capacity C11 and output circuit 14 are directly connected to output terminal 16 of switching amplifier 13, and at a amplifier 13 driving time, blanking pulse V20 which has a gnetle transition answer of the trailing edge is applied to output circuit 14 from blanking pulse generator circuit 20 until capacity C11 reaches a balance voltage to stabilize output V16 of amplifier 13. Therefore, circuit 14 is cut off; and after the output of amplifier 13 is stabilized, output V17 of circuit 14 rises gradually, and as a result, the switching noise at an operation start time can be eliminated. |
