| 摘要 |
PROBLEM TO BE SOLVED: To suppress the noise generated, by a simple constitution when a volume switching is made by a plurality of switching means, with which a resistive serially connected body is bridged. SOLUTION: This electronic volume is provided with a plurality of resistors R1, R2 and R3, which are series connected respectively, and a plurality of switching means S1, S2 and S3 consisting of analog switches having a transmission gate as a constituent element. Between one side of the series connected bodies of the resistors R1, R2 and R3 and the mutual connection point of the resistors and between the other side of the series connected body and the other side of the series connected bodies are bridged by the plurality of switching means S1, S2 and S3, and the quantity of attenuation OdB or thereabouts can be accomplished by the on/off operation of the switching means S1, S2 and S3. In this case, the series connected bodies of the resistors R1, R2 and R3 are provided through bridging, and the switching noise generated by charge and discharge current when the plurality of switching means S1, S2 and S3 are in operation can be controlled. A subswitch means Sub, which is used in common with the switch means S1, S2 and S3, is provided.
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