发明名称 |
Microphone amplifier |
摘要 |
With a microphone amplifier using an operational amplifier, there has been a problem that a sensitivity of the condenser microphone is reduced by an influence of a parasitic capacitance generated at an input terminal of the operational amplifier. This invention offers a microphone amplifier having a condenser microphone that converts a sound into a voltage signal, an operational amplifier having an inverting input terminal to which the voltage signal from the condenser microphone is applied and a non-inverting input terminal to which a direct current bias voltage is applied, a capacitor connected between the inverting input terminal and an output terminal of the operational amplifier, and a resistor connected between the inverting input terminal and the output terminal of the operational amplifier.
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申请公布号 |
US2008025531(A1) |
申请公布日期 |
2008.01.31 |
申请号 |
US20070878440 |
申请日期 |
2007.07.24 |
申请人 |
SANYO ELECTRIC CO., LTD.;SANYO SEMICONDUCTOR CO., LTD. |
发明人 |
SUZUKI TATSUYA;KANETA YASUHIRO |
分类号 |
H04R3/00;H03F99/00;H03G3/00 |
主分类号 |
H04R3/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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