Variable gain circuit
    15.
    发明专利

    公开(公告)号:JP5308243B2

    公开(公告)日:2013-10-09

    申请号:JP2009139290

    申请日:2009-06-10

    IPC分类号: H03G3/10 H03F3/193 H03F3/345

    摘要: There is provided a variable gain circuit system which is inductorless and capable of achieving a high gain and a wide band by elements for achieving variable gain to prevent decreasing a gain or deteriorating the band. The variable gain circuit includes: transistors; a resistor connected as a load of each transistor; a voltage source applying a bias voltage to each gate of the transistors; a switch selectively connecting the voltage source or a ground potential to each gate of the transistors in accordance with gain setting; and a current source connected to a common input. A drain of each transistor is connected to an input of a circuit in a subsequent stage.

    Transimpedance amplifier, integrated circuit, and system
    18.
    发明专利
    Transimpedance amplifier, integrated circuit, and system 有权
    转换放大器,集成电路和系统

    公开(公告)号:JP2011254382A

    公开(公告)日:2011-12-15

    申请号:JP2010127919

    申请日:2010-06-03

    发明人: UMEDA DAISUKE

    IPC分类号: H03F3/08 H03F3/68

    摘要: PROBLEM TO BE SOLVED: To achieve increase in parasitic capacitance by a plurality of feedback resistors and wiring length of an input node.SOLUTION: The integrated circuit has a first transimpedance amplifier and a second transimpedance amplifier. In this integrated circuit, when one of the first transimpedance amplifier and the second transimpedance amplifier enters an operational state, the other enters a non-operational state. The first transimpedance amplifier and the second transimpedance amplifier share an input transistor. The first transimpedance amplifier has a first resistor provided between its feedback node and an input node connected to the input transistor. The second transimpedance amplifier has a second resistor provided between its feedback node and the first resistor. The feedback resistor of the second transimpedance amplifier is constituted by connecting the first resistor and the second resistor in series.

    摘要翻译: 要解决的问题:通过多个反馈电阻器和输入节点的布线长度来实现寄生电容的增加。 解决方案:集成电路具有第一跨阻抗放大器和第二跨阻抗放大器。 在该集成电路中,当第一跨阻抗放大器和第二跨阻抗放大器之一进入工作状态时,另一个进入非工作状态。 第一跨阻放大器和第二跨阻抗放大器共享输入晶体管。 第一跨阻放大器具有设置在其反馈节点和连接到输入晶体管的输入节点之间的第一电阻器。 第二跨阻放大器具有设置在其反馈节点和第一电阻器之间的第二电阻器。 第二跨阻放大器的反馈电阻器通过串联连接第一电阻器和第二电阻器而构成。 版权所有(C)2012,JPO&INPIT