Switched-capacitor frequency-to-current converter
    2.
    发明授权
    Switched-capacitor frequency-to-current converter 有权
    开关电容器频率到电流转换器

    公开(公告)号:US06798372B1

    公开(公告)日:2004-09-28

    申请号:US10405191

    申请日:2003-04-01

    IPC分类号: H03M160

    CPC分类号: H03D13/003 H03K9/06

    摘要: A frequency-to-current converter operative to convert a clock frequency to an output current is described; the frequency-to-current converter ensures that the output current increases linearly with the clock frequency. The frequency-to-current converter may be incorporated in analog-to-digital converters driven by clocks with variable frequencies. The frequency-to-current converter employs an integrator circuit, used to compare an input reference voltage and a current feedback into a sampling capacitor. At steady state, the feedback current is just sufficient to discharge the sampling capacitor to a fixed voltage. The core of the frequency-to-current conversion circuit includes one opamp, two capacitors, one feedback transistor and a few switches.

    摘要翻译: 描述了将时钟频率转换为输出电流的频率到电流转换器; 频率到电流转换器确保输出电流随时钟频率线性增加。 频率到电流转换器可以并入由具有可变频率的时钟驱动的模数转换器中。 频率到电流转换器采用积分器电路,用于将输入参考电压和电流反馈比较到采样电容器中。 在稳定状态下,反馈电流恰好足以将采样电容放电到固定电压。 频率到电流转换电路的核心包括一个运算放大器,两个电容器,一个反馈晶体管和几个开关。

    Apparatus and methods for safe-mode delta-sigma modulators
    4.
    发明授权
    Apparatus and methods for safe-mode delta-sigma modulators 有权
    安全模式delta-sigma调制器的装置和方法

    公开(公告)号:US07701372B1

    公开(公告)日:2010-04-20

    申请号:US12145965

    申请日:2008-06-25

    IPC分类号: H03M3/00

    CPC分类号: H03M3/44 H03M3/424 H03M3/454

    摘要: A delta-sigma modulator includes two integrators. One of the two integrators is lossy. The lossy integrator may be a continuous-time integrator, or a discrete-time integrator. Use of the lossy integrator maintains stability of the delta-sigma converter over a relatively wide range of input signals.

    摘要翻译: Δ-Σ调制器包括两个积分器。 两个集成商之一是有损的。 有损积分器可以是连续时间积分器或离散时间积分器。 使用有损积分器可在相对宽的输入信号范围内维持delta-sigma转换器的稳定性。