开关电流电路中的时钟馈入效应

Clock Feedthrough Effects in Switched-Current Circuits

本文采用ＭＯＳ开关的集总时变ＲＣ模型，对开关电流（ＳＩ）电路中的时钟馈入效应进行了详细的理论分析，导出了开关电流镜中钟馈电压和钟馈电流的表达式，从而揭示出了钟馈电压／电流与工艺参数、ＭＯＳ器件尺寸、时钟信号幅值及其下降沿斜率等之间的内在关系。用它可对ＳＩ电路中时钟馈入的影响进行快速预测。文中的理论分析与ＳＰＩＣＥ仿真结果相一致。所提供的结果对于设计高精度低功耗ＳＩ电路有应用价值。

A careful study is made about the clock feedthrough effects in switched-current(SI)circuits by using a lumped time variant RC model for MOS switches. Expressions for clock feedthrough voltage and cur- rent in SI mirrors are derived,which describe the interdependence of the clock feedthrough voltage/current on the process parameters.MOS device sizes.clock signal magnitude and its falling edge slopes.Using these ex- pressions,effects of clock feedthrough in SI circuits can be predicted very quickly.The theoretical analysis in the work agrees with results from SPICE simulation.