设计了一种应用于直接变频接收机的低功耗混合信号直流失调消除(DCOC)电路。该电路采用混合信号的方式消除直流失调电压,避免了传统模拟域直流失调消除系统环路响应速度与高通带宽之间的折中,具有功耗低、建立时间快、面积小等优点。采用该DCOC后,直接变频接收机的输出剩余直流失调电压小于37mV,直流失调消除环路的建立时间小于200μs。电路采用0.13μm CMOS工艺实现,芯片尺寸为0.372mm×0.419mm,工作于1.2V电源电压时,消耗电流仅为196μA。 A low power consumption DC / DC offset cancellation (DCOC) circuit for direct conversion receiver is designed. The circuit adopts the mixed signal to eliminate the DC offset voltage and avoids the compromise between the loop response speed and the high pass bandwidth of the conventional DC offset cancellation system. The circuit has the advantages of low power consumption, fast setup time and small area. With this DCOC, the DC offset of the output of the direct conversion receiver is less than 37mV and the settling time of the DC offset cancellation loop is less than 200μs. The circuit is implemented in a 0.13μm CMOS process with a chip size of 0.372mm × 0.419mm, consuming only 196μA when operating at 1.2V supply voltage.