【摘要】 介绍了一种基于蛙跳式低通滤波器原型综合而成的复数滤波器。该电路具有较低的灵敏度,从而提高了稳定性。滤波器的自动调谐系统具有设计简单、精度易控制等特点,并可在调谐完成后关闭,减少了功耗以及与滤波器的互扰。电路采用0.18μm CMOS工艺设计,滤波器的中心频率为4 MHz,带宽为2 MHz,增益约为0 dB,可达到约53 dB的镜像抑制比,调谐精度可以控制在3%左右,功耗为7.5 mW。更多还原

【Abstract】 A complex filter synthesized from the leapfrog lowpass prototype is proposed.The filter has low (sensitivity) and,therefore,an improved stability.The tuning system,which is easy to design and well controlled,can be turned off on the completion of tuning,which reduces power consumption and interference with the filter.Implemented in 0.18 μm CMOS process,the filter is centered at 4 MHz with a bandwidth of 2 MHz and a voltage gain of about 0 dB.The image rejection ratio of the filter is up to 53 dB and its tuning accuracy is about 3%.The device consumes 7.5 mW of power.更多还原