提出了一种新的开关电感有源滤波器电路形式,该电路由运算放大器和电子开关切换接入的电感组成,并从时域和频域两个方面对其频谱特性进行了深入分析,结果表明:电子开关切换频率较高时,电路是一个梳状滤波器,通带中心频率为开关切换频率的奇数倍,开关频率的偶数倍则为其阻带中心频率.随着开关切换频率降低,电路过渡为幅频特性有起伏的高通滤波器.
A novel comb switched-inductance active filter is designed. The circuit is composed of operational amplifier and electronics switched-inductance. Its spectrum characteristic is analyzed in time-domain and frequency domain. As a result, electronic switching frequency fT is higher,this circuit is a comb filter,and the passband center frequency is equal to the odd times of switching frequency fT,and the band elimination frequency is equal to the even times of fT. With the fT lower, this circuit changes into a high-pass filter