| 摘要 |
An active filter having a predetermined fourth-order transfer function is realized by employing a single gain unit, for example, a differential amplifier, in conjunction with two passive resistor-capacitor (RC) circuits. The RC circuits have pole-zero pairs which are widely separated in frequency. Consequently, each RC circuit does not cause appreciable distortion in the attenuation characteristic of the filter in the frequency band in which the other RC circuit is affecting the filter attenuation characteristic. |
