Active filters fourth-order lowpass with zero TRANSMISSION

摘要

Active low-pass filter of the fourth order frequency with a transmission zero, comprising serially connected filter input terminal, first, second, third and fourth resistors, the first and the second amplifiers, the output of the latter is the filter output, the second terminals of the first, second, third and fourth resistors connected to the first terminals, respectively, first, second, third and fourth capacitors, the second terminals of the first and third capacitors are connected to the output of the first amplifier, the second terminals of the fourth - fifth through resistor with the output of the first amplifier and via a fifth capacitor filter output which, via a sixth resistor connected to the common point of the first, second resistor and first capacitor, via the sixth capacitor - to the common point of the second, third resistor and a second capacitor, wherein the second terminal a second capacitor connected to the common switching point of the fourth, fifth and fifth capacitors resistor.