Active filter circuit with resistors and capacitors - has current differential amplifier and consists of four-terminal network

摘要

The filter circuit consists of resistors, capacitors and a current differential amplifier (Norton operational amplifier). It is in the form of a four-terminal network, with one input terminal directly connected to an output terminal. Filter input (7) is connected through a resistor (R4) to the amplifier (3) non-inverting input (4) and through a resistor (R3) to a first junction point (1). This junction point (1) is connected through a capacitor (C1), a second junction point (2) and a resistor (R1) to the amplifier (3) inverting input (5). Amplifier (3) output (9) which is also the filter output, is connected through a resistor (R6) to its non-inverting input (4), through a capacitor (C2) to the first junction point (1) and through a resistor (R2) to the second junction point (2). The first junction point (1) is connected through a resistor (R5) to the through wire (10).