REJECTOR FILTER OF THE SALLEN-KEY FAMILY BASED ON A MULTI-DIFFERENTIAL OPERATIONAL AMPLIFIER Russian patent published in 2022 - IPC H03H11/12 

FIELD: radio engineering.

SUBSTANCE: invention relates to the field of radio engineering and can be used, for example, to filter signals in radio monitoring systems or to suppress interference in communication lines with sensors and in integrated circuit power buses. The notch filter of the Sallen-Key family based on a multi-differential operational amplifier contains an input (1) and an output (2), a multi-differential operational amplifier (3) with non-inverting (4) and inverting (5) inputs of the first input port, as well as with non-inverting (6) and inverting (7) inputs of the second input port, the first (8) and second (9) frequency setting resistors, the first (10) and second (11) frequency setting capacitors. The output of the amplifier (3) is connected to the output (2). The notch filter also contains the first (13) and second (14) additional frequency-setting resistors, as well as the first (15) and second (16) additional frequency-setting capacitors, and the input (1) is connected to the non-inverting (4) input of the first input port of the amplifier ( 3) through the first (8) and second (9) frequency-setting resistors connected in series, the common node of which is connected to the output (2) through the first (10) frequency-setting capacitor, the input (1) is connected to the non-inverting (6) input of the second input port of the amplifier ( 3) through the first (15) and second (16) additional frequency-setting capacitors connected in series, the common node of which is connected to the output (2) and the inverting (7) input of the second input port of the multidifferential operational amplifier (3) through the first (13) additional frequency-setting resistor , inverting (5) input of the first input port of the amplifier (3) is matched with a common power supply bus (12), non-inverting input (4) of the first input port amplifier (3) is connected to a common power supply bus (12) through the second (11) frequency-setting capacitor, non-inverting (6) input of the second input port of the amplifier (3) is connected to a common power supply bus (12) through the second (14) additional frequency-setting resistor .

EFFECT: creation of conditions under which a Sallen-Key notch filter with low current consumption is implemented based on a single multi-differential operational amplifier.

1 cl, 5 dwg