Active filter
OwnerRoberto Cavazzoniinventor
Life of this patent
Estimating the term…
Abstract
An active filter comprising a first operational amplifier (10) disposed in an inverting integral configuration through a feedback capacitor (14) and a main resistor (15), and a divider (20) connected through a first connecting terminal (22) thereof with a noninverting input (12) of the first operational amplifier (10). In a second embodiment filter 1 comprises a main operational amplifier (100) disposed in an inverting integral configuration through a capacitor (101) and a resistor (102), and a secondary operational amplifier (110) fed back through feedback means (120) and connected with the main operational amplifier (100) through a resistor (130). An inverting input (110a) of the secondary operational amplifier (110) is connected with a noninverting input (100b) of the main operational amplifier (100).
Claims26
1-36. (canceled)
An active filter comprising:
- a main operational amplifier (100) having an inverting input (100a), a noninverting input (100b) and an output (100c);
- a capacitor (101) having one end (101a) connected with the output (110c) of said main operational amplifier (100), and a second end (101b) connected with the inverting input (100a) of said main operational amplifier (100);
- a resistor (102) having one end (102a) connected with the inverting input (100a) of said main operational amplifier (100), and a second end (102b);
- a secondary operational amplifier (110) having an inverting input (110a), a noninverting input (110b) and an output (110c);
- feedback means (120) connected between the output (110c) of said secondary operational amplifier (110) and the inverting input (110a) of said secondary operational amplifier (110);
- a resistor (130) having one end (130a) connected with the inverting input (110a) of said secondary operational amplifier (110) and a second end (130b) connected with the output (100c) of said main operational amplifier (100), characterised in that the noninverting input (100b) of said main operational amplifier (100) is connected with the inverting input (110a) of said secondary operational amplifier (110), preferably through a direct connection (230).
Dependencies are inferred from the claim text.