13th International Conference on Microelectronics (ICM 2001), Rabat, Malta, 29 - 31 October 2001, pp.149-152
This paper describes a current-mode third-order Butterworth filter realised with unity gain active elements and minimum number of passive components. All capacitors and resistors are equal valued. The core of the circuit realises HP, BP and LP functions easily. The filter exhibits high output impedance. Experimental results are included to verify theory.