High Output Impedance Current-Mode Universal First-Order Filter With Three Inputs Using One DDCC

Background: A current-mode universal first-order filter with three input terminals and one output terminal is presented. Methods: The proposed circuit uses one differential difference current conveyor (DDCC), one grounded capacitor and two resistors. Results: This circuit offers the following advantageous features: high output impedance, employing only one active component, using a grounded capacitor, the versatility to synthesize any type of first-order filter transfer functions. Conclusion: Each standard first-order filter function can be obtained by using only one current input signal from the proposed circuit.