A new analogue sampled-data active device, called as a switched-current operational amplifier (SIOA), is presented. The use of the active element may simplify drawing the circuit diagram greatly and may permit easier analysis and synthesis of SI networks. A number of all pole and elliptic (second or third order) switched current (SI) circuits are derived from the switched capacitor prototypes. These can be used as simple self-contained filters or as filter sections in the cascade realizations of a higher order transfer functions. To illustrate the design approach, a fifth-order lowpass filter is presented.