Low Input Impedance Mixed-mode Single Input Four Outputs Universal Filter Using Three FTFNs and Grounded Capacitors
Syed Zaffer Iqbal, Nusrat Perveen and Munazah Quadri
A novel filter topology using three FTFNs three virtually grounded resistors and two grounded capacitors providing four outputs is proposed. The circuit operates in transimpdance mode (TI) and current-mode (CM) when the input signal is current. The circuit provides simultaneously three voltage outputs and a single current output. The circuit exhibits low input impedance which is highly suitable for cascading without using buffers. The circuit can be converted into voltage-mode (VM) and transadmittance-mode (TA) by simply placing resistor at input. The use of grounded capacitors is suitable for IC implementation and also all the resistors are virtually grounded. The circuit enjoys orthogonal tuning of band width, and pole frequency. The sensitively figures are equal to or less than unity. PSPICE simulation results the confirm the workability of the proposed filter.
Keyword: Continuous time filters, Low input impedance, transadmittance filter, FTFNs.