A novel voltage-mode universal filter composed of two terminal active devices

A novel voltage-mode (VM) universal filter is proposed in this work. A voltage follower (VF) and a negative impedance converter (NIC) which are two terminal active elements are used in the implementation of the proposed filter. Also, two capacitors and three resistors are employed in the proposed filter as passive circuit elements. On the other hand, each of the VF and NIC can be easily constructed by using a plus-type second-generation current conveyor. One of the main advantages of the proposed filter is the feature of low output impedance resulting in easy cascadability with other VM circuits. Moreover, the quality factor of the proposed filter can be easily adjusted by changing value of only one of the resistors without disturbing its angular resonance frequency. Nonetheless, it requires a single resistive matching condition for proper circuit operation and a unity gain inverting amplifier for only all-pass filter responses. A number of simulation results are achieved by using 0.13 μm IBM CMOS technology parameters with ±0.75 V DC power supply voltages. Power consumption of the proposed filter is approximately found as 3.65 mW through SPICE simulations. Furthermore, experimental test results are included to confirm the theory.