DESIGNING OF BIQUAD FILTER USING VDCC

It is widely accepted that all filters can be fabricated with the help of standard operational amplifiers. It is mainly used for audio application. For the creation of higher frequency ranges modern active functional blocks have been used. Recently, various kind of functional building blocks have been implemented, out of them only versatile and functional building blocks are useful for voltage differencing current conveyor (VDCC). VDCC based continuous time active RC filters have gained more attention in recent time.  This branch of electronics having some useful advantages of the current conveyor filters and OTA filters, which is named as low supply voltages and power. Standard amplifiers are able to provide well developed IC topology and specific frequency ranges for signal processing. Since their inception, the VDCC have guided multiple of applications in signal processing circuits, for the development of many oscillators and filters. Sedra and Smith in 1968, first time introduced the principal of the current conveyor of first generation. After that multiple applications of current conveyors have been published by other people. After putting so much of efforts on research, current conveyors are still not available in the form of IC and, because of this reason this active block not being used in many analog circuit and system design applications by many developers. Some op-amps based applications on current conveyors are available, which can provide high speed and wide band, in the form of integrated circuits such as AD844, OPA660, and AD844. Analog VLSI can deal with nearly all real world issues and has extended its range of circuits (amplifier, filters, communication circuits, current comparators etc) for new information processing applications in numerous fields like integrated sensors, image processing, speech recognition, hand writing recognition etc.This lead to an increased interest in the evolution process of active elements which are used for analog signal processing.