VOLTAGE DIFFERENCING CURRENT CONVEYOR (VDCC) AND ITS APPLICATIONS

Abstract

Precisely tailored frequency filters can be produced with standard operational amplifiers however for audio application only. In higher frequency range, use of some of modern active functional blocks is preferred. Recently, various active building blocks have been presented in which versatile and powerful building blocks are the Voltage Differencing Current Conveyor (VDCC). Active filters based on the VDCC have recently found attractive considerable attention. This stems from inherent incognito advantages of the current conveyor circuits and OTA circuits, namely low supply voltages and power, current operational mode possibility, well-developed IC topology and particularly a frequency range of the signal processing which can be higher than with circuits with the standard operational amplifiers. Since their introduction, the VDCC have led to a great number of applications in signal processing circuits, especially many oscillators and filters. Tow Thomas Biquad based on VDCC is a new voltage mode biquad circuit. This circuit uses two voltage differencing current conveyors (VDCC) along with five resistors and two capacitors as passive elements. KHN Biquad filter using VDCC is a current mode universal biquad filter using voltage differencing current conveyor (VDCC). This filter circuit uses all grounded passive elements. The pole frequency (􀫑o) and quality factor (Q) can be tuned independently in the presented filter structure. In VDCC Based TISO (three input single output) and SIDO (single input dual output) Biquad Filter, three voltage mode biquad structure is analysed. The first structure is three input single output biquad structure and the other two structures are single input dual output biquad structures whose quality factor can be adjusted by adjusting one resistor without changing pole frequency. Pole frequency of all the filters can be electronically tuned by varying biasing current. VDCC based Inductance Simulator is an actively simulated grounded inductor. It has been used in innumerable applications beginning from filter to oscillator design as well as cancellation of parasitic inductances. Moreover, new grounded inductance simulators using only one voltage differencing current conveyor (VDCC) and two passive elements are presented. This inductance simulators can be tuned electronically by changing the biasing current of the VDCC. These circuits do not require any component matching conditions. VDCC based floating inductance simulator is also presented. Using grounded inductance simulator, a thirdorder high-pass filter is constructed. Fifth order Low-Pass and High-Pass Ladder Filters based on VDCC are presented which employs two Voltage Differencing Current Conveyors (VDCCs), four resistors and five capacitors. The workability of all the filters has been verified using PSPICE simulations.