CCCIIs-Based First-Order All-Pass Filter and Quadrature Oscillators

Abstract

This paper introduces a current-mode first-order all-pass filter (APF) and its application in quadrature oscillator (QO) based on CCCII. The proposed filter can provide inverting and noninverting all-pass functions with a same circuit topology, it uses two CCCIIs and one grounded capacitor. Moreover, the first-order all-pass filter was applied in current-mode sinusoidal quadrature oscillators with the design based on block diagrams. The introduced oscillators can provide four phase-quadrature signals which independently control the condition of oscillation (CO) and frequency of oscillation (FO). The proposed oscillators consist of three CCCIIs and two grounded capacitors. The proposed APF and QOs have high output impedance which can directly drive load without additional current buffer. In addition, they use only grounded capacitors which are very appropriate to future development into an integrated circuit. The results of PSPICE simulation program correspond to the theoretical analysis.

The development of a fully balanced current-tunable active-RC all-pass filter

“…Equation (11) shows the transfer function of phase-lag all-pass filter. The corner frequency form of this filter has the following form (12):…”

“…This circuit has been extensively studied and documented in international journals over the past decade, with notable contributions from various researchers [7][8][9][10]. Additionally, specific work by [11][12][13] has focused on designing an all-pass filter tailored for configuring the frequency of a sinusoidal quadrature circuit. Researchers have explored a wide range of configurations for all-pass filter structures, including those incorporating active components, which offer distinct advantages Engineering over passive device synthesizer circuits.…”