Electronically linearly voltage controlled second-order harmonic oscillator with multiples of π/4 phase shifts

Simple multiphase second-order oscillator based on special active device, so-called Z-copy Voltage Controlled Current Follower Differential Input Transconductance Amplifier (ZC-VCCFDITA) is present in this contribution. Simple linear control of oscillation frequency by DC voltage is easily possible. Simple automatic gain control circuit (AGC) for amplitude stabilization is also presented. Three output signals have phase difference (multiples of π/4) and amplitude of produced signal is not disturbed by the tuning process. Functionality of proposed application is verified by Spice simulations of newly proposed behavioral model based on commercially available devices that predetermines initial practical features of active element for future design or fabrication.