Design of the simple oscillator with linear tuning and pi/4 phase shift based on emulator of the modified current differencing unit

Abstract

This paper presents a simple oscillator with 45 degrees phase shift between output signals. A Modified Current Differencing Unit (MCDU) was used for its design. The MCDU offers controllability of input resistances of current inputs and controllability of current gains. These features are not available together in the standard current differencing unit and it limits usability in some applications. The proposed oscillator allows linear electronic control of oscillation frequency and independent control of condition of oscillation with simple implementation of amplitude stabilization. The PSpice simulations and measurements in laboratory with manufactured behavioral emulator of the MCDU confirmed the expected features of the solution.