Dual Output Voltage Differencing Buffered Amplifier Based Active -C Multiphase Sinusoidal Oscillator

Abstract

A multiphase sinusoidal oscillator (MSO) using dual output voltage differencing buffered amplifier (DO-VDBA) is presented in this paper which provides n equally spaced phase sinusoids of equal magnitudes. The proposed MSO topology is realized using the first order all pass network (APN). In the proposed structure the output voltages are made available at low impedance nodes which makes the proposed MSO easy for cascadability. Making the proposed structure a resistorless structure is a major challenge. The main benefits of the structure are easy integration and less power losses. The formulation of frequency and condition of oscillation is derived mathematically. The oscillation frequency can be tuned electronically, is an added advantage of the proposed MSO. The effect of device non-idealities is also discussed in the study. To assess the proposed MSO performance further Monte Carlo analysis was carried out. The workability of the proposed structure is verified through SPICE simulations for a three (n=3) and four (n=4) phases MSO, and the obtained simulated results are in close agreement with the theoretical values. The total harmonic distortion (THD) is found to be quite low.