Generation of Four Phase Oscillators Using Op Amps or Current Conveyors
Ahmed M Soliman and Chun Ming Chang
A novel four phase oscillator circuit using two balanced output Op Amps is given. The circuit considered is generated from a two integrator loop oscillator circuit which uses three single input Op Amps and employs the minimum number of capacitors namely two. An equivalent current conveyor circuit which employs grounded resistors and capacitors is obtained from the three Op Amp circuit by equivalent block replacement. Another equivalent unity gain cells four phase oscillator realizing the same characteristic equation and using two grounded capacitors is also given. Nodal Admittance Matrix (NAM) expansion is used to generate the family of current conveyor four phase oscillators. Spice Simulation results are given.
Keywords: Four-phase oscillators, Balanced output Op Amp, unity gain cells, current conveyor.