Identification of a class of two CFOA-based sinusoidal RC oscillators

Using a unified representation for a class of the two current-feedback operational amplifier (CFOA) sinusoidal oscillators, new circuits of this type can be systematically discovered. A catalogue of two circuit structures, each structure realizing 18 oscillator circuits, is presented. Moreover, using the RC:CR transformation, additional 18 oscillator circuits can be obtained from each structure. A third structure realizing additional two oscillator circuits is also presented. Some of the circuits enjoy one or more of the following attractive features: use of grounded capacitors, feasibility of absorbing the parasitic components of the CFOAs, availability of a buffered output voltage and orthogonal tuning of the frequency and the startup condition of oscillation. Moreover, it is shown that the use of the Barkhausen criterion for the determination of the startup condition of oscillation and the frequency of oscillation yields inaccurate results with relatively large errors depending on the selected component values. Furthermore, it is shown that using the roots of the characteristic equation of a specific oscillator structure will result in a startup condition that cannot be adjusted without disturbing the frequency of oscillation.

[1]  Muhammad Taher Abuelma'atti,et al.  Two new minimum-component Wien-bridge oscillators using current-conveyors , 1987 .

[2]  Vimal Singh.  Failure of Barkhausen oscillation building up criterion: Further evidence , 2007 .

[3]  Vinod Kumar Singh,et al.  Novel single-resistance-controlled-oscillator configuration using current feedback amplifiers , 1996 .

[4]  K. K. Clarke,et al.  Communication Circuits: Analysis and Design , 1971 .

[5]  S. Webb,et al.  Applications of a commercially available current conveyor , 1991 .

[6]  Raj Senani,et al.  New voltage controlled oscillators using CFOAs , 2009 .

[7]  Worapong Tangsrirat,et al.  Single-resistance-controlled quadrature oscillator and universal biquad filter using CFOAs , 2009 .

[8]  Chun-Yueh Huang,et al.  Comment: A note on determination of oscillation startup condition , 2007 .

[9]  S. S. Gupta,et al.  State variable synthesis of single-resistance-controlled grounded capacitor oscillators using only two CFOAs: additional new realisations , 1998 .

[10]  Vimal Singh,et al.  Discussion on Barkhausen and Nyquist stability criteria , 2010 .

[11]  T. Pukkalanun,et al.  CFOA-based single resistance controlled quadrature oscillator , 2008, 2008 SICE Annual Conference.

[12]  M. Jézéquel,et al.  Discussion on the general oscillation startup condition and the Barkhausen criterion , 2009 .

[13]  Anwar A. Khan,et al.  Novel RC sinusoidal oscillator using second-generation current conveyor , 2005, IEEE Transactions on Instrumentation and Measurement.

[14]  Muhammad Taher Abuelma'atti,et al.  Novel CFOA-based sinusoidal oscillators , 1997 .

[15]  Ahmed M. Soliman.  Current Feedback Operational Amplifier Based Oscillators , 2000 .

[16]  Raj Senani,et al.  Synthesis of single-resistance-controlled oscillators using CFOAs: simple state-variable approach , 1997 .

[17]  Raj Senani,et al.  New CFOA-Based Single-Element-Controlled Sinusoidal Oscillators , 2006, IEEE Transactions on Instrumentation and Measurement.

[18]  Raj Senani,et al.  State variable synthesis of single resistance controlled grounded capacitor oscillators using only two CFOAs , 1998 .

[19]  C. Aldea,et al.  Grounded resistor controlled sinusoidal oscillator using CFOAs , 1997 .

[20]  Bernabé Linares-Barranco,et al.  On the design of voltage-controlled sinusoidal oscillators using OTAs , 1990 .

[21]  Vimal Singh.  A note on determination of oscillation startup condition , 2006 .

[22]  Ahmed M. Soliman.  Transformation of oscillators using Op Amps, unity gain cells and CFOA , 2010 .