Importance of amplitude stability and spectral purity of produced signals in a quadrature oscillator

This paper presents two solutions for an amplitude automatic gain control circuit implemented in a simple second-order quadrature oscillator based on the non-inverting band-pass filtering response and a block with positive feedback with controllable gain or intentional nonlinearity. The results regarding amplitude stability, total harmonic distortion, available tunability range, time required to obtain stable oscillations, etc. are discussed and both AGC solutions are compared. PSpice software was used for verification in simulations.

[1]  Dalibor Biolek,et al.  Current-Mode CCII+ Based Oscillator Circuits using a Conventional and a Modified Wien-Bridge with All Capacitors Grounded , 2011 .

[2]  Dalibor Biolek,et al.  Low-distortion current-mode quadrature oscillator for low-voltage low-power applications with non-linear non-inertial automatic gain control , 2011, 2011 20th European Conference on Circuit Theory and Design (ECCTD).

[3]  Jan Jerabek,et al.  Tunable Multiphase Oscillator Using Diamond Transistors with Voltage Controlled Condition of Oscillation for Amplitude Stabilization , 2014 .

[4]  Jan Jerabek,et al.  Precise Electronically Adjustable Oscillator Suitable for Quadrature Signal Generation Employing Active Elements with Current and Voltage Gain Control , 2014, Circuits Syst. Signal Process..

[5]  Maneesha Gupta,et al.  A transconductance boosted CMOS current differencing transconductance amplifier (TBCDTA) and its application , 2015 .

[6]  Viera BIOLKOVÁ,et al.  Four-Phase Oscillators Employing Two Active Elements , 2011 .

[7]  Z. Hrubos,et al.  Study of Adjustable Gains for Control of Oscillation Frequency and Oscillation Condition in 3R-2C Oscillator , 2012 .

[10]  Roman Sotner,et al.  New Compact VM Four-Phase Oscillator Employing Only Single Z-Copy VDTA and All Grounded Passive Elements , 2013 .

[11]  Montree Siripruchyanun,et al.  Realization of electronically tunable voltage-mode/current-mode quadrature sinusoidal oscillator using ZC-CG-CDBA , 2011, Microelectron. J..

[12]  C. SAKUL,et al.  New Resistorless Current-Mode Quadrature Oscillators Using 2 CCCDTAs and Grounded Capacitors , 2011 .