Quadrature oscillators using CCIIs

Abstract

Three third-order quadrature oscillators are proposed. Outputs of two sinusoids with 90 phase difference are available in each quadrature oscillator circuit. The oscillation condition and oscillation frequency of each proposed quadrature oscillator are orthogonal controllable. All proposed circuits employ only grounded capacitors. The use of only grounded capacitors is ideal for integration. Experimental results are included to confirm the theoretical analysis.

New Realization of Quadrature Oscillator using OTRA

“…This has led a consistent research effort towards second order QO design using wide variety of active blocks, as is evident from vast literature available [2][3][4][5][6][7][8][9][10][11][12][13][14] .It is well known that higher order networks, provide better accuracy, frequency response and distortion performance [15][16][17] as compared to lower order circuits. Owing to this in recent past few third order QO designs [15], [16], [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] have been reported. Realizing sinusoidal oscillator using closed loop with positive feedback is a well-established method.…”

“…Lack electronic tunability [15], [19], [20], [24] b. Use mix of active blocks such as DDCC and OTA [28],CCCDTA and OTA [29],CCCCTA and OTA [30] [15], [16], [20], [22], [24], [25], [28], [29], [31] making a buffer necessary to drive the voltage input circuits d. Provide current output [18], [20][21][22]which need to be converted to voltage for circuits requiring voltage inputs and would considerably increase the component count Above discussion suggests that OTRA based QO is most suitable choice for voltage output configurations.Rest of the paper is as organized as follows: in section 2 proposed circuit is described followed by Effect of nonideality of OTRA is dealt in section 3. Section 4 explains the MOS-C implementation details of proposed structure.…”

“…Additionally these circuits use more number of active components as compared to proposed circuit a. Lack electronic tunability [15], [19], [20], [24] b. Use mix of active blocks such as DDCC and OTA [28],CCCDTA and OTA [29],CCCCTA and OTA [30] …”

New voltage-mode universal filter and sinusoidal oscillator using only single DBTA

“…The analogue frequency filters are the most often used as anti-aliasing video filters in the analogue sections of high-speed data communication systems defined by ITU BT 601 standard (Uygur and Kuntman 2007) or for signal processing in wireless LANs described by IEEE 802.11 standard (Lo et al 2009), in IF (intermediate frequency) receiver stages of the GSM cellular telephones (Fabre et al 1997, Ibrahim et al 2005, in receiver baseband blocks of modern radio systems (Rudell et al 1997, in hard-drive communication interfaces (Laber and Gray 1993), measurement systems (Vainio and Ovaska 1997), automotive industry (Ferri and Guerrini 2003), or in piezoresistive pressure sensors (Samitier et al 1998). Oscillators also represent an important unit in many telecommunication, instrumentation and control systems (Holzel 1993, Ahmed et al 1997, Cam et al 1998, Cicekoglu and Toker 1999, Soliman 1999 Horng et al 2005).…”

Mixed-Mode Third-Order Quadrature Oscillator Based on Single MCCFTA

“…The early system using operational transconductance amplifier (OTA) [30] enjoys electronic tuning capability, but its CO and FO are not decoupled and difficult to control. The QOs using active building blocks such as operational amplifier [31], second-generation current conveyor (CCII) [32][33][34], differential voltage current conveyor (DVCC) [35], operational transresistance amplifier (OTRA) [36], [37], [50], offer orthogonal control of CO and FO, but these structures lack the electronic tuning capability. A number of electronic-controlled third-order QOs have been reported using active building blocks such as current-controlled CCII (CCCII) [38], [39], current difference transconductance amplifier (CDTA) [40], [41], current-controlled CDTA (CCDTA) [42], current-controlled current conveyor transconductance amplifier (CCCTA) [43], [44], OTRA and MOS-C [45], DDCC and VDTA [46], [51], [52], differential voltage current conveyor transconductance amplifier (DVCCTA) [47].…”