Resistorless dual-mode quadrature sinusoidal oscillator using a single active building block

This paper presents a new realization of resistorless mixed-mode (i.e. both voltage-mode and current-mode) quadrature sinusoidal oscillator using a new active building block (ABB) called the differential voltage current-controlled conveyor transconductance amplifier (DVCCCTA). The proposed oscillator circuit uses a single DVCCCTA, two grounded capacitors (GCs) and does not employ any external linear resistors. The tuning laws for the condition of oscillation (CO) and the frequency of oscillation (FO) are non-interactive; and controlled by separate bias currents. The circuit provides two explicit quadrature current outputs and two quadrature voltage outputs and thus can be classified as a mixed-mode quadrature oscillator. Another notable feature of the proposed circuit is that it can also be used as a biquadratic filter to realize low-pass and band-pass filtering functions simultaneously. Non-ideal analysis of the circuit is provided and PSpice simulation results have been included to verify the workability of the proposed circuit.     

Quadrature Oscillators with Grounded Capacitors and Resistors Using FDCCIIs

Two current‐mode and/or voltage‐mode quadrature oscillator circuits each using one fully‐differential second‐generation current conveyor (FDCCII), two grounded capacitors, and two (or three) grounded resistors are presented. In the proposed circuits, the current‐mode quadrature signals have the advantage of high‐output impedance. The oscillation conditions and oscillation frequencies are orthogonally (or independently) controllable. The current‐mode and voltage‐mode quadrature signals can be simultaneously obtained from the second proposed circuit. The use of only grounded capacitors and resistors makes the proposed circuits ideal for integrated circuit implementation. Simulation results are also included.     

New canonic lossy inductor using a single CDBA and its application

A new lossy inductor (parallel R-L type) using single current differencing buffered amplifier (CDBA) is presented, which employs only two resistors and a grounded capacitor. The proposed lossy inductor is shown to be useful in realizing an oscillator circuit, which provides quadrature voltage outputs using only two CDBAs, three resistors and two grounded capacitors and offers independent control on condition of oscillation and frequency of oscillation up to a frequency of 61 MHz. Detailed non-ideal analysis including single-pole model for voltage and current gain has also been carried out. SPICE simulation results and experimental results based upon the CDBA constructed from commercially available IC AD844 have been included which confirm the practical workability of the proposed lossy inductor and quadrature oscillator circuit.     

Realization of electronically tunable voltage-mode/current-mode quadrature sinusoidal oscillator using ZC-CG-CDBA

This paper presents a first of its kind canonic realization of active RC (ARC) sinusoidal oscillator with non-interactive/independent tuning laws, which simultaneously provides buffered quadrature voltage outputs and explicit quadrature current outputs. The proposed circuit is created using a new active building block, namely the Z-copy controlled-gain current differencing buffered amplifier (ZC-CG-CDBA). The circuit uses three resistors and two grounded capacitors, and provides independent/non-interactive control of the condition of oscillation (CO) and the frequency of oscillation (FO) by means of different resistors. Other advantageous features of the circuit are the inherent electronic tunability of the FO via controlling current gains of the active elements and the suitability to be employed as a low-frequency oscillator. A non-ideal analysis of the circuit is carried out and experimental results verifying the workability of the proposed circuit are included.     

Current‐mode quadrature oscillator using current differencing transconductance amplifiers

This article presents a new electronically tunable single‐element‐controlled current‐mode quadrature sinusoidal oscillator circuit using current differencing transconductance amplifiers (CDTAs). The proposed oscillator is consisted of two CDTAs, two grounded capacitors and one grounded resistor, which is beneficial to monolithic integrated circuit implementation both in CMOS and bipolar technologies. The condition of oscillation and the frequency of oscillation are independently controllable. The frequency of oscillation can also be electronically controlled by adjusting the bias current of CDTA. The circuit provides four quadrature current outputs and two quadrature voltage outputs. The current output terminals possess high impedance level. PSPICE simulation results are used to verify the performance of the proposed circuit implemented at the transistor level. The measurement results support the computer simulations.     

Cyclostationarity-based model for noise analysis of charge amplification with correlated double sampling

A lossless floating inductance has been simulated using two differential voltage current conveyors, two resistors and one grounded capacitor. The proposed floating inductance needs not component matching condition. Base on the proposed floating inductance as building block, a new voltage-mode universal biquadratic filter with one input and five outputs can be obtained. The proposed universal biquad uses two differential voltage current conveyors, three resistors and two grounded capacitors. All standard filter functions; highpass, bandpass, lowpass, notch and allpass can be obtained, simultaneously, without changing the passive elements. The proposed universal biquad has the features of using only grounded capacitors and orthogonal controllable of resonance angular frequency and quality factor.     

单片CDCTA-C低功耗电控调谐双模式三阶正交振荡器的设计

针对振荡器功耗大和振荡频率低的问题,提出了一种基于电流差分级联跨导放大器的三阶正交振荡电路.该电路仅使用一个电流差分级联跨导放大器和三个接地无源电容,可以同时产生两组等幅正交电流信号和一组等幅正交电压信号.电路结构简单,功耗低至1.8mW,最大灵敏度绝对值仅0.5,振荡频率可达10MHz数量级,而且振荡条件和震荡频率可相互独立地电控调谐.计算机模拟和流片芯片测试结果验证了理论分析的正确性.     

Single-resistance-controlled quadrature oscillator using current differencing buffered amplifiers

A single-resistance-controlled quadrature oscillator circuit using current differencing buffered amplifiers (CDBAs) as active components is proposed. The proposed circuit is realised through the employment of two CDBAs, three resistors and two grounded capacitors. Outputs of two sinusoidal with 90° phase difference are available. The oscillation condition and the oscillation frequency of the proposed quadrature oscillator can be controlled independently by a single resistor. In comparison with the previously reported circuits, the proposed configuration considerably reduces the number of passive elements.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with Three Inputs Using DDCCs

A new high input impedance voltage-mode universal biquadratic filter with three input terminals and five output terminals is presented. The proposed circuit uses three plus-type differential difference current conveyors, two grounded resistors and two grounded capacitors. The proposed circuit can realize all the standard filter functions: lowpass, bandpass, highpass, notch and allpass, without component matching conditions. The proposed circuit offers the features of high input impedance, low active and passive sensitivities and the use of only grounded resistors and capacitors.     

Cascadable Current-Mode Biquad Filter and Quadrature Oscillator Using DO-CCCIIs and OTA

This article introduces a circuit which can function both as a quadrature oscillator and as a universal biquad filter (lowpass, highpass, bandpass). When the circuit functions as a universal biquad filter, the quality factor and pole frequency can be tuned orthogonally via the input bias currents. When it functions as a quadrature oscillator, the oscillation condition and oscillation frequency can be adjusted independently by the input bias currents. The proposed circuit can work as either a quadrature oscillator or a biquad filter without changing the circuit topology. The amplitude of the proposed oscillator can be independently controlled via the input bias currents. The proposed oscillator can be applied to provide amplitude modulated/amplitude shift keyed signals with the above-mentioned major advantages. The circuit is very simple, consisting of four dual-output second generation current controlled current conveyors (DO-CCCIIs), one operational transconductance amplifier (OTA), and two grounded capacitors. Without any external resistors and using only grounded elements, this circuit is therefore suitable for IC architecture. PSPICE simulation results are depicted here, and the given results agree well with the theoretical analysis. The power consumption is approximately 7.32 mW at ±2.5 V supply voltages.     

基于CDCTA的双模式等幅正交振荡器

针对正交振荡器实现复杂、振幅不相等、模式单一等问题,提出了一种基于电流差分级联跨导放大器的双模式正交振荡器。该电路仅使用一个电流差分级联跨导放大器、一个接地电阻和两个接地电容,可以同时产生等幅电压和电流正交信号。电路结构简单,灵敏度低,易于集成,振荡条件和振荡频率可相互独立地电控调谐。PSPICE仿真与硬件实验结果验证了理论分析的正确性。     

Novel voltage/current-mode quadrature oscillator using current differencing transconductance amplifier

This letter proposes a new realization of voltage/current-mode (CM) quadrature oscillator (QO) using Current Differencing Transconductance Amplifier (CDTA) as the active element. The proposed circuit employs canonic number of components, namely two CDTAs, one resistor and two grounded capacitors. The oscillator is capable of providing two explicit quadrature current outputs and two quadrature voltage outputs. Moreover, the circuit enjoys the advantage of independent control of condition of oscillation (CO) and frequency of oscillation (FO). The non-ideal analysis and sensitivity study of the circuit has been carried out and the circuit exhibits a good sensitivity performance. B2SPICE simulation results are included that validate the working of the circuit.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with One Input and Five Outputs Using Current Conveyors

A new high input impedance voltage-mode universal biquadratic filter with one input terminal and five output terminals is presented. The proposed circuit uses three differential voltage current conveyors (DVCCs), four resistors, and two grounded capacitors. The proposed circuit can realize all the standard filter functions—lowpass, bandpass, highpass, notch, and allpass—simultaneously, without changing the passive elements. The proposed circuit enjoys the features of high input impedance, orthogonal control of resonance angular frequency and quality factor, use of only grounded capacitors, and low active and passive sensitivities.     

Quadrature oscillator using CCCCTAs and grounded capacitors with amplitude controllability

The realisation of two electronically tunable current-mode quadrature oscillators using Current Controlled Current Conveyor Tranconductance Amplifiers (CCCCTAs) and grounded capacitors is presented. The proposed circuits offer the following advantages. The condition of oscillation and the frequency of oscillation can be orthogonally controlled. Availability of electronic control of amplitude of output current is achieved. The oscillators have high outputs impedance which facilitates easy driving an external load without additional current buffers. The proposed circuits are constructed by using two active elements and all grounded capacitors which are attractive for integration and have low active and passive sensitivities. The PSPICE simulation and experimental results are included to show the workability of the proposed circuit.     

An electronically tunable current-mode quadrature oscillator using PCAs

This article presents a new realisation of active RC sinusoidal oscillator with electronically tunable condition and frequency of oscillation (FO). As compared to the class of three resistors, two capacitors (3R-2C)-based canonic oscillators, the circuit proposed here uses only two resistors and two capacitors as the passive components and still provides non-interactive tuning laws for the condition of oscillation and the FO. The proposed circuit employs new bipolar programmable current amplifier as the active building block and is capable of simultaneously providing two explicit quadrature current outputs. SPICE simulation results have been included to verify the workability of the circuit as an oscillator and the tuning range of the FO.     

Versatile multifunction universal voltage-mode biquadratic filter

A new versatile multifunction universal biquadratic filter with four inputs and four outputs employing one differential difference current conveyor, one full differential current conveyor, two grounded capacitors and two grounded resistors is proposed. The proposed configuration can be used as either three-input single-output voltage-mode universal filter with high-input and low-output impedance or single-input four-output voltage-mode multifunction filter with high-input impedance. It still maintains the following advantages: (i) the employment of only two current conveyors, (ii) the employment of only grounded capacitors, (iii) the employment of only grounded resistors, (iv) no need to employ inverting type input signals, (v) no need to impose component choice conditions to realize specific filtering functions and (vi) low active and passive sensitivity performances.     

Analytical synthesis of general high-order voltage/current transfer functions using CCIIs

This paper proposes two circuit structures to realize general high-order voltage and current transfer functions using second-generation current conveyors (CCIIs). The proposed general high-order voltage/current-mode circuit structures are designed based on an analytical synthesis method. The nth-order voltage-mode transfer function requires 2n+1 CCIIs, 2n+2 grounded resistors and n grounded capacitors. The nth-order current-mode transfer function requires 2n+2 CCIIs, 2n+2 grounded resistors and n grounded capacitors. The voltage-mode third-order allpass, lowpass and highpass filters and the current-mode third-order notch, lowpass and highpass filters that are derived out from the proposed high-order voltage and current-mode circuit structures are simulated to verify the synthesis methods.     

Universal capacitor-grounded voltage-mode filter with three inputs and a single output

For the first time, a universal voltage-mode filter with three inputs and a single output has been realized by employing two 'grounded' capacitors in addition to two active current conveyors and two resistors. The proposed circuit offers the following advantageous features: simultaneous realization of voltage-mode low-pass, band-pass, high-pass, notch and all-pass filter responses from the same configuration; no requirement of critical component matching conditions; no requirement of inverting-type voltage input signal; employment of two grounded capacitors ideal for integration; and low active and passive sensitivity performance. H-SPICE simulation results confirm the theoretical analysis.     

A Novel High CMRR High Input Impedance Differential Voltage-Mode KHN-Biquad Employing DO-DDCCs

In this work, a novel circuit configuration for realizing a differential voltage-mode Kerwin-Huelsman-Newcomb (KHN) biquad filter with high common-mode rejection ratio (CMRR) is presented. The proposed circuit is based on using the dual output differential difference current conveyor (DO-DDCC). The circuit uses three DO-DDCCs, two capacitors and five resistors. All the passive elements are grounded, which is important in integrated circuit implementation point of view. The differential voltage input signal is applied to high input impedance terminals, which is important in the voltage-mode operations. SPICE simulation results are included to verify the theory.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with Three Inputs and Six Outputs Using Three DDCCs

A new high input impedance voltage-mode universal biquadratic filter with three input terminals and six output terminals is presented. The proposed circuit uses three plus-type differential difference current conveyors (DDCCs), three resistors, and two grounded capacitors. The proposed circuit can realize all the standard filter functions, namely, lowpass, bandpass, highpass, notch, and allpass, simultaneously, without component matching conditions. The proposed circuit still offers the features of high input impedance, using only grounded capacitors, and orthogonal controllability of resonance angular frequency and quality factor.