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This paper presents a new circuit approach to realize a capacitance multiplier circuit with positive and negative multiplication factors. Based on this approach, two new implementations of positive and negative grounded capacitance multiplier (GCM) circuits are proposed, which utilize only one current follower differential input transconductance amplifier (CFDITA), in conjunction with only one resistor and one virtually grounded capacitor. The presented GCM circuits can enhance a low capacitance value to a very high value (used in low frequency applications), up to 9202 times its original value. An important aspect of the proposed circuits involves designing a lossy parallel inductor circuit by interchanging the passive elements (RC:CR transformation) with each other. The obtained value of the capacitance and inductance can be controlled independently and electronically through the transconductance of CFDITA. The practical usability of the suggested circuits as first and second order filters is discussed. The functionality of the proposed GCM circuits is validated using CMOS CFDITA implemented with 180 nm TSMC technology parameters. Experimental verification of the proposed circuits and application examples is reinforced through the utilization of CFDITA implemented with readily available ICs AD844 and LM13700. These outcomes emphasize the dependability of the suggested circuits. [ABSTRACT FROM AUTHOR]

Summary: In this communication, two new positive lossy series inductor simulator circuits using single current differencing buffered amplifier (CDBA), one capacitor, and three resistors are presented. In both the proposed circuits, the inductance value is independently controllable through a grounded resistor, which may be implemented using a voltage‐controlled resistor (VCR), facilitating electronic tuning. Moreover, one of the circuits presented utilizes the intrinsic resistance (internal resistance available at input ports p and n) of the CDBA, thereby enabling electronic control and establishing the inductor simulator as canonical. Both the circuits are analyzed for non‐ideal behavior by taking into account the parasitic elements of CDBA and compared with their ideal counterparts. To demonstrate the efficacy of the proposed series RL simulator circuits, SPICE simulations are performed using CMOS CDBA, and the performance of the proposed circuits is evaluated by designing a lead compensator. The simulation and experimental results of the proposed circuits, along with the application examples employing CDBA realized with the off‐the‐shelf available IC AD844, have also been corroborated. [ABSTRACT FROM AUTHOR]

A new first‐order universal filter structure is presented in this article using a single differential difference current conveyor (DDCC). The proposed circuit can provide three first‐order filter functions namely, high‐pass filter (HPF), low‐pass filter (LPF), and all‐pass filter (APF) in voltage mode (VM) and transadmittance mode (TAM) both. A voltage amplifier with a gain of 2 is required for the realization of the APF functions in both the modes while for LPF and HPF, no condition is required. The pole frequency and gain of the proposed circuit can be controlled separately. The effect of the parasitic impedances of the DDCC has been modeled in the nonideal equivalent circuit from which nonideal parameters have been evaluated and compared with their ideal ones. Application examples of the proposed circuits configured as amplitude equalizer (in both modes) and in the realization of a simple wideband band‐pass filter are also discussed. The functionality of the proposed circuit as well as its mentioned application circuits is verified using complementry metal oxide semiconductor DDCC to support the theoretical propositions. Some experimentally observed frequency responses and transient responses of the various VM filters have also been corroborated using DDCC implemented using AD844 ICs. [ABSTRACT FROM AUTHOR]

Summary: A new synthetic floating simulator topology is proposed which realizes lossy parallel inductance (R‐L), lossy parallel capacitance (R‐C), lossy parallel C‐D, and lossless floating capacitance multiplier (FCM) circuits using only three current feedback operational amplifiers (CFOA) as active elements and three impedances. In all the presented circuits, the value of L, C, and D is independently controllable through a single resistance without requiring any matching condition for passive elements. A novel feature of the proposed circuit involves a straightforward adjustment in the CFOA connections, allowing the circuit to function as either a floating lossless immittance simulator or a floating series‐type lossy immittance simulator. Various application examples of the presented circuits such as lead compensator, lag compensator, first‐order high‐pass filter, and fourth‐order Butterworth filter are also given to justify the theoretical analysis. To validate the workability of the proposed circuits, several analyses are conducted, including frequency analysis, transient analysis, Monte‐Carlo analysis, and temperature analysis, using the macro‐model of AD844 in the SPICE simulation tool. Experimental results of the parallel R‐L simulator and application examples are also provided using commercially available IC AD844‐type integrated CFOAs. [ABSTRACT FROM AUTHOR]

This communication presents two new first order universal active filter configurations employing operational transconductance amplifiers (OTA) and use grounded capacitor which is prominently suitable for integrated chip (IC) fabrication. One of the proposed topologies provides voltage mode (VM) and transconductance mode (TCM) of operations while the other circuit provides current mode (CM) in addition with transresistance mode (TRM) filter functions. All three first order filter functions namely low pass filter (LPF), high pass filter (HPF) and all pass filter (APF) are configurable with appropriate choice(s) of input voltage/current signals. An equal transconductor condition (which can be easily achieved) is required for the realization of APF functions. The proposed filter configurations possess high input impedance and high output impedance and also offer independent electronic tunability of pole frequency/cut-off frequency. The gain of filters realized in VM, TCM and TRM has independent electronic tunability feature and can be adjusted through transconductor. For the usability of proposed filters, multi-phase sinusoidal oscillator has also been demonstrated. To assure the workability of the proposed filter structures, PSPICE simulations with CMOS OTA implemented in 0.18 µm TSMC technology parameters has been used. Various simulation results including Monte-Carlo simulations, process corner analysis, total harmonic distortions (%THD) and temperature analysis have also been appended. Experimental results employing off-the-shelf IC LM13700 type OTAs have also been included to verify the theoretical propositions of first order universal filters and multiphase sinusoidal oscillators. [ABSTRACT FROM AUTHOR]

In this paper, a new lossy capacitance multiplier (CM) circuit using a single current follower differential input transconductance amplifier (CFDITA), one resistor and one capacitor (virtually grounded) is presented. The proposed circuit does not require any passive component matching constraints and has independently controllable equivalent capacitance with a multiplication factor up to 7102. Both ideal and non‐ideal analyses of the proposed CM circuit are carried out and compared. The performance of the proposed CM circuit is validated using a CMOS CFDITA and its validity is supported by various analyses including frequency analysis, transient analysis, Monte‐Carlo analysis and temperature analysis. The workability of the proposed circuit is also tested using layout design, and its pre and post‐simulated results are appended. The results are further confirmed with experimental results using the AD844 and LM13700 ICs with CFDITA implementation. [ABSTRACT FROM AUTHOR]

This communication presents two new voltage mode (VM) third-order quadrature sinusoidal oscillator (TOQSO) configurations employing three operational transresistance amplifiers (OTRAs), six resistors and three virtually grounded capacitors. The proposed circuits have independent control of condition of oscillation (CO) and frequency of oscillation (FO) utilizing the intrinsic current differencing property of the OTRA. The proposed TOQSOs have ideally zero output impedance, a feature suitable for easy cascadability. Nonideal and sensitivity analyses have been carried out and compared with those obtained from ideal analysis. The presented TOQSOs have been simulated using OTRAs implemented with macro model of off-the-shelf available AD844 ICs. Experimental results have also been included using OTRAs realized with commercially available AD844 CFOA ICs. [ABSTRACT FROM AUTHOR]

Summary: In this communication, three new negative‐grounded capacitance multiplier (NGCM) circuits employing a single current feedback operational amplifier (CFOA), two resistors, and a grounded capacitor (which is most suitable for parasitic absorption and also IC implementation point of view) are investigated. No matching constraints are required for any of the proposed circuit realizations. Out of the three proposed circuits, multiplication factor of one of the capacitance multiplier can be controlled electronically as the controlling resistor is grounded, which can easily be replaced by a voltage‐controlled resistor (VCR). Error analysis of the proposed NGCMs has been carried out, and the results have been compared with those obtained from ideal analysis. To substantiate the feasibility of the proposed circuits, macro model of CFOA has been used, and the simulations have been performed in Personal Simulation Program with Integrated Circuit Emphasis (PSPICE). Simulation results for frequency analysis, Monte‐Carlo analysis, and temperature analysis have been included for the theoretical justification. Noise analysis and power supply rejection ratio analysis have also been carried out for the proposed circuits. The multiplication factors of the proposed NGCMs have been obtained up to a maximum value of 2001. The impedance and phase of the proposed NGCM structures are insensitive with temperature. The functionality of the proposed structures has also been validated experimentally using commercially available IC AD844‐type CFOA. [ABSTRACT FROM AUTHOR]

This communication presents a systematic realization of two new third-order quadrature sinusoidal oscillators employing operational transconductance amplifiers (OTAs). These oscillators use canonical number of transconductors (four) and canonical number of grounded capacitors (three). The proposed oscillators enjoy independent electronic control of the condition of oscillation (CO) and frequency of oscillation (FO). The independent electronic adjustment of FO through two identical transconductances controlled by a single external voltage (without disturbing CO) is beneficial in designing voltage-controlled oscillators (VCOs). The presented oscillators have high-frequency stability factor and low power consumption. Circuit simulations employing CMOS OTAs and experimental results using off-the-shelf available OTA IC LM13700 have also been included to confirm the workability of the presented circuits. [ABSTRACT FROM AUTHOR]

This paper introduces an electronically tunable mixed-mode universal biquad filter configuration employing four single output operational transconductance amplifiers (OTAs), one dual output OTA and two grounded capacitors (GCs) (ideal for integrated circuit implementation and absorbing shunt parasitic capacitances). The presented structure can realize all second-order filter functions, namely, low pass (LP), high pass (HP), band pass (BP), band reject (BR) and all pass (AP) responses in voltage mode (VM), current mode (CM), transresistance mode (TRM) and transconductance mode (TCM) using appropriate selection(s) of input signals. The cut-off frequency ( f o) and bandwidth (BW) of the realized filters can be tuned orthogonally through the transconductance (by varying the bias currents) of the OTAs. The proposed biquad configuration enjoys low active and passive sensitivities. The workability of this multifunctional biquad filter topology has been confirmed through simulations using MATLAB and Analog Design Environment (ADE) spectre tool provided by Cadence Virtuoso, using 0.18 μ m CMOS process parameter. The post-layout simulations have also been carried out to validate the theory. [ABSTRACT FROM AUTHOR]