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ABSTRACT In this paper, four new generalized configurations of grounded parallel‐type immittance simulators are proposed. These circuits implement parallel resistor–inductor (RL), parallel resistor–capacitor (RC), parallel capacitor–frequency‐dependent negative resistance (CD), and capacitance multiplier configurations utilizing only two second‐generation voltage conveyors (VCII±) as active elements along with three impedances, without the need for specific matching conditions. The applicability of the proposed parallel RL and capacitance multiplier configurations as a second‐order high‐pass filter (HPF) and a first‐order low‐pass filter (LPF), respectively, is also demonstrated. These applications illustrate the versatility and utility of the proposed structures. Frequency, transient, and Monte Carlo analysis utilizing the CMOS VCII± in the SPICE simulation tool have also been performed to validate the feasibility of the presented circuits. Further validation is carried out through layout design in Cadence Virtuoso, employing 0.18‐μm CMOS technology. Both presimulation and postsimulation results are presented for a thorough assessment of the proposed circuits. Also, the claimed theory is verified by experimental results based on the VCII implementation with commercially available IC AD844. [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]

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]

Summary: In the past, several new active elements have been employed to realize single‐resistance‐controlled oscillators (SRCO) of which the four‐terminal‐floating‐nullors (FTFN) have attracted considerable attention in the literature. In this paper, an ingenious methodology of deriving single‐FTFN‐based canonic grounded‐capacitor (GC) SRCOs has been presented. It is shown that such oscillators can be systematically evolved from a class of earlier known op‐amp‐based SRCOs through the application of two theorems pertaining to RC‐nullor oscillators published earlier. The presented methodology not only yields all the previously known (four) single‐FTFN‐based canonic GC SRCOs but also reveals a number of (12) new circuits, which have not been known in the open literature earlier. The viability of the evolved oscillator circuits has been confirmed through SPICE simulations, and some simulation results have been given. [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]

In this paper, a grounded lossy inductance (parallel RL type) simulator circuit employing an operational transresistance amplifier (OTRA), five resistors, and a virtually grounded capacitor is proposed. The value of simulated inductor can be controlled independently through a grounded resistance and/or virtually grounded capacitor without affecting the parallel equivalent resistance. Application examples using the presented lossy inductor have been provided. The performance of the application examples has been verified by sample experimental results employing an OTRA implemented using AD844‐type current feedback operational amplifiers. [ABSTRACT FROM AUTHOR]