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Minaei, Shahram (Dogus Author) In this paper, new analog memristor emulator circuits based on current backward transconductance amplifier (CBTA) and passive elements are proposed. They emulate both types of memristor (incremental and decremental) just by interchanging the CBTA output terminals. It uses only one CBTA, two resistors, one capacitor and one multiplier emulating grounded memristor. They consist of less CMOS transistors and have wider output ranges compared to other designed emulator circuits. The CMOS implementation of the CBTA using 0.18 ttm level-7 TSMC CMOS technology parameters is also proposed. It uses 23 CMOS transistors operating with the +/- 0.9 V DC supply voltage. Theoretical derivations and related results are validated using SPICE simulations.

In this work, a CBTA-based universal mutator circuit is proposed for the realization of memcapacitor and meminductor elements. Proposed mutator circuit contains only one CBTA element, one memristor and one capacitor. It is suitable to transform a grounded memristor to a floating memcapacitor or meminductor. SPICE simulation by using a CBTA designed with 0.18 μm level-7 TSMC CMOS transistors was performed to show the accuracy of the proposed circuit and as a result, frequency dependent hysteresis loops are obtained.

In this paper, a new realization of a current-mode first-order all-pass filter (APF) using a single active building block (ABB) and one grounded capacitor is presented. As the ABB, the current backward transconductance amplifier (CBTA) is used, which is one of the most recently reported active elements in the literature. The theoretical results are in detail verified by numerous SPICE simulations using a new low-voltage implementation of CBTA. In the design, the PTM 90 nm level-7 CMOS process BSIM3v3 parameters with ±0.45 V supply voltages were used. The proposed resistorless CBTA-C APF provides easy electronic tuning of the pole frequency in frequency range from 763 kHz to 17.6 MHz, which is more than one decade. Maximum power dissipation of the circuit is 828 W at bias current 233 A. Non-ideal, parasitic effects, sensitivity analyses, temperature and noise variation, current swing capability, and Monte Carlo analysis results are also provided. Compared to prior state-of-the-art works, the proposed CBTA-C APF has achieved the highest Figure of Merit value, which proves its superior performance. In this paper, a new realization of a current-mode first-order all-pass filter (APF) using a single active building block (ABB) and one grounded capacitor is presented. As the ABB, the current backward transconductance amplifier (CBTA) is used, which is one of the most recently reported active elements in the literature. The theoretical results are in detail verified by numerous SPICE simulations using a new low-voltage implementation of CBTA. In the design, the PTM 90 nm level-7 CMOS process BSIM3v3 parameters with ±0.45 V supply voltages were used. The proposed resistorless CBTA-C APF provides easy electronic tuning of the pole frequency in frequency range from 763 kHz to 17.6 MHz, which is more than one decade. Maximum power dissipation of the circuit is 828 W at bias current 233 A. Non-ideal, parasitic effects, sensitivity analyses, temperature and noise variation, current swing capability, and Monte Carlo analysis results are also provided. Compared to prior state-of-the-art works, the proposed CBTA-C APF has achieved the highest Figure of Merit value, which proves its superior performance.

Frictional heating of articulating surfaces may influence the rate of wear, fatigue, creep and oxidative degradation of bearing materials. Also temperature rise can damage the surrounding tissue and lubricant around the artificial joint and contributes insert loosening. The objective of this study is to determine temperature rise between sliding surface of vitamin E blended UHMWPE and conventional UHMWPE acetabular component paired with a cobalt–chromium–molybdenum (CoCrMo) femoral component, as a function of sliding time and applied load. Besides the experimental studies, the frictional temperature rise of conventional UHMWPE was theoretically calculated. Frictional measurements of the joints were carried out on a custom made hip joint friction simulator. The diameter of the prostheses was 28 mm. Applied static loads were changed from 200 N to 1500 N. In flexion–extension plane, a simple harmonic oscillatory motion between ±24° was applied to the UHMWPE acetabular component. The period of motion was 1 Hz and the tests were run up to 11,000 cycles. Temperature rise in acetabular and femoral component was recorded with embedded thermocouples. Both the experimental temperature rise values and theoretical calculations results were compared and evaluated.

In this work, a high-performance voltage and current output instrumentation amplifier circuit is proposed. The proposed circuit also has voltage-mode (VM) and transadmittance-mode (TAM) outputs at a time. It employs a single current backward transconductance amplifier (CBTA) and a grounded resistor. It has the advantage of having low input and high output impedances which makes it easy for cascadability. The presented circuit has electronically tunable property due to the bias current of the CBTA. The validity of the proposed circuit is demonstrated by PSPICE simulations using a 0.18[Formula: see text][Formula: see text]m CMOS process with [Formula: see text][Formula: see text]V supply voltage. Simulation results show that the proposed circuit has a high common mode rejection ratio (CMRR), wide bandwidth, low offset and high gain properties.

A new circuit for realisation of the mutually coupled circuit, which is also called the synthetic transformer, is proposed. The proposed circuit uses two current controlled current conveyor transconductance amplifiers (CC-CCTAs), one grounded resistor and two grounded capacitors. The primary self-inductance, the secondary self-inductance and the mutual inductance can be independently controlled and can be tuned electronically by changing the biasing current of the CC-CCTAs. It uses two grounded capacitors which are suitable from the point of integrated circuit implementation. It has a good sensitivity performance with respect to tracking errors and passive components. The validity of the proposed circuit is demonstrated by PSpice simulations.

Minaei, Shahram (Dogus Author) The aim of this paper is proposing an alternative method to Gorski-Popiel Technique in realization of synthetic transformers. A new synthetic floating transformer (FT) circuit is also given. The proposed synthetic transformer circuit uses two current backward transconductance amplifiers (CBTAs), three resistors, and two grounded capacitors. The primary selfinductance, the secondary self-inductance, and the mutual inductance can be independently controlled and can be tuned electronically by changing the biasing current of the employed CBTAs. It has a good sensitivity performance with respect to tracking errors. A band-pass filter is also realized to test the performance of the proposed synthetic transformer circuit. The validity of the proposed synthetic transformer circuit is demonstrated by PSPICE simulations and experimental results.

WOS: 000305815300015, In this study, a novel second order universal filter using current-feedback amplifier, commercially available active component, is presented. The signal-flow graph method is used to synthesize the filter. The proposed filter has three high impedance input and one output, (multiple input single output (MISO) configuration). It can generate all biquadratic filtering functions namely: low-pass (LP), band-pass (BP), high-pass (HP), band-reject (BR) and all-pass (AP) at the output terminal by selecting different input signal combinations. The validity of the proposed circuits is demonstrated by simulations. (C) 2011 Elsevier GmbH. All rights reserved.

WOS: 000255999900002, A novel current controllable floating or grounded inductor simulator circuit with minimum elements is proposed. The circuit uses two dual output- second generation current controlled conveyors (DO-CCCIIs) with parasitic resistance at terminal X and one grounded capacitor externally connected. Proposed circuit is suitable for fully integrated circuit design. Analysis and simulation results are included.

A general synthesis procedure is given for a versatile signal flow graph realization of a general current transfer function by using multi-output second generation current controlled current conveyors (MO-CCCIIs). The proposed configuration uses n + 1 multi-output second generation current conveyors (MO-CCIIs), n capacitors and at most 2 ( n + 1 ) resistors. This number of resistors can be reduced to n for special cases. Using MO-CCCIIs instead of MO-CCIIs, the resistors can be removed completely for the n th-order universal structure. The general transfer function having any numerator dynamics can be derived from the universal structure by using a single MO-CCCII and at most n + 1 resistors. It is very easy to find the values of the passive elements from the coefficients of the transfer function to be realized. The validity of the proposed synthesis is verified through PSpice simulations.

A general synthesis procedure is given for a versatile signal flow graph realization of a general transfer function by using current differencing buffered amplifier (CDBA). The proposed configuration uses n + 1 CDBAs, n capacitors and at most 2 n + 4 resistors. This number of resistors can be reduced to n + 1 for special cases. The circuit is eligible to obtain a variety of transfer characteristics with the same common denominator polynomial, and it is easily converted to different modes of operations. It is straightforward to find the values of the passive elements from the coefficients of the transfer function to be realized. Simulations results are obtained by using commercially available active component AD844 and CMOS technology as well. All of these make the proposed circuit attractive.

WOS: 000298836500016, …

WOS: 000306287700007, A new circuit configuration for the realisation of an electronically tunable sinusoidal oscillator is presented. The proposed circuit uses only one current backward transconductance amplifier (CBTA), two grounded capacitors and one resistor. Using current controlled CBTA (CC-CBTA) instead of the CBTA, the resistor can be completely removed. It has also current-mode (CM) and voltage-mode (VM) outputs, simultaneously. The workability of the proposed structure has been demonstrated by both simulation and experimental results.

WOS: 000305249000013, In this paper, a general electronically tunable resistorless biquad, which realizes current ratio transfer function using current backward transconductance amplifiers is proposed. The biquad contains only two active components and two grounded capacitors, which make it convenient for production by the integrated circuit technology. The proposed biquad realizes all of the basic second order filter characteristics: low pass, high pass, band pass, band reject, and finally all pass. It is convenient for cascading with other similar biquads as well as with any two-port circuit with low impedance input to achieve higher order filter characteristics. The simulations that are performed using PSPICE simulator exhibit satisfactory results coherent with the theory.

WOS: 000293993200006, In this study, a novel immittance simulator circuit is proposed. The proposed circuit can simulate any one of the floating positive or negative inductor simulator (+/- L), positive or negative capacitor simulator (+/- C) and positive or negative resistor simulator (+/- R). It uses only one current backward transconductance amplifier (CBTA) and two grounded passive components. The proposed simulator can be tuned electronically by changing the transconductance value of the CBTA. Moreover, the circuit does not require any conditions of component matching. It has a good sensitivity performance with respect to the tracking errors and the passive components. The performance of the proposed immittance simulator is demonstrated on the fourth-order voltage- and current-mode band-pass filters by using Pspice simulations based on the 0.25 mu m TSMC level-7 CMOS technology parameters. (C) 2011 Elsevier GmbH. All rights reserved.

WOS: 000277662900002, In this paper, a new multi-terminal active component, namely current backward transconductance amplifier (CBTA) is proposed. The design procedure for the systematic realization of current-mode ladder filters using proposed active component is also presented. In order to demonstrate that the CBTA considerably simplifies the leapfrog structure of the current-mode ladder filters, a fifth-order Butterworth low-pass filter that requires a minimum of active components is presented. The theoretical results are demonstrated by using PSPICE simulation. (C) 2009 Elsevier GmbH. All rights reserved.

WOS: 000266329400012, In this letter, a new floating inductance simulator circuit is presented. The proposed structure consists of only one grounded capacitor without any external resistors and two different active elements. The active elements are dual-output current-controlled current conveyor (DO-CCCII) and operational transconductance amplifier (OTA). The proposed inductance simulator can be tuned electronically by changing the biasing current of the DO-CCCIIs or by changing the current of the OTA. Moreover, the circuit does not require any conditions of component matching. It has a good sensitivity performance with respect to tracking errors. As an application, the proposed inductance simulator is used to construct a fourth-order resistively terminated LC band-pass filter. The theoretical analysis is verified by the SPICE simulation results. (C) 2008 Elsevier GmbH. All rights reserved.

WOS: 000254240200009, A flexible synthesis procedure for electronically tunable nth-order current-mode (CM) universal filter using state variable-method is given. The proposed configuration uses n+1 multi-output second generation current conveyors (MO-CCIIs), n capacitors and n resistors. These resistors can be removed by using multi-output second generation current controlled conveyors (MO-CCCIIs) instead of MO-CCIIs. It is straightforward to find the values of the passive elements from the coefficients of the transfer function to be realized. The validity of the proposed filter is verified through PSpice simulations.

WOS: 000264490800009, A novel resistorless oscillator is presented. The proposed structure enjoys electronic tunability property with minimum number of active and passive components. This oscillator uses a current-mode (CM) active device and has properties of current mode circuits. The validity of the proposed circuit is verified by experimental results.

WOS: 000275012900009, In this study, current and voltage transfer function filters using single active component, namely, current backward transconductance amplifier (CBTA) are presented. The proposed structures are a single-input three outputs (SITO) current-transfer function filter, a single-input four-output (SIFO) voltage transfer function filter and three-input single-output (TISO) voltage transfer function filter. The proposed filters have low active and passive sensitivities and use canonical number of electronics components. The validity of the proposed circuits is demonstrated by PSPICE simulations and experimental results. Operation range of the CBTA and its parasitic effects are also discussed.

A new electronically tunable universal filter with single-input, triple-output employing only four elements (two capacitors and two negative-type second generation current controlled conveyors (CCCII)) is proposed. The proposed filter realises three basic filter functions simultaneously: lowpass, highpass and bandpass. The validity of the proposed filter is verified through PSPICE simulations.