Current Backward Transconductance Amplifier Research Articles

CC-CBTA-Based Floating Inductance Simulator with CM/VM PID Controllers

This work describes voltage-mode (VM), current-mode (CM) PID controllers and an electrically controllable floating inductance (FI) simulator circuit. Only a single current-controlled current backward transconductance amplifier (CC-CBTA) and a grounded capacitor are used in the proposed FI simulator circuit. One CBTA, one CC-CBTA, two capacitors and one resistor are used in the proposed PID controllers. All of the proposed circuits have appropriate input and output impedance values, allowing them to be utilized in cascade connections without requiring a buffer circuit. There is also no matching constraint between the active and passive values of the proposed circuit. The SPICE software environment and experimental results were used to validate theoretical derivations and associated outcomes. The layout of the CC-CBTA has been built, and the post-layout simulations are carried out using the netlist extracted from the layout. Comparisons were made with similar circuits found in the professional literature.

Design of Wide Bandwidth, High-CMRR Voltage and Transadmittance-Mode Instrumentation Amplifier Using a Single CBTA

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 Floating Memristor Based on CBTA with Grounded Capacitors

This paper presents a new floating memristor emulator (FME) consisting of only a single current backward transconductance amplifier (CBTA) as the active element and two grounded capacitors. The proposed FME-based on CBTA enjoys some advantages that include minimum active and passive elements without using an analog multiplier circuit and grounded passive elements which are attractive for the integrated circuit. In addition, excluding the DC power supply voltage, it does not use bias voltage and/or bias current. The designed memristor circuit provides incremental and decremental characteristics without changing circuit topology or using a switching mechanism and it is implemented with a minimum of circuit elements. All simulation results for the memristor emulator were obtained as expected when compared with fabricated memristors.

Resistorless Current-Mode First-Order All-Pass Filter with Electronic Tuning Employing Low-Voltage CBTA and Grounded Capacitor

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[Formula: see text]nm level-7 CMOS process BSIM3v3 parameters with [Formula: see text]0.45[Formula: see text]V supply voltages were used. The proposed resistorless CBTA-C APF provides easy electronic tuning of the pole frequency in the frequency range from 763[Formula: see text]kHz to 17.6[Formula: see text]MHz, which is more than one decade. Maximum power dissipation of the circuit is 828[Formula: see text][Formula: see text]W at bias current 233[Formula: see text][Formula: see text]A. Nonideal, 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.

Memristor emulator circuits using single CBTA

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 0.18μm level-7 TSMC CMOS technology parameters is also proposed. It uses 23 CMOS transistors operating with the ±0.9V DC supply voltage. Theoretical derivations and related results are validated using SPICE simulations.

Electronically tunable sinusoidal oscillator circuit with current and voltage outputs

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.

Component reduced floating ± L, ± C and ± R simulators with grounded passive components

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 μm TSMC level-7 CMOS technology parameters.

Current and voltage transfer function filters using a single active device

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.

Current mode leapfrog ladder filters using a new active block

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.