scholarly journals Electronically Adjustable Grounded Memcapacitor Emulator Based on Single Active Component with Variable Switching Mechanism

Electronics ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 161
Author(s):  
Predrag B. Petrović

New current mode grounded memcapacitor emulator circuits are reported in this paper, based on a single voltage differencing transconductance amplifier-VDTA and two grounded capacitors. The proposed circuits possess a single active component matching constraint, while the MOS-capacitance can be used instead of classical capacitance in a situation involving the simulator working within a high frequency range of up to 50 MHz, thereby offering obvious benefits in terms of realization utilising an IC-integrated circuit. The proposed emulator offers a variable switching mechanism—soft and hard—as well as the possibility of generating a negative memcapacitance characteristic, depending on the value of the frequency of the input current signal and the applied capacitance. The influence of possible non-ideality and parasitic effects was analysed, in order to reduce their side effects and bring the outcome to acceptable limits through the selection of passive elements. For the verification purposes, a PSPICE simulation environment with CMOS 0.18 μm TSMC technology parameters was selected. An experimental check was performed with off-the-shelf components-IC MAX435, showing satisfactory agreement with theoretical assumptions and conclusions.

2014 ◽  
Vol 530-531 ◽  
pp. 1100-1107
Author(s):  
Hai Zhen He ◽  
Jun Kuang ◽  
Xin Liu ◽  
Xin Hang Huang ◽  
Mei Li Cao

In this paper, a signal flow graph structure of current-mode multifunction filter using current differencing transconductance amplifier (CDTA) is presented. The proposed configuration is comprised of two grounded capacitors and four CDTAs. They exhibit low-input and high-output impedances, which is very convenient for integrated circuit implementation. The presented filter configuration can realize all the standard filter functions simultaneously, lowpass (LP), bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP), without any component matching conditions. The natural frequency () and the bandwidth () of the proposed filter can be electronically tuned by varying the bias current of the CDTA. PSPICE simulation results are included to confirm the theory.


2013 ◽  
Vol 22 (09) ◽  
pp. 1340001 ◽  
Author(s):  
JIUN-WEI HORNG ◽  
TO-YAO CHIU ◽  
CHING-PAO HSIAO ◽  
GUANG-TING HUANG

A current-mode universal biquadratic filter with three input terminals and one output terminal is presented. The architecture uses two current conveyors (CCs), two grounded capacitors and two grounded resistors; and can realize all standard second-order filter functions — highpass, bandpass, lowpass, notch and allpass. Moreover, the circuit still offers the following advantage features: very low active and passive sensitivities, using of grounded capacitors and resistors which is ideal for integrated circuit implementation, without requirements for critical component matching conditions and very high output impedance. The workability of the proposed circuit has been verified via HSPICE simulations using TSMC 0.18 μm, level 49 MOSFET technology.


2006 ◽  
Vol 15 (05) ◽  
pp. 701-717 ◽  
Author(s):  
HSIAO WEI SU ◽  
YICHUANG SUN

A high-frequency highly linear tunable CMOS multiple-output operational transconductance amplifier (MO-OTA) for fully balanced current-mode OTA and capacitor (OTA-C) filters is presented. The MO-OTA is based on the cross-coupled pairs at the input and provides two pairs of differential outputs. A simple common-mode feedback (CMFB) circuit to stabilize the DC output levels of the MO-OTA is also proposed and two such CMFB circuits are used by the MO-OTA. The proposed MO-OTA is suitable for relatively low voltage (2.5 V) applications as its circuit has only two MOS transistors between the supply and ground rails. Simulated in a TSMC 0.25 μm CMOS process using PSpice, the MO-OTA has at least ± 0.3 V linear differential input signal swing with a single 2.5 V power supply and operates up to 1 GHz frequency. The MO-OTA has a THD less than -46 dB for a differential input voltage of 0.9 Vp-p at 10 MHz, dynamic range (DR) at THD = -46 dB is over 50 dB, and power consumption (with the common-mode feedback circuit) is below 8 mW for the whole tuning range. A fully balanced multiple loop feedback current-mode OTA-C filter example using the proposed MO-OTA is presented. This example also shows that the current-mode follow-the-leader-feedback (FLF) structure can achieve good performances for OTA-C filter design.


Circuit World ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kapil Bhardwaj ◽  
Mayank Srivastava

Purpose The purpose of the paper is to report an emulation configuration of a three pinch-off memristor (TPM), whose transient characteristics consist three cross-over points on the voltage-current plane, which is dissimilar to a conventional memristor. These characteristics can be very useful in memristor-based multi-bit memory devices and hyperchaotic oscillators. Design/methodology/approach The work describes the Mathematical framework for TPM and a circuit emulator based on the derived conditions. The configuration is based on five operational transconductance amplifier (OTAs) and four grounded passive elements. After which, we have verified its operation using personal simulation program with integrated circuit emphasis simulation environment. Finally, the implementation of OTA-based TPM using commercial integrated circuit (IC) LM13700 has also been presented. Findings It has been shown that a flux-dependent memductance expression of cubic order can show three intersections on the VI contour under certain parameter related constraints. Moreover, the OTA-based emulator reported in the work is very compact in nature because of the no use of external multiplier IC/circuitry, which has been popular in previous emulators. Originality/value For the first time, a multiple cross-over memristor emulator has been reported which can operate under practical operating conditions such as at practical operating frequencies and sinusoidal excitation.


2013 ◽  
Vol 22 (03) ◽  
pp. 1350007 ◽  
Author(s):  
LEILA SAFARI ◽  
SHAHRAM MINAEI ◽  
ERKAN YUCE

In this paper, a novel first-order current-mode (CM) electronically tunable all-pass filter including one grounded capacitor and two dual-output current followers (DO-CFs) is presented. The used DO-CFs are implemented using only 10 MOS transistors granting the proposed CM all-pass filter extremely simple structure. The proposed filter is suitable for integrated circuit (IC) fabrication because it employs only a grounded capacitor and is free from passive component matching conditions. Interestingly the introduced configuration uses minimum number of components compared to other works. It also offers other interesting advantages such as, alleviating all disadvantages associated with the use of resistors, easy cascadability and satisfies all technology requirements such as small sizing, simple realization, low voltage and low power operation. Additionally, the circuit parameters can be easily set by adjusting control voltages. Most favorably, the proposed CM all-pass filter can be simply used as a voltage-mode (VM) all-pass filter with outstanding properties of adjustable gain and tunability. To further show the versatility of the proposed structure a sinusoidal oscillator is also derived from presented CM all-pass filter. Nonideal gain and parasitic impedance effects on developed CM filter are discussed. Finally, simulation results with SPICE program are included to confirm the theory.


2019 ◽  
Vol 28 (12) ◽  
pp. 1950205
Author(s):  
Yong-An Li

From the nodal admittance matrix (NAM) expansion approach and 16 pathological patterns of the voltage differencing transconductance amplifier (VDTA), two different categories, namely sort A and sort B, of the quadrature sine-wave oscillators-employed VDTAs and grounded capacitors in the current mode are synthesized. In all, four quadrature sine-wave oscillators with two sets of quadrature current outputs are attained. Because canonic number is used for component quantity, the oscillators are appropriate to integrated circuit realization and also provide electronic, linear, and orthogonal adjustments between the oscillation criterion and frequency by means of tuning bias currents of the VDTAs. The paper-and-pencil and simulation analyses as well as experimental analysis have been carried out to check the utilized synthesis approach.


2004 ◽  
Vol 14 (03) ◽  
pp. 690-695
Author(s):  
A. GHORI ◽  
P. GHOSH

Operational Transconductance Amplifier (OTA) is an excellent current mode device suited very well for VLSI implementation. In this contribution we report realization of OTA using Silicon-On-Insulator (SOI) structure based MOSFETs and compared them to OTA designed with bulk MOSFET. SOI based OTA outperformed bulk MOSFET OTA giving close to 10 GHz improvement in high frequency f T . A band-pass filter was implemented with SOI based OTA with a center frequency of 7 GHz and a bandwidth of 480 kHz.


Author(s):  
Dr. D. D. Mulajkar ◽  

A new electronically tunable current-mode third order filter is proposed in this paper. OP-AMP is used as an active building block. With current input the filter can realize band pass responses in current mode. The filter circuit realizes calculated transfer function. The other attractive features of the filter are a) Employment of minimum active and passive elements b) Responses are electronically tunable c) Low active and passive sensitivities d) Suitable for high frequency operation e) Ideal for integrated circuit implementation.


2014 ◽  
Vol 23 (06) ◽  
pp. 1450084 ◽  
Author(s):  
SAKSIT SUMMART ◽  
CHANCHAI THONGSOPA ◽  
WINAI JAIKLA

This paper presents three current-mode quadrature oscillator (QO) circuits based on dual-output current differencing transconductance amplifier (DO-CDTA) which is designed from block diagram. The proposed circuits consist of two DO-CDTAs and two grounded capacitors. The circuits can provide two sinusoidal output currents with 90° phase difference. The condition of oscillation (CO) can be adjusted independently from the frequency of oscillation (FO) by adjusting the bias currents of the DO-CDTA. The proposed circuits have high output impedance appropriate for cascade connection application in current mode which is capable to directly drive load. The circuits use only grounded capacitors without any external resistor which is very appropriate for further development into an integrated circuit. Moreover, the oscillator circuits can also adjust amplitude of the output signal. The results of PSPICE simulation program are corresponding to the theoretical analysis.


Sign in / Sign up

Export Citation Format

Share Document