Entity

Time filter

Source Type

Xianyang, China

Li Y.-A.,Xianyang Normal University
AEU - International Journal of Electronics and Communications | Year: 2012

The paper presents a series of basic circuits based on CFTAs (current follower transconductance amplifier), which contain amplifier, lossless integrator, first-order universal current-mode filter, simulation resistor, negative resistance converter, gyrator, capacitor multiplier, and frequency-dependent negative resistance circuit. Having used canonic number of grounded capacitors and resistors, the circuits are easy to be integrated and the parameters of the circuits can be adjusted electronically by tuning bias currents of the CFTAs. It is noted that the results of circuit simulations are in agreement with theory. © 2012 Published by Elsevier GmbH. All rights reserved. Source


Li Y.,Xianyang Normal University
International Journal of Electronics | Year: 2012

This article presents a novel current-mode multiphase sinusoidal oscillator. The oscillator can produce two groups of n output currents and one group of 2n output currents (n being even or odd) with equal amplitude and equal-phase space. The circuit only uses one multi-output current differencing transconductance amplifier and one grounded capacitor for each section, and is easy to integrate. Its oscillation condition and frequency can be electronically tuned linearly and independently, and its outputs possess high impedance. It is important that the multi-frequency oscillation in the oscillator is studied and a method for eliminating unnecessary oscillation is given. In addition, the inverting amplifier with the automatic gain control is employed to reduce the distortion of output signals. Finally, the frequency error is analysed and the simulated results are illustrated. © 2012 Copyright Taylor and Francis Group, LLC. Source


Li Y.,Xianyang Normal University
AEU - International Journal of Electronics and Communications | Year: 2012

This paper presents a new current-mode Wien-bridge oscillator with automatic amplitude control. The oscillator only employs single MCCCDTA as the active element and provides two current outputs with small distortion from high output impedances. Its oscillation condition and frequency can be tuned electronically, linearly and independently through tuning bias currents of MCCCDTA. The circuit simulation results are in agreement with theory. © 2011 Elsevier GmbH All rights reserved. Source


Li Y.A.,Xianyang Normal University
Analog Integrated Circuits and Signal Processing | Year: 2015

This paper presents a nodal admittance matrix expansion method for systematically synthesizing floating gyrators using current controlled current conveyor transconductance amplifiers (CCCCTAs). After describing nullor–mirror models of the CCCCTAs, class I and II gyrators are synthesized by means of NAM expansion method. The class I gyrators employing a CCCCTA and a current-controlled current conveyor have 16 equivalent realizations, and the class II gyrators employing two CCCCTAs have 24 equivalent realizations. Having used canonic number of components, the circuits are easy to be integrated and their parameters can be electronically tuned through tuning bias currents of CCCCTAs. Finally, as an example, the MULTISIM simulation results of a notch filter constructed by using a class II gyrator are presented to verify the realizability of the derived circuits. © 2014, Springer Science+Business Media New York. Source


Li Y.,Xianyang Normal University
Radioengineering | Year: 2010

This paper presents a modified current differencing transconductance amplifier (MCDTA) and a MCDTA based quadrature oscillator. The oscillator is current-mode and provides current output from high output impedance terminals. The circuit uses only one MCDTA and two grounded capacitors, and is easy to be integrated. Its oscillation frequency can be tuned electronically by tuning bias currents of MCDTA. Finally, frequency error is analyzed. The results of circuit simulations are in agreement with theory. Source

Discover hidden collaborations