scholarly journals Electronic Circuit with Controllable Negative Differential Resistance and its Applications

Electronics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 409 ◽  
Author(s):  
Vladimir Ulansky ◽  
Ahmed Raza ◽  
Hamza Oun

Electronic devices and circuits with negative differential resistance (NDR) are widely used in oscillators, memory devices, frequency multipliers, mixers, etc. Such devices and circuits usually have an N-, S-, or Λ-type current-voltage characteristics. In the known NDR devices and circuits, it is practically impossible to increase the negative resistance without changing the type or the dimensions of transistors. Moreover, some of them have three terminals assuming two power supplies. In this paper, a new NDR circuit that comprises a combination of a field effect transistor (FET) and a simple bipolar junction transistor (BJT) current mirror (CM) with multiple outputs is proposed. A distinctive feature of the proposed circuit is the ability to change the magnitude of the NDR by increasing the number of outputs in the CM. Mathematical expressions are derived to calculate the threshold currents and voltages of the N-type current-voltage characteristics for various types of FET. The calculated current and voltage thresholds are compared with the simulation results. The possible applications of the proposed NDR circuit for designing single-frequency oscillators and voltage-controlled oscillators (VCO) are considered. The designed NDR VCO has a very low level of phase noise and has one of the best values of a standard figure of merit (FOM) among recently published VCOs. The effectiveness of the proposed oscillators is confirmed by the simulation results and the implemented prototype.

Author(s):  
С.О. Слипченко ◽  
А.А. Подоскин ◽  
О.С. Соболева ◽  
В.С. Юферев ◽  
В.С. Головин ◽  
...  

AbstractThe current–voltage characteristics of n ^+-GaAs/ n ^0-GaAs/ N ^0-AlGaAs/ N ^+-AlGaAs/ n ^+-GaAs isotype heterostructures and n ^+-GaAs/ n ^0-GaAs/ n ^+-GaAs homostructures are studied. It is shown that, for a heterostructure under reverse bias providing the injection of electrons from n ^0-GaAs into N ^0-AlGaAs, the maximum operating voltage reaches a value of 48 V at a thickness of the N ^0-AlGaAs layer of 1 . 0 μm, and the current–voltage characteristic has no region of negative differential resistance. The operation of a homostructure is accompanied by a transition to the negative-differential-resistance region at a voltage of 10 V. Theoretical analysis in terms of the energy-balance model demonstrated that the reverse-biased isotype heterostructure has no negative-differential-resistance region because, in this case, the field domain does not collapse in contrast to what occurs in homostructures.


2021 ◽  
Author(s):  
Denice Feria ◽  
Sonia Sharma ◽  
Yu-Ting Chen ◽  
Zhi-Ying Weng ◽  
Kuo-Pin Chiu ◽  
...  

Abstract Understanding the mechanism of the negative differential resistance (NDR) in transition metal dichalcogenides is essential for fundamental science and the development of electronic devices. Here, the NDR of the current-voltage characteristics was observed based on the glutamine-functionalized WS2 quantum dots (QDs). The NDR effect can be adjusted by varying the applied voltage range, air pressure, surrounding gases, and relative humidity. A peak-to-valley current ratio as high as 6.3 has been achieved at room temperature. Carrier trapping induced by water molecules was suggested to be responsible for the mechanism of the NDR in the glutamine-functionalized WS2 QDs. Investigating the NDR of WS2 QDs may promote the development of memory applications and emerging devices.


2021 ◽  
Vol 67 ◽  
pp. 25-31
Author(s):  
Sophia R. Figarova ◽  
Elvin M. Aliyev ◽  
Rashad G. Abaszade ◽  
R.I. Alekberov ◽  
Vagif R. Figarov

Graphene oxide/sulphur compound was synthesized by Hammers method. The chemical composition, presence/quantity of functional groups, exfoliation level, number of layers, crystallite size of graphene oxide/sulphur were characterized by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy images. The current-voltage characteristics of the samples were measured in air at room temperature. In the I - V characteristic curve of graphene oxide/sulphur compound with the ratio of oxygen to carbon of 3.54 and that to sulphur of 42.54, negative differential resistance was observed. The negative differential resistance is attributed to current carrier transitions between the localized states formed by functional groups.


2012 ◽  
Vol 624 ◽  
pp. 162-165
Author(s):  
C.Q. Huang ◽  
X.B. Liu ◽  
X.A. Mei ◽  
J. Liu

The electrical properties of Er2O3-doped bismuth titanate,Bi4-xErxTi3O12 (BET) ceramics prepared by a conventional electroceramic technique were investigated. XRD analyses revealed Bi-layered perovskite structure in all samples. SEM micrographs showed randomly oriented and plate-like morphology. For the samples with x=0.4 and 1.0 the current-voltage characteristics exhibited negative differential resistance behaviors and their P-E hysteresis loops were characterized by large leakage current, whereas for the samples with x=0.6 and 0.8 the current-voltage characteristics showed simple ohmic behaviors and their P-E hysteresis loops were the saturated and undistorted hysteresis loops. The remanent polarization ( Pr ) and coercive field (Ec) of the BET ceramic with x=0.8 were above 20μC/cm2 and 65KV/cm , respectively.


2021 ◽  
Vol 11 (21) ◽  
pp. 9815
Author(s):  
Vladimir Ulansky ◽  
Ahmed Raza ◽  
Denys Milke

Negative differential resistance (NDR) is inherent in many electronic devices, in which, over a specific voltage range, the current decreases with increasing voltage. Semiconductor structures with NDR have several unique properties that stimulate the search for technological and circuitry solutions in developing new semiconductor devices and circuits experiencing NDR features. This study considers two-terminal NDR electronic circuits based on multiple-output current mirrors, such as cascode, Wilson, and improved Wilson, combined with a field-effect transistor. The undoubted advantages of the proposed electronic circuits are the linearity of the current-voltage characteristics in the NDR region and the ability to regulate the value of negative resistance by changing the number of mirrored current sources. We derive equations for each proposed circuit to calculate the NDR region’s total current and differential resistance. We consider applications of NDR circuits for designing microwave single frequency oscillators and voltage-controlled oscillators. The problem of choosing the optimal oscillator topology is examined. We show that the designed oscillators based on NDR circuits with Wilson and improved Wilson multiple-output current mirrors have high efficiency and extremely low phase noise. For a single frequency oscillator consuming 33.9 mW, the phase noise is −154.6 dBc/Hz at a 100 kHz offset from a 1.310 GHz carrier. The resulting figure of merit is −221.6 dBc/Hz. The implemented oscillator prototype confirms the theoretical achievements.


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