CN203206207U - Double-end active equivalent circuit of load-control memristor - Google Patents

Abstract

The utility model discloses a double-end active equivalent circuit of a load-control memristor. The double-end active equivalent circuit comprises a resistor R1, a resistor R2, a resistor R3, a first voltage follower, a second voltage follower, a first subtracter a first summator, a second subtracter, a second summator, a third subtracter, an integrator, a divider, a fourth subtracter and a voltage source Uref. The double-end active equivalent circuit controls a current flowing though an active memristor through feedback, adopts the resistor R1, the resistor R2 and the resistor R3 which are serially connected for voltage division, and controls currents flowing though the R1 and the R3 by adding feedback between the R1 and a R2, as well as between the R2 and R3; and the feedback is realized through an arithmetic circuit according to a U-I feature of the memristor, so that the feedback is in accordance with the electrical properties of the memristor. Since the double-end active equivalent circuit is not realized by controlling a variable resistor, the double-end active equivalent circuit has the advantages of high precision, explicit double ends and clear mathematical concept, can be connected to the circuit and used in parallel or in series with other components, and is a practical active memristor.

Description

The active equivalent electric circuit of a kind of both-end of lotus control memristor

Technical field

The utility model relates to a kind of essential electronic element, is specifically related to the active equivalent electric circuit of a kind of both-end of lotus control memristor.

Background technology

The few Chinese bush cherry of Objective Concept Cai of memristor (Memristor) proposed in 1971, gain the name in its resistance to the dependence by electric weight, be considered to the 4th basic circuit elements outside resistance, electric capacity and the inductance.To characteristic time memory of resistance it is had broad application prospects in model analysis, tandem circuit design, circuit devcie design with to the various fields such as emulation of organic memory behavior.

Owing to lacking the support of experiment, between after being suggested twenties years of memristor, though correlation theory has development not cause enough concerns.

A kind of nanometer both-end resistance with memory function had been found in the HP laboratory in 2008, and its electrical characteristic conforms to the memristor characteristic of Cai Shaotang prediction, thereby had confirmed the existence of memristor.

The memristor that the HP laboratory is found is a kind of nanoscale components and parts, manufactures relatively difficulty, also almost can't buy in the market this components and parts.Therefore, the method for studying at present this memristor is to mainly contain: 1. build active memristor, namely by FEEDBACK CONTROL variable resistor (such as photo resistance, digital regulation resistance), make variable resistor present the electrical characteristic of memristor.The shortcoming of this research method is the electrical characteristic that variable-resistance shortcoming can restrict memristor, and affected by environment large such as photo resistance, the change in resistance of digital regulation resistance is not continuous.2. set up simulation model.The shortcoming of this research method is that the variable resistor in the simulation model is Utopian, can only realize in emulation, may realize in actual experiment hardly.3. realize the electrical characteristic of memristor by logical circuit, computing circuit.From present document, this active memristor does not have clear and definite both-end definition, namely can not be equivalent to the both-end element in the accessible circuit fully, such as connecting with other element.

The utility model content

The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art, and a kind of equivalent electric circuit of active memristor is provided.The utility model does not use variable resistor, thereby overcome the impact that variable-resistance shortcoming causes active memristor, simultaneously, circuit structure of the present utility model, clear and definite both-end definition and mathematical concept are arranged, easily in experiment, realize, can be used as the characteristic research of active memristor and directly use as the memristor components and parts.

For realizing above purpose, the technical scheme that the utility model has been taked is:

The active equivalent electric circuit of a kind of both-end of lotus control memristor, it comprises: resistance R 1, resistance R 2, resistance R 3, the first voltage follower, second voltage follower, the first subtracter, first adder, the second subtracter, second adder, the 3rd subtracter, multiplication factor are integrator, divider, the 4th subtracter and the voltage source U of K _Ref

Described resistance R 1, resistance R 2, resistance R 3 are connected successively, and the two ends of resistance R 1 are labeled as respectively side a and b, and the two ends of resistance R 3 are labeled as respectively C end and D end, and wherein the B end is the common port of resistance R 1 and resistance R 2, and the C end is the common port of resistance R 3 and resistance R 2;

Described A end is connected in the input of second voltage follower, and described D end is connected in the input of the first voltage follower; The positive input terminal of the first subtracter is connected to the output of the first voltage follower, and the negative input end of the first subtracter is connected to the output of second voltage follower; The negative input end of described the 3rd subtracter is connected in the output of second voltage follower, and its positive input terminal is connected to the B end; The input of described integrator is connected to the output of the 3rd subtracter; The positive and negative input of described the 4th subtracter is connected to voltage source U _RefThe output of output sum-product intergrator; The molecule input of described divider is connected to the output of the first subtracter, and its denominator input is connected to the output of the 4th subtracter; One input of described second adder is connected to the output of second voltage follower, and another input is connected to the output of divider, and its output is connected to the B end; The positive and negative input of the second subtracter is connected to respectively the output of the first subtracter and the output of divider; One input of described first adder is connected to the output of second voltage follower, and its another input is connected to the output of the second subtracter, and its output is connected to the C end.

The resistance of described resistance R 3 and resistance R 1 equates.

The method that the utility model is realized is the electric current that flows through active memristor by FEEDBACK CONTROL, resistance R 1, R2, the R3 dividing potential drop of 3 series connection have been used, add feedback between resistance R 1 and the resistance R 2 and control the electric current that flows through resistance R 1, add feedback between resistance R 2 and the resistance R 3 and control the electric current that flows through resistance R 3, add voltage follower simultaneously so that flow through the electric current I of resistance R 1, R3 ₁, I ₃Flow through exactly the electric current at memristor two ends.Feedback is the U-I characteristic according to memristor, realizes by computing circuit, makes it meet the electrical characteristic of memristor.

The utility model compared with prior art has following advantage: 1. do not realize by the control variable resistor, be not subjected to the impact of variable-resistance shortcoming, control precision is high; 2. not only can realize in emulation, and also can realize in actual experiment, be a kind of practicable active memristor; 3. both-end is clear and definite, and mathematical concept is clear, uses with other element serial or parallel connection in the accessible circuit.

Description of drawings

Fig. 1 is the structured flowchart of the active equivalent electric circuit embodiment of a kind of both-end of the utility model lotus control memristor;

Fig. 2 a is the passive memristor that the HP laboratory is found;

Fig. 2 b is the equivalent electric circuit of active memristor among the embodiment of Fig. 1;

Fig. 3 is a kind of realization circuit theory diagrams of the embodiment of Fig. 1;

Fig. 4 is when Fig. 3 circuit is carried out emulation, after the two ends of active memristor apply sine wave, and the U-I characteristic curve of this active memristor;

The figure that oscilloscope is seen in Fig. 5 actual experiment.

Wherein: 2, voltage follower; 3, voltage follower; 4, subtracter; 5, adder; 6, subtracter; 7, adder; 8, subtracter; 9, integrator; 10, divider; 11, subtracter.

Embodiment

Below in conjunction with the drawings and specific embodiments content of the present utility model is described in further details.

Embodiment:

Please refer to Fig. 1, the active equivalent electric circuit of a kind of both-end of lotus control memristor, this equivalence circuit comprise that resistance R 1, resistance R 2, resistance R 3, voltage follower 2, voltage follower 3, subtracter 4, adder 5, subtracter 6, adder 7, subtracter 8, multiplication factor are integrator 9, divider 10, subtracter 11 and the voltage source U of K _RefDescribed resistance R 1, resistance R 2, resistance R 3 are connected successively, the two ends of resistance R 1 are labeled as respectively side a and b, the two ends of resistance R 3 are labeled as respectively C end and D end, wherein the B end is the common port of resistance R 1 and resistance R 2, the C end is the common port of resistance R 3 and resistance R 2, and D end and A end have represented respectively two ports (being respectively M end and N end) of the active memristor of equivalence.The A end is connected in the input of voltage follower 3, and the D end is connected in the input of voltage follower 2; The positive input terminal of subtracter 4 is connected to the output of voltage follower 2, and the negative input end of subtracter 4 is connected to the output of voltage follower 3; The negative input end of described subtracter 8 is connected in the output of voltage follower 3, and its positive input terminal is connected to the B end; The input of described integrator 9 is connected to the output of subtracter 8; The positive and negative input of described subtracter 11 is connected to voltage source U _RefThe output of output sum-product intergrator 9; The molecule input of described divider 10 is connected to the output of subtracter 4, and its denominator input is connected to the output of subtracter 11; One input of described adder 7 is connected to the output of voltage follower 3, and another input is connected to the output of divider 10, and its output is connected to the B end; The positive and negative input of subtracter 6 is connected to respectively the output of subtracter 4 and the output of divider 10; One input of described adder 5 is connected to the output of voltage follower 3, and its another input is connected to the output of subtracter 6, and its output is connected to the C end.

The voltage that we define the A end is U _A, the voltage of B end is U _B, the voltage of C end is U _C, the voltage of D end is U _D, the voltage at M, N two ends is U _i, the voltage of B end and A end is U ₁, the voltage of D end and C end is U ₃, the voltage of D end and A end is identical with the voltage at M, N two ends also to be U _i, voltage source U _RefOutput voltage be U _Ref, so the output voltage=U of subtracter 8 _B-U _A=U ₁, the output voltage=U of subtracter 4 _D-U _A=U _i

By calculating as can be known: the output voltage of integrator 9=K ∫ U ₁Dt(K is the multiplication factor of integrator 9), the output voltage=U of subtracter 11 _Ref-K ∫ U ₁Dt,

In above-mentioned formula

Can push away to get the electric current of the resistance R 1 of flowing through

$i_1=\frac{U_B-U_A}{R_1}=\frac{U_i}{U_{\mathrm{ref}}{R}_1-{\mathrm{KR}}_1{\∫U}_1\mathrm{dt}}=\frac{U_i}{U_{\mathrm{ref}}{R}_1-{\mathrm{KR}}_1{R}_1\∫\frac{U_1}{R_1}\mathrm{dt}}=\frac{U_i}{U_{\mathrm{ref}}{R}_1-{\mathrm{KR}}_1{R}_1\∫i_1\mathrm{dt}}---\left(1\right)$

Following formula (1) is the U-I characteristic of the active memristor of the utility model.

In conjunction with Fig. 2 a, the electronics mobile behavior of passive memristor inside is complicated, and the HP laboratory is derived at R after it is simplified _ON＜＜R _OFFThe resistance M of memristor with the pass of the electric charge q that flows through is under the condition:

$M=R_{\mathrm{OFF}}-\frac{{{\mathrm{\μ}}_{v}R}_{\mathrm{ON}}{R}_{\mathrm{OFF}}}{D^2}q---\left(2\right)$

Wherein, R _ONAnd R _OFFRepresent respectively doped region and the resistance of doped region not, D is the material TiO of memristor ₂Total length, μ _vBe the migration rate of particle, these parameters depend on material therefor, and when material has determined, these parameters have also just determined, can be considered constant.So can make E=R _OFF,

So (2) but the relation abbreviation of resistance M and q is M=E – Fq in the formula, obviously resistance M is determined by electric charge q, so the passive memristor that the HP laboratory is found is a kind of lotus control memristor.

Its U-I closes $i=\frac{U}{M}=\frac{U}{E-\mathrm{Fq}}=\frac{U}{E-F\∫\mathrm{idt}}---\left(3\right)$

Formula (1) formula and formula (3) above the contrast are as long as the formula of order (1) U _RefR ₁=E, KR ₁R ₁=F can satisfy the U-I relation of memristor, at this moment the i in (1) formula ₁Satisfy the U-I relation of memristor.

Voltage follower plays buffer action, so that flow through the current i of resistance R 1 ₁Equal to flow through the current i of this active memristor N end _N, i.e. i _N=i ₁So current i of N end _NSatisfy the U-I relation of memristor.

At the other end M of active memristor end, for resistance R 3, because U _i=U _D– U _A, i.e. U _D=U _i+ U _A, C end feedback so that

So both end voltage of R3 $U_{}$ ${}_3=U_D$

$-U_C=\frac{U_i}{U_{\mathrm{ref}}-K\∫U_1\mathrm{dt}}.$

As seen, when the both end voltage of resistance R 3 equates with the both end voltage of resistance R 1, even R ₃=R ₁, i is then arranged ₃=i ₁(i in the formula ₃Be the electric current of the resistance R 3 of flowing through).Under the effect of voltage follower, i is arranged _M=i ₃, i.e. i _M=i ₃=i ₁=i _NSo current i of M end _MSatisfy the U-I relation of memristor.

The electric current at two ends that is the equivalent electric circuit of active memristor all satisfies the U-I relation of memristor, and the electric current that flows through two ends equates, these electric currents that equate represent that with i i=i is then arranged _M=i ₃=i ₁=i _N

The active schematic equivalent circuit of both-end is shown in Fig. 2 a and Fig. 2 b.M end and N end in M end among Fig. 2 b and the N end difference corresponding diagram 1; Flow through the i=i in the current i corresponding diagram 1 that M holds and N holds among Fig. 2 b _M=i _NThe active memristor of Fig. 1 description just can represent with Fig. 2 b so, and the active memristor that obvious Fig. 2 b represents satisfies the U-I relation of memristor in the formula (3).Passive memristor among Fig. 2 a (memristor of finding such as the HP laboratory), its resistance M can represent with formula (2), and its U-I concerns and can represent with (3) formula.Definition by resistance

As can be known, if the U-I relation of the voltage between two ports and the electric current that flows through these two ports is definite, its equivalent resistance has also just been determined so.If the respectively corresponding M end of X end and Y end and N end, Fig. 2 a has identical U-I relation with Fig. 2 b so, that is to say that Fig. 2 b is a kind of equivalent electric circuit of Fig. 2 a.

Fig. 3 is the circuit of the realization of building according to the theory diagram of the utility model Fig. 1.Wherein, the voltage follower 2 in amplifier U11 and the peripheral circuit corresponding diagram 1 thereof, the voltage follower 3 in amplifier U12 and the peripheral circuit corresponding diagram 1 thereof, U _RefVoltage source U in the corresponding diagram 1 _RefSubtracter 4 in amplifier U14 and the peripheral circuit corresponding diagram 1 thereof, subtracter 6 in amplifier U15 and the peripheral circuit corresponding diagram 1 thereof and the combination of adder 5, subtracter 8 in amplifier U16 and the peripheral circuit corresponding diagram 1 thereof, integrator 9 in amplifier U17 and the peripheral circuit corresponding diagram 1 thereof, subtracter 11 in amplifier U18 and the peripheral circuit corresponding diagram 1 thereof, the adder 7 in amplifier U19 and the peripheral circuit corresponding diagram 1 thereof, and do not describing in detail here for the annexation of circuit.

In each resistance value among Fig. 3 and the integrator 9 capacitance of capacitor C can be as required the passive memristor of equivalence adjust; In the present embodiment, each amplifier all can realize with chips such as LM741CN; Divider can form by the multiplier such as AD633JN and amplifier, also can be with special divider chip.The supply power voltage that each chip needs depends on the voltage that puts on active memristor two ends, and the voltage at two ends that puts on active memristor is higher, and the supply power voltage that chip needs is just higher.The output voltage of integrator will have ceiling restriction, and this point can realize by limiting its supply power voltage.The initial resistance of the equivalence of this active memristor depends on the initial voltage at the capacitor C two ends in the integrator.

When Fig. 3 circuit is carried out emulation, take ± 12V to chip power supply (wherein the supply power voltage of integrator as ± 4V), the initial voltage of capacitor C is-4V, it is 4V that the two ends of this active memristor are applied an amplitude, frequency is the sine wave of 1Hz, obtains its U-I characteristic curve as shown in Figure 4.Also can see by oscilloscope in the experiment, see Fig. 5.By Fig. 4 and Fig. 5 as seen, its U-I relation meets the electrical characteristic of memristor.

Above-listed detailed description is that this embodiment limits claim of the present utility model for the specifying of the utility model possible embodiments, and does not allly break away from the equivalence that the utility model does and implements or change, all should be contained in the claim of this case.

Claims (2)

1. the active equivalent electric circuit of a kind of both-end of lotus control memristor, it is characterized in that, it comprises: resistance R 1, resistance R 2, resistance R 3, the first voltage follower (2), second voltage follower (3), the first subtracter (4), first adder (5), the second subtracter (6), second adder (7), the 3rd subtracter (8), multiplication factor are integrator (9), divider (10), the 4th subtracter (11) and the voltage source U of K _Ref

Described resistance R 1, resistance R 2, resistance R 3 are connected successively, and the two ends of resistance R 1 are labeled as respectively side a and b, and the two ends of resistance R 3 are labeled as respectively C end and D end, and wherein the B end is the common port of resistance R 1 and resistance R 2, and the C end is the common port of resistance R 3 and resistance R 2;

Described A end is connected in the input of second voltage follower (3), and described D end is connected in the input of the first voltage follower (2); The positive input terminal of the first subtracter (4) is connected to the output of the first voltage follower (2), and the negative input end of the first subtracter (4) is connected to the output of second voltage follower (3); The negative input end of described the 3rd subtracter (8) is connected in the output of second voltage follower (3), and its positive input terminal is connected to the B end; The input of described integrator (9) is connected to the output of the 3rd subtracter (8); The positive and negative input of described the 4th subtracter (11) is connected to voltage source U _RefThe output of output sum-product intergrator (9); The molecule input of described divider (10) is connected to the output of the first subtracter (4), and its denominator input is connected to the output of the 4th subtracter (11); One input of described second adder (7) is connected to the output of second voltage follower (3), and another input is connected to the output of divider (10), and its output is connected to the B end; The positive and negative input of the second subtracter (6) is connected to respectively the output of the first subtracter (4) and the output of divider (10); One input of described first adder (5) is connected to the output of second voltage follower (3), and its another input is connected to the output of the second subtracter (6), and its output is connected to the C end.

2. the active equivalent electric circuit of a kind of both-end of lotus control memristor according to claim 1 is characterized in that, the resistance of described resistance R 3 and resistance R 1 equates.

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