Memristor-based threshold voltage continuous adjustable current-adjusting circuit

Abstract

The invention discloses a threshold voltage continuously-adjustable throttling circuit based on a memristor. The threshold voltage continuously-adjustable throttling circuit comprises a single chip microcomputer, a rectifying circuit, a memristor regulation and control circuit and an upper computer Uart serial port communication circuit. The method comprises the following steps: firstly, receiving a specific threshold voltage input by an upper computer through a Uart serial port by a single chip microcomputer, and calculating a required memristor resistance value by the single chip microcomputer; secondly, the singlechip regulates and controls a PMOS (P-channel Metal Oxide Semiconductor) tube of a phase inverter in the rectifying circuit, and closes a power supply, so that the rectifying circuit stops working; then, the single-chip microcomputer controls the memristor regulation and control circuit to work, after the resistance value of the memristor reaches a preset value, the single-chip microcomputer controls the memristor regulation and control circuit to stop working, the resistance value of the memristor is fixed, meanwhile, the single-chip microcomputer recovers a PMOS tube power supply of a phase inverter in the rectification circuit, and the rectification circuit continues to rectify the input signal; and finally, an output signal is returned to the single-chip microcomputer for detection and is used for closed-loop monitoring of a rectification signal, and more accurate threshold voltage continuous adjustability is realized.

Description

Technical Field

[0001] The present invention relates to a rectifier circuit with continuously adjustable threshold voltage, and particularly to a rectifier circuit with continuously adjustable threshold voltage based on a memristor. Background Art

[0002] The main function of a rectifier circuit is to convert an input signal into a stable and reliable output signal. In the field of analog circuits, a rectifier circuit can be used for signal denoising, processing a noisy input signal into a pure output signal; in the field of digital circuits, a rectifier circuit can be used to design a pulse signal generator to generate specific pulse signals; in industrial electrical equipment, a rectifier circuit converts alternating current into direct current to provide a stable DC power supply for a DC motor; in an automatic control system, a rectifier circuit can also be used for parameter monitoring, and when a preset parameter exceeds its threshold range, an alarm signal can be triggered. Therefore, rectifier circuits have broad application potential in various system fields.

[0003] Traditional rectifier circuits usually adopt a Schmitt trigger circuit, such as Figure 1 shown. It consists of resistors R1 - R2, PMOS transistors Q1, Q3, and NMOS transistors Q2, Q4, and its working principle is to convert the input signal based on the hysteresis characteristic of the Schmitt trigger circuit. The input signal V in is connected to the first - stage inverter composed of resistor R1, PMOS transistor Q1, and NMOS transistor Q2; PMOS transistor Q3 and NMOS transistor Q4 form the second - stage inverter and are connected to the output signal V out ; resistor R2 is connected across the output terminal of the second - stage inverter and the input terminal of the first - stage inverter.

[0004] In Figure 1 the rectifier circuit, after the signal is input, by comparing the magnitude of the input signal voltage with the forward or reverse threshold voltage of the rectifier circuit, the final output voltage is determined. When the power supply voltage V DD of the inverter is greater than the sum of the threshold voltages V th of the PMOS transistor and the NMOS transistor, according to Kirchhoff's current law, the input voltage V A of the first - stage inverter can be expressed as: . When the input voltage V A of the inverter is greater than the threshold voltage V th of the MOS transistor, the output signal V out is at a high level, and vice versa, the output signal V out is at a low level; that is, when the input voltage V in is greater than , the output voltage V out flips to a high level; when the input voltage V in is lower than When, the output voltage V out flips to a low level. Under the action of the rectifying circuit, the input signal can be rectified and a corresponding square wave signal can be generated. The forward or reverse threshold voltage during rectification can be jointly determined by adjusting the resistors R1, R2 in the rectifying circuit and the power supply V of the inverter. DD to jointly determine.

[0005] Traditional rectifying circuits usually use adjustable resistors, such as linear potentiometers or multi-turn potentiometers, to adjust the forward or reverse threshold voltage in the rectifying circuit by changing the resistance value in the rectifying circuit; however, linear potentiometers have disadvantages such as mechanical wear, non-linearity problems, and low precision, and multi-turn potentiometers have disadvantages such as high cost, large volume, and low durability.

[0006] Currently, the memristor is the fourth basic electronic component in addition to resistors, inductors, and capacitors. The memristor has resistance plasticity, and its resistance value can change according to the voltage applied to the memristor and remains unchanged after power-off; the resistance plasticity of the memristor has directionality, that is, applying opposite voltages can cause opposite changes in the resistance value; at the same time, the voltage threshold type memristor is characterized in that the resistance value of the memristor only changes when the voltage across its two ends exceeds the threshold. In addition, the memristor also has advantages such as high speed, nano-size, low power consumption, high reliability, CMOS compatibility, and easy large-scale integration. Therefore, the memristor is suitable for application in hardware circuit design and can preferably replace adjustable resistor components such as linear potentiometers or multi-turn potentiometers.

[0007] Based on the resistance plasticity and threshold characteristics of the memristor, the present invention proposes a threshold voltage continuously adjustable rectifying circuit based on the memristor, which realizes continuous controllability of the threshold voltage of the rectifying circuit and also meets the design requirements of high precision, small size, low power consumption, and high speed. Summary of the Invention

[0008] The present invention proposes a threshold voltage continuously adjustable rectifying circuit based on the memristor, which uses a voltage threshold type memristor to replace the potentiometer in the traditional rectifying circuit and uses a single-chip microcomputer to control the memristor regulation circuit to realize continuous adjustability of the resistance value of the memristor, so that the forward or reverse threshold voltage when the rectifying circuit processes the input signal can be continuously adjustable.

[0009] The present invention is realized through the following technical solutions: A threshold voltage continuously adjustable rectifying circuit based on the memristor, which includes a single-chip microcomputer, a rectifying circuit, a memristor regulation circuit, and a host computer Uart serial port communication circuit.

[0010] First, the single-chip microcomputer can receive the specific threshold voltage input by the host computer through the serial port, and calculate the required resistance value of the memristor. Secondly, the single-chip microcomputer controls the PMOS transistor of the inverter in the rectifier circuit, turns off its power supply, and stops the rectifier circuit from working. Then, the single-chip microcomputer controls the memristor regulation circuit to work. After the resistance value of the memristor reaches the preset value, the single-chip microcomputer controls the memristor regulation circuit to stop working, fixes the resistance value of the memristor, and at the same time the single-chip microcomputer restores the power supply of the PMOS transistor of the inverter in the rectifier circuit, so that the rectifier circuit continues to rectify the input signal. Finally, the output signal can be returned to the single-chip microcomputer for detection, realizing the closed-loop monitoring of the rectified signal and achieving more precise continuously adjustable threshold voltage.

[0011] The rectifier circuit is composed of a memristor M1, a resistor R1, PMOS transistors Q1, Q3, NMOS transistors Q2, Q4, and works based on the hysteresis principle of the circuit. PMOS transistor Q1 and NMOS transistor Q2 form the first-stage inverter, and PMOS transistor Q3 and NMOS transistor Q4 form the second-stage inverter. The sources of Q1 and Q3 are connected to the P1.5 pin of the single-chip microcomputer in parallel, and the single-chip microcomputer controls the power supply of the PMOS transistor of the inverter through the P1.5 pin. When the rectifier circuit works normally, the voltage value across the memristor M1 is lower than its threshold voltage, making the resistance value of the memristor fixed. M1, R1 that make up the rectifier circuit and the power supply of the inverter are used to regulate the forward or reverse threshold voltage during the rectification process. According to Kirchhoff's current law, the input voltage V of the first-stage inverter A can be expressed as: . When the input voltage V in is greater than , the output voltage V out flips to a high level; when the input voltage V in is lower than , the output voltage V out flips to a low level. Under the action of the rectifier circuit, the input signal can be rectified and a corresponding square wave signal can be generated. The threshold voltage during the rectification of the input signal can be jointly determined by the memristor M1, the resistor R1 and the power supply V of the inverter in the rectifier circuit DD . By changing the resistance value of the memristor M1, the forward or reverse threshold voltage of the rectifier circuit can be changed.

[0012] The memristor regulation circuit consists of a positive power supply V CC , a negative power supply V EE and multiple NMOS transistors Q5 - Q7, and is used to adjust the resistance value of the memristor M1. The single-chip microcomputer adjusts the on-state of the NMOS transistor connected to it by controlling the level of the output pin. The positive power supply V CC and the negative power supply V EEThe positive electrode of the memristor is connected in parallel through NMOS transistors Q5 and Q6, while the negative electrode of the memristor M1 is grounded through the NMOS transistor Q7. When the microcontroller controls the NMOS transistor Q5 connected to V CC and the NMOS transistor Q7 connected to the negative electrode of the memristor to conduct, the positive voltage of the memristor will exceed the positive threshold voltage, resulting in a decrease in the resistance value of the memristor; conversely, when the microcontroller controls the NMOS transistor Q6 connected to V EE and the NMOS transistor Q7 connected to the negative electrode of the memristor to conduct, the positive voltage of the memristor will exceed the negative threshold voltage, causing the resistance value of the memristor to increase. By adjusting the conduction time of the NMOS transistor and the magnitude of the applied voltage, the microcontroller can effectively control and adjust the resistance value of the memristor.

[0013] The square wave signal output by the rectifier circuit can be returned to the microcontroller through the feedback loop. The microcontroller compares the input signal with the output signal to obtain the accurate threshold magnitude, realizing precise adjustment and closed-loop monitoring. Description of the Drawings

[0014] Figure 1 is a traditional rectifier circuit diagram.

[0015] Figure 2 is a threshold voltage continuously adjustable rectifier circuit based on a memristor in the present invention.

[0016] Figure 3 is a variation diagram of the resistance value of the memristor M1 in the present invention.

[0017] Figure 4 is a comparison diagram of the output signal and the input signal in the present invention. Detailed Embodiment

[0018] To make the technical solutions, objectives, and advantages of the present invention clearer and more definite, the following further details the specific implementation process of the present invention in conjunction with the drawings.

[0019] As Figure 2 shown, the present invention proposes a threshold voltage continuously adjustable rectifier circuit based on a memristor, which includes a microcontroller, a rectifier circuit, a memristor regulation circuit, and a host computer Uart serial communication circuit.

[0020] As Figure 2 shown, the microcontroller uses a 51 series microcontroller with Uart function. The GND pin of the microcontroller is grounded, and the V CCThe pin is connected to a 5V voltage source. The P1.0 pin of the single-chip microcomputer is connected to the initial input signal. The P1.1 pin of the single-chip microcomputer is connected to the gate of the NMOS transistor Q5. The P1.2 pin of the single-chip microcomputer is connected to the gate of the NMOS transistor Q6. The P1.3 pin of the single-chip microcomputer is connected to the gate of the NMOS transistor Q7. The P1.5 pin of the single-chip microcomputer is connected to the sources of the PMOS transistors Q1 and Q3. The P1.4 pin of the single-chip microcomputer is connected to the output signal of the rectifier circuit.

[0021] As Figure 2 shown, the rectifier circuit is composed of a memristor M1, a resistor R1, PMOS transistors Q1 and Q3, and NMOS transistors Q2 and Q4. The positive pole of the memristor M1 is connected to the input terminal P1.0. The negative pole of the memristor M1 is connected to the gates of the PMOS transistor Q1 and the NMOS transistor Q2. One end of the resistor R1 is connected to the drains of the PMOS transistor Q3 and the NMOS transistor Q4, and the other end of the resistor R1 is connected to the gates of the PMOS transistor Q1 and the NMOS transistor Q2. After the drains of Q1 and Q2 are connected in parallel, they serve as the output port of the first-stage inverter and are connected to the gates of Q3 and Q4. The drains of the PMOS transistor Q3 and the NMOS transistor Q4 are connected together and serve as the output port of the rectifier circuit. The sources of the NMOS transistors Q2 and Q4 are grounded.

[0022] As Figure 2 shown, the memristor regulation circuit consists of a positive power supply V CC , a negative power supply V EE and NMOS transistors Q5-Q7. The sources of the NMOS transistors Q5 and Q6 are connected in parallel to the positive pole of the memristor M1. The drains of Q5 and Q6 are respectively connected to the voltage source V CC and the voltage source V EE . The source of the NMOS transistor Q7 is grounded, and the drain of Q7 is connected to the negative pole of the memristor M1.

[0023] As Figure 2 shown, the host computer and the single-chip microcomputer are connected through the Uart serial port. The host computer inputs the reference threshold voltage of the rectifier circuit into the single-chip microcomputer, and the single-chip microcomputer calculates the resistance value of the memristor corresponding to the reference threshold voltage through an internal program.

[0024] In the present invention, the forward or reverse threshold voltage of the rectifier circuit is jointly determined by M1, R1, and the power supply of the inverter. The calculation formulas for its forward threshold voltage V ut and reverse threshold voltage V lt can be respectively expressed as: and .

[0025] Taking Figure 2Taking the simulation verification of the shown circuit as an example, set the initial resistance value of the memristor M1 in the circuit to 10 kΩ, the resistance value of the resistor R1 to 20 kΩ, and the supply voltage of the PMOS transistors Q1 and Q3 in the rectifier circuit to 200 mV. The circuit simulation process is as follows. Assume that the rectifier circuit starts working at 0 ms, and then a sinusoidal signal with an amplitude of 100 mV, a frequency of 200 Hz, and a DC level of 100 mV is input. At 25 ms, the power supply of the inverter in the rectifier circuit is disconnected, and the rectifier circuit stops working. Then the microcontroller controls the memristor regulation circuit to start working. At 25 ms, the resistance value of the memristor M1 starts to change, and at 36.75 ms, the resistance value of the memristor M1 stops changing. At the same time, the power supply of the inverter in the rectifier circuit is restored, and then the rectifier circuit outputs a square wave signal with a different threshold value.

[0026] As Figure 3 shown, the initial resistance value of the memristor M1 is 10 kΩ, and it changes during the period from 25 ms to 36.75 ms, with the resistance value changing from 10 kΩ to 1 kΩ. The resistance value of the memristor M1 remains unchanged at other times.

[0027] As Figure 4 shown, during the period from 0 ms to 25 ms, the initial resistance value of the memristor M1 remains unchanged, and the rectifier circuit works normally. During this period, by comparing the input sinusoidal wave and the output square wave values, it can be known that the forward threshold voltage is 150 mV and the reverse threshold voltage is 50 mV. During the period from 25 ms to 36.75 ms, the rectifier circuit stops working and there is no output signal, while the memristor regulation circuit works and the resistance value of the memristor M1 changes. The rectifier circuit starts working again at 36.75 ms, and at the same time the memristor regulation circuit stops working, and the resistance value of the memristor M1 stops changing. By comparing the input sinusoidal wave and the output square wave values, the forward threshold voltage is 105 mV and the reverse threshold voltage is 95 mV at this time. It can be seen that before and after the resistance value of the memristor M1 changes, the values of the forward threshold voltage and the reverse threshold voltage of the rectifier circuit are consistent with the results calculated by the formula in

[0024] .

Claims

1. A memristor-based threshold voltage continuously adjustable current circuit, characterized in that, It includes a single-chip microcomputer, a rectifier circuit, a memristor regulation circuit, and a host computer Uart serial communication circuit; among them, the single-chip microcomputer first receives the specific threshold voltage input by the host computer through the Uart serial port, and calculates the required memristor resistance value by the single-chip microcomputer; secondly, the single-chip microcomputer regulates the PMOS transistor of the inverter in the rectifier circuit, turns off its power supply, and makes the rectifier circuit stop working; then, the single-chip microcomputer controls the memristor regulation circuit to work. After the resistance value of the memristor reaches the preset value, the single-chip microcomputer controls the memristor regulation circuit to stop working, makes the memristor resistance value fixed, and at the same time the single-chip microcomputer restores the power supply of the PMOS transistor of the inverter in the rectifier circuit, so that the rectifier circuit continues to rectify the input signal; finally, the output signal is returned to the single-chip microcomputer for detection, which is used for the closed-loop monitoring of the rectified signal and realizes the continuous adjustment of the more accurate threshold voltage. The single-chip microcomputer uses a 51 series single-chip microcomputer with Uart function. The GND pin of the single-chip microcomputer is grounded, and the V CC pin of the single-chip microcomputer is connected to a 5V voltage source. The P1.0 pin of the single-chip microcomputer is connected to the initial input signal. The P1.1 pin of the single-chip microcomputer is connected to the gate of NMOS transistor Q5. The P1.2 pin of the single-chip microcomputer is connected to the gate of NMOS transistor Q6. The P1.3 pin of the single-chip microcomputer is connected to the gate of NMOS transistor Q7. The P1.5 pin of the single-chip microcomputer is connected to the sources of PMOS transistors Q1 and Q3. The P1.4 pin of the single-chip microcomputer is connected to the output signal of the rectifier circuit; The rectifier circuit is composed of a memristor M1, a resistor R1, PMOS transistors Q1, Q3, NMOS transistors Q2, Q4; the positive pole of the memristor M1 is connected to the input terminal P1.0, and the negative pole of the memristor M1 is connected to the gates of the PMOS transistor Q1 and the NMOS transistor Q2; one end of the resistor R1 is connected to the drains of the PMOS transistor Q3 and the NMOS transistor Q4, and the other end of the resistor R1 is connected to the gates of the PMOS transistor Q1 and the NMOS transistor Q2; the drains of Q1 and Q2 are connected in parallel and then used as the output port of the first-stage inverter and connected to the gates of Q3 and Q4; the drains of the PMOS transistor Q3 and the NMOS transistor Q4 are connected together and used as the output port of the rectifier circuit; the sources of the NMOS transistors Q2 and Q4 are grounded. The memristor control circuit consists of a positive power supply V CC , a negative power supply V EE and NMOS transistors Q5 - Q7; the sources of NMOS transistors Q5 and Q6 are connected in parallel to the positive pole of the memristor M1, and the drains of Q5 and Q6 are respectively connected to the voltage source V CC and the voltage source V EE ; the source of NMOS transistor Q7 is grounded, and the drain of Q7 is connected to the negative pole of the memristor M1; The host computer and the single-chip microcomputer are connected through the Uart serial port. The host computer inputs the reference threshold voltage of the rectifier circuit into the single-chip microcomputer, and the single-chip microcomputer calculates the memristor resistance value corresponding to the reference threshold voltage through the internal program.

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