Pseudo-resistor control circuit and pseudo-resistor providing device

Abstract

A pseudo-resistor control circuit and a pseudo-resistor providing device. The pseudo-resistor control circuit comprises a threshold voltage control module (10) and an adjustment module (20). An input end of the threshold voltage control module (10) is used for inputting a reference voltage (Vref). A control end of the threshold voltage control module (10) is connected to a control voltage (Vctrl). The threshold voltage control module (10) is used for converting the control voltage (Vctrl) into a control current. An input end of the adjustment module (20) is connected to an output end of the threshold voltage control module (10). An output end of the adjustment module (20) is connected to a control end of a pseudo-resistor (30). A control end of the adjustment module (20) and a first end of the pseudo-resistor (30) are connected to a first input voltage (Va). A second end of the pseudo-resistor (30) is connected to a second input voltage (Vb). The adjustment module (20) is used for adjusting a potential of the control end of the pseudo-resistor (30) on the basis of the first input voltage (Va) and the control current, so that the resistance of the pseudo-resistor (30) changes with the first input voltage (Va) and the second input voltage (Vb). The pseudo-resistor control circuit having such design has a simple structure and involves low costs.

Description

Pseudo-resistance control circuit and pseudo-resistance providing device Technical Field

[0001] The present invention relates to the technical field of analog integrated circuit design, and in particular to a pseudo-resistance control circuit and a pseudo-resistance providing device. Background Art

[0002] When manufacturing resistors with ultra-large resistance values ​​(generally GΩ level) under MOS process conditions, a very large area is required. Therefore, in order to reduce the chip area required to implement ultra-large resistors, inventors skilled in the art use MOS transistors to implement pseudo-resistors with ultra-large resistance values, thereby replacing traditional resistors.

[0003] The resistance of a pseudo-resistor is typically adjusted by controlling the voltage at its control terminal. Because pseudo-resistors are susceptible to factors such as process, voltage, and temperature (PVT), the adjustable voltage range at the pseudo-resistor control terminal is very small (typically a few hundred microvolts). Conventional technology typically utilizes a digital-to-analog converter and peripheral circuitry to provide a gate voltage of a few hundred microvolts for the pseudo-resistor.

[0004] The existing pseudo-resistance control circuit is complex in design and has high cost. Summary of the Invention

[0005] The present invention provides a pseudo-resistance control circuit and a pseudo-resistance providing device, which have a simple circuit structure and low cost.

[0006] In a first aspect, an embodiment of the present invention provides a pseudo-resistor control circuit for controlling the resistance of the pseudo-resistor, comprising: a threshold voltage control module and an adjustment module; the input end of the threshold voltage control module is used to input a reference voltage, the control end of the threshold voltage control module is connected to the control voltage, and the threshold voltage control module is used to convert the control voltage into a control current; the input end of the adjustment module is connected to the output end of the threshold voltage control module, the output end of the adjustment module is connected to the control end of the pseudo-resistor, the control end of the adjustment module and the first end of the pseudo-resistor are used to connect to a first input voltage, the second end of the pseudo-resistor is used to connect to a second input voltage, and the adjustment module is used to adjust the control end potential of the pseudo-resistor according to the first input voltage and the control current, so that the resistance of the pseudo-resistor changes according to the first input voltage and the second input voltage.

[0007] The threshold voltage control module includes a first switch unit and a second switch unit; the control end of the first switch unit serves as the control end of the threshold voltage control module, the first end of the first switch unit serves as the input end of the threshold voltage control module, and the second end of the first switch unit is connected to the first end of the second switch unit; the control end of the second switch unit is connected to the control end of the first switch unit, and the second end of the second switch unit serves as the output end of the threshold voltage control module; wherein the ranges of the control voltages corresponding to the conduction of the first switch unit and the second switch unit partially overlap.

[0008] Optionally, the first switching unit includes a first transistor, the second switching unit includes a second transistor, the gate of the first transistor serves as the control end of the first switching unit, the first pole of the first transistor serves as the first end of the first switching unit, the second pole of the first transistor serves as the second end of the first switching unit, the gate of the second transistor serves as the control end of the second switching unit, the first pole of the second transistor serves as the first end of the second switching unit, and the second pole of the second transistor serves as the second end of the second switching unit; wherein, the channel types of the first transistor and the second transistor are different.

[0009] Optionally, the first transistor is a PMOS transistor, and the second transistor is an NMOS transistor.

[0010] Optionally, the adjustment module includes a current adjustment unit and a current-to-voltage unit; the first end of the current adjustment unit serves as the input end of the adjustment module, the control end of the current adjustment unit serves as the control end of the adjustment module, and the second end of the current adjustment unit serves as the output end of the adjustment module, and the current adjustment module is used to adjust the control current according to the first input voltage; the first end of the current-to-voltage unit is connected to the second end of the current adjustment unit, the control end of the current-to-voltage unit is connected to the first end of the current-to-voltage unit, the second end of the current-to-voltage unit is grounded, and the current-to-voltage unit is used to convert the adjusted control current into the voltage of the pseudo-resistance control end.

[0011] Optionally, the current adjustment unit includes a third transistor; the first electrode of the third transistor serves as the first end of the current adjustment unit, the second electrode of the third transistor serves as the second end of the current adjustment unit, and the gate of the third transistor serves as the control end of the current adjustment unit.

[0012] Optionally, the current-to-voltage unit includes a fourth transistor, the first electrode of the fourth transistor serves as the first end of the current-to-voltage unit, the second electrode of the fourth transistor serves as the second end of the current-to-voltage unit, and the gate of the fourth transistor serves as the control end of the current-to-voltage unit.

[0013] In a second aspect, an embodiment of the present invention provides a pseudo-resistance providing device, comprising a pseudo-resistance and the pseudo-resistance control circuit provided in the first aspect; the control end of the pseudo-resistance is connected to the output end of the pseudo-resistance control circuit, and the pseudo-resistance control circuit is used to control the resistance value of the pseudo-resistance.

[0014] Optionally, the pseudo resistor includes a fifth transistor; the gate of the fifth transistor serves as the control terminal of the pseudo resistor, the first electrode of the fifth transistor is connected to the first input voltage, and the second electrode of the fifth transistor is connected to the second input voltage.

[0015] The pseudo-resistance control circuit and pseudo-resistance providing device of the embodiment of the present invention include a threshold voltage control module, an adjustment module and an output module; the control voltage is converted into a control current by the threshold voltage control module; the control terminal potential of the pseudo-resistance is adjusted by the adjustment module according to the first input voltage and the control current, so that the resistance value of the pseudo-resistance changes according to the first input voltage and the second input voltage. In other words, the pseudo-resistance control circuit provided by the embodiment of the present invention converts the control voltage of a large voltage range into a control current by the threshold voltage control module, and then converts the control current into the voltage of the pseudo-resistance control terminal by the adjustment module, avoiding the use of a digital-to-analog converter and peripheral circuits, thereby simplifying the difficulty of the pseudo-resistance control circuit design and reducing the circuit cost. In other words, the present invention uses a simple and low-cost control circuit to change the voltage of the pseudo-resistance control terminal, thereby adjusting the resistance value of the pseudo-resistance.

[0016] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] FIG1 is a schematic structural diagram of a pseudo-resistance control circuit provided by an embodiment of the present invention;

[0019] FIG2 is a schematic structural diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention;

[0020] FIG3 is a schematic structural diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention;

[0021] FIG4 is a schematic structural diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention;

[0022] FIG5 is a schematic structural diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention;

[0023] FIG6 is a schematic structural diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention;

[0024] 7 is a schematic structural diagram of a pseudo-resistance providing device according to an embodiment of the present invention;

[0025] FIG8 is a diagram showing the relationship between a control voltage and a pseudo-resistance gate voltage provided by an embodiment of the present invention;

[0026] FIG9 is a partial enlarged view of FIG8;

[0027] 10 is a diagram showing the relationship between a control voltage and a pseudo-resistance value provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar items and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions.

[0030] FIG1 is a schematic diagram of a pseudo-resistance control circuit according to an embodiment of the present invention. The pseudo-resistance control circuit can be used to control the resistance of a pseudo-resistance. As shown in FIG1 , the pseudo-resistance control circuit includes a threshold voltage control module 10 and an adjustment module 20.

[0031] The input end of the threshold voltage control module 10 is used to input the reference voltage Vref, the control end of the threshold voltage control module 10 is connected to the control voltage Vctrl, and the threshold voltage control module 10 is used to convert the control voltage Vctrl into a control current; the input end of the adjustment module 20 is connected to the output end of the threshold voltage control module 10, and the output end of the adjustment module 20 is connected to the control end of the pseudo-resistor 30. The control end of the adjustment module 20 and the first end of the pseudo-resistor 30 are used to receive the first input voltage Va, and the second end of the pseudo-resistor 30 is used to receive the second input voltage Vb. The adjustment module 20 is used to adjust the control end potential of the pseudo-resistor 30 according to the first input voltage Va and the control current, so that the resistance value of the pseudo-resistor 30 changes according to the first input voltage Va and the second input voltage Vb.

[0032] Specifically, the reference voltage Vref provides a fixed voltage for the threshold voltage control module 10 . The threshold voltage control module 10 may have various circuit structures for converting a control voltage into a control current.

[0033] Adjustment module 20 may be any combinational logic unit or integrated circuit capable of converting the control current into the control voltage required for the pseudo-resistor. For example, adjustment module 20 may change its resistance based on the first input voltage Va, thereby adjusting the control current and converting the adjusted control current into a voltage at the pseudo-resistor control terminal.

[0034] Taking the circuit structure shown in FIG1 as an example, the specific working process of the pseudo-resistance control circuit provided in this embodiment is as follows:

[0035] According to the correspondence between the first input voltage Va and the second input voltage Vb and the control voltage Vctrl, the correspondence between the control voltage Vctrl and the voltage at the control end of the pseudo-resistor, and the correspondence between the voltage at the control end of the pseudo-resistor and the resistance value of the pseudo-resistor, when the first input voltage Va and the second input voltage Vb change, the corresponding control voltage Vctrl can be input, and the control voltage Vctrl is converted into a control current through the threshold voltage control module 10. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control end of the pseudo-resistor 30 changes, and the resistance value of the pseudo-resistor 30 can be changed.

[0036] The pseudo-resistance control circuit and pseudo-resistance providing device of the embodiment of the present invention include a threshold voltage control module, an adjustment module, and an output module; the threshold voltage control module converts the control voltage into a control current; the adjustment module adjusts the control terminal potential of the pseudo-resistance according to the first input voltage and the control current, so that the resistance value of the pseudo-resistance changes according to the first input voltage and the second input voltage. In other words, the pseudo-resistance control circuit provided by the embodiment of the present invention converts the control voltage of a large voltage range into a control current through the threshold voltage control module, and then converts the control current into the voltage of the pseudo-resistance control terminal through the adjustment module, avoiding the use of a digital-to-analog converter and peripheral circuits, thereby simplifying the difficulty of the pseudo-resistance control circuit design and reducing the circuit cost. In other words, the present invention uses a simple and low-cost pseudo-resistance control circuit to change the voltage of the pseudo-resistance control terminal, thereby adjusting the resistance value of the pseudo-resistance.

[0037] FIG2 is a schematic diagram of another pseudo-resistance control circuit according to an embodiment of the present invention. Based on the above embodiments, as shown in FIG2 , the threshold voltage control module 10 optionally includes a first switch unit 110 and a second switch unit 120 .

[0038] The control end of the first switch unit 110 serves as the control end of the threshold voltage control module 10, the first end of the first switch unit 110 serves as the input end of the threshold voltage control module 10, and the second end of the first switch unit 110 is connected to the first end of the second switch unit 120; the control end of the second switch unit 120 is connected to the control end of the first switch unit 110, and the second end of the second switch unit 120 serves as the output end of the threshold voltage control module 10.

[0039] The range of the control voltage Vctrl corresponding to the conduction of the first switch unit 110 and the second switch unit 120 partially overlaps. Conductive means that current simultaneously flows between the first and second terminals of the first switch unit 110 and the first and second terminals of the second switch unit 120. At this time, the first switch unit 110 and the second switch unit can operate in the linear region, the subthreshold region, or the saturation region. When the control voltage Vctrl is within the overlapping range, both the first transistor M1 and the second transistor M2 are turned on. As an optional implementation provided by this embodiment, Figure 3 is a structural schematic diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention. In combination with Figures 2 and 3, the first switch unit 110 includes a first transistor M1, and the second switch unit 120 includes a second transistor M2. The gate of the first transistor M1 serves as the control end of the first switch unit 110, the first pole of the first transistor M1 serves as the first end of the first switch unit 110, the second pole of the first transistor M1 serves as the second end of the first switch unit 110, the gate of the second transistor M2 serves as the control end of the second switch unit 120, the first pole of the second transistor M2 serves as the first end of the second switch unit 120, and the second pole of the second transistor M2 serves as the second end of the second switch unit 120.

[0040] The first transistor M1 and the second transistor M2 have different channel types. For example, when the first transistor M1 is a P-channel transistor, the second transistor M2 is an N-channel transistor; when the first transistor M1 is an N-channel transistor, the second transistor M2 is a P-channel transistor. Preferably, the first transistor M1 is a PMOS transistor and the second transistor M2 is an NMOS transistor. Figure 3 schematically illustrates the case where the first transistor M1 is a PMOS transistor and the second transistor M2 is an NMOS transistor.

[0041] 3 , the specific working process of the pseudo-resistance control circuit provided in this embodiment is as follows:

[0042] According to the correspondence between the first input voltage Va and the second input voltage Vb and the control voltage Vctrl, the correspondence between the control voltage Vctrl and the voltage at the control end of the pseudo-resistor, and the correspondence between the voltage at the control end of the pseudo-resistor and the resistance value of the pseudo-resistor, when the first input voltage Va and the second input voltage Vb change, the corresponding control voltage Vctrl can be input, and the control voltage Vctrl is converted into a control current through the threshold voltage control module 10. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control end of the pseudo-resistor 30 changes, and the resistance value of the pseudo-resistor 30 can be changed.

[0043] The absolute value of the threshold voltage of the first transistor M1 is a first threshold voltage, and the absolute value of the threshold voltage of the second transistor M2 is a second threshold voltage. The pseudo resistor 30 may be an NMOS transistor.

[0044] Since the control current of the transistor in the subthreshold region is smaller than the control current in the linear region, the overall state of the first transistor M1 and the second transistor M2 can be divided into four working intervals:

[0045] First working range: When the control voltage Vctrl is 0V, the first transistor M1 enters the linear region (i.e., the variable resistance region), the second transistor M2 is turned off, no current flows through the adjustment module 10, and the voltage at the control end of the pseudo resistor 30 is 0. At this time, the equivalent resistance of the pseudo resistor 30 is very large.

[0046] In the second working interval, the control voltage Vctrl slowly increases from zero. When the difference between the reference voltage Vref and the control voltage is less than and close to the first threshold voltage, and the control voltage Vctrl is less than the second threshold voltage, the first transistor M1 enters the subthreshold region, and the second transistor M2 enters the subthreshold region. At this time, the adjustment module 20 receives a weak current, the voltage at the control end of the pseudo resistor 30 is greater than 0, and the equivalent resistance of the pseudo resistor 30 begins to decrease.

[0047] Third operating range: When the control voltage Vctrl increases to be greater than the second threshold voltage, the first transistor M1 is still in the subthreshold region, and the second transistor M2 enters the linear region. At this time, the current flowing through the adjustment module 20 is greater than the current when the first transistor M1 and the second transistor M2 operate in the second operating range, and the equivalent resistance of the pseudo resistor 30 drops to a minimum value.

[0048] Fourth working interval: When the control voltage Vctrl increases to close to the reference voltage Vref, the first transistor M1 is turned off, the second transistor M2 enters the linear region, no current flows through the adjustment module 10, and the voltage at the control end of the pseudo resistor 30 is 0. At this time, the equivalent resistance of the pseudo resistor 30 becomes the maximum value again.

[0049] FIG4 is a schematic diagram of the structure of another pseudo-resistance control circuit provided by an embodiment of the present invention. As shown in FIG4 , based on the above technical solutions, the adjustment module 20 optionally includes a current adjustment unit 210 and a current-to-voltage conversion unit 220 .

[0050] The first end of the current adjustment unit 210 serves as the input end of the adjustment module 20, the control end of the current adjustment unit 210 serves as the control end of the adjustment module 20, and the second end of the current adjustment unit 210 serves as the output end of the adjustment module 20. The current adjustment module 210 is used to adjust the control current according to the first input voltage Va.

[0051] Optionally, the current adjustment unit 210 can be a variable resistor, and the resistance of the variable resistor first increases and then decreases as the control voltage Vctrl increases. For example, when the pseudo-resistor 30 is an NMOS tube, the current adjustment unit 210 is used to ensure that the pseudo-resistor 30 can still provide a certain resistance value when the control current suddenly increases, to prevent the pseudo-resistor 30 from being turned on when the control current suddenly increases, so that the equivalent resistance value of the pseudo-resistor 30 is very small. Similarly, when the pseudo-resistor 30 is a PMOS tube, the current adjustment unit 210 is used to ensure that the pseudo-resistor 30 can still provide a certain resistance value when the control current suddenly decreases, to prevent the pseudo-resistor 30 from being turned on when the control current suddenly decreases, so that the equivalent resistance value of the pseudo-resistor is very small.

[0052] The first end of the current-to-voltage unit 220 is connected to the second end of the current adjustment unit 210. The control end of the current-to-voltage unit 220 is connected to the first end of the current-to-voltage unit 220. The second end of the current-to-voltage unit 220 is grounded. The current-to-voltage unit 220 is configured to convert the adjusted control current into a voltage at the control end of the pseudo-resistor 30. The current-to-voltage unit 220 can be any module or circuit structure having a current-to-voltage conversion function.

[0053] As an optional implementation provided by this embodiment, Figure 5 is a structural schematic diagram of another pseudo-resistance control circuit provided by an embodiment of the present invention. In combination with Figures 4 and 5, the current adjustment unit 210 includes a third transistor M3; the first electrode of the third transistor M3 serves as the first end of the current adjustment unit 210, the second electrode of the third transistor M3 serves as the second end of the current adjustment unit 210, and the gate of the third transistor M3 serves as the control end of the current adjustment unit 210.

[0054] The current-to-voltage unit 220 includes a fourth transistor M4, a first electrode of the fourth transistor M4 serves as a first end of the current-to-voltage unit 220, a second electrode of the fourth transistor M4 serves as a second end of the current-to-voltage unit 220, and a gate of the fourth transistor M4 serves as a control end of the current-to-voltage unit 220.

[0055] Figure 6 is a schematic diagram of the structure of another pseudo-resistance control circuit provided by an embodiment of the present invention. As shown in Figure 6, based on the above technical solutions, the pseudo-resistance control circuit includes: a threshold voltage control module 10 and an adjustment module 20. The threshold voltage control module 10 includes a first switch unit 110 and a second switch unit 120; the first switch unit 110 includes a first transistor M1, and the second switch unit 120 includes a second transistor M2; the adjustment module 20 includes a current adjustment unit 210 and a current-to-voltage conversion unit 220; the current adjustment unit 210 includes a third transistor M3; and the current-to-voltage conversion unit 220 includes a fourth transistor M4.

[0056] 6 , the specific working process of the pseudo-resistance control circuit provided in this embodiment is as follows:

[0057] According to the correspondence between the first input voltage Va and the second input voltage Vb and the control voltage Vctrl, the correspondence between the control voltage Vctrl and the voltage at the control end of the pseudo-resistor, and the correspondence between the voltage at the control end of the pseudo-resistor and the resistance value of the pseudo-resistor, when the first input voltage Va and the second input voltage Vb change, the corresponding control voltage Vctrl can be input, and the control voltage Vctrl is converted into a control current through the threshold voltage control module 10. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control end of the pseudo-resistor 30 changes, and the resistance value of the pseudo-resistor 30 can be changed.

[0058] The absolute value of the threshold voltage of the first transistor M1 is a first threshold voltage, and the absolute value of the threshold voltage of the second transistor M2 is a second threshold voltage. The pseudo resistor 30 may be an NMOS transistor.

[0059] Since the control current of the transistor in the subthreshold region is smaller than the control current in the linear region, the overall state of the first transistor M1 and the second transistor M2 can be divided into four working intervals:

[0060] First working interval: When the control voltage Vctrl is 0V, the first transistor M1 enters the linear region (i.e., the variable resistance region), the second transistor M2 is turned off, no current flows through the third transistor M3, the fourth transistor M4 is turned off, and the voltage at the control end of the pseudo resistor 30 is 0. At this time, the equivalent resistance of the pseudo resistor 30 is the largest.

[0061] Second operating range: When the control voltage Vctrl slowly increases from zero, when the difference between the reference voltage Vref and the control voltage Vctrl is less than and close to the first threshold voltage, and the control voltage Vctrl is less than the second threshold voltage, the first transistor M1 enters the subthreshold region, the second transistor M2 enters the subthreshold region, and the channel equivalent resistance of the third transistor M3 increases as the control current increases. The fourth transistor M4 receives a weak control current, causing the fourth transistor M4 to also operate in the subthreshold region. At this time, the drain-source voltage of the fourth transistor M4 is logarithmically related to the control current. This drain-source voltage directly controls the voltage at the control end of the pseudo-resistor 30, making the equivalent resistance of the pseudo-resistor 30 adjustable.

[0062] Third operating range: When the control voltage Vctrl increases to be greater than the second threshold voltage, the first transistor M1 is still in the subthreshold region, and the second transistor M2 enters the linear region. At this time, the current flowing through the adjustment module 20 is greater than the current when the first transistor M1 and the second transistor M2 operate in the second operating range, and the equivalent resistance of the pseudo resistor 30 drops to a minimum value.

[0063] Fourth operating range: When the control voltage Vctrl increases to a value close to the reference voltage Vref, the first transistor M1 turns off, the second transistor M2 enters the linear region, no current flows through the third transistor M3, and the fourth transistor M4 turns off. The voltage at the control terminal of the pseudo-resistor 30 is 0, and the equivalent resistance of the pseudo-resistor 30 returns to its maximum value. Throughout this process, the equivalent resistance of the pseudo-resistor 30 changes from large to small and then to large again. The equivalent resistance of the third transistor M3 also changes from large to small and then to large again.

[0064] In summary, due to the different carrier velocities of the first transistor M1 (e.g., a PMOS transistor) and the second transistor M2 (an NMOS transistor), the control current can be adjusted across the operating range of the transistors by adjusting the control voltage Vctrl, thereby obtaining the desired pseudo-resistor value. Furthermore, the cascade connection of the first transistor M1 and the second transistor M2 determines that the control range of the first transistor M1 and the second transistor M2 is clamped within these three operating ranges, thereby avoiding the situation where the pseudo-resistor fails due to excessive control current caused by overshoot voltage.

[0065] It should be noted that the reference voltage Vref can be set as needed. For example, to prevent the first transistor M1 and the second transistor M2 from entering the saturation region, the reference voltage Vref can be set to be relatively low. For example, when the absolute value of the threshold voltage of the first transistor M1 and the threshold voltage of the second transistor M2 are both 0.7V, the reference voltage Vref can be set to 1.2V.

[0066] Optionally, an embodiment of the present invention further provides a pseudo-resistance providing device, which includes a pseudo-resistance and the pseudo-resistance control circuit of any of the above embodiments, and has corresponding functional modules and beneficial effects of the pseudo-resistance control circuit.

[0067] Figure 7 is a structural schematic diagram of a pseudo-resistance providing device provided by an embodiment of the present invention. Optionally, the pseudo-resistance 30 includes a fifth transistor M5; the gate of the fifth transistor M5 serves as the control end of the pseudo-resistance 30, the first electrode of the fifth transistor M5 is connected to the first input voltage Va, and the second electrode of the fifth transistor M5 is connected to the second input voltage Vb.

[0068] In a standard 180nm CMOS process, the relationship between the control voltage and the gate voltage of the controlled pseudo-resistor can be obtained. Figure 8 is a diagram showing the relationship between the control voltage and the gate voltage of the pseudo-resistor, provided by an embodiment of the present invention. Referring to Figure 8 , the horizontal axis represents the control voltage Vctrl, in V; the vertical axis represents the gate voltage of the fifth transistor M5 (i.e., gate voltage VG), in mV. It can be seen that as the control voltage Vctrl increases from 0V to 1.2V, the gate voltage of the pseudo-resistor first increases and then decreases. Figure 9 is a partially enlarged view of Figure 8 . Referring to Figure 9 , the horizontal axis represents the control voltage Vctrl, in V; the vertical axis represents the gate voltage of the fifth transistor M5 (i.e., gate voltage), in μV.

[0069] Figure 10 is a graph showing the relationship between control voltage and pseudo-resistor resistance, according to an embodiment of the present invention. As shown in Figure 10 , the horizontal axis represents the control voltage Vctrl (V), and the vertical axis represents the pseudo-resistor resistance R (GΩ). Combining Figures 8 and 10 , as the control voltage Vctrl increases from 0V to 1.2V, the gate voltage of the pseudo-resistor first increases and then decreases, while the pseudo-resistor resistance decreases and then increases again.

[0070] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A pseudo-resistance control circuit for controlling the resistance value of a pseudo-resistance, characterized in that: include: Threshold voltage control module and adjustment module; The input terminal of the threshold voltage control module is used to input a reference voltage, the control terminal of the threshold voltage control module is connected to a control voltage, and the threshold voltage control module is used to convert the control voltage into a control current; The input end of the adjustment module is connected to the output end of the threshold voltage control module, and the output end of the adjustment module is connected to the control end of the pseudo-resistor. The control end of the adjustment module and the first end of the pseudo-resistor are used to access a first input voltage, and the second end of the pseudo-resistor is used to access a second input voltage. The adjustment module is used to adjust the potential of the control end of the pseudo-resistor according to the first input voltage and the control current, so that the resistance value of the pseudo-resistor changes according to the first input voltage and the second input voltage.

2. The pseudo-resistance control circuit according to claim 1, characterized in that: The threshold voltage control module includes a first switch unit and a second switch unit; The control end of the first switch unit serves as the control end of the threshold voltage control module, the first end of the first switch unit serves as the input end of the threshold voltage control module, and the second end of the first switch unit is connected to the first end of the second switch unit; The control end of the second switch unit is connected to the control end of the first switch unit, and the second end of the second switch unit serves as the output end of the threshold voltage control module; The ranges of the control voltages corresponding to the conduction of the first switch unit and the second switch unit partially overlap.

3. The pseudo-resistance control circuit according to claim 2, characterized in that: The first switch unit includes a first transistor, the second switch unit includes a second transistor, the gate of the first transistor serves as a control end of the first switch unit, the first electrode of the first transistor serves as a first end of the first switch unit, the second electrode of the first transistor serves as a second end of the first switch unit, the gate of the second transistor serves as a control end of the second switch unit, the first electrode of the second transistor serves as a first end of the second switch unit, and the second electrode of the second transistor serves as a second end of the second switch unit; The first transistor and the second transistor have different channel types.

4. The pseudo-resistance control circuit according to claim 3, characterized in that: The first transistor is a PMOS transistor, and the second transistor is an NMOS transistor.

5. The pseudo-resistance control circuit according to claim 1, characterized in that: The adjustment module includes a current adjustment unit and a current-to-voltage conversion unit; The first end of the current adjustment unit serves as the input end of the adjustment module, the control end of the current adjustment unit serves as the control end of the adjustment module, the second end of the current adjustment unit serves as the output end of the adjustment module, and the current adjustment module is used to adjust the control current according to the first input voltage; The first end of the current-to-voltage unit is connected to the second end of the current adjustment unit, the control end of the current-to-voltage unit is connected to the first end of the current-to-voltage unit, the second end of the current-to-voltage unit is grounded, and the current-to-voltage unit is used to convert the adjusted control current into the voltage of the pseudo-resistance control end.

6. The pseudo-resistance control circuit according to claim 5, characterized in that: The current adjustment unit includes a third transistor; The first electrode of the third transistor serves as the first end of the current adjustment unit, the second electrode of the third transistor serves as the second end of the current adjustment unit, and the gate of the third transistor serves as the control end of the current adjustment unit.

7. The pseudo-resistance control circuit according to claim 5, characterized in that: The current-to-voltage unit includes a fourth transistor, a first electrode of the fourth transistor serves as a first end of the current-to-voltage unit, a second electrode of the fourth transistor serves as a second end of the current-to-voltage unit, and a gate of the fourth transistor serves as a control end of the current-to-voltage unit.

8. A pseudo-resistance providing device, characterized in that: A pseudo-resistor comprising a pseudo-resistor and a pseudo-resistance control circuit according to any one of claims 1 to 7; The control end of the pseudo resistor is connected to the output end of the pseudo resistor control circuit, and the pseudo resistor control circuit is used to control the resistance value of the pseudo resistor.

9. The pseudo-resistance providing device according to claim 8, characterized in that: The pseudo resistor comprises a fifth transistor; The gate of the fifth transistor serves as the control terminal of the pseudo resistor, the first electrode of the fifth transistor is connected to the first input voltage, and the second electrode of the fifth transistor is connected to the second input voltage.

Images