A pseudo-resistance control circuit and a pseudo-resistance providing device

Abstract

The application discloses a pseudo-resistance control circuit and a pseudo-resistance providing device, and the pseudo-resistance control circuit comprises a threshold voltage control module and an adjusting module; an input end of the threshold voltage control module is used for inputting a reference voltage, a control end of the threshold voltage control module is connected with a control voltage, and the threshold voltage control module is used for converting the control voltage into a control current; an input end of the adjusting module is connected with an output end of the threshold voltage control module, an output end of the adjusting module is connected with a control end of the pseudo-resistance, a control end of the adjusting module and a first end of the pseudo-resistance are used for connecting with a first input voltage, a second end of the pseudo-resistance is used for connecting with a second input voltage, and the adjusting module is used for adjusting the control end potential of the pseudo-resistance according to the first input voltage and the control current, so that the resistance of the pseudo-resistance changes according to the first input voltage and the second input voltage. The pseudo-resistance control circuit disclosed by the application has simple structure and low cost.

Description

Technical Field

[0001] This invention relates to the field of analog integrated circuit design technology, and in particular to a pseudo-resistor control circuit and a pseudo-resistor providing device. Background Technology

[0002] When fabricating resistors with extremely large resistance values ​​(typically in the GΩ range) using processes such as MOS, a very large area is required. Therefore, in order to reduce the chip area required to realize extremely large resistors, inventors skilled in the art use MOS transistors to realize pseudo-resistors with extremely large resistance values, thereby replacing traditional resistors.

[0003] The resistance value of a pseudo-resistor is typically adjusted by controlling the voltage at its control terminal. Because pseudo-resistors are highly susceptible to factors such as process, voltage, and temperature (PVT), the adjustable range of the voltage at the pseudo-resistor control terminal is very small (typically a few hundred microvolts). Current technologies generally utilize digital-to-analog converters and external circuitry to provide a gate voltage of a few hundred microvolts to the pseudo-resistor.

[0004] Existing pseudo-resistor control circuit designs are complex and costly. Summary of the Invention

[0005] This 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, embodiments of the present invention provide a pseudo-resistor control circuit for controlling the resistance value of a pseudo-resistor, comprising: a threshold voltage control module and an 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 terminal of the adjustment module is connected to the output terminal of the threshold voltage control module, the output terminal of the adjustment module is connected to the control terminal of the pseudo-resistor, the control terminal of the adjustment module and a first terminal of the pseudo-resistor are used to input a first input voltage, the second terminal of the pseudo-resistor is used to input a second input voltage, and the adjustment module is used to adjust the potential of the control terminal 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.

[0007] The threshold voltage control module includes a first switching unit and a second switching unit; the control terminal of the first switching unit serves as the control terminal of the threshold voltage control module, the first terminal of the first switching unit serves as the input terminal of the threshold voltage control module, and the second terminal of the first switching unit is connected to the first terminal of the second switching unit; the control terminal of the second switching unit is connected to the control terminal of the first switching unit, and the second terminal of the second switching unit serves as the output terminal of the threshold voltage control module; wherein, the range of the control voltage corresponding to the conduction of the first switching unit and the second switching unit partially overlaps.

[0008] Optionally, the first switching unit includes a first transistor, and the second switching unit includes a second transistor. The gate of the first transistor serves as the control terminal of the first switching unit, the first electrode of the first transistor serves as the first terminal of the first switching unit, the second electrode of the first transistor serves as the second terminal of the first switching unit, and the gate of the second transistor serves as the control terminal of the second switching unit. The first electrode of the second transistor serves as the first terminal of the second switching unit, and the second electrode of the second transistor serves as the second terminal of the second switching unit. The first transistor and the second transistor have different channel types.

[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 conversion unit; the first terminal of the current adjustment unit serves as the input terminal of the adjustment module, the control terminal of the current adjustment unit serves as the control terminal of the adjustment module, and the second terminal of the current adjustment unit serves as the output terminal of the adjustment module. The current adjustment module is used to adjust the control current according to the first input voltage; the first terminal of the current-to-voltage conversion unit is connected to the second terminal of the current adjustment unit, the control terminal of the current-to-voltage conversion unit is connected to the first terminal of the current-to-voltage conversion unit, and the second terminal of the current-to-voltage conversion unit is grounded. The current-to-voltage conversion unit is used to convert the adjusted control current into the voltage of the pseudo-resistor control terminal.

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

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

[0013] Secondly, embodiments of the present invention provide a pseudo resistor providing device, including a pseudo resistor and a pseudo resistor control circuit provided in the first aspect; the control terminal of the pseudo resistor is connected to the output terminal of the pseudo resistor control circuit, and the pseudo resistor control circuit is used to control the resistance value of the pseudo resistor.

[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 terminal of the fifth transistor is connected to a first input voltage, and the second terminal of the fifth transistor is connected to a second input voltage.

[0015] The pseudo-resistor control circuit and pseudo-resistor providing device of this invention include a threshold voltage control module, an adjustment module, and an output module. The threshold voltage control module converts a control voltage into a control current. The adjustment module adjusts the potential of the control terminal of the pseudo-resistor according to a first input voltage and a control current, so that the resistance value of the pseudo-resistor changes according to the first and second input voltages. In other words, the pseudo-resistor control circuit provided by this invention converts a control voltage over a wide voltage range into a control current through the threshold voltage control module, and then converts the control current into a voltage at the control terminal of the pseudo-resistor through the adjustment module. This avoids the use of a digital-to-analog converter and peripheral circuits, thereby simplifying the design of the pseudo-resistor control circuit and reducing circuit costs. In other words, this invention uses a simple, low-cost control circuit to change the voltage at the control terminal of the pseudo-resistor, thereby adjusting the resistance value of the pseudo-resistor.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a pseudo-resistor control circuit provided in an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention;

[0021] Figure 4This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the structure of a pseudo-resistance providing device provided in an embodiment of the present invention;

[0025] Figure 8 This is a diagram showing the relationship between control voltage and pseudo-resistor gate voltage provided in an embodiment of the present invention;

[0026] Figure 9 yes Figure 8 A magnified view of a portion of the image;

[0027] Figure 10 This is a diagram showing the relationship between control voltage and pseudo-resistance value provided in an embodiment of the present invention; Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0030] Figure 1 This is a schematic diagram of a pseudo-resistor control circuit provided in an embodiment of the present invention. This pseudo-resistor control circuit can be used to control the resistance value of the pseudo-resistor. For example... Figure 1 As shown, the pseudo-resistance control circuit includes a threshold voltage control module 10 and an adjustment module 20.

[0031] The input terminal of the threshold voltage control module 10 is used to input the reference voltage Vref, and the control terminal of the threshold voltage control module 10 is connected to the control voltage Vctrl. The threshold voltage control module 10 is used to convert the control voltage Vctrl into a control current. The input terminal of the adjustment module 20 is connected to the output terminal of the threshold voltage control module 10, and the output terminal of the adjustment module 20 is connected to the control terminal of the pseudo resistor 30. The control terminal of the adjustment module 20 and the first terminal of the pseudo resistor 30 are used to connect to the first input voltage Va, and the second terminal of the pseudo resistor 30 is used to connect to the second input voltage Vb. The adjustment module 20 is used to adjust the potential of the control terminal 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, which can be a circuit structure that converts the control voltage into a control current.

[0033] The adjustment module 20 can be any combinational logic unit or integrated circuit that converts the control current into the control voltage required for the pseudo-resistance. For example, the adjustment module 20 can change its own resistance value according to the first input voltage Va, thereby adjusting the control current and converting the adjusted control current into the voltage at the pseudo-resistance control terminal.

[0034] by Figure 1 Taking the circuit structure shown as an example, the specific working process of the pseudo-resistor control circuit provided in this embodiment is as follows:

[0035] Based on 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 terminal of the pseudo resistor, and the correspondence between the voltage at the control terminal 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. The threshold voltage control module 10 converts the control voltage Vctrl into a control current. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control terminal of the pseudo resistor 30 changes, and the resistance value of the pseudo resistor 30 changes accordingly.

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

[0037] Figure 2 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention. This embodiment is based on the above embodiments, as follows... Figure 2 As shown, optionally, the threshold voltage control module 10 includes a first switching unit 110 and a second switching unit 120.

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

[0039] In this embodiment, the control voltage Vctrl corresponding to the conduction of the first switching unit 110 and the second switching unit 120 partially overlaps. Conduction means that current flows simultaneously between the first and second terminals of both the first and second switching units 110 and 120. At this time, the first and second switching units 110 and 120 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. This is an optional implementation provided in this embodiment. Figure 3 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention, combined with... Figure 2 and Figure 3The first switching unit 110 includes a first transistor M1, and the second switching unit 120 includes a second transistor M2. The gate of the first transistor M1 serves as the control terminal of the first switching unit 110, the first electrode of the first transistor M1 serves as the first terminal of the first switching unit 110, and the second electrode of the first transistor M1 serves as the second terminal of the first switching unit 110. The gate of the second transistor M2 serves as the control terminal of the second switching unit 120, the first electrode of the second transistor M2 serves as the first terminal of the second switching unit 120, and the second electrode of the second transistor M2 serves as the second terminal of the second switching 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 The illustration shows the case where the first transistor M1 is a PMOS transistor and the second transistor M2 is an NMOS transistor.

[0041] refer to Figure 3 The specific working process of the pseudo-resistor control circuit provided in this embodiment is as follows:

[0042] Based on 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 terminal of the pseudo resistor, and the correspondence between the voltage at the control terminal 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. The threshold voltage control module 10 converts the control voltage Vctrl into a control current. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control terminal of the pseudo resistor 30 changes, and the resistance value of the pseudo resistor 30 changes accordingly.

[0043] In this configuration, the absolute value of the threshold voltage of the first transistor M1 is the first threshold voltage, and the threshold voltage of the second transistor M2 is the second threshold voltage. The dummy resistor 30 can be an NMOS transistor.

[0044] Since the control current of the transistor in the subthreshold region is less 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 operating regions:

[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 20, the voltage at the control terminal of the pseudo resistor 30 is 0, and the equivalent resistance of the pseudo resistor 30 is very large at this time.

[0046] Second operating range: 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 terminal 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 a value 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 of the first transistor M1 and the second transistor M2 when they are operating in the second operating range, and the equivalent resistance of the pseudo resistor 30 drops to the minimum value.

[0048] Fourth operating range: When the control voltage Vctrl increases to near 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, the voltage at the control terminal of the pseudo resistor 30 is 0, and the equivalent resistance of the pseudo resistor 30 becomes the maximum value again.

[0049] Figure 4 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention. Figure 4 As shown, based on the above technical solutions, the adjustment module 20 may optionally include 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 unit 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, the resistance of which first increases and then decreases as the control voltage Vctrl increases. For example, when the dummy resistor 30 is an NMOS transistor, the current adjustment unit 210 ensures that the dummy resistor 30 still provides a certain resistance value when the control current suddenly increases, preventing the dummy resistor 30 from conducting and thus making its equivalent resistance very small. Similarly, when the dummy resistor 30 is a PMOS transistor, the current adjustment unit 210 ensures that the dummy resistor 30 still provides a certain resistance value when the control current suddenly decreases, preventing the dummy resistor 30 from conducting and thus making its equivalent resistance very small.

[0052] The first terminal of the current-to-voltage unit 220 is connected to the second terminal of the current adjustment unit 210. The control terminal of the current-to-voltage unit 220 is connected to the first terminal of the current-to-voltage unit 220, and the second terminal of the current-to-voltage unit 220 is grounded. The current-to-voltage unit 220 is used to convert the adjusted control current into the voltage of the control terminal of the pseudo-resistor 30. The current-to-voltage unit 220 can be any module or circuit structure with current-to-voltage conversion function.

[0053] As an optional implementation method provided in this embodiment, Figure 5 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention, combined with... Figure 4 and Figure 5 The current adjustment unit 210 includes a third transistor M3; the first terminal of the third transistor M3 serves as the first terminal of the current adjustment unit 210, the second terminal of the third transistor M3 serves as the second terminal of the current adjustment unit 210, and the gate of the third transistor M3 serves as the control terminal of the current adjustment unit 210.

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

[0055] Figure 6 This is a schematic diagram of another pseudo-resistor control circuit provided in an embodiment of the present invention. Figure 6As shown, 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 switching unit 110 and a second switching unit 120; the first switching unit 110 includes a first transistor M1, and the second switching 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] refer to Figure 6 The specific working process of the pseudo-resistor control circuit provided in this embodiment is as follows:

[0057] Based on 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 terminal of the pseudo resistor, and the correspondence between the voltage at the control terminal 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. The threshold voltage control module 10 converts the control voltage Vctrl into a control current. Since the control voltage Vctrl changes, the magnitude of the control current flowing through the adjustment module 20 changes, the voltage at the control terminal of the pseudo resistor 30 changes, and the resistance value of the pseudo resistor 30 changes accordingly.

[0058] In this configuration, the absolute value of the threshold voltage of the first transistor M1 is the first threshold voltage, and the threshold voltage of the second transistor M2 is the second threshold voltage. The dummy resistor 30 can be an NMOS transistor.

[0059] Since the control current of the transistor in the subthreshold region is less 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 operating regions:

[0060] First operating 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 third transistor M3, the fourth transistor M4 is turned off, the voltage at the control terminal of the pseudo resistor 30 is 0, and the equivalent resistance of the pseudo resistor 30 is at its maximum at this time.

[0061] Second operating range: When the control voltage Vctrl slowly increases from zero, and 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, the channel equivalent resistance of the third transistor M3 increases with the increase of the control current, and 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 terminal of the pseudo resistor 30, making the equivalent resistance value of the pseudo resistor 30 adjustable.

[0062] Third operating range: When the control voltage Vctrl increases to a value 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 of the first transistor M1 and the second transistor M2 when they are operating in the second operating range, and the equivalent resistance of the pseudo resistor 30 drops to the minimum value.

[0063] Fourth operating range: When the control voltage Vctrl increases to near 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, the fourth transistor M4 turns off, and the voltage at the control terminal of the pseudo resistor 30 is 0. At this time, the equivalent resistance of the pseudo resistor 30 becomes its maximum value again. Throughout the process, the equivalent resistance of the pseudo resistor 30 changes from large to small and then back to large, and the equivalent resistance of the third transistor M3 also changes from large to small and then back to large.

[0064] In summary, because the carrier velocities of the first transistor M1 (e.g., a PMOS transistor) and the second transistor M2 (an NMOS transistor) are different, the control current can be adjusted across the transistor's operating range by regulating the control voltage Vctrl, thereby obtaining the desired pseudo-resistance value. Furthermore, the cascading arrangement of the first transistor M1 and the second transistor M2 clamps their control ranges within these three operating ranges, thus preventing the pseudo-resistance from failing 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 small. For instance, 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, embodiments of the present invention also provide a pseudo resistor providing device, which includes a pseudo resistor and a pseudo resistor control circuit of any of the above embodiments, and has the corresponding functional modules and beneficial effects of the pseudo resistor control circuit.

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

[0068] Under standard 180nm CMOS technology, the relationship between the control voltage and the gate voltage of the controlled pseudo-resistor can be obtained. Figure 8 This is a diagram showing the relationship between control voltage and pseudo-resistance gate voltage provided in an embodiment of the present invention. (Refer to...) Figure 8 The horizontal axis represents the control voltage Vctrl, in V; the vertical axis represents the gate voltage (VG) of the fifth transistor M5, 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 yes Figure 8 A magnified view of the area, for reference. Figure 9 The horizontal axis represents the control voltage Vctrl, in V; the vertical axis represents the gate voltage (i.e., gate voltage) of the fifth transistor M5, in μV.

[0069] Figure 10 This is a diagram showing the relationship between control voltage and pseudo-resistance value provided in an embodiment of the present invention, such as... Figure 10 As shown, the horizontal axis represents the control voltage Vctrl, in volts (V); the vertical axis represents the resistance value R of the dummy resistor, in gigawatts (GΩ). Combined with... Figure 8 and Figure 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 resistance value of the pseudo resistor decreases and then increases again.

[0070] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A pseudo-resistance control circuit for controlling the resistance value of a pseudo-resistor, 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 terminal of the adjustment module is connected to the output terminal of the threshold voltage control module, and the output terminal of the adjustment module is connected to the control terminal of the pseudo resistor. The control terminal of the adjustment module and the first terminal of the pseudo resistor are used to connect to a first input voltage, and the second terminal of the pseudo resistor is used to connect to a second input voltage. The adjustment module is used to adjust the potential of the control terminal 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. The threshold voltage control module includes a first switching unit and a second switching unit; The control terminal of the first switching unit serves as the control terminal of the threshold voltage control module, the first terminal of the first switching unit serves as the input terminal of the threshold voltage control module, and the second terminal of the first switching unit is connected to the first terminal of the second switching unit. The control terminal of the second switching unit is connected to the control terminal of the first switching unit, and the second terminal of the second switching unit serves as the output terminal of the threshold voltage control module. Wherein, the ranges of the control voltages corresponding to the conduction of the first switching unit and the second switching unit partially overlap; The first switching unit includes a first transistor, and the second switching unit includes a second transistor. The gate of the first transistor serves as the control terminal of the first switching unit, the first electrode of the first transistor serves as the first terminal of the first switching unit, the second electrode of the first transistor serves as the second terminal of the first switching unit, and the gate of the second transistor serves as the control terminal of the second switching unit. The first electrode of the second transistor serves as the first terminal of the second switching unit, and the second electrode of the second transistor serves as the second terminal of the second switching unit. The first transistor and the second transistor have different channel types.

2. The pseudo-resistance control circuit according to claim 1, characterized in that, The first transistor is a PMOS transistor, and the second transistor is an NMOS transistor.

3. 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, and the second end of the current adjustment unit serves as the output end of the adjustment module. The current adjustment unit is used to adjust the control current according to the first input voltage. The first terminal of the current-to-voltage unit is connected to the second terminal of the current adjustment unit, the control terminal of the current-to-voltage unit is connected to the first terminal of the current-to-voltage unit, and the second terminal of the current-to-voltage unit is grounded. The current-to-voltage unit is used to convert the adjusted control current into the voltage of the pseudo-resistor control terminal.

4. The pseudo-resistance control circuit according to claim 3, characterized in that, The current adjustment unit includes a third transistor; The first terminal of the third transistor serves as the first terminal of the current adjustment unit, the second terminal of the third transistor serves as the second terminal of the current adjustment unit, and the gate of the third transistor serves as the control terminal of the current adjustment unit.

5. The pseudo-resistance control circuit according to claim 3, characterized in that, The current-to-voltage conversion unit includes a fourth transistor, the first terminal of the fourth transistor serves as the first terminal of the current-to-voltage conversion unit, the second terminal of the fourth transistor serves as the second terminal of the current-to-voltage conversion unit, and the gate of the fourth transistor serves as the control terminal of the current-to-voltage conversion unit.

6. A pseudo-resistance providing device, characterized in that, Includes a pseudo resistor and the pseudo resistor control circuit as described in any one of claims 1-5; The control terminal of the pseudo resistor is connected to the output terminal of the pseudo resistor control circuit, which is used to control the resistance value of the pseudo resistor.

7. The pseudo-resistance providing device according to claim 6, characterized in that, The pseudo-resistor includes a fifth transistor; The gate of the fifth transistor serves as the control terminal of the pseudo resistor, the first terminal of the fifth transistor is connected to the first input voltage, and the second terminal of the fifth transistor is connected to the second input voltage.

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