Self-regulating switched resistor, filter including self-regulating switched resistor, and electronic system

Abstract

A self-regulating switched resistor, a filter including the self-regulating switched resistor, and an electronic system are provided. The self-regulating switched resistor includes: a first resistor having a first resistance; a switch connected in series with the first resistor; and a control signal generation circuit configured to generate a switch control signal for the switch to adjust an equivalent resistance of a combination of the first resistor and the switch, where a duty cycle of the switch control signal changes in response to a change in the first resistance such that the equivalent resistance of the combination of the first resistor and the switch remains unchanged. Therefore, the self-regulating switching resistor can generate a large equivalent resistance, has a reduced chip area, and has an equivalent resistance with a constant resistance value.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to resistors, and more particularly, to a self-adjusting switched resistor, a filter including the self-adjusting switched resistor, and an electronic system. BACKGROUND

[0002] As the demand for miniaturization and high performance of electronic devices is increasing, a filter including a resistor implemented on-chip is being researched. However, the chip area of the resistor implemented on-chip is large, and the resistance value of the resistor implemented on-chip is also easily affected by process, power supply, and temperature, thereby causing the cutoff frequency of the filter to deviate from a set value. Accordingly, there is a need for a resistor implemented on-chip that has a reduced size and a resistance value that is not affected by process, power supply, and temperature. SUMMARY

[0003] An object of the present disclosure is to provide a self-adjusting switched resistor capable of generating a large equivalent resistance, having a reduced chip area, and having a constant equivalent resistance, a filter including the self-adjusting switched resistor, and an electronic system.

[0004] According to one embodiment of the present inventive concept, there is provided a self-adjusting switched resistor, the self-adjusting switched resistor including: a first resistor having a first resistance; a switch connected in series with the first resistor; and a control signal generation circuit configured to generate a switching control signal for the switch to adjust an equivalent resistance of a combination of the first resistor and the switch, wherein a duty cycle of the switching control signal changes in response to a change in the first resistance such that the equivalent resistance of the combination of the first resistor and the switch remains constant.

[0005] Optionally, the duty cycle of the switching control signal decreases in response to a decrease in the first resistance, and the duty cycle of the switching control signal increases in response to an increase in the first resistance.

[0006] Optionally, the control signal generation circuit includes: a comparator including a first input terminal and a second input terminal, and configured to output the switching control signal; a resistance detection circuit connected to the first input terminal of the comparator, and configured to output a voltage signal indicating a voltage of a second resistor of the resistance detection circuit; and a sawtooth wave generation circuit connected to the second input terminal of the comparator, and configured to output a sawtooth wave signal.

[0007] Optionally, the comparator is configured to output the switching control signal based on a comparison result of the voltage signal and the sawtooth wave signal.

[0008] Optionally, the comparator is configured to output the switch control signal having a first level based on the value of the voltage signal of the second resistor being greater than the value of the sawtooth signal, and output the switch control signal having a second level different from the first level based on the value of the voltage signal of the second resistor being less than the value of the sawtooth signal.

[0009] Optionally, the resistance detection circuit includes a current source, and a second resistor connected in series between the current source and the ground.

[0010] Optionally, the first resistor and the second resistor are the same resistor.

[0011] According to an embodiment of the inventive concept, there is provided a filter comprising a self-adjusting switched resistor, the filter comprising: an input terminal; an output terminal; a self-adjusting switched resistor as described above connected between the input terminal and the output terminal; and a capacitor connected between the self-adjusting switched resistor and the output terminal.

[0012] According to an embodiment of the inventive concept, there is provided an electronic system comprising a filter as described above.

[0013] Optionally, the electronic system further comprises: an anti-aliasing filter connected to the output terminal of the filter.

[0014] The self-adjusting switched resistor of the present disclosure has a structure in which a switch and a first resistor are connected in series, and a switch control signal is controlled to generate a very large equivalent resistance with a small duty cycle, reducing the area of a chip. In addition, the switch control signal of the present disclosure is generated based on a second resistor identical to the first resistor, so that the equivalent resistance of the self-adjusting switched resistor can be adjusted to remain constant based on the resistance value change of the second resistor. BRIEF DESCRIPTION OF DRAWINGS

[0015] The above and / or other aspects of the present disclosure will become apparent and more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings, in which:

[0016] Figure 1 is a block diagram of a self-adjusting switched resistor according to an example embodiment of the present disclosure.

[0017] Figure 2 is a circuit diagram of a control signal generation circuit according to an example embodiment of the present disclosure.

[0018] Figure 3 is a graph of a switch control signal according to an example embodiment of the present disclosure.

[0019] Figure 4 is a block diagram of a filter according to an example embodiment of the present disclosure.

[0020] Figure 5 is a block diagram of an electronic system according to example embodiments of the present disclosure.

[0021] Throughout the drawings and detailed description, unless otherwise described or provided, like reference numerals will be understood to refer to like elements, features and structures. The drawings can not be to scale and the dimensions, proportions and other numerical descriptions are intended to aid in understanding the examples described herein and are not intended to be limiting. Similarly, like reference numerals in the drawings will be understood to refer to like elements, features and structures. DETAILED DESCRIPTION

[0022] The following detailed description is provided to aid in understanding the methods, devices and / or systems described herein. No single feature, design, or implementation described herein is a sole cause of an effect described herein. Various changes, modifications and equivalents can be used and additional features beyond those described herein can be implemented to aid in achieving an effect described herein. For example, order of operations can be changed between those described herein, unless an operation is specifically dependent on another operation being performed first. Moreover, although features can be described as being a certain size, shape, or position, features can be scaled as appropriate and / or can be different than as described, unless described as "essential" or "critical". In addition, descriptions of a feature known to one of ordinary skill in the art can be omitted so as to not obscure the description of other features. Further, to the extent that any reference is made to a patent or non-patent publication, that reference is made solely for the purpose of describing the disclosure and does not constitute an admission that the patent or non-patent publication is prior art.

[0023] The features described herein can be implemented in different ways depending upon the particular application or applications. Rather than be limited to the examples described herein, it is contemplated that the examples described herein will cover variations, equivalents, and alternatives falling within the scope of the methods, devices and / or systems described herein.

[0024] Throughout this specification, where a component is described as being "connected to" or "coupled to" another component, it will be understood that the component can be directly connected or coupled to the other component, or one or more intervening components can be present. Conversely, where a component is described as being "directly connected to" or "directly coupled to" another component, it will be understood that no intervening components are present. Similarly, expressions such as "between" and "amongst", and "adjacent" and "immediately adjacent", should also be interpreted in the same way. As used herein, the term "and / or" includes any one of the listed items or any combination of two or more of the listed items.

[0025] Although terms such as "first", "second", and "third" can be used herein to describe various components, assemblies, regions, layers or sections, these components, assemblies, regions, layers or sections should not be limited by these terms. Instead, these terms are only used to distinguish one component, assembly, region, layer or section from another component, assembly, region, layer or section. Thus, a component, assembly, region, layer or section referred to as the first component, the first assembly, the first region, the first layer or the first section in the examples described herein can also be referred to as the second component, the second assembly, the second region, the second layer or the second section without departing from the teachings of the examples.

[0026] The terms used herein are only used to describe various examples and will not be used to limit the disclosure. The singular form also intends to include the plural form unless the context clearly indicates otherwise. The terms "comprise", "include" and "have" indicate the presence of stated features, numbers, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, operations, components, elements and / or combinations thereof.

[0027] Unless otherwise defined, all terms used herein (including technical terms and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art based on the understanding of the disclosure and the context of the disclosure. Unless explicitly defined herein, the terms (such as terms defined in a general dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the disclosure of the present application, and should not be interpreted ideally or overly formally. The use of the term "may" herein with respect to examples or embodiments (e.g., with respect to what examples or embodiments can include or implement) means that there is at least one example or embodiment that includes or implements such a feature, and all examples are not limited thereto.

[0028] Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0029] Figure 1 is a block diagram of a self-adjusting switching resistor 100 according to an example embodiment of the present disclosure.

[0030] Referring to Figure 1 , the self-adjusting switching resistor 100 according to an example embodiment of the present disclosure can include a first resistor R1, a switch 110, and a control signal generation circuit 120.

[0031] The first resistor R1 can have a first resistance (or a first resistance value) r1. The switch 110 can be connected in series with the first resistor R1. The control signal generation circuit 120 can be configured to generate a switch control signal Sc for the switch 110 to adjust an equivalent resistance r E .

[0032] According to an example embodiment of this disclosure, the switching 110 can be turned off based on the control of the switch control signal Sc. Therefore, the self-adjusting switching resistor 100 can achieve a large equivalent resistance.

[0033] In one example, the first resistor R1 can be a polysilicon resistor, and the self-adjusting switching resistor 100 is an on-chip switching resistor. In this case, the structure of the switch 110 controlled by the switching control signal Sc and the polysilicon resistor connected in series can generate a very large equivalent resistance with only a small duty cycle of the switching control signal Sc, thus reducing the chip area.

[0034] According to an exemplary embodiment of this disclosure, the duty cycle of the switch control signal Sc changes in response to a change in the first resistor r1, such that the equivalent resistance r of the combination of the first resistor R1 and the switch 110 is... E (or the equivalent resistance r of the self-adjusting switching resistor 100) E The duty cycle of the switch control signal Sc remains unchanged. In one example, the duty cycle of the switch control signal Sc may decrease in response to a decrease in the first resistor r1, and the duty cycle of the switch control signal Sc may increase in response to an increase in the first resistor r1. This is because the equivalent resistance r of the self-adjusting switch resistor 100 remains constant. E It is not affected by the change in the resistance value of the first resistor R1.

[0035] In the following text, reference will be made to Figure 2 Describe in detail the control signal generation circuit 120.

[0036] Figure 2 This is a circuit diagram of a control signal generation circuit 120 according to an exemplary embodiment of the present disclosure.

[0037] Reference Figure 2 The control signal generation circuit 120 may include a comparator 121, a resistance detection circuit 122, and a sawtooth wave generation circuit 123.

[0038] Comparator 121 may include a first input terminal and a second input terminal, and may be configured to output a switch control signal Sc. In one example, the first input terminal may be a positive input terminal or a negative input terminal (…). Figure 2 In the comparator, the "+" sign indicates a positive input terminal, and the second input terminal can be either a negative input terminal or a negative input terminal (the "-" sign indicates a negative input terminal). This will be discussed further below. Figure 3 The details of the comparator 121 output switch control signal Sc are described in detail. The sawtooth wave generation circuit 123 can be connected to the second input terminal of the comparator 121 and can be configured to output a sawtooth wave signal V. PWL .

[0039] The resistance detection circuit 122 can be connected to the first input terminal of the comparator 121 and can be configured to output a voltage signal V indicating the voltage of the second resistor R2 of the resistance detection circuit 122. T The resistance detection circuit 122 may include a current source I. REF And the second resistor R2. Current source I REF It can be a constant current source. The second resistor R2 can be connected in series with the current source I. REF Between and GND.

[0040] According to embodiments of this disclosure, the first resistor R1 and the second resistor R2 can be the same resistor. For example, the first resistor R1 and the second resistor R2 can have the same specifications and / or be manufactured by the same process, such that the first resistor R1 and the second resistor R2 can exhibit the same resistance change in response to the effects of manufacturing process, power supply voltage, and temperature.

[0041] Since the first resistor R1 and the second resistor R2 are the same resistors, and the switch control signal Sc is generated based on the second resistor, which is the same as the first resistor, the resistance change of the first resistor R1 in response to the effects of manufacturing process, power supply voltage, and temperature is the same as the resistance change of the second resistor R2 in response to the effects of manufacturing process, power supply voltage, and temperature. This makes the equivalent resistance r of the self-adjusting switch resistor 100... E It can be adjusted to remain constant based on the change in the resistance value of the second resistor R2.

[0042] Figure 3 This is a graph of the switch control signal Sc according to an example embodiment of the present disclosure.

[0043] According to an example embodiment of this disclosure, comparator 121 may be configured to: based on voltage signal V T With sawtooth wave signal V PWL The comparison result outputs a switch control signal Sc. In one example, refer to... Figure 3 Comparator 121 can be configured to: based on the voltage signal V of the second resistor R2 T The value is greater than the sawtooth wave signal V. PWL The value of the output switch control signal Sc with a first level is determined, and the voltage signal V is based on the second resistor R2. T The value is less than the sawtooth wave signal V PWL The value of is used to output a switch control signal Sc with a second level that is different from the first level. For example...Figure 3 As shown, the first level can be a logic high level, and the second level can be a logic low level.

[0044] According to one embodiment, in Figure 1 Switch 110 is turned on only when the control signal Sc is high. Figure 2 The input signals of the comparator can be: a voltage signal VT connected to the positive input terminal, and a sawtooth wave signal VPWL connected to the negative input terminal. However, it should be understood that this disclosure is not limited thereto. For example, according to another embodiment, in Figure 1 Switch 110 is turned on only when the control signal Sc is low. Figure 2 The input signal of the comparator in the circuit can be: voltage signal V T Connect to the negative input terminal, sawtooth wave signal V PWL Connect to the positive input terminal.

[0045] The process of how the change in the second resistor R2 causes the change in the switch control signal SC is as follows: Figure 3 As shown. When changes in process, power supply, or temperature cause the resistance of the second resistor R2 to increase, the voltage signal VT increases accordingly. The high-level duration of the switch control signal SC obtained after voltage comparison also increases, and the duty cycle D increases (the duty cycle D is defined as the ratio of the high-level duration to the period). Therefore, the equivalent resistance r of the self-adjusting switch resistor 100... E The duty cycle D will decrease; conversely, when changes in process, power supply, or temperature cause the resistance of the second resistor R2 to decrease, the duty cycle D will also decrease, while the equivalent resistance r of the self-adjusting switching resistor 100 will decrease. E It will get bigger.

[0046] Figure 4 This is a block diagram of a filter 200 according to an exemplary embodiment of the present disclosure.

[0047] Reference Figure 4 The filter 200 may include an input terminal 210, an output terminal 220, a self-adjusting switching resistor 100, and a capacitor 230.

[0048] In one example, filter 200 may be a low-pass filter, but is not limited to this. In one example, filter 200 may be a first-order filter, but is not limited to this. For example, filter 200 may be a higher-order filter.

[0049] The self-adjusting switching resistor 100 can be used as a reference. Figures 1 to 2The self-adjusting switching resistor 100 is described and can be connected between input terminal 210 and output terminal 220. A capacitor 230 can be connected between the self-adjusting switching resistor 100 and output terminal 220. That is, the capacitor 230 can be disposed between the output terminal of the self-adjusting switching resistor 100 and output terminal 220.

[0050] Because the self-adjusting switching resistor 100 can achieve a large equivalent resistance, the chip area can be reduced, and the equivalent resistance r of the self-adjusting switching resistor 100... E Unaffected by manufacturing process, power supply voltage, and temperature, the performance of filter 200 can be improved, and its size can be miniaturized.

[0051] Figure 5 This is a block diagram of an electronic system 1000 according to an exemplary embodiment of the present disclosure.

[0052] Reference Figure 5 The electronic system 1000 may include a filter 200. The filter 200 may be a reference... Figure 4 The filter described. In an optional example, the electronic system 1000 may also include an anti-aliasing filter 300. The anti-aliasing filter 300 may be connected to the output terminal of the filter 200. The anti-aliasing filter 300 can eliminate fluctuations caused by the switching control signal Sc, thereby improving the quality of the output signal of the filter 200.

[0053] The self-adjusting switching resistor 100 disclosed herein has a structure in which a switch 110 controlled by a switching control signal Sc is connected in series with a first resistor. Only a switching control signal Sc with a small duty cycle is needed to generate a very large equivalent resistance, reducing the chip area. Furthermore, the switching control signal Sc of this disclosure is generated based on a second resistor identical to the first resistor; therefore, the equivalent resistance r of the self-adjusting switching resistor 100 is... E It can be adjusted to remain constant based on the change in the resistance value of the second resistor R2.

[0054] Although the invention has been specifically shown and described with reference to exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the claims.

Claims

1. A self-adjusting switching resistor, characterized in that, The self-adjusting switching resistor includes: The first resistor has a first resistance; The switch is connected in series with the first resistor; and A control signal generation circuit is configured to generate a switch control signal for the switch to adjust the equivalent resistance of the combination of the first resistor and the switch. The duty cycle of the switch control signal changes in response to the change of the first resistor, so that the equivalent resistance of the combination of the first resistor and the switch remains unchanged.

2. The self-adjusting switching resistor according to claim 1, characterized in that, The duty cycle of the switch control signal decreases in response to a decrease in the first resistor, and increases in response to an increase in the first resistor.

3. The self-adjusting switching resistor according to claim 1, characterized in that, The control signal generation circuit includes: The comparator includes a first input terminal and a second input terminal, and is configured to output a switch control signal; A resistance sensing circuit, connected to the first input terminal of a comparator, is configured to output a voltage signal indicating the voltage of a second resistor in the resistance sensing circuit; and The sawtooth wave generation circuit is connected to the second input terminal of the comparator and is configured to output a sawtooth wave signal.

4. The self-adjusting switching resistor according to claim 3, characterized in that, The comparator is configured to output a switching control signal based on the comparison result between the voltage signal and the sawtooth wave signal.

5. The self-adjusting switching resistor according to claim 4, characterized in that, The comparator is configured as follows: Based on the fact that the voltage signal from the second resistor is greater than the value of the sawtooth wave signal, a switch control signal with a first level is output, and Based on the fact that the voltage signal of the second resistor is less than the value of the sawtooth wave signal, a switch control signal with a second level different from the first level is output.

6. The self-adjusting switching resistor according to claim 3, characterized in that, The resistance detection circuit includes: Current source; and The second resistor is connected in series between the current source and ground.

7. The self-adjusting switching resistor according to claim 3 or 6, characterized in that, The first resistor and the second resistor are the same resistor.

8. A filter comprising a self-adjusting switching resistor, characterized in that, The filter includes: Input terminals; Output terminals; The self-adjusting switching resistor according to any one of claims 1 to 7 is connected between the input terminal and the output terminal; and A capacitor is connected between the self-adjusting switching resistor and the output terminal.

9. An electronic system, characterized in that, The electronic system includes the filter according to claim 8.

10. The electronic system according to claim 9, characterized in that, The electronic system further includes an anti-aliasing filter connected to the output terminal of the filter.

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