Signal calibration module, analog-to-digital converter, chip and signal calibration method

Abstract

The invention provides a signal calibration module, an analog-to-digital converter, a chip and a signal calibration method. The analog-to-digital converter comprises a reference voltage unit, a voltage calibration unit and a control unit. Wherein the control unit is used for outputting a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter; the reference voltage unit is used for outputting a reference voltage to the input end of the analog-to-digital converter according to the first control instruction; the control unit is also used for outputting a second control instruction to the voltage calibration unit according to the output voltage of the comparison module; the voltage calibration unit is used for outputting reference voltage to the first input end of the comparison module according to the second control instruction. The signal calibration module is simple in structure, easy to integrate, low in cost and high in calibration efficiency.

Description

Technical Field

[0001] The present application relates to the field of electronic circuit technology, and in particular to a signal calibration module, an analog-to-digital converter, a chip, and a signal calibration method. Background Art

[0002] Analog-to-digital converters (ADCs) convert analog signals into digital signals and are widely used in industrial measurement, wireless communications, image recognition, and other fields. While there are many different types of ADCs, high-precision successive approximation analog-to-digital converters (SAR ADCs) are highly favored in low-speed, low-power applications due to their simple structure and high process compatibility.

[0003] Due to manufacturing process variations, ADC accuracy can be affected, necessitating calibration. Current ADC calibration solutions are complex to implement, requiring increased circuit area and control modules, resulting in high costs and low calibration efficiency. Summary of the Invention

[0004] The main purpose of this application is to provide a signal calibration module, an analog-to-digital converter, a chip and a signal calibration method, aiming to solve the problems of high cost and low calibration efficiency of current ADC calibration solutions.

[0005] In a first aspect, the present application provides a signal calibration module, the signal calibration module comprising a reference voltage unit, a voltage calibration unit, and a control unit;

[0006] The input end of the reference voltage unit is used to connect to a first voltage source, the output end of the reference voltage unit is used to connect to the input end of the analog-to-digital converter, and the controlled end of the reference voltage unit is connected to the first control end of the control unit;

[0007] The input end of the voltage calibration unit is used to connect to a second voltage source, the output end of the voltage calibration unit is used to connect to the first input end of the comparison module of the analog-to-digital converter, the controlled end of the voltage calibration unit is connected to the second control end of the control unit; the second input end of the comparison module is connected to the input end of the analog-to-digital converter;

[0008] The input end of the control unit is used to connect to the output end of the comparison module, and the output end of the control unit is used to connect to the output end of the analog-to-digital converter;

[0009] The control unit is used to output a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter; the reference voltage unit is used to output a reference voltage to the input end of the analog-to-digital converter according to the first control instruction;

[0010] The control unit is further configured to output a second control instruction to the voltage calibration unit according to the output voltage of the comparison module; and the voltage calibration unit is configured to output a reference voltage to the first input terminal of the comparison module according to the second control instruction.

[0011] In a second aspect, an embodiment of the present application further provides an analog-to-digital converter, comprising:

[0012] Input and output terminals;

[0013] a comparison module, wherein a second input terminal of the comparison module is connected to an input terminal of the analog-to-digital converter;

[0014] The signal calibration module as described in any one of the embodiments of the present application is connected to the input and output ends of the analog-to-digital converter, and is also connected to the first input and output ends of the comparison module; the signal calibration module is used to perform signal calibration on the input voltage of the analog-to-digital converter.

[0015] In a third aspect, an embodiment of the present application further provides an integrated circuit chip, characterized in that it includes a substrate and an analog-to-digital converter as described in any one of the embodiments of the present application, wherein the analog-to-digital converter is arranged on the substrate.

[0016] In a fourth aspect, embodiments of the present application further provide a signal calibration method, which is applied to the signal calibration module as described in any one of the embodiments of the present application, and the method includes:

[0017] outputting a first control instruction to a reference voltage unit according to an input voltage of the analog-to-digital converter, wherein the first control instruction is used to control the reference voltage unit to output a reference voltage to an input terminal of the analog-to-digital converter;

[0018] An output voltage of the comparison module is received, and a second control instruction is output to the voltage calibration unit according to the output voltage, wherein the second control instruction is used to control the voltage calibration unit to output a reference voltage to the first input terminal of the comparison module.

[0019] An embodiment of the present application provides a signal calibration module for an analog-to-digital converter, comprising a reference voltage unit, a voltage calibration unit, and a control unit. The control unit is configured to output a first control instruction to the reference voltage unit based on the input voltage of the analog-to-digital converter; the reference voltage unit is configured to output a reference voltage to the input terminal of the analog-to-digital converter based on the first control instruction. The control unit is further configured to output a second control instruction to the voltage calibration unit based on the output voltage of the comparison module; the voltage calibration unit is configured to output a reference voltage to the first input terminal of the comparison module based on the second control instruction. The signal calibration module can evaluate the signal deviation of the analog-to-digital converter by outputting a reference voltage, and can output a reference voltage to calibrate the signal deviation, thereby eliminating the effects caused by the signal deviation. The signal calibration module has a relatively simple structure and is easy to integrate, with a small circuit area, which can save signal calibration costs. The signal calibration module utilizes a self-calibration mechanism, does not require software resources, and does not rely on external test signals, thereby greatly improving signal calibration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 A circuit diagram of an implementation of a signal calibration module provided in an embodiment of the present application;

[0022] Figure 2 A circuit diagram of an implementation of a reference voltage unit provided in an embodiment of the present application;

[0023] Figure 3 A circuit diagram of another embodiment of the reference voltage unit provided in the embodiment of the present application;

[0024] Figure 4 A circuit diagram of an embodiment of a control unit provided in an embodiment of the present application;

[0025] Figure 5 A circuit diagram of an embodiment of an analog-to-digital converter provided in an embodiment of the present application;

[0026] Figure 6 A circuit diagram of another embodiment of the analog-to-digital converter provided in an embodiment of the present application;

[0027] Figure 7 A circuit diagram of another embodiment of the analog-to-digital converter provided in an embodiment of the present application;

[0028] Figure 8 A circuit diagram of another embodiment of the analog-to-digital converter provided in an embodiment of the present application;

[0029] Figure 9 A schematic block diagram of an integrated circuit chip provided in an embodiment of the present application;

[0030] Figure 10 A schematic flow chart of one step of the signal calibration method provided in an embodiment of the present application.

[0031] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0032] It should be noted that the terms "first" and "second" in the description, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence.

[0033] It should also be noted that the method disclosed in the embodiments of the present application or the method shown in the flowchart includes one or more steps for implementing the method. Without departing from the scope of the claims, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0034] The main factors that limit the performance of analog-to-digital converters (ADCs) include comparator offset, noise, capacitor parasitics, and capacitor mismatch. Manufacturing process variations can cause comparator offset, which can affect ADC accuracy.

[0035] Calibration can be categorized as software calibration and analog calibration. Analog calibration involves using designed analog modules to detect and compensate for ADC mismatch. Compensation capacitors are typically used to calibrate the capacitor array of the analog-to-digital converter. However, this calibration solution is complex and consumes a lot of area. Software calibration involves testing the ADC offset at the factory, recording it in a software chip, and then using software to calibrate the ADC output. However, this method is inconvenient for real-time calibration and has relatively low calibration efficiency.

[0036] Based on this, the embodiments of the present application provide a signal calibration module, an analog-to-digital converter, a chip, and a signal calibration method, which can solve the problems of high cost and low calibration efficiency of current ADC calibration solutions.

[0037] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0038] Please refer to Figure 1 , Figure 1 This is a circuit diagram of an implementation of the signal calibration module provided in an embodiment of the present application.

[0039] like Figure 1 As shown, the signal calibration module 100 is disposed in the analog-to-digital converter. The signal calibration module 100 includes a reference voltage unit 110 , a voltage calibration unit 120 and a control unit 130 .

[0040] Specifically, the analog-to-digital converter includes an input terminal ADC-in and an output terminal ADC-out. The input terminal ADC-in is used to receive an input voltage sent externally, and the output terminal ADC-out is used to send an output voltage externally. The analog-to-digital converter also includes a comparison module 210 connected to the signal calibration module 100. The comparison module 210 is used to compare the voltages received at the two input terminals and output a corresponding voltage signal. The voltage signal can be a binary signal such as 0 or 1.

[0041] The input terminal of the reference voltage unit 110 is connected to the first voltage source VCC1, the output terminal of the reference voltage unit 110 is connected to the input terminal ADC-in of the analog-to-digital converter, and the controlled terminal of the reference voltage unit 110 is connected to the first control terminal of the control unit 130. The input terminal of the voltage calibration unit 120 is connected to the second voltage source VCC2, the output terminal of the voltage calibration unit 120 is connected to the first input terminal of the comparison module 210 of the analog-to-digital converter, and the controlled terminal of the voltage calibration unit 120 is connected to the second control terminal of the control unit 130. The second input terminal of the comparison module 210 is connected to the input terminal ADC-in of the analog-to-digital converter. The input terminal of the control unit 130 is connected to the output terminal of the comparison module 210, and the output terminal of the control unit 130 is connected to the output terminal ADC-out of the analog-to-digital converter.

[0042] It should be noted that the control unit 130 is configured to output a first control instruction to the reference voltage unit 110 based on the input voltage of the analog-to-digital converter; the reference voltage unit 110 is configured to output the reference voltage to the input terminal of the analog-to-digital converter based on the first control instruction. The control unit 130 is also configured to output a second control instruction to the voltage calibration unit 120 based on the output voltage of the comparison module 210; the voltage calibration unit 120 is configured to output the reference voltage to the first input terminal of the comparison module 210 based on the second control instruction.

[0043] It should be noted that the input voltage of the analog-to-digital converter may be an external voltage signal input to the input terminal ADC-in, and the output voltage of the comparison module 210 may be a voltage signal sent from the output terminal of the comparison module 210 to the input terminal of the control unit 130. The reference voltage output by the reference voltage unit 110 and the reference voltage output by the voltage calibration unit 120 are both adjustable. For example, the reference voltage may be determined based on the input voltage of the analog-to-digital converter, and the reference voltage may be determined based on the output voltage of the comparison module 210.

[0044] For example, the control unit 130 can determine the reference voltage to be output by the reference voltage unit 110 based on the input voltage of the analog-to-digital converter, thereby generating a first control instruction. By outputting the first control instruction to the reference voltage unit 110, the reference voltage unit 110 can be accurately controlled to output the reference voltage to the input terminal of the analog-to-digital converter. This reference voltage can compensate for the input voltage of the analog-to-digital converter. The compensated input voltage can be input to the second input terminal of the comparison module 210. At this time, the voltage calibration unit 120 outputs the reference voltage to the first input terminal of the comparison module 210. Furthermore, the output terminal of the comparison module 210 can transmit the output voltage to the control unit 130. The control unit 130 can determine the reference voltage to be output by the voltage calibration unit 120 based on the output voltage of the comparison module 210, thereby generating a second control instruction. By outputting the second control instruction to the voltage calibration unit 120, the voltage calibration unit 120 can be accurately controlled to output the reference voltage to the first input terminal of the comparison module 210. This reference voltage can serve as a reference voltage for the comparison module 210 to calibrate the signal deviation of the analog-to-digital converter, thereby eliminating the effects caused by signal deviation.

[0045] In the embodiment of the present application, the reference voltage unit 110 outputs a reference voltage to evaluate the signal deviation of the analog-to-digital converter, and the voltage calibration unit 120 outputs a reference voltage to calibrate the signal deviation, thereby eliminating the influence caused by the signal deviation. The structure of the signal calibration module 100 is relatively simple and easy to integrate, and the circuit area is small, which can save signal calibration costs. The signal calibration module 100 uses a self-calibration mechanism, does not need to consume software resources, and does not rely on external test signals, thereby greatly improving the signal calibration efficiency. Therefore, the problem of high cost and low calibration efficiency of the current ADC calibration solution can be solved.

[0046] In one embodiment, please refer to Figure 2 , Figure 2 This is a circuit diagram of an embodiment of the reference voltage unit provided in the present application. Figure 2 As shown, the reference voltage unit 110 includes a grounding resistor R1 and a voltage dividing unit 111 .

[0047] The input end of voltage divider unit 111 is connected to a first voltage source VCC1. The voltage divider end of voltage divider unit 111 serves as the output end of voltage calibration unit 120 and is connected to the input end ADC-in of the analog-to-digital converter. The controlled end of voltage divider unit 111 serves as the controlled end of reference voltage unit 110 and is connected to a first control end of control unit 130. The output end of voltage divider unit 111 is connected to a first end of ground resistor R1, and a second end of ground resistor R1 is connected to ground GND.

[0048] It should be noted that control unit 130 is configured to output a first control instruction to voltage divider unit 111 based on the input voltage of the analog-to-digital converter. Voltage divider unit 111 is configured to control the conduction path between first voltage source VCC1 and the input terminal ADC-in of the analog-to-digital converter based on the first control instruction, thereby outputting a reference voltage to the input terminal ADC-in of the analog-to-digital converter. The voltage compensation function of reference voltage unit 110 can be easily implemented using grounding resistor R1 and voltage divider unit 111, with minimal implementation effort and low cost.

[0049] Exemplarily, the voltage divider unit 111 includes a resistor R2 and a switch S0. The first end of the resistor R2 serves as the input end of the voltage divider unit and is connected to the first voltage source VCC1. The second end of the resistor R2 serves as the output end of the voltage divider unit and is connected to the ground resistor R1. The first end of the switch S0 is connected to the second end of the resistor R2. The second end of the switch S0 serves as the voltage divider end of the voltage divider unit 111 and is connected to the input end ADC-in of the analog-to-digital converter.

[0050] In one embodiment, the reference voltage unit 110 includes a grounding resistor and multiple voltage divider units. A first-stage voltage divider unit among the multiple voltage divider units is connected to a first voltage source VCC1. An intermediate-stage voltage divider unit among the multiple voltage divider units is connected to the first-stage voltage divider unit or the intermediate-stage voltage divider unit of the previous stage. A final-stage voltage divider unit among the multiple voltage divider units is connected to the final intermediate-stage voltage divider unit. The final-stage voltage divider unit is also connected to a grounding resistor, which is also grounded. The controlled terminals of the multiple voltage divider units are respectively connected to a first control terminal of a control unit 130. The multiple voltage divider units are also connected to an input terminal ADC-in of an analog-to-digital converter. The control unit 130 is further configured to output a first control instruction to at least one voltage divider unit based on the input voltage of the analog-to-digital converter, so that the reference voltage unit 110 outputs a reference voltage that matches the input voltage to the input terminal ADC-in of the analog-to-digital converter.

[0051] It should be noted that there may be multiple voltage divider units, which may be connected in cascade. The control unit 130 may output a first control instruction to each of the multiple voltage divider units, thereby controlling the magnitude of the reference voltage output by the first voltage source VCC1 to the input terminal ADC-in of the analog-to-digital converter. This reference voltage may be matched to the input voltage, for example, according to a preset comparison table. The grounding resistor and multiple voltage divider units allow for accurate adjustment of the reference voltage, thereby improving signal calibration accuracy and reducing the number of signal calibrations for the same voltage signal, thereby improving signal calibration efficiency.

[0052] For example, please refer to Figure 3 , Figure 3 This is a circuit diagram of another embodiment of the reference voltage unit provided in the present application. Figure 3 As shown, the reference voltage unit 110 includes a grounding resistor R1 and multiple voltage divider units. Among the multiple voltage divider units, a first-stage voltage divider unit 112 is connected to a first voltage source VCC1. The intermediate-stage voltage divider units (including 114) are connected to the first-stage voltage divider unit or the intermediate-stage voltage divider unit of the previous stage. A final-stage voltage divider unit 116 is connected to the final intermediate-stage voltage divider unit. The final-stage voltage divider unit 116 is also connected to the grounding resistor R1, which is also grounded.

[0053] It should be noted that the controlled terminals of the multiple voltage divider units are respectively connected to the first control terminal of the control unit 130. The multiple voltage divider units are also connected to the input terminal ADC-in of the analog-to-digital converter. The control unit 130 is further configured to output a first control instruction to at least one voltage divider unit based on the input voltage of the analog-to-digital converter, so that the reference voltage unit 110 outputs a reference voltage that matches the input voltage to the input terminal of the analog-to-digital converter.

[0054] In one embodiment, the voltage divider unit includes a first resistor and a first switch; the first end of the first resistor serves as an input end of the voltage divider unit and is connected to a first voltage source VCC1 or a voltage divider unit of a previous stage; the second end of the first resistor serves as an output end of the voltage divider unit and is connected to a ground resistor or a voltage divider unit of a next stage; the first end of the first switch is connected to the second end of the first resistor; and the second end of the first switch serves as a voltage divider end of the voltage divider unit and is used to be connected to an input end ADC-in of an analog-to-digital converter.

[0055] It should be noted that the specific configuration of the voltage divider unit can be determined based on actual circumstances, and may include, for example, multiple resistors, switches, or other devices connected in series or parallel, and this application does not impose specific limitations thereon. The first switch may be a transistor, a MOS transistor, or, of course, other types of switching devices. The circuit comprising the voltage divider unit using the first resistor and the first switch is inexpensive to implement and has low cost.

[0056] For example, Figure 3 As shown, the first-stage voltage dividing unit 112 includes a resistor Rf and a switch SP <n>The first end of the resistor Rf serves as the input end of the first voltage divider unit 112 and is connected to the first voltage source VCC1. The second end of the resistor Rf serves as the output end of the first voltage divider unit 112 and is connected to the next voltage divider unit. <n>The first end of the switch SP is connected to the second end of the resistor Rf; <n>The second end of the switch SP serves as the voltage dividing end of the first voltage dividing unit 112 and is used to connect to the input end ADC-in of the analog-to-digital converter. <n>The controlled end of the first-stage voltage dividing unit 112 is connected to the first control end of the control unit 130.

[0057] For example, Figure 3 As shown, the intermediate voltage dividing unit 114 includes a resistor Rc and a switch SP <2> The first end of the resistor Rc serves as the input end of the intermediate voltage divider unit 114 and is connected to the voltage divider unit of the previous stage; the second end of the resistor Rc serves as the output end of the intermediate voltage divider unit 114 and is connected to the voltage divider unit of the next stage; the switch SP <2> The first end of the switch SP is connected to the second end of the resistor Rc; <2> The second end of the switch SP is used as the voltage dividing end of the intermediate voltage dividing unit 114, and is used to connect to the input end ADC-in of the analog-to-digital converter. <2> The controlled end of the intermediate voltage divider unit 114 is connected to the first control end of the control unit 130 as the controlled end of the intermediate voltage divider unit 114.

[0058] For example, Figure 3 As shown, the final voltage dividing unit 116 includes a resistor Ra and a switch SP <0> The first end of the resistor Ra serves as the input end of the final voltage divider unit 116 and is connected to the voltage divider unit of the previous stage; the second end of the resistor Ra serves as the output end of the final voltage divider unit 116 and is connected to the ground resistor R1; the switch SP <0> The first end of the switch SP is connected to the second end of the resistor Ra; <0> The second end of the switch SP is used as the voltage dividing end of the final voltage dividing unit 116, and is used to connect to the input end ADC-in of the analog-to-digital converter. <0> The controlled end of the final voltage divider unit 116 is connected to the first control end of the control unit 130 .

[0059] In one embodiment, the voltage calibration unit 120 includes a common-mode voltage (VCM) calibration unit, which includes multiple electronic voltage dividers connected in series or in parallel. It should be noted that an electronic voltage divider is a device that provides the same DC input voltage on two pins of a differential input. The specific connection relationship of the multiple electronic voltage dividers can be configured based on actual needs.

[0060] In one embodiment, please refer to Figure 4 , Figure 4 This is a circuit diagram of an embodiment of the control unit provided in the present application. Figure 4 As shown, the control unit 130 includes a controller 131 and a second switch 132 .

[0061] The first control terminal of the controller 131 is connected to the controlled terminal Vc of the reference voltage unit 110, and the second control terminal of the controller 131 is connected to the controlled terminal Vr of the voltage calibration unit 120. The input terminal of the controller 131 is connected to the first terminal a of the second switch 132. The second terminal b of the second switch 132 serves as the input terminal of the control unit 130 and is connected to the output terminal Vg of the comparison module 210. The third terminal c of the second switch 132 serves as the output terminal of the control unit 130 and is connected to the output terminal ADC-out of the analog-to-digital converter. The controller 131 is configured to control the second switch 132 to be disconnected during signal calibration and receive the output voltage of the comparison module 210. After the signal calibration is completed, the controller 131 is configured to control the second switch 132 to be connected, so that the second switch 132 outputs the output voltage to the output terminal of the analog-to-digital converter.

[0062] It should be noted that the second switch 132 can be a transistor, a MOS transistor, or of course, other types of switching devices. During the signal calibration process of the analog-to-digital converter, if the signal calibration is not completed, that is, during the signal calibration, the output voltage does not need to be output through the output terminal of the analog-to-digital converter. Only after the signal calibration is completed, the output voltage needs to be output through the output terminal of the analog-to-digital converter. Therefore, the circuit implementation cost of the control unit 130 composed of the controller 131 and the second switch 132 is low.

[0063] In one embodiment, the input terminal ADC-in and the output terminal ADC-out can be implemented in the form of a circuit. For example, the analog-to-digital converter may include a signal input circuit, and the signal input circuit includes the input terminal ADC-in. The reference voltage unit 110 and the comparison module 210 that need to be connected to the input terminal ADC-in can be connected to the signal input circuit respectively. The specific structure of the signal input circuit can be set according to the implementation situation. For example, the signal input circuit can be a circuit that can receive multiple signal inputs. For another example, the analog-to-digital converter may include a signal output circuit, and the signal output circuit includes the output terminal ADC-out. The control unit 130 can be connected to the signal output circuit. The specific structure of the signal input circuit can be set according to the implementation situation. The output voltage can be output through the signal output circuit.

[0064] The signal calibration module 100 of the analog-to-digital converter of the above embodiment includes a reference voltage unit 110, a voltage calibration unit 120, and a control unit 130. The control unit 130 is configured to output a first control instruction to the reference voltage unit 110 based on the input voltage of the analog-to-digital converter; the reference voltage unit 110 is configured to output a reference voltage to the input terminal of the analog-to-digital converter based on the first control instruction. The control unit 130 is further configured to output a second control instruction to the voltage calibration unit 120 based on the output voltage of the comparison module 210; the voltage calibration unit 120 is configured to output a reference voltage to the first input terminal of the comparison module 210 based on the second control instruction. The signal calibration module 100 can evaluate the signal deviation of the analog-to-digital converter by outputting a reference voltage and can also output the reference voltage to calibrate the signal deviation, thereby eliminating the effects caused by the signal deviation. The signal calibration module 100 has a relatively simple structure and is easy to integrate, with a small circuit area, which can reduce signal calibration costs. The signal calibration module 100 utilizes a self-calibration mechanism, eliminating the need for software resources and relying on external test signals, thereby significantly improving signal calibration efficiency.

[0065] Please refer to Figure 5 , Figure 5 A schematic block diagram of an analog-to-digital converter provided in an embodiment of the present application.

[0066] like Figure 5 As shown, the analog-to-digital converter 200 includes:

[0067] Input terminal ADC-in and output terminal ADC-out;

[0068] A comparison module 210, wherein a second input terminal of the comparison module 210 is connected to an input terminal ADC-in of the analog-to-digital converter 200;

[0069] The signal calibration module 220 of the above embodiment is connected to the input terminal ADC-in and the output terminal ADC-out of the analog-to-digital converter 200, and is also connected to the first input terminal and the output terminal Vg of the comparison module 210; the signal calibration module 220 is used to perform signal calibration on the input voltage of the analog-to-digital converter 200.

[0070] The input voltage of the analog-to-digital converter 200 may be a voltage signal input by an external device to the input terminal ADC-in of the analog-to-digital converter 200. The output voltage of the comparison module 210 may be a voltage signal sent from the output terminal of the comparison module 210 to the input terminal of the control unit 130. The voltage signal may be a binary signal such as 0 or 1. The signal calibration module 220 may be the signal calibration module 100 of the above-described embodiment.

[0071] It should be noted that the signal calibration module 220 may include a reference voltage unit, a voltage calibration unit, and a control unit. The signal deviation of the analog-to-digital converter is evaluated by outputting a reference voltage, and the reference voltage can be output to calibrate the signal deviation, thereby eliminating the influence caused by the signal deviation. The structure of the analog-to-digital converter 200 is relatively simple and easy to integrate, and the circuit area is small, which can save signal calibration costs. The analog-to-digital converter 200 uses a self-calibration mechanism, does not need to consume software resources, does not rely on external test signals, and can greatly improve the efficiency of signal calibration.

[0072] In one embodiment, if Figure 6 As shown, the comparison module 210 includes a comparator unit; the positive input terminal of the comparator unit serves as the first input terminal of the comparison module 210, the negative input terminal of the comparator unit serves as the second input terminal of the comparison module 210, and the output terminal of the comparator unit serves as the output terminal of the comparison module 210. It should be noted that when the first input terminal of the comparison module 210 is positive and the second input terminal is negative, the reference voltage output by the voltage calibration unit is proportional to the output voltage of the comparator unit.

[0073] In one embodiment, if Figure 7 As shown, the comparison module 210 includes a comparator unit; the positive input terminal of the comparator unit serves as the first input terminal of the comparison module 210, the negative input terminal of the comparator unit serves as the second input terminal of the comparison module 210, and the output terminal of the comparator unit serves as the output terminal of the comparison module 210. It should be noted that when the first input terminal of the comparison module 210 is negative and the second input terminal is positive, the reference voltage output by the voltage calibration unit is inversely proportional to the output voltage of the comparator unit.

[0074] In one embodiment, the input terminal ADC-in and the output terminal ADC-out can be implemented in a circuit manner. Figure 6 and Figure 7 As shown, the analog-to-digital converter may further include a signal input circuit and a signal output circuit. The signal input circuit may be connected to the input terminal ADC-in, and the signal output circuit may be connected to the output terminal ADC-out. In some examples, the control unit in the signal calibration module 220 may be connected to the controlled terminals of the signal input circuit and the signal output circuit, respectively, to control the signal input circuit and the signal output circuit.

[0075] In one embodiment, if Figure 8 As shown, the analog-to-digital converter may further include a sampling unit 230, one end of which is connected to the input terminal ADC-in, and the other end of which is connected to the comparison module 210. The sampling unit 230 may, for example, include a sampling switch and a sampling capacitor connected in series, or may be other forms of sampling circuits.

[0076] It can be understood that the beneficial effects that can be achieved by the analog-to-digital converter provided in the embodiment of the present application can refer to the beneficial effects of the signal calibration module in the corresponding embodiment provided above, and will not be repeated here.

[0077] Please refer to Figure 9 , Figure 9 A schematic block diagram of an integrated circuit chip provided in an embodiment of the present application.

[0078] like Figure 9 As shown, the integrated circuit chip 300 includes a substrate and the analog-to-digital converter 320 of the above embodiment, and the analog-to-digital converter 320 is arranged on the substrate 310. The integrated circuit chip 300 may of course include other circuits, which are not specifically limited in this application.

[0079] It can be understood that the beneficial effects that can be achieved by the integrated circuit chip provided in the embodiment of the present application can refer to the beneficial effects of the analog-to-digital converter or signal calibration module in the corresponding embodiment provided above, and will not be repeated here.

[0080] Please refer to Figure 10 , Figure 10 This is a flow chart of one step of the signal calibration method provided in an embodiment of the present application. The signal calibration method can be applied to the signal calibration module of the above embodiment, including a reference voltage unit, a voltage calibration unit and a control unit, as shown in the above figure.

[0081] The reference voltage unit has an input connected to a first voltage source, an output connected to an input of an analog-to-digital converter, and a controlled terminal connected to a first control terminal of a control unit. The voltage calibration unit has an input connected to a second voltage source, an output connected to a first input of a comparison module of the analog-to-digital converter, and a controlled terminal connected to a second control terminal of the control unit. The comparison module has a second input connected to an input of the analog-to-digital converter. The control unit has an input connected to an output of the comparison module, and an output connected to an output of the analog-to-digital converter.

[0082] like Figure 10 As shown, the signal calibration method includes steps S410 to S420.

[0083] Step S410: Output a first control instruction to a reference voltage unit according to an input voltage of the analog-to-digital converter.

[0084] The first control instruction is used to control the reference voltage unit to output a reference voltage to the input terminal of the analog-to-digital converter. The input voltage of the analog-to-digital converter may be a voltage signal input to the input terminal of the analog-to-digital converter by an external device. The reference voltage output by the reference voltage unit may be adjustable. For example, the reference voltage may be determined based on the input voltage of the analog-to-digital converter, and the reference voltage may match the input voltage.

[0085] For example, the control unit can determine the reference voltage to be output by the reference voltage unit based on the input voltage of the analog-to-digital converter, thereby generating a first control instruction. By outputting the first control instruction to the reference voltage unit, the reference voltage unit can be accurately controlled to output the reference voltage to the input terminal of the analog-to-digital converter. The reference voltage can compensate for the input voltage of the input terminal of the analog-to-digital converter, and the compensated input voltage can be input to the second input terminal of the comparison module.

[0086] Step S420: receiving the output voltage of the comparison module, and outputting a second control instruction to the voltage calibration unit according to the output voltage.

[0087] The second control instruction is used to control the voltage calibration unit to output a reference voltage to the first input terminal of the comparison module. The output voltage of the comparison module may be a voltage signal transmitted from the output terminal of the comparison module to the input terminal of the control unit. The reference voltage output by the voltage calibration unit may be adjustable, for example, the reference voltage may be determined based on the output voltage of the comparison module.

[0088] Exemplarily, the voltage calibration unit outputs a reference voltage to the first input terminal of the comparison module, and the second input terminal of the comparison module receives the compensated input voltage. Furthermore, the output terminal of the comparison module can send the output voltage to the control unit, and the control unit can determine the reference voltage to be output by the voltage calibration unit based on the output voltage of the comparison module, thereby generating a second control instruction. By outputting the second control instruction to the voltage calibration unit, the voltage calibration unit can be accurately controlled to output the reference voltage to the first input terminal of the comparison module. This reference voltage can be used as a reference voltage for the comparison module to calibrate the signal deviation of the analog-to-digital converter, thereby eliminating the impact caused by the signal deviation.

[0089] In one embodiment, outputting a second control instruction to a voltage calibration unit based on the output voltage includes: calculating a difference between a code value of the output voltage and a reference code value, and determining a target output voltage of the voltage calibration unit based on the difference; generating a second control instruction based on the target output voltage, and outputting the second control instruction to the voltage calibration unit.

[0090] It should be noted that the output voltage can be a binary signal, from which the code value of the output voltage can be determined. For example, the code value can be calculated using a preset bit as a unit, thereby calculating the difference between the code value of the output voltage and a reference code value. Based on the difference between the code value of the output voltage and the reference code value, the positive or negative sign of the signal deviation can be determined, thereby adjusting the reference voltage to be output to obtain the target output voltage.

[0091] By calculating the difference between the code value of the output voltage and the reference code value, the target output voltage of the voltage calibration unit is determined, and a corresponding second control instruction is generated and output to the voltage calibration unit, so that the voltage calibration unit can output a voltage value that is a reference voltage of the target output voltage, and can calibrate the signal deviation of the analog-to-digital converter, thereby accurately eliminating the impact caused by the signal deviation.

[0092] For example, when the first input terminal of the comparison module is positive and the second input terminal is negative, the target output voltage of the voltage calibration unit is proportional to the difference. In other words, in this case, if the difference between the output voltage code value and the reference code value is positive, it indicates a positive signal deviation. Therefore, the reference voltage output by the voltage calibration unit needs to be increased to offset the positive deviation.

[0093] For example, when the first input terminal of the comparison module is negative and the second input terminal is positive, the target output voltage of the voltage calibration unit is inversely proportional to the difference. In other words, in this case, if the difference between the output voltage code value and the reference code value is positive, it indicates that the signal deviation is negative. Therefore, the reference voltage output by the voltage calibration unit needs to be reduced to offset the negative deviation.

[0094] In one embodiment, determining a target output voltage of a voltage calibration unit based on a difference value includes: obtaining a mapping table including mappings between a plurality of difference values and their corresponding target output voltages; and determining the target output voltage corresponding to the difference value from the mapping table. The difference value is the difference between a code value of the output voltage and a reference code value.

[0095] It should be noted that the mapping relationship between multiple difference values and their corresponding target output voltages can be recorded to generate the mapping relationship table. In practical applications, the calibration position of the voltage calibration unit can be automatically configured based on the difference between the code value of the ADC output voltage and the reference code value, and different calibration positions can correspond to target output voltages of different voltage values.

[0096] In one embodiment, the method further includes: determining whether the difference between the code value of the output voltage and the reference code value is greater than a preset difference; if the difference between the code value of the output voltage and the reference code value is greater than the preset difference, continuing to execute the step of outputting a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter; if the difference between the code value of the output voltage and the reference code value is less than or equal to the preset difference, outputting the output voltage to the output end of the analog-to-digital converter.

[0097] The signal calibration method provided by the present application is implemented, which outputs a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter, and the first control instruction is used to control the reference voltage unit to output a reference voltage to the input end of the analog-to-digital converter; receives the output voltage of the comparison module, and outputs a second control instruction to the voltage calibration unit according to the output voltage, and the second control instruction is used to control the voltage calibration unit to output a reference voltage to the first input end of the comparison module. The signal deviation of the analog-to-digital converter is evaluated by outputting a reference voltage by the reference voltage unit, and the signal deviation is calibrated by outputting a reference voltage by the voltage calibration unit, thereby eliminating the influence caused by the signal deviation. The structure of the signal calibration module is relatively simple and easy to integrate. Through the self-calibration mechanism, it does not require the consumption of software resources and does not rely on external test signals, thereby greatly improving the efficiency of signal calibration.

[0098] It should be understood that the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0099] It should also be understood that the term "and / or" used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, including these combinations. It should be noted that, in this article, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further limitations, an element defined by the sentence "including a..." does not exclude the presence of other identical elements in the process, method, article or system that includes the element.

[0100] The serial numbers of the embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments. The above description is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.< / n> < / n> < / n> < / n>

Claims

1. A signal calibration module for an analog-to-digital converter, characterized in that: The signal calibration module includes a reference voltage unit, a voltage calibration unit and a control unit; The input end of the reference voltage unit is used to connect to a first voltage source, the output end of the reference voltage unit is used to connect to the input end of the analog-to-digital converter, and the controlled end of the reference voltage unit is connected to the first control end of the control unit; The input end of the voltage calibration unit is used to connect to a second voltage source, the output end of the voltage calibration unit is used to connect to the first input end of the comparison module of the analog-to-digital converter, the controlled end of the voltage calibration unit is connected to the second control end of the control unit; the second input end of the comparison module is connected to the input end of the analog-to-digital converter; The input end of the control unit is used to connect to the output end of the comparison module, and the output end of the control unit is used to connect to the output end of the analog-to-digital converter; The control unit is used to output a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter; the reference voltage unit is used to output a reference voltage to the input end of the analog-to-digital converter according to the first control instruction; The control unit is further configured to output a second control instruction to the voltage calibration unit according to the output voltage of the comparison module; and the voltage calibration unit is configured to output a reference voltage to the first input terminal of the comparison module according to the second control instruction.

2. The signal calibration module according to claim 1, wherein: The reference voltage unit includes a grounding resistor and a voltage dividing unit; The input end of the voltage divider unit is used to connect to the first voltage source, the voltage divider end of the voltage divider unit serves as the output end of the voltage calibration unit, and the controlled end of the voltage divider unit serves as the controlled end of the reference voltage unit; the output end of the voltage divider unit is connected to the first end of the grounding resistor, and the second end of the grounding resistor is grounded.

3. The signal calibration module according to claim 1, wherein: The reference voltage unit includes a grounding resistor and a plurality of voltage dividing units; A first-stage voltage divider unit among the plurality of voltage divider units is used to connect to the first voltage source, an intermediate-stage voltage divider unit among the plurality of voltage divider units is connected to the first-stage voltage divider unit or the intermediate-stage voltage divider unit of the previous stage; a final-stage voltage divider unit among the plurality of voltage divider units is connected to the final intermediate-stage voltage divider unit, and the final-stage voltage divider unit is further connected to the grounding resistor, which is further used for grounding; The controlled ends of the multiple voltage divider units are respectively connected to the first control end of the control unit, and the multiple voltage divider units are also used to connect to the input end of the analog-to-digital converter; the control unit is also used to output a first control instruction to at least one of the voltage divider units according to the input voltage of the analog-to-digital converter, so that the reference voltage unit outputs a reference voltage that matches the input voltage to the input end of the analog-to-digital converter.

4. The signal calibration module according to any one of claims 2 or 3, characterized in that: The voltage dividing unit includes a first resistor and a first switch; The first end of the first resistor serves as an input end of the voltage divider unit and is connected to the first voltage source or the voltage divider unit of the previous stage; The second end of the first resistor serves as the output end of the voltage divider unit and is connected to the ground resistor or the voltage divider unit of the next stage; The first end of the first switch is connected to the second end of the first resistor; The second end of the first switch serves as a voltage dividing end of the voltage dividing unit and is used to be connected to the input end of the analog-to-digital converter.

5. The signal calibration module according to claim 1, wherein: The voltage calibration unit includes a common-mode voltage calibration unit, and the common-mode voltage calibration unit includes a plurality of electronic voltage dividers connected in series or in parallel.

6. The signal calibration module according to claim 1, characterized in that: The control unit includes a controller and a second switch; The first control terminal of the controller is connected to the controlled terminal of the reference voltage unit, and the second control terminal of the controller is connected to the controlled terminal of the voltage calibration unit; the input terminal of the controller is connected to the first terminal of the second switch; The second end of the second switch serves as an input end of the control unit, and is used to connect to the output end of the comparison module; the third end of the second switch serves as an output end of the control unit, and is used to connect to the output end of the analog-to-digital converter; The controller is used to control the second switch to be disconnected during signal calibration and receive the output voltage of the comparison module; the controller is used to control the second switch to be turned on after the signal calibration is completed, so that the second switch outputs the output voltage to the output end of the analog-to-digital converter.

7. An analog-to-digital converter, characterized in that include: Input and output terminals; a comparison module, wherein a second input terminal of the comparison module is connected to an input terminal of the analog-to-digital converter; The signal calibration module according to any one of claims 1 to 6, connected to the input terminal and the output terminal of the analog-to-digital converter, and further connected to the first input terminal and the output terminal of the comparison module; The signal calibration module is used to perform signal calibration on the input voltage of the analog-to-digital converter.

8. The analog-to-digital converter according to claim 7, wherein: The comparison module includes a comparator unit; the positive input terminal of the comparator unit serves as the first input terminal of the comparison module, the negative input terminal of the comparator unit serves as the second input terminal of the comparison module, and the output terminal of the comparator unit serves as the output terminal of the comparison module.

9. An integrated circuit chip, characterized in that: It comprises a substrate and an analog-to-digital converter according to any one of claims 7 to 8, wherein the analog-to-digital converter is arranged on the substrate.

10. A signal calibration method, characterized in that: Applied to the signal calibration module according to any one of claims 1 to 6, the method comprising: outputting a first control instruction to a reference voltage unit according to an input voltage of the analog-to-digital converter, wherein the first control instruction is used to control the reference voltage unit to output a reference voltage to an input terminal of the analog-to-digital converter; An output voltage of the comparison module is received, and a second control instruction is output to the voltage calibration unit according to the output voltage, wherein the second control instruction is used to control the voltage calibration unit to output a reference voltage to the first input terminal of the comparison module.

11. The signal calibration method according to claim 10, wherein: Outputting a second control instruction to the voltage calibration unit according to the output voltage includes: Calculating a difference between the code value of the output voltage and a reference code value, and determining a target output voltage of the voltage calibration unit according to the difference; A second control instruction is generated according to the target output voltage, and the second control instruction is output to the voltage calibration unit.

12. The signal calibration method according to claim 11, characterized in that: In a case where the first input terminal of the comparison module is positive and the second input terminal is negative, the target output voltage of the voltage calibration unit is proportional to the difference; In a case where the first input terminal of the comparison module is negative and the second input terminal is positive, the target output voltage of the voltage calibration unit is inversely proportional to the difference.

13. The signal calibration method according to claim 11, characterized in that: The determining a target output voltage of the voltage calibration unit according to the difference includes: Obtaining a mapping relationship table, the mapping relationship table including mapping relationships between a plurality of difference values and their corresponding target output voltages; A target output voltage corresponding to the difference is determined from the mapping relationship table.

14. The signal calibration method according to any one of claims 10 to 13, characterized in that: The method further comprises: Determining whether a difference between the code value of the output voltage and a reference code value is greater than a preset difference; If the difference between the code value of the output voltage and the reference code value is greater than the preset difference, then continuing to execute the step of outputting a first control instruction to the reference voltage unit according to the input voltage of the analog-to-digital converter; If the difference between the code value of the output voltage and the reference code value is less than or equal to the preset difference, the output voltage is output to the output terminal of the analog-to-digital converter.

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