Device and method for compensating precision of analog-to-digital converter

Abstract

The invention provides a device and method for compensating the precision of an analog-to-digital converter, and belongs to the field of analog-to-digital converter precision compensation. The device comprises a power supply module, a precision compensation module, an analog-to-digital converter and a data processing module, the output end of the power supply module is connected with the input end of the analog-to-digital converter, and the output end of the precision compensation module is connected with the input end of the analog-to-digital converter; the output end of the analog-to-digital conversion module is connected with the input end of the data processing module. The power supply module outputs power to the analog-to-digital converter, the precision compensation module outputs reference voltage to the analog-to-digital converter, the analog-to-digital converter outputs analog-to-digital conversion information to the data processing module, and the data processing module calculates a compensated analog-to-digital conversion value. The precision of the analog-to-digital converter is improved, and errors are reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of analog-to-digital converter accuracy compensation, and in particular, relates to a device and method for compensating the accuracy of an analog-to-digital converter. Background Art

[0002] With the development of the automotive industry, the requirements for the voltage detection accuracy of the analog circuits of automotive instruments are becoming increasingly higher, and the corresponding technical requirements for analog-to-digital converters are gradually being strengthened.

[0003] Chinese Patent 118381506B provides a control method, device, chip and vehicle for multiple analog-to-digital converters, the method comprising: obtaining a mode control instruction for adjusting the working mode of the analog-to-digital converter; when the mode control instruction instructs the analog-to-digital converter to enter a parallel mode, controlling the analog-to-digital converter to receive the same first input signal based on the same sampling clock, and the analog-to-digital converter generates a first output signal based on the first input signal; when the mode control instruction instructs the analog-to-digital converter to enter a serial mode, controlling the analog-to-digital converter to receive the same second input signal in sequence based on different sampling clocks, and the analog-to-digital converter generates a second output signal based on the second input signal.

[0004] The analog-to-digital converter in the above patent does not take into account the problem of analog-to-digital conversion accuracy, which may cause errors in the digital quantity generated by the analog-to-digital converter. Summary of the invention

[0005] The present invention aims to provide a device and method for compensating the accuracy of an analog-to-digital converter, so as to achieve the technical purpose of improving the accuracy of the analog-to-digital converter and reducing errors.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The present invention provides a device for compensating the accuracy of an analog-to-digital converter, comprising a power supply module, an accuracy compensation module, an analog-to-digital converter and a data processing module, wherein the output end of the power supply module is connected to the input end of the analog-to-digital converter, the output end of the accuracy compensation module is connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital conversion module is connected to the input end of the data processing module.

[0008] The power supply module outputs power to the analog-to-digital converter, the accuracy compensation module outputs a reference voltage to the analog-to-digital converter, and the analog-to-digital converter outputs analog-to-digital conversion information to the data processing module.

[0009] The precision compensation module adopts a three-terminal adjustable shunt shunt regulator.

[0010] The voltage reference terminal of the three-terminal adjustable shunt shunt regulator is connected to the analog input terminal of the analog-to-digital converter.

[0011] The analog-to-digital converter includes a plurality of analog input terminals.

[0012] The data processing module adopts a central processing unit.

[0013] The present invention provides a method for compensating the accuracy of an analog-to-digital converter:

[0014] Step 1: The analog-to-digital converter generates an analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator according to its own actual value of the reference voltage and the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator;

[0015] Step 2: The analog-to-digital converter generates an analog-to-digital conversion value of the analog voltage input quantity according to its own actual reference voltage value and the analog voltage input quantity;

[0016] Step three: The analog-to-digital converter inputs the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input into the data processing module. The data processing module calculates the analog-to-digital conversion value after compensation of the analog voltage input based on the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input.

[0017] The actual value of the reference voltage of the analog-to-digital converter is equal to the operating voltage of the analog-to-digital converter.

[0018] When there are multiple analog voltage inputs, the analog-to-digital converter generates analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively, and the data processing module calculates the compensated analog-to-digital conversion values ​​of multiple analog voltage input quantities through the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion values ​​of the multiple analog voltage input quantities.

[0019] The technical effects of the present invention are:

[0020] (1) The present invention replaces the reference voltage of the analog-to-digital converter with the reference voltage of the three-terminal adjustable shunt shunt regulator, thereby improving the accuracy of the analog-to-digital converter and reducing the error.

[0021] (2) The present invention achieves the technical purpose of improving accuracy and reducing errors by adding a precision compensation module without changing the original circuit structure, thereby reducing development costs.

[0022] (3) The analog-to-digital converter of the present invention has multiple analog input terminals, which improves the efficiency of analog-to-digital conversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] This specification includes the following drawings, which show the following contents:

[0024] Figure 1 A logical structure block diagram of a device and method for compensating the accuracy of an analog-to-digital converter according to the present invention;

[0025] Figure 2 A circuit diagram of a device and method for compensating the accuracy of an analog-to-digital converter according to the present invention;

[0026] Figure 1 Marked as: 1. power supply module; 2. precision compensation module; 3. analog-to-digital converter; 4. data processing module. DETAILED DESCRIPTION

[0027] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention and facilitating their implementation.

[0028] The present invention provides a device for compensating the accuracy of an analog-to-digital converter, comprising a power supply module 1, an accuracy compensation module 2, an analog-to-digital converter 3 and a data processing module 4, wherein the output end of the power supply module 1 is connected to the input end of the analog-to-digital converter 3, the output end of the accuracy compensation module 2 is connected to the input end of the analog-to-digital converter 3, and the output end of the analog-to-digital conversion module is connected to the input end of the data processing module. The power supply module 1 outputs power to the analog-to-digital converter 3, the accuracy compensation module 2 outputs a reference voltage to the analog-to-digital converter 3, and the analog-to-digital converter 3 outputs analog-to-digital conversion information to the data processing module.

[0029] The precision compensation module 2 uses a three-terminal adjustable shunt shunt regulator. The voltage reference end of the three-terminal adjustable shunt shunt regulator is connected to the analog input end of the analog-to-digital converter 3. The analog-to-digital converter 3 includes multiple analog input ends. The data processing module uses a central processing unit.

[0030] The present invention provides a method for compensating the conversion accuracy of an analog-to-digital converter 3:

[0031] Step 1: The analog-to-digital converter 3 generates an analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator according to its own actual value of the reference voltage and the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator;

[0032] Step 2: The analog-to-digital converter 3 generates an analog-to-digital conversion value of the analog voltage input quantity according to its own actual reference voltage value and the analog voltage input quantity;

[0033] Step 3: The analog-to-digital converter 3 inputs the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input into the data processing module, and the data processing module calculates the analog-to-digital conversion value of the analog voltage input after compensation according to the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input. The actual value of the reference voltage of the analog-to-digital converter 3 is equal to the working voltage of the analog-to-digital converter 3.

[0034] When there are multiple analog voltage inputs, the analog-to-digital converter 3 generates analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively, and the data processing module calculates the compensated analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively through the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt parallel regulator and the analog-to-digital conversion values ​​of the multiple analog voltage input quantities.

[0035] The following is a detailed description of a device and method for compensating the conversion accuracy of the analog-to-digital converter 3 according to the present invention.

[0036] The present invention discloses a device for compensating the conversion accuracy of an analog-to-digital converter 3, comprising a power supply module 1, an accuracy compensation module 2, an analog-to-digital converter 3 and a data processing module. The power supply module 1 is composed of a power supply and a power supply chip. The power supply provides power, and the power supply chip filters and shields burr interference from a printed circuit board to improve conversion accuracy. The power supply chip adopts an LM1117 chip.

[0037] The precision compensation module 2 adopts a three-terminal adjustable shunt shunt regulator, which is a controllable precision voltage source. In the present invention, the three-terminal adjustable shunt shunt regulator replaces the reference voltage of the analog-to-digital converter 3 with its reference voltage. Since the reference voltage accuracy of the three-terminal adjustable shunt shunt regulator is between ±0.4%, and the reference voltage accuracy of the analog-to-digital converter 3 is between ±3.6%, the present invention replaces the reference voltage of the analog-to-digital converter 3 with the reference voltage of the three-terminal adjustable shunt shunt regulator, which can improve the conversion accuracy of the analog-to-digital converter 3. In the embodiment of the present invention, the model of the three-terminal adjustable shunt shunt regulator is TL431.

[0038] The analog-to-digital converter 3 is used to convert the analog voltage input into a digital quantity. The analog-to-digital converter 3 of the present invention has multiple analog quantity input terminals, which improves the efficiency of analog-to-digital conversion. The data processing module uses a central processing unit to process the analog-to-digital conversion information input by the analog-to-digital converter 3 to obtain the analog-to-digital conversion value of the compensated analog voltage input. The central processing unit in the embodiment of the present invention uses a CS32G020 series chip.

[0039] According to the following Figure 2 The circuit diagram of the present invention describes the connection relationship in detail, and the Vout pin of the power supply chip is connected to the V DDA Port connects to the V REF Pin, the Vout pin of the power supply chip is connected to the FB pin through resistor R1, the FB pin is grounded through resistor R2, and the FB pin is the feedback pin; the cathode of the three-terminal adjustable shunt shunt regulator is connected to the V DDA Port connects to the V REF pin, the cathode of the three-terminal adjustable shunt shunt regulator is connected to the V refpin, three-terminal adjustable shunt shunt regulator V ref The pins are connected to the positive electrode and ground of the three-terminal adjustable shunt shunt regulator through resistor R4. The V ref The pin is connected to the analog input terminal of the analog-to-digital converter 3, which includes multiple analog input terminals, and the output terminal of the analog-to-digital converter 3 is connected to the input terminal of the central processing unit. ref The pin is the voltage reference terminal of the three-terminal adjustable shunt shunt regulator, V REF The pin is the voltage reference terminal of analog-to-digital converter 3.

[0040] The following is a detailed description of a method for compensating the conversion accuracy of an analog-to-digital converter 3 of the present invention: at the beginning of operation, the power supply module 1 provides power to the analog-to-digital converter 3, the actual value of the reference voltage of the analog-to-digital converter 3 is the working voltage of the analog-to-digital converter 3, the analog-to-digital converter 3 receives the reference voltage input from the voltage reference terminal of the three-terminal adjustable shunt shunt regulator, and the analog-to-digital converter 3 generates an analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator according to its own actual value of the reference voltage and the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator. The specific formula is:

[0041]

[0042] ADC1 is the analog-to-digital conversion value of the three-terminal adjustable shunt shunt regulator, V1 is the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator, V REF is the actual value of the reference voltage of the analog-to-digital converter 3, and the coefficient 4095 is determined by the number of bits of the chip of the analog-to-digital converter 3. The number of bits of the chip of the analog-to-digital converter 3 in the present invention is 12 bits.

[0043] The present invention has multiple analog input terminals, one of which is used as an example for explanation; the analog voltage inputs voltage information through the analog input terminal, and the analog-to-digital converter 3 generates an analog-to-digital conversion value of the analog voltage input according to its own actual reference voltage value and the analog voltage input. The specific formula is:

[0044]

[0045] ADC2 is the analog-to-digital conversion value of the second analog voltage input, V2 is the analog voltage input, V REF is the actual value of the reference voltage of the analog-to-digital converter 3.

[0046] The analog-to-digital converter 3 inputs the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input into the data processing module. The data processing module calculates the analog-to-digital conversion value of the compensated analog voltage input according to the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input. The calculation formula is:

[0047]

[0048] Among them, ADC 2.1 is the analog-to-digital conversion value after analog voltage input compensation, the coefficient 2.5 is the theoretical value of the reference voltage of the three-terminal adjustable shunt shunt regulator, and the coefficient 3.3 is the theoretical value of the reference voltage of the analog-to-digital converter 3.

[0049] When there are multiple analog voltage inputs, the analog-to-digital converter 3 generates analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively, and the data processing module calculates the compensated analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively through the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt parallel regulator and the analog-to-digital conversion values ​​of the multiple analog voltage input quantities.

[0050] After calculation by the data processing module, the influence of the actual value of the reference voltage of the analog-to-digital converter 3 on the analog-to-digital conversion of the analog voltage input quantity is eliminated. The accuracy of the analog-to-digital conversion is determined by the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator. Since the error between the actual value and the theoretical value of the reference voltage of the three-terminal adjustable shunt shunt regulator is smaller than that between the actual value and the theoretical value of the reference voltage of the analog-to-digital converter 3, the working accuracy of the analog-to-digital converter 3 can be improved and the error can be reduced.

[0051] The present invention achieves the technical purpose of improving accuracy and reducing errors by adding the accuracy compensation module 2 without changing the original circuit structure, thereby reducing the development cost.

[0052] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A device for compensating the accuracy of an analog-to-digital converter, characterized in that: It includes a power supply module, an accuracy compensation module, an analog-to-digital converter and a data processing module, wherein the output end of the power supply module is connected to the input end of the analog-to-digital converter, the output end of the accuracy compensation module is connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital conversion module is connected to the input end of the data processing module.

2. A device for compensating the accuracy of an analog-to-digital converter as claimed in claim 1, characterized in that: The power supply module outputs power to the analog-to-digital converter, the accuracy compensation module outputs a reference voltage to the analog-to-digital converter, and the analog-to-digital converter outputs analog-to-digital conversion information to the data processing module.

3. The device for compensating the accuracy of an analog-to-digital converter according to claim 1, characterized in that: The precision compensation module adopts a three-terminal adjustable shunt shunt regulator.

4. A device for compensating the accuracy of an analog-to-digital converter as claimed in claim 1 or 3, characterized in that: The voltage reference terminal of the three-terminal adjustable shunt shunt regulator is connected to the analog input terminal of the analog-to-digital converter.

5. The device for compensating the accuracy of an analog-to-digital converter according to claim 1, characterized in that: The analog-to-digital converter includes a plurality of analog input terminals.

6. The device for compensating the accuracy of an analog-to-digital converter according to claim 1, characterized in that: The data processing module adopts a central processing unit.

7. A method for compensating the accuracy of an analog-to-digital converter as claimed in claims 1 to 6, characterized in that: Step 1: The analog-to-digital converter generates an analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator according to its own actual value of the reference voltage and the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator; Step 2: The analog-to-digital converter generates an analog-to-digital conversion value of the analog voltage input quantity according to its own actual reference voltage value and the analog voltage input quantity; Step three: The analog-to-digital converter inputs the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input into the data processing module. The data processing module calculates the analog-to-digital conversion value after compensation of the analog voltage input based on the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion value of the analog voltage input.

8. A method for compensating the accuracy of an analog-to-digital converter as claimed in claim 7, characterized in that: The actual value of the reference voltage of the analog-to-digital converter is equal to the operating voltage of the analog-to-digital converter.

9. A method for compensating the accuracy of an analog-to-digital converter as claimed in claim 7, characterized in that: When there are multiple analog voltage inputs, the analog-to-digital converter generates analog-to-digital conversion values ​​of multiple analog voltage input quantities respectively, and the data processing module calculates the compensated analog-to-digital conversion values ​​of multiple analog voltage input quantities through the analog-to-digital conversion value of the actual value of the reference voltage of the three-terminal adjustable shunt shunt regulator and the analog-to-digital conversion values ​​of the multiple analog voltage input quantities.

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