WO2018171281A1 - Analogue-to-digital converter and automobile - Google Patents

Abstract

Provided are an analogue-to-digital converter and an automobile, wherein the analogue-to-digital converter comprises: a first conversion circuit, which is used for converting a sensor voltage signal input by a first input end into a first digital signal and outputting same by means of a first output end; a second conversion circuit, which is used for converting a sensor voltage signal input by a second input end into a second digital signal and outputting same by means of a second output end, wherein the first input end is connected to the second input end; and a control unit, which respectively acquires the first digital signal output by the first output end and the second digital signal output by the second output end, and is used for outputting a pre-set fault signal when an absolute value of the difference between a voltage value represented by the first digital signal and a voltage value represented by the second digital signal is greater than or equal to a first pre-set value.

Description

Analog to digital converter and automobile

Cross-reference to related applications

Priority is claimed on Japanese Patent Application No. 201710172851.8, filed on Jan. 22,,,,,,,,,

Technical field

The present disclosure relates to the field of analog-to-digital conversion technologies, and in particular, to an analog-to-digital converter and an automobile.

Background technique

Functional Safety The ISO 26262 standard is based on IEC61508 and is written to meet the needs of specific electronic and electrical systems on road vehicles. Safety is one of the key issues in the future development of automobiles. Not only in the field of driving assistance and power drive, but also in the field of vehicle dynamic control and active and passive safety systems, new functions are increasingly reaching the field of system safety engineering. The development and integration of these features will strengthen the need for safety-related system development processes and require proof of meeting all reasonable system safety objectives. As technology becomes more complex, software content and mechatronic applications continue to increase, the risks from system failures and random hardware failures increase.

Analog-to-Digital Converter (ADC) is the key input module of the controller. The correctness of the data collected by the ADC of the analog-to-digital converter directly affects the security of the control system. It is also the focus of functional safety. Functional safety ISO 26262 standard has strict detection requirements for analog-to-digital converter ADC stuck, drift, oscillation, short-circuit between signal lines, etc. Traditional analog-to-digital converter ADC acquisition does not consider hardware failure, software Data validity is usually only filtered, so when the ADC of the analog-to-digital converter fails, the system will use invalid data for calculation, and it is very likely that a security incident will occur.

Summary of the invention

The technical problem to be solved by the embodiments of the present disclosure is to provide an analog-to-digital converter and a vehicle, which are used to increase the reference group to collect the same signal for comparison by redundant design, thereby reducing the possibility of damage caused by hardware failure.

The present disclosure provides, in some embodiments, an analog-to-digital converter, including: a first conversion circuit, configured to convert a sensor voltage signal input by the first input terminal into a first digital signal, and output through the first output terminal; a second conversion circuit, configured to convert a sensor voltage signal input by the second input terminal into a second digital signal, and output through the second output end; wherein the first input end is connected to the second input end; a control unit, respectively acquiring a first digital signal output by the first output end and a second digital signal output by the second output end, for using a voltage value represented by the first digital signal and the second digital When the absolute value of the difference of the voltage values indicated by the signal is greater than or equal to the first preset value, the first preset fault signal is output.

In some embodiments, the first conversion circuit is further configured to convert a reference voltage signal input by the third input terminal into a third digital signal and output through the third output terminal; the second conversion circuit is further configured to The reference voltage signal input by the fourth input terminal is converted into a fourth digital signal and output through the fourth output terminal, wherein the third input terminal is connected to the fourth input terminal; the control unit is further used for And outputting a second preset fault signal when an absolute value of a difference between the voltage value represented by the third digital signal and the voltage value indicated by the fourth digital signal is greater than or equal to a second preset value.

In some embodiments, the control unit is further configured to: when an absolute value of a difference between the voltage value represented by the first digital signal and the voltage value represented by the second digital signal is less than a first preset value, and Outputting the first digital signal as a mode of the sensor voltage signal when an absolute value of a difference between a voltage value represented by the third digital signal and a voltage value represented by the fourth digital signal is less than a second predetermined value Number conversion result signal.

In some embodiments, the analog to digital converter further includes: a first storage unit respectively connected to the first output end and the third output end, the first storage unit is configured to store the first storage unit a digital signal and the third digital signal.

In some embodiments, the control unit is coupled to the first storage unit and acquires the first digital signal and the third number stored in the first storage unit by the first storage unit signal.

In some embodiments, the analog to digital converter further includes: a second storage unit respectively connected to the second output end and the fourth output end, the second storage unit configured to store the second a digital signal and the fourth digital signal.

In some embodiments, the control unit is coupled to the second storage unit and acquires the third digital signal and the fourth number stored in the second storage unit by the second storage unit signal.

In some embodiments, the first predetermined value ranges from 0.8% of the range of the sensor that inputs the sensor voltage signal to 1.2% of the range of the sensor.

In some embodiments, the second preset value ranges from 0.8% of the voltage value of the reference voltage to 1.2% of the voltage value of the reference voltage.

Embodiments of the present disclosure also provide an automobile including an analog to digital converter as described above.

Compared with the related art, an analog-to-digital converter and an automobile provided by the embodiments of the present disclosure have at least the following beneficial effects: the embodiment of the present disclosure adds a conversion circuit as a reference group by redundant design, and compares by collecting the same signal. Analysis prevents the conversion circuit used for output from being faulty due to faults, etc., reducing the possibility of damage due to hardware failure. At the same time, the embodiment of the present disclosure can also add a reference voltage, separately collect and convert the reference voltage signal and compare to prevent the output digital signal from being wrong due to the error of the reference voltage collection, thereby further reducing the damage caused by the hardware failure failure. possibility.

DRAWINGS

1 is a schematic structural diagram of an analog-to-digital converter according to an embodiment of the present disclosure;

2 is a schematic structural diagram of an analog to digital converter according to an embodiment of the present disclosure.

detailed description

The technical problems, the technical solutions, and the advantages of the present invention will be more clearly described in conjunction with the accompanying drawings and specific embodiments. In the following description, specific details such as specific configurations and components are provided only to assist in a comprehensive understanding of the embodiments of the present disclosure. It will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the disclosure. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

It is to be understood that the phrase "one embodiment" or "an embodiment" or "an" or "an" Thus, "in one embodiment" or "in an embodiment" or "an" In addition, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Referring to FIG. 1 to FIG. 2, an embodiment of the present disclosure provides an analog-to-digital converter, including: a first conversion circuit 1 configured to convert a sensor voltage signal input by a first input terminal into a first digital signal, and pass the An output terminal is configured to convert the sensor voltage signal input by the second input terminal into a second digital signal and output the second output terminal; wherein the first input end and the first The two input terminals are connected; the control unit 3 respectively obtains the first digital signal output by the first output end and the second digital signal output by the second output end, for the voltage represented by the first digital signal When the absolute value of the difference between the value and the voltage value indicated by the second digital signal is greater than or equal to the first preset value, the first preset fault signal is output.

In the embodiment of the present disclosure, the second conversion circuit is added as a reference comparison group, and the first conversion circuit and the second conversion circuit simultaneously receive the voltage signal output by the sensor and convert it into a digital signal, and the control unit will pair the first conversion circuit. Comparing the voltage value indicated by the outputted first digital signal with the voltage value represented by the second digital signal output by the second conversion circuit, when the absolute value of the difference between the two is greater than or equal to the first preset value (according to the experiment Calibration is performed), at this time, the voltage values collected by the two are quite different (beyond the allowable error range), the first conversion circuit or the second conversion circuit may be faulty, and the voltage signal collected at this time is not accurate, if the output is wrong The voltage signal can cause subsequent control errors and cause danger. Therefore, at this time, the control unit outputs a first failure signal to notify other components or the upper control unit analog-to-digital converter ADC to malfunction.

Through the redundant design, the embodiment of the present disclosure adds a conversion circuit as a reference group, and compares and analyzes by collecting the same signal, thereby preventing the conversion circuit for output from being faulty due to failure, and reducing the possibility of damage caused by hardware failure. . At the same time, the comparison group added by the embodiment of the present disclosure is a separate conversion circuit, which avoids the common cause failure.

It should be noted that the analog-to-digital converter of the embodiment of the present disclosure is not limited to analog-to-digital conversion by using a conversion circuit, and other conversion methods are also possible.

Referring to FIG. 2, in an analog-to-digital converter according to an embodiment of the present disclosure, the first conversion circuit 1 is further configured to convert a reference voltage signal input by the third input terminal into a third digital signal, and pass through the third output end. The second conversion circuit 2 is further configured to convert the reference voltage signal input by the fourth input terminal into a fourth digital signal, and output through the fourth output end, wherein the third input end and the fourth The control unit 3 is further configured to: when an absolute value of a difference between a voltage value represented by the third digital signal and a voltage value represented by the fourth digital signal is greater than or equal to a second preset value When the second preset fault signal is output.

In the analog-to-digital conversion, the analog-to-digital converter converts the collected voltage signal into a digital signal, which needs to be performed according to the reference voltage. At this time, if the reference voltage is collected incorrectly, the voltage value represented by the digital signal after the analog-to-digital conversion is not collected. The voltage value will cause subsequent use, control errors and cause danger. Therefore, in the embodiment of the present disclosure, the first conversion circuit and the second conversion circuit are also used to simultaneously collect a provided reference voltage, wherein the voltage provided by the reference voltage source is known, for example, providing a reference voltage of 2.5V. The first conversion circuit and the second conversion circuit simultaneously collect the reference voltage, and when the control unit determines that the error of the two is within the allowable range, it can be determined that the acquisition reference voltage is correct. When the error of the two is out of the allowable range (when the absolute value of the difference is greater than or equal to the second preset value, the second preset value may be pre-calibrated according to the experiment), the second preset fault signal is output to inform the other The component or upper control component analog-to-digital converter ADC has failed and the current fault has failed for the acquisition reference voltage.

In the embodiment of the present disclosure, a reference voltage is added, and the reference voltage signal is separately collected, converted, and compared to prevent an error in the output of the reference voltage due to a fault in the acquisition of the reference voltage, thereby further reducing the possibility of damage due to hardware failure. .

The control unit 3 is further configured to: when an absolute value of a difference between a voltage value represented by the first digital signal and a voltage value represented by the second digital signal is less than a first preset value, and the Outputting the first digital signal as an analog-to-digital conversion result of the sensor voltage signal when an absolute value of a difference between a voltage value represented by the three digital signals and a voltage value represented by the fourth digital signal is less than a second predetermined value signal.

When the voltage signal collected by the first conversion circuit and the second conversion circuit for the sensor voltage and the voltage signal collected by the reference voltage are within the error tolerance range, it can be determined that the first conversion circuit has not failed, and the first conversion can be performed at this time. The digital signal output after circuit conversion is used by other components.

Referring to FIG. 2, in an analog-to-digital converter according to an embodiment of the present disclosure, the analog-to-digital converter further includes: a first storage unit 4 respectively connected to the first output end and the third output end, The first storage unit 4 is configured to store the first digital signal and the third digital signal.

The control unit 3 is connected to the first storage unit 4, and acquires the first digital signal and the third number stored in the first storage unit 4 through the first storage unit 4. signal.

In some embodiments, the analog to digital converter further includes: a second storage unit 5 connected to the second output end and the fourth output end, respectively, the second storage unit 5 is configured to store the a second digital signal and the fourth digital signal.

The control unit 3 is connected to the second storage unit 5, and acquires the third digital signal and the fourth number stored in the second storage unit 5 through the second storage unit 5. signal.

In this embodiment, the storage unit is further configured to store the digital signals converted by the first conversion circuit and the second conversion circuit, and the control unit may directly connect with the first storage unit and the second storage unit and call the internal storage thereof. Digital signal data. At the same time, when the control unit determines that the first conversion circuit has not failed (ie, the two sets of voltage acquisition are within the error tolerance range), no fault signal is generated to the outside, and the external device can be connected to the first storage unit at this time, and The first digital signal stored by the first storage unit is directly called when needed (the remaining digital signals are used for comparison. In the embodiment, when the fault is not sent, that is, when the analog-to-digital converter is normal, only the first conversion circuit is used. Digital signal after converting the sensor voltage).

It should be noted that the memory cells shown in the drawings are all independent of the conversion circuit. This is only one embodiment of the present disclosure. In another embodiment of the present disclosure, the memory cells shown may also be disposed in the conversion circuit. Internally, and not limited to circuit conversion, it may also be internal to the memory cell setting and conversion module (this is the same function as the conversion circuit described above for converting a voltage signal into a digital signal).

In an analog-to-digital converter according to an embodiment of the present disclosure, the first preset value ranges from 0.8% of the range of the sensor that inputs the sensor voltage signal to 1.2% of the range of the sensor.

In some embodiments, the second preset value ranges from 0.8% of the voltage value of the reference voltage to 1.2% of the voltage value of the reference voltage.

In this embodiment, a reference embodiment is provided for the range of values of the first preset value and the second preset value. In an embodiment, the first preset value is preferably 1% of the range of the sensor, that is, when the difference between the voltage values collected by the two channels is within 1% of the range of the sensor, the error of the acquisition may be considered as permitted. Within this range, the conversion circuit is working properly. The second preset value is preferably 1% of the voltage value of the reference voltage, that is, when the difference between the two collected reference voltage values is within 1% of the voltage value of the reference voltage, the error of the acquisition may be considered to be within an allowable range. At this point, the conversion circuit works normally.

In the analog-to-digital converter of an embodiment of the present disclosure, taking the ADC module of the Infineon chip TC234 as an example, it is assumed that a safe sensor voltage signal needs to be collected, and the following failure analysis is performed:

The above is the failure and the result that may occur when the existing analog-to-digital speed is obtained. The analog-to-digital converter of the embodiment of the present disclosure can detect the failure of the conversion circuit (conversion module) when the above-mentioned failure occurs, that is, the first conversion circuit occurs. In the above fault, by comparing and analyzing the voltage values collected by the second conversion circuit, it is found that the first conversion circuit generates a failure, thereby avoiding safety problems caused by the use of erroneous data.

Embodiments of the present disclosure provide an automobile including an analog to digital converter as described above.

In summary, the embodiment of the present disclosure increases the conversion circuit as a reference group by using redundant design, and compares and analyzes the same signal to prevent the conversion circuit for output from being faulty due to faults, and reduces the damage caused by hardware failure. The possibility. At the same time, the embodiment of the present disclosure can also add a reference voltage, separately collect and convert the reference voltage signal and compare to prevent the output digital signal from being wrong due to the error of the reference voltage collection, thereby further reducing the damage caused by the hardware failure failure. possibility.

It should also be noted that, in this context, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying such entities or operations. There is any such actual relationship or order between them. Moreover, the terms "including", "comprising" or "comprising" or "comprising" are intended to encompass a non-exclusive inclusion.

The above is a preferred embodiment of the present disclosure, and it should be noted that those skilled in the art can also make several improvements and refinements without departing from the principles of the present disclosure. It should also be considered as the scope of protection of the present disclosure.

Claims (10)

An analog to digital converter comprising: a first conversion circuit, configured to convert a sensor voltage signal input by the first input terminal into a first digital signal, and output through the first output end; a second conversion circuit, configured to convert a sensor voltage signal input by the second input terminal into a second digital signal, and output through the second output end; wherein the first input end is connected to the second input end; a control unit, respectively acquiring a first digital signal output by the first output end and a second digital signal output by the second output end, for using a voltage value represented by the first digital signal and the second digital When the absolute value of the difference of the voltage values indicated by the signal is greater than or equal to the first preset value, the first preset fault signal is output. The analog-to-digital converter according to claim 1, wherein the first conversion circuit is further configured to convert a reference voltage signal input by the third input terminal into a third digital signal, and output the third output terminal; The second conversion circuit is further configured to convert the reference voltage signal input by the fourth input terminal into a fourth digital signal, and output through the fourth output end, wherein the third input end is coupled to the fourth input end connection; The control unit is further configured to: when the absolute value of the difference between the voltage value represented by the third digital signal and the voltage value represented by the fourth digital signal is greater than or equal to a second preset value, output a second pre-pre Set the fault signal. The analog-to-digital converter according to claim 2, wherein said control unit is further configured to: when an absolute value of a difference between a voltage value represented by said first digital signal and a voltage value represented by said second digital signal Outputting the first digital signal when the absolute value of the difference between the voltage value indicated by the third digital signal and the voltage value indicated by the fourth digital signal is less than the second preset value As an analog to digital conversion result signal of the sensor voltage signal. The analog-to-digital converter according to claim 2, wherein said analog-to-digital converter further comprises: a first storage unit respectively connected to said first output terminal and said third output terminal, said first storage The unit is configured to store the first digital signal and the third digital signal. The analog-to-digital converter according to claim 4, wherein said control unit is connected to said first storage unit, and acquires said first one stored in said first storage unit by said first storage unit a digital signal and the third digital signal. The analog-to-digital converter according to claim 2, wherein said analog-to-digital converter further comprises: a second storage unit respectively connected to said second output terminal and said fourth output terminal, said second storage The unit is configured to store the second digital signal and the fourth digital signal. The analog-to-digital converter according to claim 6, wherein said control unit is connected to said second storage unit, and said third storage stored in said second storage unit is obtained by said second storage unit a digital signal and the fourth digital signal. The analog-to-digital converter of claim 1, wherein the first predetermined value ranges from 0.8% of a range of sensors input the sensor voltage signal to 1.2% of a range of the sensor. The analog-to-digital converter according to claim 2, wherein the second preset value ranges from 0.8% of the voltage value of the reference voltage to 1.2% of the voltage value of the reference voltage. An automobile comprising the analog to digital converter of any one of claims 1 to 9.

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