JP6436105B2 - Abnormality diagnosis device for A / D converter - Google Patents

Description

  The present invention relates to an abnormality diagnosis apparatus for detecting an abnormality of an A / D converter.

  In order to control various operations of a robot or the like, an A / D converter that outputs an input analog signal as a digital signal is used. In order to operate the robot or the like normally, a diagnosis for detecting an abnormality such as a failure of the A / D converter is performed. In this diagnosis, an abnormality of the output signal with respect to the input signal is detected. Patent Document 1 describes a circuit for detecting an abnormality of an A / D converter. This circuit compares a multiplexer having a sequence of analog outputs, an analog-to-digital converter, and a sequence of digital outputs from the analog-to-digital converter with a normal range sequence corresponding to the digital output. And a processor for providing an error output when the number is outside the normal range.

Special table 2007-534272 gazette

According to the circuit described in Patent Document 1, an abnormality of the digital output is detected and an abnormality of the A / D converter is determined. For this reason, the circuit described in Patent Document 1 cannot diagnose and diagnose a failure on the analog input side such as a power supply voltage and a failure of the A / D converter itself that receives the analog input. Therefore, in this circuit, even if there is an abnormality on the analog input side, there is a possibility that the A / D converter side is diagnosed as a failure.
An object of the present invention is to provide an abnormality diagnosis apparatus for an A / D converter that can individually diagnose a failure on the analog input side and a failure on the A / D converter side.

An abnormality diagnosis apparatus for an A / D converter according to the present invention is an abnormality diagnosis apparatus for detecting an abnormality of an A / D converter that outputs a digital signal from an input analog signal,
Determining means for determining whether an output voltage of the digital signal corresponding to the analog signal input with an input voltage is in a normal range and outputting a determination result;
Detecting means for detecting an abnormality of the A / D converter based on the determination result,
The determination means outputs a first determination result for determining whether or not the first output voltage of the first digital signal corresponding to the first analog signal input at the first input voltage is in the first normal range. Outputting a second determination result for determining whether or not the second output voltage of the second digital signal corresponding to the second analog signal input at the second input voltage is in the second normal range;
The detection means compares the first determination result with the second determination result in a state where the first normal range and the second normal range are set to have an overlapping range. An abnormality of the D converter is detected.

  According to the abnormality diagnosis apparatus for an A / D converter according to the present invention, a failure on the analog input side and a failure on the A / D converter side can be individually diagnosed.

It is a block diagram which shows the structure of an abnormality diagnosis apparatus. It is the table | surface which showed the range of the input voltage of the analog signal input. It is the figure which showed the normal range of the output voltage of the digital signal output. It is the flowchart which showed the abnormality diagnosis method by the abnormality diagnosis apparatus. It is the table | surface which showed the diagnostic result. It is the figure which showed the normal range of the output voltage of a digital signal at the time of combining the self-diagnosis function of a microcomputer.

Hereinafter, embodiments of an abnormality diagnosis apparatus for an A / D converter according to the present invention will be described with reference to the drawings.

As shown in FIG. 1, the abnormality diagnosis apparatus 1 is connected to an A / D converter 10. The abnormality diagnosis device 1 may be a circuit inside the A / D converter 10. The A / D converter 10 may be of a type with a built-in processor or an external IC. A / D converter 10, the analog signal _V A n inputted from the input side 11: outputs a digital signal _{V D} n corresponding to (n positive integer) from the output side 12. Analog signal V _{A n} is inputted with an input voltage having a voltage value of the analog. Digital signal V _{D n} is output with an output voltage corresponding to the input voltage of the analog signal V _{A n.} The A / D converter 10 has a general configuration, and a description of the internal configuration and the like is omitted.

The abnormality diagnosis apparatus 1 includes a determination unit 2 connected to the output side 12 and a detection unit 6 connected to the determination unit 2. The determination unit 2 receives the digital signal V _D n, determines whether or not the output voltage of the digital signal V _D n corresponding to the analog signal V _A n is in a normal range, and outputs a determination result. Examples of the analog signal _{V A} n input to the A / D converter 10 is shown in FIG. 2 (n = 1~5). Each of the input voltage of the analog signal V _{A n} in the normal lies within the respective range up Min～max.

As shown in FIG. 3, the digital signal V _{D n} to be input to the determination unit 2 has an output voltage corresponding to the analog signal V _{A n} input. The digital signal V _D n is adjusted so that the output voltage falls within the normal range Vn. The voltage value of the output voltage of the digital signal V _D n is output as a numerical value of the digital signal as described in the A / D conversion table. The normal ranges Vn and Vn + 1 (n = 1 to 4) are set so that an overlapping range Dn occurs. The judging means 2 judges whether or not the output voltage (A / D conversion value) of the digital signal V _D n is within the normal range Vn. The determination unit 2 outputs a determination result to the detection unit 6. The determination unit 2 outputs n determination results to the detection unit 6.

The detection means 6 detects an abnormality of the A / D converter 10 based on the determination result. The detection means 6 detects whether the input side 11 is abnormal or the A / D converter 10 is abnormal based on two consecutive determination results. In the abnormality detection, the abnormality is determined by the output voltages of two different digital signals V _D n and V _D n + 1 (n = 1 to 4).

For example, the determination unit 2 determines a first determination result for determining whether or not the first output voltage of the digital signal V _D 1 corresponding to the analog signal V _A 1 input with the first input voltage is in the normal range V1. Output. Then, the judging means 2 outputs a second judgment result for judging whether or not the second output voltage of the second digital signal corresponding to the analog signal V _A 1 inputted with the second input voltage is in the normal range V2. To do. Thereafter, the detection means 6 compares the first determination result and the second determination result to detect an abnormality of the A / D converter 10. A specific abnormality detection method process will be described below.

As shown in FIG. 4, in the abnormality diagnosis apparatus 1, the determination unit 2 acquires the digital signal V _D n from the A / D converter 10 (S100). The determination unit 2 determines whether or not the output voltage (A / D conversion value) of the digital signal V _D n is within the normal range Vn (S101). When the determination unit 2 determines that the output voltage (A / D conversion value) of the digital signal V _D n is within the normal range Vn (S101: Yes), the determination unit 2 outputs the determination result to the detection unit 6. The detection means 6 compares the determination result corresponding to one input with the determination result corresponding to another input (S102). Detecting means 6, another determination result, that is, when the A / D conversion values corresponding to other different input is determined to be within the normal range (S102: Yes), different analog signal V _{A n} are each input It is determined that the A / D converter 10 is correct and has no abnormality: R1 (S103).

If the detection means 6 determines in step 102 that other determination results, that is, A / D conversion values corresponding to other different inputs are not within the normal range (S102: No), It is determined that a different input is abnormal: R2 (S104). When the determination unit 2 determines in step 101 that the output voltage (A / D conversion value) of the digital signal V _D n is not within the normal range Vn (S101: No), the determination result is output to the detection unit 6. To do. The detection unit 6 compares the determination result corresponding to one input with the determination result corresponding to another input (S105).

When the detection means 6 determines that another determination result, that is, an A / D conversion value corresponding to another different input is within the normal range (S105: Yes), the input 1 is determined to be abnormal: R3 ( S106). The input abnormality of 1 is, for example, open, short, or drift in the circuit. The type of abnormality is determined by how the digital signal V _D n changes. For example, the determination can be made based on a phenomenon such as sticking up and down, gradually increasing or decreasing, vibration in a certain period, and the like indicated by the voltage value of the output voltage of the digital signal V _D n.

If the detection means 6 determines in step 105 that other determination results, that is, A / D conversion values corresponding to other different inputs are not within the normal range (S105: No), the A / D converter 10 is abnormal. Is determined: R4 (S107). In the abnormality diagnosis apparatus 1, the output voltage (A / D conversion value) of each digital signal V _D n corresponding to each analog input can be acquired by the loop of step S108 and step 109. The above diagnostic results R1 to R4 are shown in FIG. Here, the case where the voltage value of the output voltage of the digital signal V _D n is within the normal range is described as ◯, and the case where the voltage value is not within the normal range is described as ×. The detection means 6 can diagnose an abnormality of the A / D converter 10 based on this table.

As described above, according to the abnormality diagnosis device 1, the abnormality diagnosis of the A / D converter 10, whether the value of the input voltage of the analog signal V _{A n} inputted from the input side 11 that is abnormal, and A / D It is possible to individually detect whether there is an abnormality in the converter 10 itself. Moreover, according to the abnormality diagnosis apparatus 1, the type of failure of the A / D converter 10 can also be determined. According to the abnormality diagnosis apparatus 1, the operating rate of a device such as a robot in which the A / D converter 10 is incorporated can be improved, the number of replacements of the A / D converter 10 can be reduced, and the maintainability can be improved. .

  The abnormality diagnosis method for the A / D converter 10 by the abnormality diagnosis apparatus 1 described above may be realized by using a semiconductor processing apparatus including an ASIC (Application Specific Integrated Circuit). Further, these processes may be realized by causing a computer system including at least one processor (eg, microprocessor, MPU, DSP (Digital Signal Processor)) to execute a program. Specifically, one or a plurality of programs including an instruction group for causing the computer system to perform an algorithm related to the transmission signal processing or the reception signal processing may be created, and the programs may be supplied to the computer.

  These programs can be stored and supplied to a computer using various types of non-transitory computer readable media. Non-transitory computer readable media include various types of tangible storage media.

  Examples of non-transitory computer-readable media include magnetic recording media (for example, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (for example, magneto-optical disks), CD-ROM (Read Only Memory), CD-R ( (Registered trademark), CD-R / W (registered trademark), semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)).

  The program may also be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, as shown in FIG. 6, the abnormality diagnosis apparatus 1 may be combined with a self-diagnosis function provided in a microcomputer or the like. A microcomputer equipped with a self-diagnosis function also includes a voltage generator inside. At this time, the normal value range for each input power supply may be set in accordance with a range in which the microcomputer can perform self-diagnosis.

DESCRIPTION OF SYMBOLS 1 Abnormality diagnosis apparatus 2 Judgment means 6 Detection means 10 Converter 11 Input side 12 Output side VAn Analog signal VDn Digital signal Vn Normal range

Claims (1)

An abnormality diagnosis device for detecting an abnormality of an A / D converter that outputs a digital signal from an input analog signal,
Determining means for determining whether an output voltage of the digital signal corresponding to the analog signal input with an input voltage is in a normal range and outputting a determination result;
Detecting means for detecting an abnormality of the A / D converter based on the determination result,
The determination means outputs a first determination result for determining whether or not the first output voltage of the first digital signal corresponding to the first analog signal input at the first input voltage is in the first normal range. Outputting a second determination result for determining whether or not the second output voltage of the second digital signal corresponding to the second analog signal input at the second input voltage is in the second normal range;
The detection means compares the first determination result with the second determination result in a state where the first normal range and the second normal range are set to have an overlapping range. Detect D converter abnormality,
A / D converter abnormality diagnosis device.

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