JP2013225781A - A/d conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an A/D conversion device that dispenses with any further A/D converters and has a fault diagnosis function added without employing additional circuits.SOLUTION: In an A/D conversion device 10 having an A/D converter 1 for converting an analog electrical quantity of objects 4, 5 to be detected to a digital quantity, switching circuits 3a, 3b for connecting a plurality of analog electrical quantities to the A/D converter 1, and control means 2 for controlling the switching circuits 3a, 3b independently of each other, the control means 2 generates a first mode in which analog electrical quantities of the objects 4, 5 are independently output to the A/D converter 1 one by one, a second mode in which two or more analog electrical quantities of the objects 4, 5 are simultaneously output to the A/D converter 1, and a third mode in which none of the analog electrical quantities of the objects 4, 5 are output, and acquires individual A/D conversion values of the objects 4, 5 in the first mode and detects an anomaly in the device in the second mode and the third mode.

Description

  The present invention relates to an A / D converter for converting an analog quantity into a digital quantity.

  Conventionally, there has been a CPU having a plurality of A / D converters for converting an analog quantity into a digital quantity that can be used by a CPU. In recent years, the number of analog signals input by the CPU in one system has increased, and the absolute number of A / D converters (A / D ports in the CPU) is insufficient. Therefore, a method has been adopted in which information input to the A / D converter is selectively switched using an interface circuit. (For example, see Patent Document 1)

JP 2007-333574 A

  The usage pattern of the A / D converter disclosed in Patent Document 1 is configured to selectively switch a plurality of pieces of information to be input by a switch and take them into a microprocessor. According to this configuration, the number of input information can be increased without increasing the number of A / D converters. However, such a conventional apparatus simply suppresses the number of A / D converters, and in the system, a switch for switching input information is added. In this case, an additional circuit must be provided separately.

  An object of the present invention is to provide an A / D conversion device to which a failure diagnosis function can be added without increasing the number of A / D converters and without providing an additional circuit.

  In order to solve the above problems, an A / D converter according to the present invention includes an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of analogs in the A / D converter. In an A / D conversion device comprising a switching circuit for connecting an electric quantity and a control means for independently controlling the switching circuit, the control means independently converts the analog electric quantity of the object one by one. The first mode for outputting to the A / D converter, the second mode for outputting two or more analog electric quantities of the object to the A / D converter at the same time, and not outputting all the analog electric quantities of the object A third mode is generated, A / D conversion values of the respective objects are individually acquired in the first mode, and an apparatus abnormality is detected in the second mode and the third mode.

  According to the A / D converter of the present invention, a large number of analog electric signals to be captured can be sequentially converted into digital signals by the A / D converter without increasing the number of A / D converters. In addition, no additional circuit is required, and a fault diagnosis function can be easily added.

1 is a block diagram of an A / D conversion device according to Embodiment 1 of the present invention. 1 is a circuit diagram of an A / D converter according to Embodiment 1 of the present invention. It is a figure which shows the time chart explaining operation | movement of the A / D converter by Embodiment 1 of this invention. It is a circuit diagram of the A / D conversion device by Embodiment 2 of this invention. It is a figure which shows the time chart explaining operation | movement of the A / D converter by Embodiment 2 of this invention. It is a figure which shows another time chart explaining operation | movement of the A / D converter by Embodiment 2 of this invention. It is a circuit diagram of the A / D conversion device by Embodiment 3 of this invention.

  Preferred embodiments of an A / D converter according to the present invention will be described below with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a block diagram of an A / D converter according to Embodiment 1 of the present invention. In FIG. 1, in the A / D converter 10, the control unit 2 supplies the analog electric quantities of the first object 4 and the second object 5 to the A / D converter 1 via the switching circuit 3. It can be controlled independently and output.

  FIG. 2 is a circuit diagram of the A / D converter 10 and shows a state in which the CPU 6 incorporates the A / D converter 1. The CPU 6 has an A / D port (A / D # 1) 6a and normal first and second output ports (P1, P2) 6b and 6c. The A / D port 6a is connected to the first and second objects 4 and 5 via first and second switching circuits 3a and 3b controlled by the first and second output ports 6b and 6c. The electric signals to be output are output through the first and second series resistors 7a and 7b, respectively.

  The first and second objects 4 and 5 generate electrical signals that change independently from each other, and in response to the ON operation of the connected switching circuit 3a or switching circuit 3b, the respective signals are A / It is transmitted to the D port 6a. In addition to the A / D port 6a, a pull-up resistor 8 and a capacitor 9 are connected to the power supplies Vcc and GND, respectively, at the common terminals of the first and second switching circuits 3a and 3b. It is configured.

  Next, as shown in the above circuit, an example in which two objects of the first and second objects 4, 5 are connected to one A / D port 6a will be described. The operation of the A / D conversion device 10 according to the first form will be described.

  FIG. 3 is a time chart for explaining the operation of the A / D conversion apparatus 10 according to the first embodiment. In FIG. 3, reference numeral A1 indicates the operating state of the second output port 6c, and reference numeral B1 indicates the operating state of the first output port 6b along the time axis t. Reference C1 indicates the input status of the A / D port 6a.

  First, paying attention to t2 to t3, the second output port 6c = Low and the first output port 6b = high. This is such that the second switching circuit 3b connected to the second output port 6c is turned off and the first switching circuit 3a connected to the first output port 6b is turned on. By turning on only the first switching circuit 3a, the signal of the first object 4 is input to the A / D port 6a through the voltage dividing circuit formed by the first series resistor 7a and the pull-up resistor 8. Only the signal of the first object 4 is taken into the CPU 6.

  Next, paying attention to t3 to t4, as described above, only the signal of the second object 5 is input to the A / D port 6a by turning on only the second switching circuit 3b, and the second The voltage is input to the A / D port 6a through the voltage dividing circuit formed by the series resistor 7b and the pull-up resistor 8, and only the signal of the second object 5 is taken into the CPU 6.

  By these two controls, signals generated by the first and second objects 4 and 5 are independently input to one A / D port 6a, and the CPU 6 can acquire the value. The above is what the conventional apparatus has implemented.

  Next, the A / D conversion apparatus 10 according to the first embodiment uses the same circuit before or before the input of the conventional apparatus, and performs fault diagnosis by adding another simple control. is there.

  First, from t1 to t2, both the first and second output ports 6b and 6c are set to Low, both the first and second switching circuits 3a and 3b are turned off, and the first and second objects 4 and 5 The signal is not connected to the A / D port 6a. In this state, only the pull-up resistor 8 is connected, so that almost the same voltage as the power source Vcc to which the other pull-up resistor 8 is connected is input to the A / D port 6a. If the apparatus is normal, the voltage of the power supply Vcc is input. If a voltage other than the power supply Vcc is input, it can be determined that the apparatus is in an abnormal state. That is, the pull-up resistor 8 is opened, the first switching circuit 3a or the second switching circuit 3b is short-circuited, at least one of the first and second output ports 6b and 6c is defective in H fixation, or A / There is a possibility that the D converter 1 is abnormal, and it is in a failure detection state.

  Next, from t4 to t5, the first and second output ports 6b and 6c are both set to High, the first and second switching circuits 3a and 3b are both kept on, and the first and second objects 4 and 5 are turned on. The signal inputs from are connected together. In this case, a combined voltage dividing circuit formed by the pull-up resistor 8, the first series resistor 7a connected to the first object 4, and the second series resistor 7b connected to the second object 5 as well. Thus, the combined voltage of the signals from the first and second objects 4 and 5 is input to the A / D port 6a. If the switching operation from t1 to t5 is sufficiently fast with respect to the change of the signal generated by the first object object 4 and the second object 5, the first operation is performed at t2 to t3 and t3 to t4. Since the signals of the target object 4 and the second target object 5 are captured and the constants of the combined voltage dividing circuit are known, the validity of the combined voltage can be confirmed.

  That is, the open / short / resistance abnormality of the pull-up resistor 8, the first series resistor 7a, the second series resistor 7b, the first switching circuit 3a, or the second switching circuit based on the voltage identification at t4 to t5. There is a possibility that an open failure 3b, at least one of the first and second output ports 6b and 6c may be an L fixing failure, or an abnormality of the A / D converter 1, and is in a failure detection state.

  That is, when the voltage input to the A / D port 6a at t1 to t2 is a voltage other than the power supply Vcc, or the voltages input to the A / D port 6a at t4 to t5 are t2 to t3 and t3 to t4. If the calculation based on the signal capture values of the first and second objects 4 and 5 is not consistent, it is determined that the device is abnormal. Therefore, without complicating the configuration of the switching circuits 3a and 3b, A At the same time as increasing the number of / D conversion channels, it is possible to provide a switching circuit and a failure detection function of the A / D converter 1, thereby improving the reliability of the signal conversion result.

  In the above description, two detection objects and one A / D port have been described. However, the present invention is not limited to this, and the same applies when more objects are connected to one A / D port. An effect is obtained.

Embodiment 2. FIG.
Next, an A / D converter according to Embodiment 2 of the present invention will be described. FIG. 4 is a circuit diagram of the A / D converter according to the second embodiment. The A / D conversion device 20 according to the second embodiment shows a state in which the CPU 6 has the A / D converter 1 built therein. The CPU 6 has an A / D port (A / D # 1) 6a and normal first and second output ports (P1, P2) 6b and 6c. A first sensor 21 and a second sensor 22 similar to the first sensor 21 are connected in parallel to the A / D port 6a. The first sensor 21 and the second sensor 22 have resistance values Rt1 and Rt2 that vary according to their characteristics. For example, a thermistor having a resistance change due to a temperature change or a potentiometer whose resistance value changes due to movement.

  The first sensor 21 and the second sensor 22 are pulled up via the resistor 8 to the power supply Vcc. The first sensor 21 and the second sensor 22 are connected in series with first and second switching elements 23 and 24 each composed of a bipolar transistor or the like. The first and second switching elements 23 and 24 are connected to and controlled by the output ports 6b and 6c, respectively. The capacitor 9 is connected to the A / D port 6a for noise suppression.

  FIG. 5 is a time chart for explaining the operation of the A / D converter 20 according to the second embodiment. In FIG. 5, reference symbol A2 indicates the operating state of the second output port 6c, and reference symbol B2 indicates the operating state of the first output port 6b along the time axis t. Symbol C2 indicates the input status of the A / D port 6a.

  First, paying attention to t2 to t3, the second output port 6c = Low and the first output port 6b = high. This is because the second transistor 24 connected to the second output port 6c is turned off, and the first transistor 23 connected to the first output port 6b is controlled to be turned on. When the first transistor 23 is turned on, only the first sensor 21 is connected, and the second sensor 22 is in an open state. Therefore, a voltage division ratio between the resistance value Rt1 of the first sensor 21 and the resistance value of the pull-up resistor 8 is input to the A / D port 6a.

  Next, when attention is paid to t3 to t4, only the second sensor 22 is connected as described above, and as a result, the resistance value Rt2 of the second sensor 22 and the resistance value of the pull-up resistor 8 are connected to the A / D port 6a. The partial pressure ratio is input. By these two controls, the detection signals of the first and second sensors 21 and 22 are respectively input to the A / D port 6a, and the CPU 6 can acquire the values. The above is what the conventional apparatus has implemented.

  Next, the A / D conversion apparatus 20 according to the second embodiment uses the same circuit before or before the input of the conventional apparatus, and performs fault diagnosis by adding another simple control. is there.

  First, from t1 to t2, both the first and second output ports 6b and 6c are set to Low, both the first and second transistors 23 and 24 are turned off, and the first and second sensors 21 and 22 are not connected. In this state, only the pull-up resistor 8 is connected, so that almost the same voltage as the power source Vcc to which the other pull-up resistor 8 is connected is input to the A / D port 6a. If the device is normal, the voltage of the power supply Vcc is input. If a voltage other than the power supply Vcc is input, the pull-up resistor 8, the power supply Vcc, the A / D port 6a, the first and second transistors 23 are input. 24, one or both of the first and second output ports 6b and 6c may be defective, and the input values of the first and second sensors 21 and 22 are also determined to be true values. It will not be possible.

  Next, from t4 to t5, the first and second output ports 6b and 6c are both High, the first and second transistors 23 and 24 are both on, and the first and second sensors 21 and 22 are connected. It is said. That is, the first and second sensors 21 and 22 are connected in parallel. Therefore, if the value does not become lower than the values of the first and second sensors 21 and 22 input from t2 to t4, it can be determined that there is a failure.

  Here, at t4 to t5, the voltage response when the first and second sensors 21 and 22 are connected in parallel is the voltage when only the first sensor 21 or the second sensor 22 is individually connected. It is also possible to compare the correlation value of how many volts of the response value corresponds with a conversion means such as a look-up table to determine the validity of the detected value.

  Possible failure modes include a failure of one or both of the first and second sensors 21 and 22, a failure of the first and second transistors 23 and 24, or the first and second output ports 6b and 6c, and the like. However, in any case, the values of the first and second sensors 21 and 22 input at t2 to t4 cannot be determined to be true values.

  Conversely, if t1 to t2 and t4 to t5 are normal values, the values acquired by the first and second sensors 21 and 22 can be determined to be normal. Thus, by adding a mode different from the control content before or after each sensor is detected independently, there is an effect that a fail-safe function can be added using the same circuit.

  The time chart shown in FIG. 5 shows an example of the operation, and the switching pattern can be freely set as long as each mode can be realized sequentially. For example, a time chart as shown in FIG. 6 may be used as another switching pattern, and the signal selection and failure detection functions can be provided as in the case of the time chart of FIG.

  In the above description, two sensors and one A / D port have been described. However, the present invention is not limited to this, and the same effect can be obtained when more sensors are connected.

  In the present embodiment, bipolar transistors have been exemplified as the first and second switching elements 23 and 24. However, the present invention is not limited to this. For example, MOSFETs, analog switch ICs, mechanical relays, etc. It goes without saying that any element having a conduction / cutoff characteristic that satisfies the required accuracy of / D conversion can be used freely.

Embodiment 3 FIG.
Next, an A / D converter according to Embodiment 3 of the present invention will be described. FIG. 7 is a circuit diagram of the A / D converter according to the second embodiment. The A / D conversion device 30 according to the third embodiment is such that the first and second switching elements 23 and 24 are connected to the power supply Vcc side. In this case, the pull-up resistor 8 in FIG. Connected to. In addition, about another structure, it is the same as that of Embodiment 2, The description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The A / D conversion device 30 according to the third embodiment also operates in the same manner as the A / D conversion device 20 according to the embodiment and can obtain the same effects.

  In the above, the first to third embodiments of the present invention have been described. However, the present invention is not limited to these embodiments, and each embodiment can be freely combined within the scope of the present invention. Each embodiment can be modified or omitted as appropriate.

The first to third embodiments that embody the A / D converter according to the present invention have been described above. The A / D converter according to the present invention has the following features.
(1) An A / D converter according to the present invention connects an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of analog electrical quantities connected to the A / D converter. A switching circuit; and a control unit that controls each of the switching circuits independently, wherein the control unit outputs the analog electric quantity of the object to the A / D converter one by one independently. Generating a second mode in which two or more analog electrical quantities of the object are simultaneously output to the A / D converter, and a third mode in which all analog electrical quantities of the object are not output, Sometimes, the A / D conversion value of each object is individually acquired, and an abnormality of the apparatus is detected in the second mode and the third mode.
According to this configuration, without increasing the number of A / D converters, a large number of analog electrical signals to be captured can be sequentially converted into digital signals by the A / D converter, and an additional circuit can be provided. It is unnecessary and can easily add a fault diagnosis function.

(2) An A / D converter according to the present invention includes an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling the generation of the analog electric quantity of the object, and control means for controlling the switching timing of the switching means, the control means generating the analog electric quantity of the object one by one Generating a first mode that is independently performed, a second mode that simultaneously generates two or more analog electric quantities of the object, and a third mode that does not generate analog electric quantities from all the objects, An A / D conversion value of each object is individually acquired in the first mode, and an abnormality of the apparatus is detected in the second mode and the third mode.
According to this configuration, the mode is explicitly switched, and the value is acquired in synchronization with the A / D conversion timing in each mode. In addition, it is possible to detect an abnormality of the apparatus by confirming that the conversion value is within a predetermined range in the second mode and the third mode.

(3) An A / D converter according to the present invention includes an A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling the generation of the analog electric quantity of the object, and control means for controlling the switching timing of the switching means, wherein the control means independently grounds the objects one by one. The first mode is established, and two or more objects are grounded at the same time to form the second mode, and all the objects are not grounded to form the third mode. An A / D conversion value of an object is acquired, and an abnormality of the apparatus is detected in the second mode and the third mode.
According to this configuration, the generation of the electric quantity from the object is output to the A / D converter while being independently controlled, and the A / D of each object is performed in the first, second, and third modes. The conversion value and abnormality of the A / D converter can be detected.

(4) An A / D converter according to the present invention includes an A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling generation of analog electric quantity of the object, and control means for controlling the switching timing of the switching means, wherein the control means independently connects the objects to the power source one by one. To form a first mode, to connect two or more objects to a power source at the same time to form a second mode, to connect all the objects to a power source to form a third mode, and An A / D conversion value of each object is acquired in the first mode, and an abnormality of the apparatus is detected in the second mode and the third mode.
According to this configuration, the generation of the electric quantity from the object is output to the A / D converter while being independently controlled, and the A / D of each object is performed in the first, second, and third modes. The conversion value and abnormality of the A / D converter can be detected.

(5) Further, the A / D conversion device according to the present invention includes a means for converting a characteristic value with respect to an analog electric quantity when the object is connected in parallel in the second mode, and the second mode And detecting a characteristic value of the object.
According to this configuration, the characteristic value of the object can be detected even in the second mode.

DESCRIPTION OF SYMBOLS 1 A / D converter 2 Control part 3 Switching circuit 3a 1st switching circuit 3b 2nd switching circuit 4 1st target object 5 2nd target object 6 CPU
6a A / D port 6b 1st output port 6c 2nd output port 7a 1st series resistor 7b 2nd series resistor 8 Pull-up resistor 9 Capacitor 10, 20, 30 A / D converter 21 1st sensor 22 Second sensor 23 First switching element 24 Second switching element

In order to solve the above problems, an A / D converter according to the present invention includes an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of analogs in the A / D converter. In an A / D conversion device comprising a switching circuit for connecting an electric quantity and a control means for independently controlling the switching circuit, the control means independently converts the analog electric quantity of the object one by one. The first mode for outputting to the A / D converter, the second mode for outputting two or more analog electric quantities of the object to the A / D converter at the same time, and not outputting all the analog electric quantities of the object third and mode, is generated by switching through the switching circuit by the control unit, the a / D varying in each mode after a predetermined time after switching of said switching circuit Acquires the value performed, wherein the A / D conversion values for each object separately obtained when the first mode, the abnormality of the device based on the A / D conversion value when the second mode And detecting an abnormality of the apparatus with reference to a power supply voltage connected to the A / D converter in the third mode .

Embodiment 3 FIG.
Next, an A / D converter according to Embodiment 3 of the present invention will be described. FIG. 7 is a circuit diagram of the A / D converter according to the third embodiment. The A / D conversion device 30 according to the third embodiment is such that the first and second switching elements 23 and 24 are connected to the power supply Vcc side. In this case, the pull-up resistor 8 in FIG. Connected to. In addition, about another structure, it is the same as that of Embodiment 2, The description is abbreviate | omitted by attaching | subjecting the same code | symbol.

The A / D conversion device 30 according to the third embodiment also operates in the same manner as the A / D conversion device 20 according to the second embodiment and can obtain the same effects.

The first to third embodiments that embody the A / D converter according to the present invention have been described above. The A / D converter according to the present invention has the following features.
(1) An A / D converter according to the present invention connects an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of analog electrical quantities connected to the A / D converter. A switching circuit; and a control unit that controls each of the switching circuits independently, wherein the control unit outputs the analog electric quantity of the object to the A / D converter one by one independently. , The second mode in which two or more analog electrical quantities of the object are simultaneously output to the A / D converter, and the third mode in which all analog electrical quantities of the object are not output are switched by the control means. is generated by switching through the circuit, to acquire the value subjected to a / D conversion in each mode after a predetermined time after switching of said switching circuit, said first mode The A / D conversion values for each object separately acquired when de, detecting the abnormality of the device based on the A / D conversion value when the second mode, wherein when said third mode A / An apparatus abnormality is detected with reference to a power supply voltage connected to the D converter .
According to this configuration, without increasing the number of A / D converters, a large number of analog electrical signals to be captured can be sequentially converted into digital signals by the A / D converter, and an additional circuit can be provided. It is unnecessary and can easily add a fault diagnosis function.

(2) An A / D converter according to the present invention includes an A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling the generation of the analog electric quantity of the object, and control means for controlling the switching timing of the switching means, the control means generating the analog electric quantity of the object one by one The control means includes a first mode that is independently performed, a second mode that simultaneously generates two or more analog electric quantities of the object, and a third mode that does not generate analog electric quantities from all the objects. Is generated by switching through the switching circuit, and after a predetermined time after switching the switching circuit, A / D conversion is performed in each mode to obtain the value. As well as, the A / D conversion value of the object acquired separately, the detected abnormality of the apparatus on the basis of the A / D conversion value when the second mode when the first mode, the third An abnormality of the apparatus is detected by referring to a power supply voltage connected to the A / D converter in the mode .
According to this configuration, the mode is explicitly switched, and the value is acquired in synchronization with the A / D conversion timing in each mode. In addition, it is possible to detect an abnormality of the apparatus by confirming that the conversion value is within a predetermined range in the second mode and the third mode.

(3) An A / D converter according to the present invention includes an A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling the generation of the analog electric quantity of the object, and control means for controlling the switching timing of the switching means, wherein the control means independently grounds the objects one by one. The first mode is established, the second mode is established by simultaneously grounding two or more of the objects, the third mode is established by not grounding all the objects, and each mode is controlled by the control means. Generated by switching through the switching circuit, and acquires the value by performing A / D conversion in each mode after a predetermined time after switching of the switching circuit Rutotomoni, wherein said A / D conversion values for each object separately obtained when the first mode, detecting the abnormality of the device based on the A / D conversion value when the second mode, the third An abnormality of the apparatus is detected by referring to a power supply voltage connected to the A / D converter in the mode .
According to this configuration, the generation of the electric quantity from the object is output to the A / D converter while being independently controlled, and the A / D of each object is performed in the first, second, and third modes. The conversion value and abnormality of the A / D converter can be detected.

(4) An A / D converter according to the present invention includes an A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a plurality of objects connected to the A / D converter. Switching means for independently controlling generation of analog electric quantity of the object, and control means for controlling the switching timing of the switching means, wherein the control means independently connects the objects to the power source one by one. form a first mode by, form a second mode by connecting the object two or more simultaneously to power, form a third mode by all of the object is not connected to power supply, the respective A mode is generated by switching through the switching circuit by the control means, and A / D conversion is performed in each mode after a predetermined time after switching of the switching circuit. Performed to acquire the value, the acquired A / D conversion value of each object, the abnormality was detected in the device based on the A / D conversion value when the second mode when the first mode, An abnormality of the apparatus is detected with reference to a power supply voltage connected to the A / D converter in the third mode .
According to this configuration, the generation of the electric quantity from the object is output to the A / D converter while being independently controlled, and the A / D of each object is performed in the first, second, and third modes. The conversion value and abnormality of the A / D converter can be detected.

Claims (5)

An A / D converter that converts an analog electrical quantity of an object to be detected into a digital quantity, a switching circuit that connects a plurality of analog electrical quantities to the A / D converter, and the switching circuit are independently controlled. In an A / D conversion device comprising a control means,
The control means includes a first mode in which analog electric quantities of the object are independently output to the A / D converter one by one, and two or more analog electric quantities of the object are simultaneously applied to the A / D converter. Generating a second mode for outputting to the third mode, and a third mode for not outputting all the analog electric quantity of the object, and individually acquiring an A / D conversion value of each object in the first mode, An A / D conversion apparatus that detects an abnormality of the apparatus in the second mode and the third mode. An A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a switching unit that independently controls generation of analog electric quantities of a plurality of objects connected to the A / D converter. And an A / D conversion device comprising control means for controlling the switching timing of the switching means,
The control means includes a first mode in which the analog electric quantity of the object is independently generated one by one, a second mode in which two or more analog electric quantities of the object are simultaneously generated, and all the objects A third mode in which no analog electricity is generated from an object, and A / D conversion values of the respective objects are individually acquired in the first mode, and in the second mode and the third mode. An A / D conversion device characterized by detecting an abnormality of the device. An A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a switching unit that independently controls generation of analog electric quantities of a plurality of objects connected to the A / D converter. And an A / D conversion device comprising control means for controlling the switching timing of the switching means,
The control means sets the first mode by grounding the objects independently one by one, and sets the second mode by grounding two or more objects at the same time, and grounds all the objects. The third mode, the A / D conversion value of each object is acquired in the first mode, and the abnormality of the apparatus is detected in the second mode and the third mode. A / D conversion device. An A / D converter that converts an analog electric quantity of an object to be detected into a digital quantity, and a switching unit that independently controls generation of analog electric quantities of a plurality of objects connected to the A / D converter. And an A / D conversion device comprising control means for controlling the switching timing of the switching means,
The control means forms the first mode by independently connecting the objects to the power source one by one, and forms the second mode by simultaneously connecting two or more objects to the power source. The third mode is established by not connecting all objects to the power source, the A / D conversion values of the respective objects are acquired in the first mode, and the apparatus malfunctions in the second mode and the third mode. A / D conversion device characterized by detecting   In the second mode, there is provided means for converting a characteristic value with respect to an analog electric quantity when the object is connected in parallel, and the characteristic value of the object is detected in the second mode. The A / D conversion device according to claim 3 or 4.

Images