Analog quantity acquisition module, analog quantity acquisition device and rapid prototyping equipment

Abstract

The utility model provides an analog quantity acquisition module and device and rapid prototyping equipment, and belongs to the technical field of data acquisition and measurement, and the analog quantity acquisition module comprises a voltage dividing resistor, a gear resistor, a buffer and a voltage reference circuit. The first end of the voltage dividing resistor is connected with a power supply, and the other end is connected with the first end of the gear resistor. The voltage reference circuit is connected between the buffer and the first end of the gear resistor, so that a preset voltage difference is kept between the output end of the buffer and the first end of the gear resistor; the first input end of the buffer is connected with the second end of the gear resistor. When the to-be-measured resistor is connected between the first end of the gear resistor and the ground, the current of the to-be-measured resistor is made to be constant through the voltage reference circuit, finally the buffer outputs the measurement result used for calculating the resistance value of the to-be-measured resistor, a constant current source does not need to be additionally arranged, and the cost is reduced while the measurement precision is guaranteed.

Description

Technical Field

[0001] The present application relates to the field of data acquisition and measurement technology, and in particular to an analog quantity acquisition module, device and rapid prototyping equipment. Background Art

[0002] Rapid Control Prototype (RCP) is a verification device used in the control system development process. It is mainly used to quickly deploy algorithms to hardware in the early stages of product development or algorithm research, so as to test the developed products in a real environment. For example, rapid prototyping equipment can be used in the automotive electronics field to build a development and verification platform for complex control system development. When the rapid prototyping equipment is working, it is necessary to first connect to the real object to be tested, then give a control signal to the real object to be tested, and receive a feedback signal from the real object to be tested, so as to obtain a new control signal or verification result based on the feedback signal. Therefore, rapid prototyping equipment is usually required to have analog quantity acquisition functions, including resistance value measurement and voltage measurement.

[0003] At present, in order to improve measurement accuracy, for example, in analog quantity acquisition scenarios for resistor value measurement, the current method is usually used. This method mostly requires the use of high-cost constant current source equipment, which leads to a high overall measurement cost. Utility Model Content

[0004] In view of the above problems, the present application provides an analog quantity acquisition module, device and rapid prototyping equipment.

[0005] In a first aspect, the present application provides an analog quantity acquisition module, comprising a resistance measurement unit; the resistance measurement unit comprises a voltage divider resistor, a gear resistor, a buffer, and a voltage reference circuit;

[0006] The first end of the voltage dividing resistor is connected to the power supply, and the second end is connected to the first end of the gear resistor;

[0007] The voltage reference circuit is connected between the output end of the buffer and the first end of the gear resistor, so that a preset voltage difference is maintained between the output end of the buffer and the first end of the gear resistor;

[0008] The first input end of the buffer is connected to the second end of the gear resistor, and the second input end is connected to the output end of the buffer;

[0009] Wherein, when the resistor to be measured is connected between the second end of the gear resistor and the ground, the output end of the buffer outputs a measurement result for calculating the resistance value of the resistor to be measured.

[0010] Optionally, the resistance measurement unit includes a plurality of the gear resistors, and the resistance measurement unit also includes a controller and a switching unit;

[0011] The switching unit includes a control end, a common end and a plurality of contact ends, the control end is connected to the controller to receive a gear shift instruction output by the controller, the common end is connected to the second end of the voltage-dividing resistor, and each of the contact ends is correspondingly connected to a first end of the gear resistor; the switching unit controls the common end to be turned on to one of the plurality of contact ends according to the gear shift instruction.

[0012] Optionally, the resistance measurement unit includes a plurality of the gear resistors, and the resistance measurement unit also includes a controller and a switching unit;

[0013] The switching unit includes a control end, a common end and a plurality of contact ends, the control end is connected to the controller to receive a gear shift instruction output by the controller, the common end is connected to one end of the resistor to be measured, and each of the contact ends is correspondingly connected to the second end of a gear resistor; the switching unit controls the common end to be turned on to one of the plurality of contact ends according to the gear shift instruction.

[0014] Optionally, the switching unit includes a multi-contact relay or a single-pole multi-throw switch.

[0015] Optionally, the resistance values ​​of the multiple gear resistors are different.

[0016] Optionally, the resistance measurement unit is connected to a processor module and outputs the measurement result to the processor module, so that the processor module obtains the resistance of the resistor to be measured based on the measurement result, the preset voltage difference and the resistance of the gear resistor.

[0017] Optionally, it further includes a sensor data measurement unit; the sensor data measurement unit includes a reference voltage source, a voltage stabilization circuit and at least one measurement circuit;

[0018] The reference voltage source is connected to the input terminal of the voltage stabilizing circuit to provide a reference voltage level to the voltage stabilizing circuit;

[0019] The output end of the voltage stabilizing circuit is used to be connected to the power supply end of at least one sensor to be tested, so as to supply power to at least one sensor to be tested according to the reference level;

[0020] The input end of the measuring circuit is used to be connected to the output end of the sensor to be tested to receive the sensing signal output by the sensor to be tested, and the output end of the measuring circuit is used to output a sensing measurement result representing the size of the sensing signal.

[0021] Optionally, the measurement circuit further includes a reference terminal, wherein the reference terminal is connected to the reference voltage source to receive the reference level.

[0022] In a second aspect, in one embodiment, the present application provides an analog quantity acquisition device, comprising an analog quantity acquisition module as described above.

[0023] In a third aspect, in one embodiment, the present application provides a rapid prototyping device, including an analog quantity acquisition device as described above, wherein the analog quantity acquisition device is connected to an object to be measured to collect analog quantity data from the object to be measured.

[0024] In summary, the embodiment of the present application utilizes a voltage-dividing resistor, a gear resistor and a resistor to be measured to be connected in series to form a voltage-dividing network, so that the current provided by the power supply flows sequentially between the voltage-dividing resistor, the gear resistor and the resistor to be measured. The voltage reference circuit is used to maintain a preset voltage difference between the output end of the buffer and the first end of the gear resistor. Since the first input end and the output end of the buffer are equipotential points, the voltage difference between the two ends of the gear resistor is always equal to the preset voltage difference, so that the current flowing through the voltage-dividing resistor, the gear resistor and the resistor to be measured is constant. Furthermore, by introducing a buffer, the voltage at one end of the resistor to be measured can be stably fed back to its input end, thereby ensuring that the voltage at both ends of the resistor to be measured can be accurately output, improving the accuracy of the measurement, and through the series connection mode of the voltage-dividing resistor, the gear resistor and the resistor to be measured, combined with the application of the voltage reference circuit and the buffer, the accurate measurement of the resistance value of the resistor to be measured is achieved, and the current flowing through the resistor to be measured during the measurement process is also guaranteed to be constant, without the need to set up an additional constant current source, while ensuring the measurement accuracy and reducing the measurement cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of a resistance value acquisition circuit in the related art in one embodiment of the present application.

[0027] Figure 2 This is a circuit structure diagram of a resistance measurement unit in an analog quantity acquisition module in an embodiment of the present application.

[0028] Figure 3 This is a circuit structure diagram of a resistance measurement unit in an analog quantity acquisition module in another embodiment of the present application.

[0029] Figure 4 This is a circuit structure diagram of a resistance measurement unit in an analog quantity acquisition module in another embodiment of the present application.

[0030] Figure 5 This is a circuit structure diagram of a sensor data measurement unit in an analog quantity acquisition module in an embodiment of the present application.

[0031] Figure 6 This is a schematic diagram of an analog quantity acquisition device in one embodiment of the present application.

[0032] Figure 7 This is a schematic diagram of an application scenario of a rapid prototyping device in one embodiment of the present application.

[0033] Explanation of the reference numerals: 1. resistance measurement unit; 11. voltage reference circuit; 12. controller; 13. switching unit; 2. sensor data measurement unit; 21. reference voltage source; 22. voltage stabilizing circuit; 23. measurement circuit. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0035] In the description of the present application, it should be understood that the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. In the present application, the word "exemplary" is used to mean "used as an example, illustration or description". Any embodiment described as "exemplary" in the present application is not necessarily interpreted as being more preferred or more advantageous than other embodiments. In order to enable any technician in the field to implement and use the present application, the following description is given. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present application can also be implemented without using these specific details. In other examples, well-known structures and processes will not be elaborated in detail to avoid unnecessary details that make the description of the present application obscure. Therefore, the present application is not intended to be limited to the embodiments shown, but is consistent with the widest range of principles and features disclosed in the present application.

[0036] Based on the problems mentioned in the above background technology, Figure 1 As shown, it is a schematic diagram of a resistance measurement using the current method in an existing analog quantity acquisition scenario, wherein a constant current source is used to connect the resistor to be measured, and then by measuring the voltage value across the resistor to be measured, the resistance value of the resistor to be measured can be calculated based on the voltage value and the output of the constant current source. Among them, a digital-to-analog converter (DAC) can be selected as a constant current source. If multi-channel resistance measurement is required, a constant current source needs to be equipped in each channel. Although this measurement method can guarantee a high measurement accuracy, due to the high cost of the constant current source, the overall measurement cost will be high. How to balance the measurement cost and measurement accuracy has been a topic of research in this field.

[0037] Based on the above problems, on the one hand, Figure 2 As shown, in one embodiment, the present application provides an analog quantity acquisition module, which includes a resistance measurement unit 1 for measuring the resistance of a resistor to be measured. The resistance measurement unit 1 includes a voltage divider resistor R0, a gear resistor R1, a buffer U1 and a voltage reference circuit 11.

[0038] The first end of the voltage-dividing resistor R0 is connected to the power source V1, and the second end is connected to the first end of the gear resistor R1. The voltage reference circuit 11 is connected to the output end of the buffer U1 and the first end of the gear resistor R1, so that a preset voltage difference is maintained between the output end of the buffer U1 and the first end of the gear resistor R1. The first input end of the buffer U1 is connected to the second end of the gear resistor R1, and the second input end is connected to the output end of the buffer U1.

[0039] The power supply V1 is a measurement power supply integrated in the analog quantity acquisition module, and is used to provide a current flowing through the resistor Rx to be measured. The voltage reference circuit 11 can be a voltage reference circuit based on a voltage reference chip, and the model of the voltage reference chip can be selected according to actual conditions to provide different preset voltage differences and ensure different voltage accuracies.

[0040] Among them, the buffer U1 isolates its input and output to ensure stable transmission of the signal, and when the level of the first input terminal is not higher than the power supply voltage of the buffer U1, the voltage amplitude of the first input terminal and the output terminal of the buffer U1 remain consistent; for example, the buffer U1 can be an operational amplifier with a gain of 1, the first input terminal can be a non-inverting input terminal, and the second input terminal can be an inverting input terminal.

[0041] When the resistor to be measured Rx is connected between the second end of the gear resistor R1 and the ground, the output end of the buffer U1 outputs a measurement result for calculating the resistance value of the resistor to be measured Rx.

[0042] Combination Figure 2As an example, the second end of the voltage-dividing resistor R0, one end of the voltage reference circuit 11 and the first end of the gear resistor R1 are connected to the first node N1; the second end of the gear resistor R1, the first input end of the buffer U1 and one end of the resistor to be measured Rx are connected to the second node N2. It should be understood that when the resistor to be measured Rx is connected between the second node N2 and the ground, since the voltage amplitude of the first input end of the buffer U1 and its output end is consistent, and the first input end of the buffer U1 is connected to the second node N2, the second node N2 and the output end of the buffer U1 are equipotential points. And the voltage reference circuit 11 is used to maintain a preset voltage difference between the output end of the buffer U1 and the first node N1, so the potential difference between the first node N1 and the second node N2 is the preset voltage difference, and the first node N1 and the second node N2 are respectively connected to the two ends of the gear resistor R1, so that the voltage across the two ends of the gear resistor R1 is the preset voltage difference. Therefore, the current flowing through the gear resistor R1 can be expressed as: I = V0 / R; where R is the resistance of the gear resistor R1, and V0 is the preset voltage difference. Since the gear resistor R1, the voltage-dividing resistor R0, and the resistor to be measured Rx are connected in series, the current flowing through the voltage-dividing resistor R0 and the resistor to be measured Rx is equal to the current flowing through the gear resistor R1, that is, when the preset voltage difference and the resistance of the gear resistor R1 remain unchanged, the current flowing through the resistor to be measured Rx remains unchanged, so that the current flowing through the resistor to be measured Rx is constant.

[0043] In the above embodiment, the voltage-dividing resistor R0, the gear resistor R1 and the resistor to be measured Rx are connected in series to form a voltage-dividing network, so that the current provided by the power supply V1 flows sequentially between the voltage-dividing resistor R0, the gear resistor R1 and the resistor to be measured Rx. The voltage reference circuit 11 is used to maintain a preset voltage difference between the output end of the buffer U1 and the first node N1. Since the first input end and the output end of the buffer U1 are equipotential points, the voltage difference across the gear resistor R1 is always the preset voltage difference, so that the current flowing through the voltage-dividing resistor R0, the gear resistor R1 and the resistor to be measured Rx is constant. Furthermore, since the resistor Rx to be measured is connected between the second end of the gear resistor R1 and the ground, the voltage value of the first input terminal of the buffer U1 is equal to the voltage drop generated by the resistor Rx to be measured. By introducing the buffer U1, the voltage of the second node N2 can be stably fed back to its output terminal, so that the output terminal voltage of the buffer U1 is equal to the voltage drop generated by the resistor Rx to be measured, thereby ensuring that the voltage across the resistor Rx to be measured can be accurately output, thereby improving the measurement accuracy. In addition, through the series connection of the voltage divider resistor R0, the gear resistor R1 and the resistor Rx to be measured, combined with the application of the voltage reference circuit 11 and the buffer U1, the accurate measurement of the resistance value of the resistor Rx to be measured is achieved, while ensuring that the current flowing through the resistor Rx to be measured during the measurement process is constant, without the need to additionally set up a constant current source, thereby reducing costs while ensuring high measurement accuracy.

[0044] It should be noted that the gear resistor R1 can be a fixed value resistor or a resistor with controllable resistance, so as to meet different measurement requirements.

[0045] Reference Figure 3 As another implementation of the resistance measuring unit 1, the resistance measuring unit 1 may include a plurality of gear resistors R1. Based on this, the resistance measuring unit 1 may also include a controller 12 and a switching unit 13, and the controller 12 and the switching unit 13 are connected between the voltage dividing resistor R0 and the gear resistor R1.

[0046] Specifically, the switching unit 13 includes a control end, a common end and multiple contact ends. The control end is connected to the controller 12 to receive the gear shifting instruction output by the controller 12, the common end is connected to the second end of the voltage-dividing resistor R0, and each contact end is correspondingly connected to the first end of a gear resistor R1; the switching unit 13 controls the common end to be turned on to one of the multiple contact ends according to the gear shifting instruction.

[0047] The switching unit 13 includes a multi-contact relay or a single-pole multi-throw switch. The resistance values ​​of the multiple gear resistors R1 are different from each other. The number of gear resistors R1 can be consistent with the number of contact ends of the switching unit 13, and each gear resistor R1 corresponds to a contact in the switching unit 13.

[0048] Combination Figure 3 , Figure 3 The example shows a circuit structure diagram in which there are two gear resistors R1, the switching unit 13 adopts a multi-contact relay K, and the controller 12 and the switching unit 13 are connected between the voltage-dividing resistor R0 and the gear resistor R1. The power supply V2 is connected to the power supply terminal vd of the multi-contact relay K. The contact terminals of the multi-contact relay K can be set to two, namely, port a1 and port a2. The first end of each gear resistor R1 is correspondingly connected to a contact terminal. The control terminal con of the multi-contact relay K is connected to the controller 12 to receive the gear shifting instruction output by the controller 12, so that the multi-contact relay K controls the common terminal com to be turned on to one of the multiple contact terminals according to the gear shifting instruction, so that the voltage-dividing resistor R0 can be selected to be turned on to one of the two gear resistors R1.

[0049] Reference Figure 4 As another embodiment of the resistance measuring unit 1, the resistance measuring unit 1 may include a plurality of gear resistors R1. Based on this, the resistance measuring unit 1 may also include a controller 12 and a switching unit 13, and the controller 12 and the switching unit 13 are connected between the gear resistors R1 and the resistor to be measured Rx.

[0050] Specifically, the switching unit 13 includes a control end, a common end and multiple contact ends. The control end is connected to the controller 12 to receive the shift command output by the controller 12, the common end is connected to one end of the resistor to be measured Rx, and each contact end is correspondingly connected to the second end of a gear resistor R1; the switching unit 13 controls the common end to be turned on to one of the multiple contact ends according to the shift command.

[0051] Combination Figure 4 , Figure 4 The circuit structure diagram in which there are two gear resistors R1, the switching unit 13 adopts a multi-contact relay K, and the controller 12 and the switching unit 13 are connected between the gear resistor R1 and the resistor to be measured Rx is exemplified. The power supply V2 is connected to the power supply terminal vd of the multi-contact relay K. The contact terminal of the multi-contact relay K can be set to two, namely, port a1 and port a2. The second end of each gear resistor R1 is connected to a corresponding contact terminal. The control terminal con of the multi-contact relay K is connected to the controller 12 to receive the gear shifting instruction output by the controller 12, so that the multi-contact relay K controls the common terminal com to be turned on to one of the multiple contact terminals according to the gear shifting instruction, so that the resistor to be measured Rx can be selected to be turned on to one of the two gear resistors R1.

[0052] It should be understood that, when the preset voltage difference formed by the voltage reference circuit 11 remains unchanged, the voltage applied to both ends of the gear resistor R1 is always the preset voltage difference, and the larger the resistance value of the gear resistor R1, the smaller the current flowing through the gear resistor R1, and the smaller the current flowing through the resistor to be measured Rx. Similarly, the smaller the resistance value of the gear resistor R1, the larger the current flowing through the gear resistor R1, and the larger the current flowing through the resistor to be measured Rx. Since the maximum output voltage at the output end of the buffer U1 is limited by the buffer supply voltage, when the resistor to be measured Rx is large, a gear resistor R1 with a larger resistance value should be selected so that the current flowing through the resistor to be measured Rx is reduced to ensure that the voltage generated on the resistor to be measured Rx is not too high, thereby avoiding the situation of exceeding the range due to saturation of the subsequent operational amplifier. On the contrary, when the resistance to be measured Rx is small, a smaller gear resistor R1 should be selected to increase the current flowing through the resistance to be measured Rx, thereby generating enough voltage on the resistance to be measured Rx for more accurate measurement.

[0053] In the above embodiment, the common terminal is controlled to be turned on to one of the multiple contact terminals by the switching unit 13 according to the shift command, so that the gear resistor R1 with different resistance values ​​is connected between the voltage divider resistor R0 and the resistor to be measured Rx to change the total resistance of the voltage divider network, thereby changing the current flowing through the resistor to be measured Rx, so that the gear resistor R1 with different resistance values ​​can be selected according to the different resistors to be measured Rx, thereby realizing multi-range measurement of the resistance value of the resistor to be measured Rx, and improving the accuracy of the resistance value measurement of the resistor to be measured Rx.

[0054] As another implementation of the resistance measuring unit 1, the voltage reference circuit 11 can be a voltage reference circuit with fixed parameters, and the size of the preset voltage difference maintained between the output end of the buffer U1 and the first end of the gear resistor R1 is a constant value. The voltage reference circuit 11 can also be a voltage reference circuit with controllable parameters, and the size of the preset voltage difference maintained between the output end of the buffer U1 and the first end of the gear resistor R1 can be adjusted to meet different measurement requirements.

[0055] As a further implementation of the resistance measuring unit 1, the resistance measuring unit 1 can also be connected to a processor module to output the measurement result to the processor module, so that the processor module obtains the resistance of the resistor to be measured Rx based on the measurement result, the preset voltage difference and the resistance of the gear resistor R1.

[0056] The processor module may be a processor module in a host computer responsible for receiving and processing data collected by the analog quantity acquisition module, or may be a processor or analog-to-digital conversion chip in the analog quantity acquisition module.

[0057] In one example, the resistance value of the resistor to be measured Rx can be expressed as: R'=Vx1 / I; wherein Vx1 is the measurement result, that is, the measurement result output by the output end of the buffer U1; I is the current flowing through the gear resistor R1, and the current flowing through the gear resistor R1 can be obtained according to the preset voltage difference and the resistance value of the gear resistor R1.

[0058] It should be noted that there can be multiple resistance measuring units 1 to achieve multi-channel resistance measurement. The channels are independent of each other, and the preset voltage difference and the resistance of the gear resistor R1 in each resistance measuring unit 1 can be set separately, so that the measuring range between each measurement channel can be the same or different, so as to make a more flexible configuration according to actual needs.

[0059] Reference Figure 5 As a further implementation of the analog quantity acquisition module, the analog quantity acquisition module further includes a sensor data measurement unit 2. The sensor data measurement unit 2 includes a reference voltage source 21, a voltage stabilizing circuit 22 and at least one measurement circuit 23.

[0060] The reference voltage source 21 is connected to the input end of the voltage stabilizing circuit 22 to provide a reference level to the voltage stabilizing circuit 22. The output end of the voltage stabilizing circuit 22 is used to connect to the power supply end of the sensor to be tested to supply power to at least one sensor to be tested according to the reference level. The input end of the measuring circuit 23 is connected to the output end of the sensor to be tested to receive the sensor signal output by the sensor to be tested, and the output end of the measuring circuit is used to output the sensor measurement result representing the size of the sensor signal.

[0061] It should be understood that the voltage stabilizing circuit 22 can be connected to the power supply end of one or more sensors to be tested, and supply power to one or more sensors to be tested at the same time. Each measuring circuit 23 is connected to the output end of a sensor to be tested to measure the sensor signal of the sensor to be tested. It should also be understood that the sensor to be tested connected to the measuring circuit 23 can be powered by the voltage stabilizing circuit 22 or by an external power supply. Among them, the sensor to be tested can be a pressure sensor, a temperature sensor, etc.

[0062] In the above implementation, a reference voltage source 21 and a voltage stabilizing circuit 22 are integrated in the analog quantity acquisition module. The voltage stabilizing circuit 22 supplies power to the sensor to be tested based on the reference level, thereby avoiding unstable measurement results of the sensor to be tested due to fluctuations in the external power supply, and ensuring that the measurement value of the sensor to be tested is as close to the true value as possible.

[0063] Wherein, as an implementation of the voltage stabilizing circuit 22, the voltage stabilizing circuit 22 may include a linear regulator, which is connected to a power supply (not shown in the figure) and a reference voltage source 21, and outputs the reference level provided by the reference voltage source 21 after amplifying a certain multiple, and supplies power to the sensor to be tested, and the maximum output voltage of the reference voltage source 21 does not exceed the level of the power supply. It should be understood that when the sensor to be tested is installed in an external system and powered by the external system, due to the large number of components and large volume of the external system, electrical fluctuations are easily generated, which may cause the sensor signal output by the sensor to be tested to be a superposition of the true value and the electrical fluctuations. In contrast, the possibility of fluctuations generated by the high internal stability of the analog quantity acquisition module is relatively small, and even if fluctuations occur, the fluctuations are relatively small. Therefore, in the present embodiment, the electrical fluctuations of the sensor to be tested are reduced by the analog quantity acquisition module to power the sensor to be tested, so that the value output by the sensor to be tested is closer to the true value, and the measurement accuracy is improved.

[0064] Furthermore, the linear regulator can also be set as a linear regulator with a tracking function, so that the linear regulator can automatically adjust its output voltage according to the reference level and the target voltage set internally, so that the linear regulator can track the change of the reference level in real time and adjust its output voltage accordingly. Figure 5 , Figure 5 The signal REF in represents the reference level, and Vcc represents the output voltage of the linear regulator. In this embodiment, the output voltage can be adjusted by adjusting the gain of the linear regulator, for example, the output voltage can be 5V or 8V. In other embodiments, the output voltage can also be configured according to the actual power supply requirements of the sensor to be tested.

[0065] As a further embodiment of the measuring circuit 23, the measuring circuit 23 further includes a reference terminal, which is connected to the reference voltage source 21 to receive a reference voltage level. The measuring circuit 23 includes an operational amplifier U2 and an analog-to-digital converter chip (Analog-to-Digital Converter ， The first input terminal of the operational amplifier U2 (such as the in-phase input terminal) is connected to the output terminal of the sensor to be tested, and the output terminal of the operational amplifier U2 is connected to the second input terminal of the operational amplifier U2 (such as the inverting input terminal) and the input terminal of the analog-to-digital conversion chip U3, which is used to buffer or amplify the sensing signal to obtain the signal to be tested; the analog-to-digital conversion chip U3 includes a reference terminal, and an external reference voltage is required for the analog-to-digital conversion chip U3 to perform data conversion. In this embodiment, the reference terminal of the analog-to-digital conversion chip U3 is connected to the reference voltage source 21 to convert the signal to be tested according to the reference level to obtain the sensing measurement result.

[0066] In the above implementation, the analog-to-digital conversion chip U3 in the measurement circuit 23 outputs the sensor measurement result based on the reference level, and the reference levels of the measurement circuit 23 and the voltage stabilization circuit 22 are provided by the same reference voltage source 21, which reduces the cost and space occupation. Figure 5 , Figure 5 The middle signal Vt represents the sensing signal returned by the sensor to be tested, and the signal Vx2 represents the sensing measurement result output by the measurement circuit 23 that represents the size of the sensing signal.

[0067] As a further implementation of the sensor data measurement unit 2, the sensor data measurement unit 2 may also be connected to a processor module to output the sensor measurement result to the processor module, so that the processor module obtains the sensor signal size of the sensor to be measured based on the sensor measurement result.

[0068] Among them, the processor module can be a processor module in the host computer responsible for receiving and processing the data collected by the analog quantity acquisition module, or it can be a processor module in the analog quantity acquisition module. The measurement circuit 23 of the sensor data measurement unit 2 converts the analog quantity output by the sensor into a digital quantity and inputs it into the processor module, so that the processor module can obtain the sensor signal size of the sensor to be tested.

[0069] The resistance value measurement unit 1 and the sensor data measurement unit 2 in the analog quantity acquisition module can be connected to the same processor module or to different processor modules. The processor module can also be connected to a display module to display the resistance value and / or the sensor signal size.

[0070] It should be noted that the analog quantity acquisition module may include multiple sensor data measurement units 2 to achieve multi-channel sensor data measurement, and the channels are independent of each other. The output voltage of the voltage stabilizing circuit 22 and the number of measurement circuits 23 in each sensor data measurement unit 2 can be configured separately. It can be understood that the sensor data measurement unit 2 and the resistance measurement unit 1 are independent units in the analog quantity acquisition module, and the analog quantity acquisition module may include multiple resistance measurement units 1 and multiple sensor data measurement units 2, and the number of resistance measurement units 1 and the number of sensor data measurement units 2 can be set separately as needed.

[0071] In a second aspect, in one embodiment, the present application also provides an analog quantity acquisition device, referring to Figure 6 The analog quantity acquisition device includes at least one analog quantity acquisition module as described above.

[0072] It should be noted that the number of resistance measurement units 1 and the data of sensor data measurement units 2 in each analog quantity acquisition module can be set according to actual conditions, and no specific limitation is made here. In addition, in addition to the above-mentioned analog quantity acquisition module, the analog quantity acquisition device can also include a current acquisition module and other functional modules for realizing analog quantity acquisition. The analog quantity acquisition device can be in the form of a chip, a circuit board card, an independent device, etc.

[0073] In one example, the implementation principle of the present application is illustrated by taking the application of an analog quantity acquisition device in automobile data acquisition as an example.

[0074] The data acquisition system includes a host computer and multiple data acquisition devices. The types of data acquisition devices include analog quantity acquisition devices, video data acquisition devices, bus data acquisition devices, Ethernet data acquisition devices, etc., wherein the analog quantity acquisition device is connected to the object to be measured, such as the resistor to be measured Rx and the sensor to be measured. The analog quantity acquisition device collects analog quantity data of the object to be measured and sends it to the host computer, which displays, stores, analyzes and performs other operations on the collected analog quantity.

[0075] In one example, the implementation principle of the present application is explained by taking the application of an analog quantity acquisition device in automobile testing as an example.

[0076] The hardware-in-the-loop test system includes a host computer and multiple I / O boards. The types of I / O boards are, for example, AD PWM-IN boards, DAC boards, FIU boards, PWM-OUT boards, RELAY-IO boards, RC boards, PSI5&DSI3&SENT boards, multi-bus boards (Flexray / CANFD / LIN), Eth (vehicle-mounted Ethernet) boards, etc.; I / O can also be the following special boards: current output boards, thermocouple boards, battery simulators, temperature simulators, motor boards, IO_HUB boards, and the analog quantity acquisition device serves as an analog quantity acquisition board. The host computer is connected to multiple I / O boards, and multiple I / O boards are connected to the device under test. The device under test is, for example, an electronic controller (ECU, Electronic Control Unit) and peripheral devices. The host computer and multiple I / O boards are used to simulate the control object of the device under test so as to test the device under test. At this time, the analog quantity acquisition device can collect the analog quantity generated by the device under test and send it to the host computer so that the host computer can perform testing.

[0077] In a third aspect, in one embodiment, the present application further provides a rapid prototyping device, the rapid prototyping device comprising at least one analog quantity acquisition device as described above, the analog quantity acquisition device being connected to an object to be measured to collect analog quantity data from the object to be measured.

[0078] The object to be tested may include a resistor to be tested Rx and a sensor to be tested.

[0079] In one example, referring to Figure 7 As shown, the implementation principle of the present application is exemplarily explained by taking the application of rapid prototyping equipment in a vehicle system as an example.

[0080] First, before the rapid prototyping device is used, it is necessary to develop a control model in the host computer, including defining the control algorithm, communication protocol, input and output signals, etc., and issuing the control model and configuring the rapid prototyping device so that the rapid prototyping device can output signals according to the predetermined control logic. The control model in the rapid prototyping device is, for example, the control model of the electronic controller. The rapid prototyping device is connected to the object to be tested, which may include sensors and actuators such as motors and switches. The rapid prototyping device simulates the control end and controls and collects data on the real object to be tested. The rapid prototyping device sends control instructions to the object to be tested (such as an actuator) through signal output, so that it performs corresponding actions. The rapid prototyping device collects the output signal of the object to be tested, for example, the output signal of various sensors or actuators, which reflects the operating state of the object to be tested or the action to be performed. Among them, the analog quantity acquisition device can be used to collect resistance and voltage type sensor signals, and is connected to the resistor Rx to be tested and / or the sensor to be tested in the object to be tested. In addition, CAN (Controller Area Network) and LIN (Local Interconnect Network) are commonly used communication protocols in vehicle systems. Rapid prototyping equipment can communicate with the object to be tested through CAN and LIN interfaces to achieve data transmission and command execution. In addition, rapid prototyping equipment can also include H-bridge circuits, etc.

[0081] The above are only preferred embodiments of the present application, and are not intended to limit the present application in any form. Although the present application has been disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technical personnel in the field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present application. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. An analog quantity acquisition module, characterized in that: The device comprises a resistance measuring unit; the resistance measuring unit comprises a voltage dividing resistor, a gear resistor, a buffer and a voltage reference circuit; The first end of the voltage dividing resistor is connected to the power supply, and the second end is connected to the first end of the gear resistor; The voltage reference circuit is connected between the output end of the buffer and the first end of the gear resistor, so that a preset voltage difference is maintained between the output end of the buffer and the first end of the gear resistor; The first input end of the buffer is connected to the second end of the gear resistor, and the second input end is connected to the output end of the buffer; Wherein, when the resistor to be measured is connected between the second end of the gear resistor and the ground, the output end of the buffer outputs a measurement result for calculating the resistance value of the resistor to be measured.

2. The analog quantity acquisition module according to claim 1, characterized in that: The resistance measurement unit includes a plurality of the gear resistors, and the resistance measurement unit also includes a controller and a switching unit; The switching unit includes a control end, a common end and a plurality of contact ends, the control end is connected to the controller to receive a gear shift instruction output by the controller, the common end is connected to the second end of the voltage-dividing resistor, and each of the contact ends is correspondingly connected to a first end of the gear resistor; the switching unit controls the common end to be turned on to one of the plurality of contact ends according to the gear shift instruction.

3. The analog quantity acquisition module according to claim 1, characterized in that: The resistance measurement unit includes a plurality of the gear resistors, and the resistance measurement unit also includes a controller and a switching unit; The switching unit includes a control end, a common end and a plurality of contact ends, the control end is connected to the controller to receive a gear shift instruction output by the controller, the common end is connected to one end of the resistor to be measured, and each of the contact ends is correspondingly connected to the second end of a gear resistor; the switching unit controls the common end to be turned on to one of the plurality of contact ends according to the gear shift instruction.

4. The analog quantity acquisition module according to claim 2 or 3, characterized in that: The switching unit includes a multi-contact relay or a single-pole multi-throw switch.

5. The analog quantity acquisition module according to claim 2 or 3, characterized in that: The resistance values ​​of the plurality of gear resistors are different from each other.

6. The analog quantity acquisition module according to any one of claims 1 to 3, characterized in that: The resistance measurement unit is connected to the processor module and outputs the measurement result to the processor module, so that the processor module obtains the resistance value of the resistor to be measured based on the measurement result, the preset voltage difference and the resistance value of the gear resistor.

7. The analog quantity acquisition module according to claim 1, characterized in that: It also includes a sensor data measurement unit; the sensor data measurement unit includes a reference voltage source, a voltage stabilization circuit and at least one measurement circuit; The reference voltage source is connected to the input terminal of the voltage stabilizing circuit to provide a reference voltage level to the voltage stabilizing circuit; The output end of the voltage stabilizing circuit is used to be connected to the power supply end of at least one sensor to be tested, so as to supply power to at least one sensor to be tested according to the reference level; The input end of the measuring circuit is used to be connected to the output end of the sensor to be tested to receive the sensing signal output by the sensor to be tested, and the output end of the measuring circuit is used to output a sensing measurement result representing the size of the sensing signal.

8. The analog quantity acquisition module according to claim 7, characterized in that: The measurement circuit further includes a reference terminal connected to the reference voltage source to receive the reference level.

9. An analog quantity acquisition device, characterized in that: It comprises the analog quantity acquisition module as described in any one of claims 1-8.

10. A rapid prototyping device, characterized in that: It comprises the analog quantity acquisition device as claimed in claim 9, wherein the analog quantity acquisition device is connected to the object to be measured to collect analog quantity data from the object to be measured.

Images