Temperature acquisition circuit and motor device
By adopting a two-stage differential amplification module and a first-stage differential module in the temperature acquisition circuit, and setting up switching units and feedback resistors matching multiple thermal resistance types, the problem of designing different temperature acquisition circuits for different types of thermal resistances in the prior art is solved, achieving higher temperature acquisition accuracy and lower cost.
Patent Information
- Application Number
- CN202510075863.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-06-17
AI Technical Summary
In the prior art, different temperature acquisition circuits need to be designed for different types of temperature thermal resistance, resulting in diversified product types and inconvenient for normalization processing.
The temperature acquisition is carried out in the two-stage differential amplification module and the first-stage differential module, and the switching units and feedback resistors matching multiple thermal resistance types are set up in each stage of the differential amplification module, so that the temperature acquisition circuit can adapt to different types of thermal resistances.
It improves the accuracy of temperature acquisition, reduces design costs and hardware costs, improves the practicality of temperature acquisition circuits, facilitates R&D and production management, and reduces the probability of production or market errors.
Smart Images
Figure CN120160720A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of temperature acquisition, in particular to a temperature acquisition circuit and a motor device. Background Art
[0002] As is well known, hardware devices will generate corresponding temperatures during operation, so temperature detection is required for adjustment according to the temperature. For example, a motor is a magnetic device with many internal cables. If the motor temperature is too high, it will cause magnetic failure and damage to the cable outer skin, resulting in serious accidents such as motor cable short circuit and motor damage. Therefore, motor temperature detection is particularly important. The motor temperature thermal resistor is a key device for collecting the internal temperature of the motor. When the motor temperature rises or falls, the resistance value of the temperature thermal resistor also changes accordingly. This change in resistance value is converted into an electrical signal and then sent to a processor for related processing.
[0003] There are many types of temperature thermal resistors. In practical applications, different temperature acquisition circuit schemes need to be used for different temperature thermal resistors, resulting in a variety of product types and making it inconvenient for product normalization processing. Summary of the Invention
[0004] The present application provides a temperature acquisition circuit and a motor device, which can make the temperature acquisition circuit adapt to different types of thermal resistors.
[0005] In a first aspect, the present application provides a temperature acquisition circuit, which includes: a first differential amplification module for coupling to both ends of a target thermal resistor and generating a first differential amplification signal based on an input voltage; wherein, the first differential amplification module includes a plurality of first switch units and feedback resistors, and each first switch unit corresponds to at least one type of thermal resistor and a feedback resistor; a second differential amplification module coupled to the first differential amplification module, receiving the first differential amplification signal, and generating a second differential amplification signal; wherein, the second differential amplification module includes a plurality of second switch units and feedback resistors, and each second switch unit corresponds to at least one type of thermal resistor and a feedback resistor; a differential module coupled to the second differential amplification module, receiving the second differential amplification signal, and generating an output voltage; a processing module respectively coupled to the first differential amplification module, the second differential amplification module, and the differential module, receiving the output voltage, and obtaining the temperature corresponding to the target thermal resistor based on the output voltage; during the temperature acquisition process, the processing module controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor to conduct, so that the corresponding feedback resistor is connected into the temperature acquisition loop.
[0006] Among them, the first differential amplification module further includes: a first differential amplification unit, the positive input terminal of the first differential amplification unit is coupled to the first end of the target thermal resistor, and the output terminal of the first differential amplification unit is coupled to the second differential amplification module; a second differential amplification unit, the positive input terminal of the second differential amplification unit is coupled to the second end of the target thermal resistor, and the output terminal of the second differential amplification unit is coupled to the second differential amplification module; wherein, the negative input terminal of the first differential amplification unit is coupled to the first end of each switching unit through a feedback resistor, and the second end of each switching unit is coupled to the negative input terminal of the second differential amplification unit; during the temperature acquisition process, the processing module controls the first switching unit corresponding to the type of the target thermal resistor to conduct, so that the negative input terminal of the first differential amplification unit is coupled to the negative input terminal of the second differential amplification unit through the first switching unit.
[0007] Among them, each first switching unit includes: a switching device, the first end of the switching device is coupled to the negative input terminal of the first differential amplification unit through a feedback resistor, and the second end of the switching device is coupled to the negative input terminal of the second differential amplification unit; a voltage dividing and filtering component, the first end of the voltage dividing and filtering component is coupled to the control terminal of the switching device, the second end of the voltage dividing and filtering component is grounded, and the third end of the voltage dividing and filtering component is coupled to the processing module.
[0008] Among them, the first differential amplification module further includes: a first resistor, the first end of the first resistor is coupled to the output terminal of the first differential amplification unit, and the second end of the first resistor is coupled to the negative input terminal of the first differential amplification unit; a second resistor, the first end of the second resistor is coupled to the output terminal of the second differential amplification unit, and the second end of the second resistor is coupled to the negative input terminal of the second differential amplification unit.
[0009] Among them, the second differential amplification module further includes: a third differential amplification unit, the positive input terminal of the third differential amplification unit is coupled to the first output terminal of the first differential amplification module, and the output terminal of the third differential amplification unit is coupled to the differential module; a fourth differential amplification unit, the positive input terminal of the fourth differential amplification unit is coupled to the second output terminal of the first differential amplification module, and the output terminal of the fourth differential amplification unit is coupled to the differential module; during the temperature acquisition process, the processing module controls the second switching unit corresponding to the type of the target thermal resistor to conduct, so that the negative input terminal of the third differential amplification unit is coupled to the negative input terminal of the fourth differential amplification unit through the second switching unit.
[0010] Among them, each second switching unit includes: a switching device, the first end of the switching device is coupled to the negative input terminal of the third differential amplification unit through a feedback resistor, and the second end of the switching device is coupled to the negative input terminal of the fourth differential amplification unit; a voltage dividing and filtering component, the first end of the voltage dividing and filtering component is coupled to the control terminal of the switching device, the second end of the voltage dividing and filtering component is grounded, and the third end of the voltage dividing and filtering component is coupled to the processing module.
[0011] Among them, the second differential amplification module further includes: a third resistor, the first end of the third resistor is coupled to the output end of the third differential amplification unit, and the second end of the third resistor is coupled to the negative input end of the third differential amplification unit; a fourth resistor, the first end of the fourth resistor is coupled to the output end of the fourth differential amplification unit, and the second end of the fourth resistor is coupled to the negative input end of the fourth differential amplification unit.
[0012] Among them, the temperature acquisition circuit further includes: a common-mode inductor, the first input end of the common-mode inductor is coupled to the first end of the target thermal resistor, and the second input end of the common-mode inductor is coupled to the second end of the target thermal resistor; a first capacitor, the first capacitor is connected in parallel between the first output end and the second output end of the common-mode inductor, and the first input end and the second input end of the first differential amplification module.
[0013] Among them, the temperature acquisition circuit further includes: an input voltage providing module, the input voltage providing module is connected in parallel across the two ends of the target thermal resistor, and provides an input voltage to the first differential amplification module.
[0014] In a second aspect, the present application provides a motor device, and the motor device includes the temperature acquisition circuit provided in the first aspect.
[0015] The beneficial effects of the present application are: Different from the prior art, the temperature acquisition circuit and the motor device provided by the present application use a two-stage differential amplification module and a one-stage differential module for temperature acquisition, which can improve the accuracy of temperature acquisition, and a switching unit and a feedback resistor matching multiple types of thermal resistors are provided in each stage of the differential amplification module, so that the temperature acquisition circuit can be adapted to different types of thermal resistors, without separately designing a temperature acquisition circuit for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit, and also facilitating the research and development and production management of the temperature acquisition circuit, improving the product use efficiency and market adaptability, avoiding the production or market error probability caused by multiple previous versions of the temperature acquisition circuit, and thus achieving the effect of reducing costs. Description of the Drawings
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:
[0017] Figure 1 is a schematic structural diagram of an embodiment of the temperature acquisition circuit provided by the present application;
[0018] Figure 2 is a schematic structural diagram of another embodiment of the temperature acquisition circuit provided by the present application;
[0019] Figure 3 It is a schematic structural diagram of another embodiment of the temperature acquisition circuit provided by this application;
[0020] Figure 4 It is a schematic structural diagram of another embodiment of the temperature acquisition circuit provided by this application;
[0021] Figure 5 and Figure 6 It is a schematic structural diagram of another embodiment of the temperature acquisition circuit provided by this application;
[0022] Figure 7 It is a schematic structural diagram of an embodiment of the motor device provided by this application. Specific Embodiments
[0023] Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this application. It can be understood that the specific embodiments described herein are only used to explain this application, rather than limiting this application. Additionally, it should be noted that for the convenience of description, only parts related to this application rather than all structures are shown in the accompanying drawings. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by this application.
[0024] Referring to "embodiments" herein means that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.
[0025] As is well known, hardware devices will generate corresponding temperatures during operation, so temperature detection is required for adjustment according to the temperature. For example, a motor is a magnetic device with many internal cables. If the motor temperature is too high, it will cause magnetic failure and cable sheath damage, which will further lead to serious accidents such as motor cable short circuits and motor damage. Therefore, motor temperature detection is particularly important. The motor temperature thermal resistor is a key device for collecting the internal temperature of the motor. When the motor temperature rises or falls, the resistance value of the temperature thermal resistor also changes accordingly. This change in resistance value is converted into an electrical signal and then sent to the processor for relevant processing.
[0026] There are many types of temperature thermal resistors. In actual applications, different temperature acquisition circuit solutions need to be used for different temperature thermal resistors, resulting in a variety of product types and making it inconvenient for product normalization processing.
[0027] Based on this, the present application proposes to use a two-stage differential amplification module and a one-stage differential module for temperature acquisition, which can improve the accuracy of temperature acquisition. And a switching unit and a feedback resistor matching multiple types of thermal resistors are set in each stage of the differential amplification module, so that the temperature acquisition circuit can adapt to different types of thermal resistors, without the need to separately design a temperature acquisition circuit for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit, and also facilitating the research and development and production management of the temperature acquisition circuit, improving the product use efficiency and market adaptability, avoiding the probability of production or market errors caused by previous multiple versions of the temperature acquisition circuit, and thus achieving the effect of cost reduction, and solving at least one of the above technical problems. For specific reference, see the following embodiments.
[0028] Refer to Figure 1 , Figure 1 FIG. is a schematic structural diagram of an embodiment of the temperature acquisition circuit provided by the present application. The temperature acquisition circuit 1000 includes: a first differential amplification module 100, a second differential amplification module 200, a differential module 300, and a processing module 400.
[0029] Among them, the first differential amplification module 100 is used to couple the two ends of the target thermal resistor A and generate a first differential amplified signal according to the input voltage. Among them, the first differential amplification module 100 includes a plurality of first switching units and feedback resistors, and each first switching unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0030] In some embodiments, the target thermal resistor A may be at least one of NTC103, NTC104, PT100, PT1000, etc.
[0031] Among them, the central values and full-range (-40°C to +180°C) resistance values of NTC103, NTC104, PT100, and PT1000 are as follows:
[0032] NTC104: 25°C / 100KΩ, 4035.66KΩ to 1072Ω.
[0033] NTC103: 25°C / 10KΩ, 403.5KΩ to 107Ω.
[0034] PT1000: 0°C / 1KΩ, 846Ω to 1693Ω.
[0035] PT100: 0°C / 100Ω, 85Ω to 169Ω.
[0036] In some embodiments, the target thermal resistor A may be disposed on one side of the measured target for collecting the corresponding temperature of the measured target.
[0037] In some embodiments, the resistance values of the feedback resistors corresponding to different types of thermal resistors may be different. In some embodiments, the resistance values of the feedback resistors corresponding to some types of thermal resistors may be the same.
[0038] The second differential amplification module 200 is coupled to the first differential amplification module 100, receives the first differential amplification signal, and generates a second differential amplification signal. Among them, the second differential amplification module 200 includes a plurality of second switch units and feedback resistors, and each second switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0039] In some embodiments, the first differential amplification module 100 and the second differential amplification module 200 may be any one of the following types:
[0040] A differential amplifier with dual-input and dual-output;
[0041] A differential amplifier with dual-input and single-output;
[0042] A differential amplifier with single-input and dual-output;
[0043] A differential amplifier with single-input and single-output.
[0044] In some embodiments, both the first differential amplification module 100 and the second differential amplification module 200 may be differential amplifiers with dual-input and dual-output.
[0045] In some embodiments, both the first differential amplification module 100 and the second differential amplification module 200 may be differential amplifiers with single-input and single-output.
[0046] In some embodiments, the first differential amplification module 100 may be a differential amplifier with single-input and dual-output, and the second differential amplification module 200 may be a differential amplifier with dual-input and single-output or a differential amplifier with dual-input and dual-output.
[0047] In some embodiments, the first differential amplification module 100 may be a differential amplifier with single-input and single-output, and the second differential amplification module 200 may be a differential amplifier with single-input and dual-output.
[0048] The differential module 300 is coupled to the second differential amplification module 200, receives the second differential amplification signal, and generates an output voltage.
[0049] The processing module 400 is respectively coupled to the first differential amplification module 100, the second differential amplification module 200, and the differential module 300, receives the output voltage, and obtains the temperature corresponding to the target thermal resistor A based on the output voltage.
[0050] During the temperature acquisition process, the processing module 400 controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor A to conduct, so that the corresponding feedback resistor is connected into the temperature acquisition circuit.
[0051] In some embodiments, corresponding first switch units and feedback resistors can be set for each type of thermal resistor in the first differential amplification module 100. Corresponding second switch units and feedback resistors can be set for each type of thermal resistor in the second differential amplification module 200.
[0052] In some embodiments, the temperature acquisition circuit 1000 further includes several capacitors with filtering functions, and the capacitors are arranged at corresponding nodes to filter the entire temperature acquisition process.
[0053] In this embodiment, the temperature is acquired by using two-stage differential amplification modules and one-stage differential module, which can improve the accuracy of temperature acquisition. And by setting switch units and feedback resistors matching multiple types of thermal resistors in each stage of differential amplification module, the temperature acquisition circuit 1000 can be adapted to different types of thermal resistors, without separately designing the temperature acquisition circuit 1000 for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit 1000. Similarly, it is convenient for the research and development and production management of the temperature acquisition circuit 1000, improving the product use efficiency and market adaptability, and avoiding the production or market error probability caused by multiple previous versions of the temperature acquisition circuit 1000, thus achieving the effect of cost reduction.
[0054] Refer to Figure 2 , Figure 2 FIG. is a schematic structural diagram of another embodiment of the temperature acquisition circuit 1000 provided by the present application. The temperature acquisition circuit includes: a first differential amplification module 100, a second differential amplification module 200, a differential module 300, and a processing module 400.
[0055] Among them, the first differential amplification module 100 is used to couple the two ends of the target thermal resistor A and generate a first differential amplification signal according to the input voltage. Among them, the first differential amplification module 100 includes a first differential amplification unit U34, a second differential amplification unit U16, several first switch units, and feedback resistors. Among them, each first switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0056] In some embodiments, taking the thermal resistor types of NTC103, NTC104, PT100, and PT1000 as examples, a first switch unit and a corresponding feedback resistor can be set for each of NTC103, NTC104, PT100, and PT1000, that is, a total of 4 first switch units are set.
[0057] In some embodiments, if the types of the thermal resistors are NTC103, NTC104, PT100, and PT1000 for example, a first switching unit may be provided for both PT100 and PT1000, and a common first switching unit and corresponding feedback resistors may be provided for NTC103 and NTC104. That is, a total of 3 first switching units are provided.
[0058] Among them, the positive input terminal of the first differential amplification unit U34 is coupled to the first end of the target thermal resistor A, and the output terminal of the first differential amplification unit U34 is coupled to the second differential amplification module 200.
[0059] The positive input terminal of the second differential amplification unit U16 is coupled to the second end of the target thermal resistor A, and the output terminal of the second differential amplification unit U16 is coupled to the second differential amplification module 200.
[0060] Among them, the negative input terminal of the first differential amplification unit U34 is coupled to the first end of each switching unit through a feedback resistor, and the second end of each switching unit is coupled to the negative input terminal of the second differential amplification unit U16.
[0061] During the temperature acquisition process, the processing module 400 controls the first switching unit corresponding to the type of the target thermal resistor A to conduct, so that the negative input terminal of the first differential amplification unit U34 is coupled to the negative input terminal of the second differential amplification unit U16 through the first switching unit.
[0062] In some embodiments, each first switching unit includes: a switching device and a voltage-dividing and filtering component.
[0063] The first end of the switching device is coupled to the negative input terminal of the first differential amplification unit U34 through a feedback resistor, and the second end of the switching device is coupled to the negative input terminal of the second differential amplification unit U16. The first end of the voltage-dividing and filtering component is coupled to the control terminal of the switching device, the second end of the voltage-dividing and filtering component is grounded, and the third end of the voltage-dividing and filtering component is coupled to the processing module 400.
[0064] In some embodiments, the voltage-dividing and filtering component may be composed of several resistors and capacitors.
[0065] Furthermore, the first differential amplification module 100 further includes: a first resistor (not shown in the figure) and a second resistor. The first end of the first resistor is coupled to the output terminal of the first differential amplification unit U34, and the second end of the first resistor is coupled to the negative input terminal of the first differential amplification unit U34. The first end of the second resistor is coupled to the output terminal of the second differential amplification unit U16, and the second end of the second resistor is coupled to the negative input terminal of the second differential amplification unit U16.
[0066] The second differential amplification module 200 is coupled to the first differential amplification unit U34 and the second differential amplification unit U16, receives the differential amplification signals output by the first differential amplification unit U34 and the second differential amplification unit U16 respectively, and generates a second differential amplification signal. Among them, the second differential amplification module 200 includes a plurality of second switch units and feedback resistors, and each second switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0067] The differential module 300 is coupled to the second differential amplification module 200, receives the second differential amplification signal, and generates an output voltage.
[0068] The processing module 400 is respectively coupled to the first differential amplification module 100, the second differential amplification module 200 and the differential module 300, receives the output voltage, and obtains the temperature corresponding to the target thermal resistor A according to the output voltage.
[0069] During the temperature acquisition process, the processing module 400 controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor A to be turned on, so that the corresponding feedback resistor is connected into the temperature acquisition circuit.
[0070] In this embodiment, the temperature acquisition is performed by using a two-stage differential amplification module and a one-stage differential module, which can improve the accuracy of temperature acquisition. And in each stage of the differential amplification module, switch units and feedback resistors matching multiple types of thermal resistors are set, so that the temperature acquisition circuit 1000 can adapt to different types of thermal resistors, without separately designing the temperature acquisition circuit 1000 for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit 1000, and also facilitating the research and development and production management of the temperature acquisition circuit 1000, improving the product use efficiency and market adaptability, and avoiding the production or market error probability caused by multiple previous versions of the temperature acquisition circuit 1000, thereby achieving the effect of reducing costs.
[0071] Refer to Figure 3 , Figure 3 FIG. is a schematic structural diagram of another embodiment of the temperature acquisition circuit provided by the present application. The temperature acquisition circuit includes: a first differential amplification module 100, a second differential amplification module 200, a differential module 300 and a processing module 400.
[0072] Among them, the first differential amplification module 100 is used to be coupled to both ends of the target thermal resistor A and generate a first differential amplification signal according to the input voltage. Among them, the first differential amplification module 100 includes a plurality of first switch units and feedback resistors, and each first switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0073] The second differential amplification module 200 is coupled to the first differential amplification module 100, receives the first differential amplification signal, and generates a second differential amplification signal. Among them, the second differential amplification module 200 includes a third differential amplification unit U27, a fourth differential amplification unit U54, a plurality of second switch units, and feedback resistors. Each second switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0074] In some embodiments, taking the thermal resistor types of NTC103, NTC104, PT100, and PT1000 as examples, a second switch unit and a corresponding feedback resistor can be set for each of NTC103, NTC104, PT100, and PT1000. That is, a total of 4 second switch units are set.
[0075] In some embodiments, taking the thermal resistor types of NTC103, NTC104, PT100, and PT1000 as examples, a second switch unit can be shared for PT100 and PT1000, and a second switch unit can be shared for NTC103 and NTC104, as well as corresponding feedback resistors. That is, a total of 2 first switch units are set.
[0076] Among them, the positive input terminal of the third differential amplification unit U27 is coupled to the first output terminal of the first differential amplification module 100, and the output terminal of the third differential amplification unit U27 is coupled to the differential module 300.
[0077] The positive input terminal of the fourth differential amplification unit U54 is coupled to the second output terminal of the first differential amplification module 100, and the output terminal of the fourth differential amplification unit U54 is coupled to the differential module 300.
[0078] During the temperature acquisition process, the processing module 400 controls the second switch unit corresponding to the type of the target thermal resistor A to conduct, so that the negative input terminal of the third differential amplification unit U27 is coupled to the negative input terminal of the fourth differential amplification unit U54 through the second switch unit.
[0079] In some embodiments, each second switch unit includes: a switching device and a voltage dividing and filtering component. The first end of the switching device is coupled to the negative input terminal of the third differential amplification unit U27 through a feedback resistor, and the second end of the switching device is coupled to the negative input terminal of the fourth differential amplification unit U54. The first end of the voltage dividing and filtering component is coupled to the control end of the switching device, the second end of the voltage dividing and filtering component is grounded, and the third end of the voltage dividing and filtering component is coupled to the processing module 400.
[0080] In some embodiments, the second differential amplification module 200 further includes: a third resistor and a fourth resistor.
[0081] The first end of the third resistor is coupled to the output end of the third differential amplifier unit U27, and the second end of the third resistor is coupled to the negative input end of the third differential amplifier unit U27; a fourth resistor, the first end of the fourth resistor is coupled to the output end of the fourth differential amplifier unit U54, and the second end of the fourth resistor is coupled to the negative input end of the fourth differential amplifier unit U54.
[0082] The differential module 300 is coupled to the third differential amplifier unit U27 and the fourth differential amplifier unit U54, receives the differential amplification signals output by the third differential amplifier unit U27 and the fourth differential amplifier unit U54 respectively, and generates an output voltage. For example, the positive input end of the differential module 300 is coupled to the output end of the fourth differential amplifier unit U54, and the negative input end of the differential module 300 is coupled to the output end of the third differential amplifier unit U27.
[0083] The processing module 400 is respectively coupled to the first differential amplification module 100, the second differential amplification module 200 and the differential module 300, receives the output voltage, and obtains the temperature corresponding to the target thermal resistor A according to the output voltage.
[0084] During the temperature acquisition process, the processing module 400 controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor A to conduct, so that the corresponding feedback resistor is connected into the temperature acquisition circuit.
[0085] In this embodiment, the temperature acquisition is performed by using two-stage differential amplification modules and one-stage differential module, which can improve the accuracy of temperature acquisition. And in each stage of differential amplification module, the switch unit and the feedback resistor matching multiple types of thermal resistors are set, so that the temperature acquisition circuit 1000 can adapt to different types of thermal resistors, without separately designing the temperature acquisition circuit 1000 for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit 1000. Similarly, it is convenient for the research and development and production management of the temperature acquisition circuit 1000, improving the product use efficiency and market adaptability, and avoiding the production or market error probability caused by multiple previous versions of the temperature acquisition circuit 1000, thereby achieving the effect of reducing costs.
[0086] Refer to Figure 4 , Figure 4 FIG. is a schematic structural diagram of another embodiment of the temperature acquisition circuit 1000 provided by the present application. The temperature acquisition circuit 1000 includes: a common-mode inductor L17, a first capacitor, an input voltage providing module 500, a first differential amplification module 100, a second differential amplification module 200, a differential module 300 and a processing module 400.
[0087] The first input terminal of the common-mode inductor L17 is coupled to the first end of the target thermal resistor A, and the second input terminal of the common-mode inductor L17 is coupled to the second end of the target thermal resistor A. The common-mode inductor L17 is used to filter the temperature signal of the target thermal resistor A to remove interference.
[0088] The first capacitor is connected in parallel between the first output terminal and the second output terminal of the common-mode inductor L17, and the first input terminal and the second input terminal of the first differential amplification module 100. The first capacitor also has a filtering function.
[0089] The input voltage providing module 500 is connected in parallel across the two ends of the target thermal resistor A to provide an input voltage to the first differential amplification module 100. That is, the input voltage providing module 500 can be composed of several resistors connected in series. At least one resistor in the input voltage providing module 500 is connected in parallel with the target thermal resistor A through the common-mode inductor L17. The voltage across the at least one resistor is the input voltage provided to the first differential amplification module 100.
[0090] The first differential amplification module 100 generates a first differential amplification signal based on the input voltage. Among them, the first differential amplification module 100 includes several first switch units and feedback resistors, and each first switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0091] The second differential amplification module 200 is coupled to the first differential amplification module 100, receives the first differential amplification signal, and generates a second differential amplification signal. Among them, the first differential amplification module 100 includes several second switch units and feedback resistors, and each second switch unit corresponds to at least one type of thermal resistor and a feedback resistor.
[0092] The differential module 300 is coupled to the second differential amplification module 200, receives the second differential amplification signal, and generates an output voltage.
[0093] The processing module 400 is respectively coupled to the first differential amplification module 100, the second differential amplification module 200, and the differential module 300, receives the output voltage, and obtains the temperature corresponding to the target thermal resistor A based on the output voltage.
[0094] During the temperature acquisition process, the processing module 400 controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor A to conduct, so that the corresponding feedback resistor is connected into the temperature acquisition circuit.
[0095] In this embodiment, temperature acquisition is performed by using a two-stage differential amplification module and a one-stage differential module, which can improve the accuracy of temperature acquisition. And a switching unit and a feedback resistor matching multiple types of thermal resistors are set in each differential amplification module, so that the temperature acquisition circuit 1000 can adapt to different types of thermal resistors, without separately designing the temperature acquisition circuit 1000 for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit 1000, and also facilitating the research and development and production management of the temperature acquisition circuit 1000, improving the product usage efficiency and market adaptability, and avoiding the probability of production or market errors caused by previous multiple versions of the temperature acquisition circuit 1000, thereby achieving the effect of cost reduction.
[0096] Refer to Figure 5 and Figure 6 , Figure 5 and Figure 6 FIG. and FIG. are schematic structural diagrams of another embodiment of the temperature acquisition circuit 1000 provided by the present application. The temperature acquisition circuit 1000 includes: common mode inductor L17, capacitor C7, capacitor C15, capacitor C279, capacitor C307, capacitor C287, capacitor C286, capacitor C223, capacitor C310, capacitor C309, capacitor C308, capacitor C311, capacitor C212, capacitor C211, capacitor C44, capacitor C210, capacitor C283, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, resistor R10, resistor R11, resistor R12, resistor R13, resistor R16, resistor R20, resistor R21, resistor R22, resistor R342, resistor R369, resistor R382, resistor R375, resistor R371, resistor R370, resistor R377, resistor R196, resistor R35, resistor R34, resistor R15, resistor R39, transistor Q13, transistor Q14, transistor Q18, transistor Q28, transistor Q29, first differential amplification unit U34, second differential amplification unit U16, third differential amplification unit U27, fourth differential amplification unit U54, differential module U35.
[0097] Wherein, the first input end of the common mode inductor L17 is coupled to the first end of the target thermal resistor A, and the second input end of the common mode inductor L17 is coupled to the second end of the target thermal resistor A.
[0098] Capacitor C7 is connected in parallel between the first output end and the second output end of the common mode inductor L17, and the first input end and the second input end of the first differential amplification module 100.
[0099] The voltage source VIN, the series-connected resistors R4, R6 and R5 constitute the above-mentioned input voltage providing module 500. Among them, resistor R6 is connected in parallel with the first capacitor.
[0100] The first differential amplification unit U34, the second differential amplification unit U16, the transistor Q13, the resistor R13, the resistor R12, and the capacitor C44, the transistor Q13, the resistor R13, the resistor R12, and the capacitor C44, the transistor Q18, the resistor R22, the resistor R21, and the capacitor C212, the resistor R7, the resistor R8, the resistor R9, the resistor R10, and the resistor R11 constitute the above-mentioned first differential amplification module 100.
[0101] Among them, the transistor Q13, the resistor R13, the resistor R12, and the capacitor C44 can form a switching unit. Among them, the control end of the transistor Q13 is coupled to the processing module 400 through the resistor R13.
[0102] The transistor Q14, the resistor R20, the resistor R16, and the capacitor C211 can form a switching unit. Among them, the control end of the transistor Q14 is coupled to the processing module 400 through the resistor R20.
[0103] The transistor Q18, the resistor R22, the resistor R21, and the capacitor C212 can form a switching unit. Among them, the control end of the transistor Q18 is coupled to the processing module 400 through the resistor R22.
[0104] Among them, the positive input end of the first differential amplification unit U34 is coupled to the first end of the resistor R6, and the negative input end of the first differential amplification unit U34 is coupled to the first ends of the resistor R7, the resistor R9, the resistor R10, and the resistor R11. The positive input end of the first differential amplification unit U34 is grounded through the capacitor C15.
[0105] The output end of the first differential amplification unit U34 is coupled to the second end of the resistor R7. The first voltage end of the first differential amplification unit U34 is grounded, and the second voltage end of the first differential amplification unit U34 is grounded through the capacitor C279.
[0106] Among them, the positive input end of the second differential amplification unit U16 is coupled to the second end of the resistor R6, and the negative input end of the second differential amplification unit U16 is coupled to the second ends of the transistors Q13, Q14, Q18, and the first end of the resistor R8.
[0107] The output end of the second differential amplification unit U16 is coupled to the second end of the resistor R8. The first voltage end of the second differential amplification unit U16 is grounded, and the second voltage end of the second differential amplification unit U16 is grounded through the capacitor C210. The positive input end of the second differential amplification unit U16 is grounded through the capacitor C283. The output ends of the first differential amplification unit U34 and the second differential amplification unit U16 are coupled through the capacitor C311.
[0108] The third differential amplification unit U27, the fourth differential amplification unit U54, the transistor Q28, the resistor R375, the resistor R371, and the capacitor C309, the transistor Q29, the resistor R370, the resistor R377, the capacitor C310, the diode assembly, the resistor R342, the resistor R196, the resistor R369, and the resistor R382 constitute the second differential amplification module 200 described above.
[0109] Among them, the transistor Q28, the resistor R375, the resistor R371, and the capacitor C309 can form a switching unit, such as the second switching unit described above. Among them, the control terminal of the transistor Q28 is coupled to the processing module 400 through the resistor R375.
[0110] The transistor Q29, the resistor R370, the resistor R377, the capacitor C310, and the diode assembly can form a switching unit, such as the second switching unit described above. Among them, the control terminal of the transistor Q29 is coupled to the processing module 400 through the resistor R370 and the diode assembly.
[0111] Among them, the positive input terminal of the third differential amplification unit U27 is coupled to the output terminal of the first differential amplification unit U34, and the negative input terminal of the third differential amplification unit U27 is coupled to the first terminal of the resistor R342, the first terminals of the resistor R369 and the resistor R382. That is, the positive input terminal of the third differential amplification unit U27 receives the signal V1.
[0112] The output terminal of the third differential amplification unit U27 is coupled to the second terminal of the resistor R342. The first voltage terminal of the third differential amplification unit U27 is grounded, and the second voltage terminal of the third differential amplification unit U27 is grounded through the capacitor C307.
[0113] Among them, the positive input terminal of the fourth differential amplification unit U54 is coupled to the output terminal of the second differential amplification unit U16, and the negative input terminal of the fourth differential amplification unit U54 is coupled to the first terminals of the transistor Q28, the transistor Q29, and the resistor R196. That is, the positive input terminal of the fourth differential amplification unit U54 receives the signal V2. That is, the signal V1 and the signal V2 constitute the second differential amplification signal described above.
[0114] The output terminal of the fourth differential amplification unit U54 is coupled to the second terminal of the resistor R196. The first voltage terminal of the fourth differential amplification unit U54 is grounded, and the second voltage terminal of the fourth differential amplification unit U54 is grounded through the capacitor C308.
[0115] The positive input terminal of the differential module U35 is coupled to the output terminal of the fourth differential amplification unit U54 through the resistor R35. The negative input terminal of the differential module U35 is coupled to the output terminal of the third differential amplification unit U27 through the resistor R34. A capacitor C223 is connected in parallel between the positive input terminal and the negative input terminal of the differential module U35. The first voltage terminal of the differential module U35 is grounded, and the second voltage terminal of the differential module U35 is grounded through the capacitor C287. The negative input terminal of the differential module U35 is coupled to the output terminal of the differential module U35 through the resistor R15. The positive input terminal of the differential module U35 is grounded through the resistor R24.
[0116] The first end of the resistor R38 is coupled to the output terminal of the differential module U35, the first end of the capacitor C286 is coupled to the second end of the resistor R38, and the second end of the capacitor C286 is grounded.
[0117] The second end of the resistor R38 is coupled to the processing module 400.
[0118] The processing module 400 is respectively coupled to the control terminals of the transistor Q13, the transistor Q14, the transistor Q18, the transistor Q28, the transistor Q29 and the differential module U35, receives the output voltage, and obtains the temperature corresponding to the target thermal resistor A according to the output voltage. That is, the processing module 400 receives the output voltage V OUT 。
[0119] During the temperature acquisition process, the processing module 400 controls the conduction of the transistor corresponding to the type of the target thermal resistor A, so that the corresponding feedback resistor is connected into the temperature acquisition loop.
[0120] For example, when the target thermal resistor A is PT1000, the processing module 400 respectively sends control signals PT1000_SEL to the transistor Q13 and the transistor Q29 to make the transistor Q13 and the transistor Q29 conduct, and completes the temperature acquisition.
[0121] When the target thermal resistor A is PT100, the processing module 400 respectively sends control signals PT100_SEL to the transistor Q14 and the transistor Q29 to make the transistor Q14 and the transistor Q29 conduct, and completes the temperature acquisition.
[0122] When the target thermal resistor A is NTC103, the processing module 400 respectively sends control signals NTC103 / 104_SEL to the transistor Q18 and the transistor Q28 to make the transistor Q18 and the transistor Q28 conduct, and completes the temperature acquisition.
[0123] When the target thermal resistor A is NTC104, the processing module 400 respectively sends control signals NTC103 / 104_SEL to the transistor Q18 and the transistor Q28 to make the transistor Q18 and the transistor Q28 conduct, and completes the temperature acquisition.
[0124] In an application scenario, the above-mentioned thermal resistor can be applied to a motor to collect the operating temperature of the motor, such as collecting the temperature of the motor winding. Since the motor itself has a lot of interference, it is first filtered by the common-mode inductor L17, and then the interference is filtered out by the capacitor C7. A power supply VIN is connected in series with three resistors R4, R5, and R6. The resistor R6 is connected in parallel with the motor thermal resistor through the common-mode inductor L17, and the resistor after parallel connection is defined as R T , R T The voltage across both ends is the input end of the first-stage high-precision differential amplifier circuit (such as the first differential amplifier module 100 mentioned above). The second differential amplifier unit U16 and the first differential amplifier unit U34 are two operational amplifiers of the first-stage high-precision differential amplifier circuit. The capacitors C15 and C283 are filter capacitors, and the capacitors C279 and C210 are decoupling capacitors of the operational amplifier. The resistors R7 and R8 respectively form PT1000, PT100, NTC103, and NTC104 feedback resistors with the resistors R9, R10, and R11. Among them, the resistor R11 is compatible with the feedback resistors of NTC103 and NTC104. When the motor thermal resistor is confirmed to be one of these four models, as long as the DSP (such as the processing module 400 mentioned above) sends a signal to the corresponding transistor Q13, transistor Q14, or transistor Q18, and makes the resistors R9, R10, and R11 be connected in parallel to the circuit. Each resistor of the transistors Q13, Q14, and Q18 has a corresponding gate voltage-dividing resistor and filter capacitor to enable it to conduct smoothly.
[0125] The capacitor C311 is also a filter capacitor and is sent to the input end of the second-stage high-precision differential amplifier circuit later. The third differential amplifier unit U27 and the fourth differential amplifier unit U54 are the operational amplifiers of the second-stage high-precision differential amplifier circuit. The capacitors C307 and C308 are the decoupling capacitors of the third differential amplifier unit U27 and the fourth differential amplifier unit U54. The resistors R196 and R342 respectively form PT1000, PT100, NTC103, and NTC104 feedback resistors with the resistors R369 and R382. Among them, the resistor R369 is compatible with the feedback resistors of NTC103 and NTC104. The resistor R382 is compatible with the feedback resistors of PT1000 and PT100. The signals of PT1000 and PT100 are sent to the transistor through an OR gate composed of diodes. When the motor thermal resistor is confirmed to be one of these four models, as long as the DSP sends a signal to the corresponding transistor Q28 or transistor Q29, and makes the resistors R369 and R382 be connected in parallel to the circuit. Each resistor of the transistors Q28 and Q29 has a corresponding gate voltage-dividing resistor and filter capacitor to enable it to conduct smoothly.
[0126] Finally, there is a first - order differential circuit (such as the differential module U35 and the differential module 300 mentioned above). U35 is the operational amplifier of this differential circuit, and the capacitor C287 is the decoupling capacitor of U35. The resistors R15, R24, R34, and R35 form the input and feedback resistors. The differential output is sent to the DSP through the RC filter circuit composed of the resistor R39 and the capacitor C286.
[0127] The operational formula of this circuit is as follows, where R4 = R5, R7 = R8, R196 = R342, R15 = R24, R34 = R35, R T1 = R9 or R10 or R11, R T2 = R369 or R382:
[0128]
[0129] During the working process, the corresponding transistors are turned on according to the type of the thermal resistor, the appropriate resistance value is matched, and the result is calculated through this formula, which can ensure that this circuit can accurately sample the four types of temperature thermal resistors, namely PT1000, PT100, NTC103, and NTC104, within the full temperature range.
[0130] In any of the above - mentioned embodiments, all the resistors in the circuit sample with 0.1% accuracy to improve the circuit accuracy. The capacitors use NPO or COG capacitors to avoid the capacitance value deviation caused by temperature, which may affect the circuit accuracy.
[0131] Refer to Figure 7 , Figure 7 which is a schematic structural diagram of an embodiment of the motor device provided by this application. The motor device 70 includes a temperature acquisition circuit 1000.
[0132] In summary, for the temperature acquisition circuit 1000 and the motor device 70 provided by this application, the temperature is acquired by using the method of two - stage differential amplification modules and a first - order differential module 300, which can improve the accuracy of temperature acquisition. And in each stage of the differential amplification module, a switch unit and feedback resistors matching multiple types of thermal resistors are set, so that the temperature acquisition circuit 1000 can adapt to different types of thermal resistors, without the need to separately design the temperature acquisition circuit 1000 for each type of thermal resistor, reducing the design cost and hardware cost, improving the practicability of the temperature acquisition circuit 1000. Similarly, it is convenient for the research and development and production management of the temperature acquisition circuit 1000, improving the product use efficiency and market adaptability, and avoiding the probability of production or market errors caused by previous multiple versions of the temperature acquisition circuit 1000, thus achieving the effect of cost reduction.
[0133] In several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.
[0134] If the integrated unit in the above-mentioned other embodiments is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor 10 (processor) to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.
[0135] The above is only the embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present application.
Claims
1. A temperature acquisition circuit, characterized in that: The temperature acquisition circuit comprises: A first differential amplifier module, used for coupling two ends of a target thermal resistor, and generating a first differential amplifier signal according to an input voltage; wherein the first differential amplifier module comprises a plurality of first switch units and feedback resistors, and each of the first switch units corresponds to at least one type of thermal resistor and one feedback resistor; A second differential amplification module, coupled to the first differential amplification module, receives the first differential amplification signal, and generates a second differential amplification signal; wherein the second differential amplification module includes a plurality of second switch units and feedback resistors, and each of the second switch units corresponds to at least one type of thermal resistor and one feedback resistor; A differential module, coupled to the second differential amplifier module, receives the second differential amplifier signal and generates an output voltage; a processing module, respectively coupled to the first differential amplification module, the second differential amplification module and the differential module, receiving the output voltage, and obtaining a temperature corresponding to the target thermal resistor according to the output voltage; During the temperature acquisition process, the processing module controls the first switch unit and the second switch unit corresponding to the type of the target thermal resistor to be turned on, so that the corresponding feedback resistor is connected to the temperature acquisition loop.
2. The temperature acquisition circuit according to claim 1, characterized in that: The first differential amplifier module comprises: A first differential amplifying unit, wherein a positive input terminal of the first differential amplifying unit is coupled to a first terminal of the target thermal resistor, and an output terminal of the first differential amplifying unit is coupled to the second differential amplifying module; A second differential amplifying unit, wherein a positive input terminal of the second differential amplifying unit is coupled to the second terminal of the target thermal resistor, and an output terminal of the second differential amplifying unit is coupled to the second differential amplifying module; The negative input terminal of the first differential amplifier unit is coupled to the first terminal of each switch unit through a feedback resistor, and the second terminal of each switch unit is coupled to the negative input terminal of the second differential amplifier unit; During the temperature acquisition process, the processing module controls the first switch unit corresponding to the type of the target thermal resistor to be turned on, so that the negative input end of the first differential amplifier unit is coupled to the negative input end of the second differential amplifier unit through the first switch unit.
3. The temperature acquisition circuit according to claim 2, characterized in that: Each of the first switch units comprises: A switch device, wherein a first terminal of the switch device is coupled to the negative input terminal of the first differential amplifier unit through the feedback resistor, and a second terminal of the switch device is coupled to the negative input terminal of the second differential amplifier unit; A voltage-dividing filter component, wherein a first end of the voltage-dividing filter component is coupled to the control end of the switch device, a second end of the voltage-dividing filter component is grounded, and a third end of the voltage-dividing filter component is coupled to the processing module.
4. The temperature acquisition circuit according to claim 2, characterized in that: The first differential amplification module further includes: a first resistor, wherein a first end of the first resistor is coupled to the output end of the first differential amplifier unit, and a second end of the first resistor is coupled to the negative input end of the first differential amplifier unit; A second resistor, wherein a first end of the second resistor is coupled to the output end of the second differential amplifier unit, and a second end of the second resistor is coupled to the negative input end of the second differential amplifier unit.
5. The temperature acquisition circuit according to claim 1, characterized in that: The second differential amplification module comprises: A third differential amplifier unit, wherein a positive input terminal of the third differential amplifier unit is coupled to the first output terminal of the first differential amplifier module, and an output terminal of the third differential amplifier unit is coupled to the differential module; a fourth differential amplifier unit, wherein a positive input terminal of the fourth differential amplifier unit is coupled to the second output terminal of the first differential amplifier module, and an output terminal of the fourth differential amplifier unit is coupled to the differential module; During the temperature acquisition process, the processing module controls the second switch unit corresponding to the type of the target thermal resistor to be turned on, so that the negative input end of the third differential amplifier unit is coupled to the negative input end of the fourth differential amplifier unit through the second switch unit.
6. The temperature acquisition circuit according to claim 5, characterized in that: Each of the second switch units comprises: A switch device, wherein a first terminal of the switch device is coupled to the negative input terminal of the third differential amplifier unit through the feedback resistor, and a second terminal of the switch device is coupled to the negative input terminal of the fourth differential amplifier unit; A voltage-dividing filter component, wherein a first end of the voltage-dividing filter component is coupled to the control end of the switch device, a second end of the voltage-dividing filter component is grounded, and a third end of the voltage-dividing filter component is coupled to the processing module.
7. The temperature acquisition circuit according to claim 5, characterized in that: The second differential amplification module further includes: a third resistor, wherein a first end of the third resistor is coupled to the output end of the third differential amplifier unit, and a second end of the third resistor is coupled to the negative input end of the third differential amplifier unit; A fourth resistor, wherein a first end of the fourth resistor is coupled to the output end of the fourth differential amplifier unit, and a second end of the fourth resistor is coupled to the negative input end of the fourth differential amplifier unit.
8. The temperature acquisition circuit according to claim 1, characterized in that: The temperature acquisition circuit also includes: A common mode inductor, wherein a first input end of the common mode inductor is coupled to a first end of the target thermal resistor, and a second input end of the common mode inductor is coupled to a second end of the target thermal resistor; A first capacitor is connected in parallel to the first output terminal and the second output terminal of the common mode inductor and the first input terminal and the second input terminal of the first differential amplifier module.
9. The temperature acquisition circuit according to claim 1, characterized in that: The temperature acquisition circuit also includes: An input voltage providing module is connected in parallel to two ends of the target thermal resistor to provide the input voltage to the first differential amplification module.
10. A motor device, characterized in that: The motor device comprises the temperature acquisition circuit as described in any one of claims 1-9.