A temperature protection device for a switching tube and an electrical equipment

Abstract

The present invention discloses a temperature protection device and an electrical equipment for a switching tube. The device includes: a switching tube body, a temperature detection unit, and a temperature protection unit; the switching tube body and the temperature detection unit are integrally arranged; the temperature protection unit is respectively connected to the temperature detection unit and the switching tube body; wherein, the temperature detection unit is configured to detect the temperature of the switching tube body, and output a temperature protection signal when the temperature of the switching tube body is greater than or equal to the temperature protection threshold of the switching tube body; the temperature protection unit is configured to turn off the drive signal of the switching tube body when receiving the temperature protection signal, so as to realize the temperature protection of the switching tube body. This solution improves the reliability of the temperature protection of the switching tube by improving the accuracy of the temperature detection of the switching tube.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic circuits, and particularly relates to a temperature protection device for a switching tube and an electrical device, and more particularly to a switching tube with temperature protection and an electrical device having the switching tube. Background Art

[0002] In the temperature protection scheme of a switching tube, it is necessary to detect the temperature of the switching tube through a temperature sensing element. The temperature sensing element is arranged outside the switching tube and is affected by the external environment of the switching tube. The detected temperature is often not the true temperature of the temperature sensing element, which affects the accuracy of the temperature detection of the temperature sensing element and also affects the reliability of the temperature protection of the switching tube.

[0003] The above content is only used to assist in understanding the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The object of the present invention is to provide a temperature protection device for a switching tube and an electrical device, so as to solve the problem that the reliability of the temperature protection of the switching tube is affected due to the insufficient accuracy of the temperature detection of the switching tube by using a temperature sensing element arranged outside the switching tube, and achieve the effect of improving the reliability of the temperature protection of the switching tube by improving the accuracy of the temperature detection of the switching tube.

[0005] The present invention provides a temperature protection device for a switching tube, including: a switching tube body, a temperature detection unit, and a temperature protection unit; the switching tube body and the temperature detection unit are integrally arranged; the temperature protection unit is respectively connected to the temperature detection unit and the switching tube body; wherein, the temperature detection unit is configured to detect the temperature of the switching tube body, and output a temperature protection signal when the temperature of the switching tube body is greater than or equal to the temperature protection threshold of the switching tube body; the temperature protection unit is configured to turn off the drive signal of the switching tube body when receiving the temperature protection signal, so as to realize the temperature protection of the switching tube body.

[0006] In some embodiments, the temperature detection unit includes: a temperature-sensitive unit and a pull-down unit; wherein, the temperature-sensitive unit, the pull-down unit, and the switching tube body are integrally arranged; after the temperature-sensitive unit and the pull-down unit are connected, they are arranged between the drive end and the output end of the switching tube body.

[0007] In some embodiments, the temperature-sensitive unit includes a thermistor; the pull-down unit includes a triode; the switch transistor body includes a MOS transistor; wherein, after the thermistor and the triode are connected, they are connected in parallel between the gate and the source of the MOS transistor; the triode is further connected to the temperature protection unit; wherein, the first end of the thermistor is connected to the base and the collector of the triode, and the second end of the thermistor is connected to the emitter of the triode.

[0008] In some embodiments, the temperature detection unit further includes a capacitor unit; wherein, the temperature-sensitive unit, the pull-down unit, the capacitor unit and the switch transistor body are integrally arranged; the capacitor unit is arranged between the driving end and the output end of the switch transistor body.

[0009] In some embodiments, the capacitor unit includes a capacitor; the capacitor is connected in parallel with the series connection of the temperature-sensitive unit and the pull-down unit, and the capacitor is located between the temperature-sensitive unit and the switch transistor body.

[0010] In some embodiments, the temperature-sensitive unit, the pull-down unit, the capacitor unit and the switch transistor body are integrally packaged into an integrated structure.

[0011] In some embodiments, the temperature protection unit includes a driving chip and a driving resistor; wherein, the first end of the driving chip is connected to the driving end of the switch transistor body through the driving resistor; the second end of the driving chip is connected to the output end of the switch transistor body; when the temperature-sensitive unit detects that the temperature of the switch transistor body is greater than or equal to the temperature protection threshold of the switch transistor body, the pull-down unit pulls down the output signal of the driving chip to 0, so that the driving signal of the switch transistor body is turned off.

[0012] Matched with the above device, on the other hand, the present invention provides an electrical device, including the temperature protection device of the switch transistor described above.

[0013] Thus, in the solution of the present invention, by arranging the thermistor and the pull-down unit inside the switch transistor, the temperature of the switch transistor is detected by using the thermistor, and when the temperature of the switch transistor detected by the thermistor reaches the temperature protection threshold of the switch transistor, the driving signal of the switch transistor is pulled low by the pull-down unit to turn off the switch transistor, so as to realize the temperature protection of the switch transistor. Therefore, by improving the accuracy of the temperature detection of the switch transistor, the reliability of the temperature protection of the switch transistor is improved.

[0014] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. is a schematic structural diagram of an embodiment of the temperature protection device for a switching tube of the present invention;

[0017] Figure 2 FIG. is a schematic structural diagram of an embodiment of a switching tube temperature protection circuit;

[0018] Figure 3 FIG. is a schematic structural diagram of another embodiment of a switching tube temperature protection circuit;

[0019] Figure 4 FIG. is a specific structural diagram of another embodiment of a switching tube temperature protection circuit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] According to an embodiment of the present invention, a temperature protection device for a switching tube is provided. Refer to Figure 1 FIG. which is a schematic structural diagram of an embodiment of the device of the present invention. The temperature protection device for the switching tube may include: a switching tube body (such as switching tube body M1), a temperature detection unit (such as thermistor R2 and triode Q1), and a temperature protection unit (such as a drive chip and drive resistor R1). The switching tube body and the temperature detection unit are integrally provided to form Figure 3 and Figure 4 the switching tube M shown in FIG. The temperature protection unit is respectively connected to the temperature detection unit and the switching tube body.

[0022] Among them, the temperature detection unit is configured to detect the temperature of the switching tube body and output a temperature protection signal when the temperature of the switching tube body is greater than or equal to the temperature protection threshold of the switching tube body.

[0023] In some embodiments, the temperature detection unit includes: a temperature-sensitive unit and a pull-down unit.

[0024] Among them, the temperature-sensitive unit, the pull-down unit, and the switch tube body are integrally arranged. After the temperature-sensitive unit and the pull-down unit are connected, they are arranged between the driving end (such as the gate G of the switch tube body M1) and the output end (such as the source S of the switch tube body) of the switch tube body.

[0025] Thus, by directly integrating the temperature-sensitive resistor R2 into the switch tube M, the sampling of the temperature-sensitive resistor R2 is accurate, and once the voltage of the pull-down unit (such as the triode Q1) drops to a certain value, the driving signal of the switch tube M is immediately reduced to 0, with a fast response speed, improving the temperature detection accuracy and temperature protection sensitivity of the switch tube temperature protection circuit, and also reducing the design difficulty of the switch tube temperature protection circuit.

[0026] In some embodiments, the temperature-sensitive unit includes a temperature-sensitive resistor (such as the temperature-sensitive resistor R2). The pull-down unit includes a triode (such as the triode Q1). The switch tube body includes a MOS tube.

[0027] Among them, after the temperature-sensitive resistor and the triode are connected, they are connected in parallel between the gate and the source of the MOS tube; among them, the first end of the temperature-sensitive resistor is connected to the base and the collector of the triode, and the second end of the temperature-sensitive resistor is connected to the emitter of the triode. The triode is also connected to the temperature protection unit.

[0028] Thus, by integrating and packaging the temperature-sensitive resistor R2 and the switch tube M into an integrated unit, that is, integrating the temperature-sensitive resistor R2 and the switch tube body M1 to obtain the switch tube M, the problem of poor accuracy of external temperature sensing package temperature sampling is solved, and the problem of switch tube explosion caused by inaccurate sampling due to too high switch tube temperature is reduced or even avoided.

[0029] In some embodiments, the temperature detection unit further includes a capacitor unit (such as the capacitor C2).

[0030] Among them, the temperature-sensitive unit, the pull-down unit, the capacitor unit, and the switch tube body are integrally arranged. The capacitor unit is arranged between the driving end (such as the gate G of the switch tube body M1) and the output end (such as the source S of the switch tube body) of the switch tube body.

[0031] In some embodiments, the capacitor unit includes a capacitor (such as the capacitor C2). After the capacitor, the temperature-sensitive unit, and the pull-down unit are connected in series, they are connected in parallel with the capacitor, and the capacitor is located between the temperature-sensitive unit and the switch tube body.

[0032] In some embodiments, the temperature-sensitive unit, the pull-down unit, the capacitor unit, and the switch tube body are integrally packaged into an integrated structure.

[0033] Thus, by integrating the temperature-sensitive resistor R2 and the switching transistor M in a single package, the problems of complex structure and high cost of the precise temperature sampling circuit are solved, the structure is simplified, the cost is reduced, and it is easy to design and implement.

[0034] The temperature protection unit is configured to turn off the driving signal of the switching transistor body upon receiving the temperature protection signal, so as to achieve temperature protection for the switching transistor body.

[0035] Thus, by integrating a temperature detection unit such as a temperature detection circuit within the switching transistor M, the temperature detection is highly accurate, and the reliability of temperature protection is high. By directly reducing the drive to 0 through the temperature detection circuit, the response speed is fast. Moreover, the structure of the temperature protection circuit is simple and does not require complex control by an MCU.

[0036] In some embodiments, the temperature protection unit includes: a driving chip and a driving resistor (such as driving resistor R1).

[0037] Wherein, the first end of the driving chip is connected to the driving end of the switching transistor body via the driving resistor. The second end of the driving chip is connected to the output end of the switching transistor body. When the temperature sensing unit detects that the temperature of the switching transistor body is greater than or equal to the temperature protection threshold of the switching transistor body, the pull-down unit pulls down the output signal of the driving chip to 0, so that the driving signal of the switching transistor body is turned off.

[0038] Specifically, the driving chip (such as driving IC) sends a driving signal to the driving pole, i.e., the gate G, of the switching transistor M according to the output voltage of the switching transistor M. The driving resistor R1 can limit the output current of the driving chip. The resistance value of the temperature-sensitive resistor R2 increases with the increase of temperature, and the higher the temperature, the smaller the resistance value. The pull-down unit (such as the triode Q1) pulls down the voltage across both ends of the capacitor C2 (i.e., between the gate G and the source S of the switching transistor body M1) to 0 when the supply voltage decreases to a certain value.

[0039] When the temperature of the switching transistor M increases, the resistance value of the temperature-sensitive resistor R2 increases. The temperature-sensitive resistor R2, the pull-down unit (such as the triode Q1), and the capacitor C2 (i.e., the gate G and the source S of the switching transistor body M1) form a loop, and the current in the loop decreases. The voltage across the temperature-sensitive resistor R2 decreases. According to the KVL law (i.e., Kirchhoff's voltage law), the voltage of the pull-down unit (such as the triode Q1) drops. When the temperature of the temperature-sensitive resistor R2 increases to the temperature protection value of the switching transistor M, the pull-down unit (such as the triode Q1) will pull down the output signal of the driving IC to 0, and the driving signal of the switching transistor M is 0, and the switching transistor body M1 (such as a MOS transistor) in the switching transistor M stops working. In this way, the solution of the present invention integrates the temperature detection circuit into the switching transistor M, and the temperature detection accuracy is good. The driving is directly reduced to 0 through the detection circuit, and the response speed is fast. Moreover, the structure of the temperature protection circuit is simple and does not require complex control by the MCU.

[0040] After a large number of experimental verifications, by adopting the technical solution of the present invention, the temperature-sensitive resistor and the pull-down unit are arranged inside the switching transistor to detect the temperature of the switching transistor by using the temperature-sensitive resistor, and when the temperature of the switching transistor detected by the temperature-sensitive resistor reaches the temperature protection threshold of the switching transistor, the driving signal of the switching transistor is pulled low through the pull-down unit to turn off the switching transistor, so as to realize the temperature protection of the switching transistor. Thus, by improving the accuracy of the temperature detection of the switching transistor, the reliability of the temperature protection of the switching transistor is improved.

[0041] According to an embodiment of the present invention, there is also provided an electrical device corresponding to the temperature protection device of the switching transistor. The electrical device may include: the temperature protection device of the switching transistor described above.

[0042] Figure 2 It is a schematic structural diagram of an embodiment of a temperature protection circuit for a switching transistor. As Figure 2 shown, the temperature protection circuit for the switching transistor includes: a switching transistor M, a temperature sensing package, a temperature detection circuit, an MCU, a driving resistor R1, and a driving chip (i.e., a driving IC). In the switching transistor M, a capacitor C1 is provided. The capacitor C1 is connected between the gate G and the source S of the switching transistor M. The temperature sensing package is arranged outside the switching transistor M and is in contact with the source S of the switching transistor M. The temperature sensing package, the temperature detection circuit, the MCU, and the driving IC are connected in sequence. One end of the driving IC is connected to the gate G of the switching transistor M through the driving resistor R1. The other end of the driving IC is connected to the source S of the switching transistor M.

[0043] In Figure 2 the example shown, when the temperature of the switching transistor M is too high, the temperature of the temperature sensing package is detected and the temperature signal is transmitted to the MCU, and the MCU stops sending the driving signal to the driving chip, and the switching transistor M such as a MOS transistor stops working.

[0044] In Figure 2In the shown switching transistor temperature protection circuit, the switching transistor has the disadvantage of low temperature protection sensitivity (generally remaining at the order of dozens of microvolts per degree Celsius). Therefore, in the actual design and use of the switching transistor temperature protection circuit, engineers often need a low-offset amplifier to generate an available output voltage. Within the operating range of the switching transistor temperature protection circuit, the nonlinearity in the temperature-to-voltage transfer function often requires a compensation circuit or a look-up table, resulting in a complex circuit and a relatively long response time.

[0045] Figure 3 It is a schematic structural diagram of another embodiment of a switching transistor temperature protection circuit. Figure 4 It is a specific schematic structural diagram of another embodiment of a switching transistor temperature protection circuit. As Figure 3 and Figure 4 shown, the switching transistor temperature protection circuit includes: a switching transistor M, a driving resistor R1, and a driving chip (such as a driving IC). In the switching transistor M, there are provided a switching transistor body M1, a capacitor C2, a thermistor R2, and a triode Q1. The capacitor C2 is connected between the gate G and the source S of the switching transistor body M1. After the thermistor R2 and the triode Q1 are connected, they are connected in parallel with the capacitor C2. The first end of the thermistor R2 is connected to the base of the triode Q1, the collector of the triode Q1, and the gate G of the switching transistor body M1, and the second end of the thermistor R2 is connected to the emitter of the triode Q1 and the source S of the switching transistor body M1. One end of the driving chip is connected to the gate G of the switching transistor body M1 after passing through the driving resistor R1. The other end of the driving chip is connected to the source S of the switching transistor body M1.

[0046] In Figure 3 and Figure 4 the shown example, the driving chip (such as a driving IC) sends a driving signal to the driving electrode, i.e., the gate G, of the switching transistor M according to the output voltage of the switching transistor M. The driving resistor R1 can limit the output current of the driving chip. The resistance value of the thermistor R2 decreases as the temperature increases, and the higher the temperature, the smaller the resistance value. The pull-down unit (such as the triode Q1) pulls down the voltage across the capacitor C2 (i.e., between the gate G and the source S of the switching transistor body M1) to 0 when the supply voltage decreases to a certain value.

[0047] When the temperature of the switching transistor M rises, the resistance value of the temperature-sensitive resistor R2 increases. The temperature-sensitive resistor R2, the pull-down unit (such as the triode Q1), and the capacitor C2 (i.e., the gate G and the source S of the switching transistor body M1) form a loop, and the current in the loop decreases. The voltage across the temperature-sensitive resistor R2 decreases. According to the KVL law (i.e., Kirchhoff's voltage law), the voltage of the pull-down unit (such as the triode Q1) drops. When the temperature of the temperature-sensitive resistor R2 increases to the temperature protection value of the switching transistor M, the pull-down unit (such as the triode Q1) will pull down the output signal of the driving IC to 0, and the driving signal of the switching transistor M is 0, and the switching transistor body M1 (such as a MOS transistor) in the switching transistor M stops working. In this way, the solution of the present invention integrates the temperature detection circuit into the switching transistor M, with good temperature detection accuracy; directly reduces the driving to 0 through the detection circuit, with a fast response speed; and moreover, the structure of the temperature protection circuit is simple and does not require complex control by an MCU.

[0048] In Figure 3 and Figure 4 In the example shown, the solution of the present invention directly integrates the temperature-sensitive resistor R2 into the switching transistor M, making the sampling of the temperature-sensitive resistor R2 accurate. And once the voltage of the pull-down unit (such as the triode Q1) drops to a certain value, it immediately reduces the driving signal of the switching transistor M to 0, with a fast response speed, improving the temperature detection accuracy and temperature protection sensitivity of the switching transistor temperature protection circuit, and also reducing the design difficulty of the switching transistor temperature protection circuit.

[0049] Figure 2 In the example shown, the temperature detection accuracy of the temperature sensing bulb for the switching transistor M is not high. Through Figure 3 and Figure 4 In the example shown, the improvement of temperature detection accuracy can be achieved. Specifically, the solution of the present invention integrates and packages the temperature-sensitive resistor R2 and the switching transistor M into one body, that is, the temperature-sensitive resistor R2 and the switching transistor body M1 are integrally arranged to obtain the switching transistor M, solving the problem of poor accuracy of external temperature sensing bulb temperature sampling, and reducing or even avoiding the problem of switching transistor explosion caused by inaccurate sampling due to too high temperature of the switching transistor.

[0050] In related solutions, the temperature detection circuit with high detection accuracy uses sampling circuits such as operational amplifiers and temperature sensing bulbs, with a complex structure and high cost. While the solution of the present invention integrates and packages the temperature-sensitive resistor R2 and the switching transistor M into one body, solving the problems of complex structure and high cost of the accurate temperature sampling circuit, simplifying the structure, reducing the cost, and being easy to design and implement.

[0051] Since the processing and functions implemented by the electrical equipment in this embodiment are basically corresponding to the embodiments, principles, and examples of the device shown in the foregoing Figure 1 For the parts not described in detail in the description of this embodiment, reference can be made to the relevant descriptions in the foregoing embodiments and will not be elaborated here.

[0052] After a large number of experimental verifications, by adopting the technical solution of the present invention, the temperature-sensitive resistor and the pull-down unit are arranged inside the switching tube, so as to detect the temperature of the switching tube by using the temperature-sensitive resistor, and when the temperature of the switching tube detected by the temperature-sensitive resistor reaches the temperature protection threshold of the switching tube, the drive signal of the switching tube is pulled low by the pull-down unit to turn off the switching tube, thereby realizing the temperature protection of the switching tube, solving the problem of poor accuracy of the external temperature sensing package for temperature sampling, reducing or even avoiding the problem of the switching tube exploding caused by inaccurate sampling due to the too high temperature of the switching tube, and improving the temperature detection accuracy and temperature protection sensitivity of the temperature protection circuit of the switching tube.

[0053] In summary, it is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0054] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A temperature protection device for a switching tube, characterized in that, Comprising: A switching transistor body, a temperature detection unit, and a temperature protection unit; the switching transistor body and the temperature detection unit are integrally provided; the temperature protection unit is respectively connected to the temperature detection unit and the switching transistor body; wherein, The temperature detection unit is configured to detect the temperature of the switching transistor body, and output a temperature protection signal when the temperature of the switching transistor body is greater than or equal to the temperature protection threshold of the switching transistor body; The temperature protection unit is configured to turn off the drive signal of the switching transistor body when receiving the temperature protection signal, so as to achieve temperature protection of the switching transistor body; The temperature detection unit includes: a temperature-sensitive unit and a pull-down unit; wherein, the temperature-sensitive unit, the pull-down unit, and the switching transistor body are integrally provided; after the temperature-sensitive unit and the pull-down unit are connected, they are arranged between the drive end and the output end of the switching transistor body; The temperature-sensitive unit includes: a temperature-sensitive resistor; the pull-down unit includes: a triode; the switching transistor body includes: a MOS transistor; wherein, after the temperature-sensitive resistor and the triode are connected, they are connected in parallel between the gate and the source of the MOS transistor; the triode is also connected to the temperature protection unit; wherein, the first end of the temperature-sensitive resistor is connected to the base and the collector of the triode, and the second end of the temperature-sensitive resistor is connected to the emitter of the triode; The temperature detection unit further includes: a capacitor unit; wherein, the temperature-sensitive unit, the pull-down unit, the capacitor unit, and the switching transistor body are integrally provided; the capacitor unit is arranged between the drive end and the output end of the switching transistor body; The capacitor unit includes: a capacitor; the capacitor is connected in parallel with the series connection of the temperature-sensitive unit and the pull-down unit, and the capacitor is located between the temperature-sensitive unit and the switching transistor body.

2. The temperature protection device for a switching tube according to claim 1, characterized in that, The temperature-sensitive unit, the pull-down unit, the capacitor unit, and the switching transistor body are integrally packaged into an integrated structure.

3. The temperature protection device for a switching tube according to claim 1, characterized in that, The temperature protection unit includes: a drive chip and a drive resistor; wherein, The first end of the drive chip is connected to the drive end of the switching transistor body through the drive resistor; the second end of the drive chip is connected to the output end of the switching transistor body; When the temperature-sensitive unit detects that the temperature of the switching transistor body is greater than or equal to the temperature protection threshold of the switching transistor body, the pull-down unit pulls down the output signal of the drive chip to 0, so that the drive signal of the switching transistor body is turned off.

4. An electrical equipment, characterized in that, Comprising: The temperature protection device for a switching transistor according to any one of claims 1 to 3.

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