Overheat protection circuit and electronic equipment

Abstract

The utility model provides an overheating protection circuit and electronic equipment. The thermal protection circuit comprises a temperature detection module, a first parallel module and a second parallel module. The temperature detection module is respectively connected with the control end of the first parallel module and the control end of the second parallel module, the temperature detection module is respectively connected with the first parallel module and the second parallel module, the second parallel module is connected with a load in parallel, and the first parallel module is connected with a divider resistor connected with the load in series. The temperature detection module is used for detecting the temperature of the load, when the temperature of the load rises to a preset temperature threshold value, the temperature detection module is switched on and outputs an over-temperature signal, and the switching-on voltage drop of the temperature detection module is reduced along with the rise of the temperature of the load. The first parallel module is used for stopping working when receiving the over-temperature signal; and the second parallel module is used for working when receiving the over-temperature signal. In this way, the possibility that the load is damaged due to overheating can be reduced.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to an overheat protection circuit and electronic device. Background Technology

[0002] If a chip runs under a large current for an extended period, it can cause serious problems. As the current flows through the chip, heat is generated due to resistance, causing the junction temperature to rise continuously. However, there is an upper limit to the junction temperature a chip can withstand. Once this limit is exceeded, the properties of the internal semiconductor materials change, electron migration intensifies, circuit resistance increases, power consumption rises further, and even more heat is generated.

[0003] As the high temperature continues, the internal structure of the chip is gradually damaged and eventually easily burned out, leading to equipment failure and affecting its normal use. Therefore, over-temperature protection is extremely important for the stable operation of the chip. Utility Model Content

[0004] This application provides an overheat protection circuit and electronic device that can reduce the possibility of load damage due to overheating and extend the service life of the load.

[0005] In a first aspect, embodiments of this application provide an overheat protection circuit, comprising a temperature detection module, a first parallel module, and a second parallel module. The temperature detection module is connected to the control terminals of both the first and second parallel modules, and is also connected to both the first and second parallel modules. The second parallel module is connected in parallel with a load, and the first parallel module is connected in series with a voltage divider resistor connected to the load. The temperature detection module is used to detect the temperature of the load. When the temperature of the load rises to a preset temperature threshold, the temperature detection module is activated and outputs an overheat signal. The on-state voltage drop of the temperature detection module decreases as the temperature of the load rises. The first parallel module is used to stop operating upon receiving the overheat signal, and the second parallel module is used to operate upon receiving the overheat signal.

[0006] In some embodiments, the temperature detection module includes a voltage regulator unit and a temperature sensing unit. The voltage regulator unit is connected to the control terminal of the temperature sensing unit, and the temperature sensing unit is also connected to the control terminals of the first parallel module and the second parallel module, respectively. The voltage regulator unit is also used to connect to a power supply. The voltage regulator unit is used to regulate the power supply voltage to generate a regulated voltage; the temperature sensing unit is used to detect the temperature of the load. When the temperature of the load rises to a preset temperature threshold, the forward voltage drop of the temperature sensing unit decreases to less than or equal to the regulated voltage, and the temperature sensing unit turns on and outputs the over-temperature signal.

[0007] In some embodiments, the voltage regulator unit includes a resistor R1 and a Zener diode D1. The first end of the resistor R1 is connected to a power supply, the second end of the resistor R1 is connected to the negative terminal of the Zener diode D1 and the control terminal of the temperature sensing unit, and the positive terminal of the Zener diode D1 is grounded.

[0008] In some embodiments, the temperature sensing unit includes a switching transistor Q1, resistors R2, R3, and R4. The control terminal of the switching transistor Q1 is connected to the voltage regulation unit. The first terminal of the switching transistor Q1 is connected to the power supply through the resistor R2. The second terminal of the switching transistor Q1 is connected to the first terminal of the resistor R3. The second terminal of the resistor R3 is connected to the first terminal of the resistor R4, the control terminal of the first parallel module, and the control terminal of the second parallel module, respectively. The second terminal of the resistor R4 is grounded.

[0009] In some embodiments, the first parallel module includes a first switching unit and a first parallel unit. The control terminal of the first switching unit is connected to the temperature detection module, and the first switching unit is also connected to the control terminal of the first parallel unit. The first parallel unit is connected to a voltage divider resistor connected in series with the load. The first switching unit is configured to turn on and output a first level signal when it receives the over-temperature signal; the first parallel unit is configured to stop operating when it receives the first level signal.

[0010] In some embodiments, the first switching unit includes a switching transistor Q5 and a resistor R9. The control terminal of the switching transistor Q5 is connected to the temperature detection module through the resistor R9, the first terminal of the switching transistor Q5 is connected to the control terminal of the first parallel unit, and the second terminal of the switching transistor Q5 is grounded.

[0011] In some embodiments, the first parallel unit includes a switch Q4, a resistor R6, and a resistor R8. The control terminal of the switch Q4 is connected to the second terminal of the resistor R6 and the first switching unit, the first terminal of the switch Q4 is connected to the second terminal of the resistor R8, the first terminal of the resistor R6 is connected to the first terminal of the resistor R8, the power supply, and the first terminal of the voltage divider resistor, and the second terminal of the switch Q4 is connected to the second terminal of the voltage divider resistor.

[0012] In some embodiments, the second parallel module includes a second switching unit and a shunt unit. The control terminal of the second switching unit is connected to the temperature detection module. The second switching unit is also connected to the shunt unit and the second terminal of the load, respectively. The shunt unit is also connected to the first terminal of the load. The second switching unit is configured to turn on upon receiving the over-temperature signal; the shunt unit is configured to connect the second terminal of the load in parallel with the load when the second switching unit is turned on.

[0013] In some embodiments, the second switching unit includes a switching transistor Q2. The control terminal of the switching transistor Q2 is connected to the temperature detection module, the first terminal of the switching transistor Q2 is connected to the shunt unit, and the second terminal of the switching transistor Q2 is connected to the second terminal of the load and grounded.

[0014] Secondly, embodiments of this application provide an electronic device, which includes the overheat protection circuit described above.

[0015] Unlike existing technologies, this application provides an overheat protection circuit and electronic device. The overheat protection circuit includes a temperature detection module, a first parallel module, and a second parallel module. Specifically, the temperature detection module performs real-time temperature detection on the load. Its forward voltage drop decreases as the load temperature rises. When the load temperature reaches a preset temperature threshold, the temperature detection module turns on and outputs an over-temperature signal. The over-temperature signal is transmitted to the first parallel module, which stops working upon receiving the signal. Since it is connected in series with the load via a voltage divider resistor, stopping its operation changes the voltage across the voltage divider resistor, thereby reducing the voltage across the load. Simultaneously, the over-temperature signal is also transmitted to the second parallel module, causing it to start working. Because the second parallel module is connected in parallel with the load, it diverts some current during operation, reducing the current flowing through the load. Furthermore, when the load temperature drops below the preset temperature threshold, the temperature detection module returns to its initial state, stops outputting the over-temperature signal, the first parallel module resumes operation, the second parallel module stops working, and the load resumes normal operation. The overheat protection circuit and electronic equipment provided in this application embodiment reduce the power and heat generation of the load when it is overheated through the synergistic effect of the temperature detection module, the first parallel module and the second parallel module, thereby reducing the possibility of the load being damaged due to excessive temperature. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1This is a structural block diagram of the overheat protection circuit provided in the embodiments of this application;

[0018] Figure 2 This is a schematic diagram of the circuit structure of the overheat protection circuit provided in the embodiment of this application. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and thoroughly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0020] The technical features involved in the various embodiments of this application described below do not conflict with each other and can be combined with each other.

[0021] When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements between them.

[0022] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more.

[0023] Please see Figure 1 , Figure 1 This is a structural block diagram of the overheat protection circuit 100 provided in the embodiments of this application.

[0024] In a first aspect, embodiments of this application provide an overheat protection circuit 100, which includes a temperature detection module 10, a first parallel module 20, and a second parallel module 30.

[0025] The temperature detection module 10 is connected to the control terminal of the first parallel module 20 and the control terminal of the second parallel module 30, respectively. The temperature detection module 10 is connected to the first parallel module 20 and the second parallel module 30, respectively. The second parallel module 30 is connected in parallel with the load 200, and the first parallel module 20 is connected in series with the voltage divider resistor 300 of the load 200.

[0026] Specifically, the temperature detection module 10 is used to detect the temperature of the load 200. When the temperature of the load 200 rises to a preset temperature threshold, the temperature detection module 10 is turned on and outputs an over-temperature signal. The on-state voltage drop of the temperature detection module 10 decreases as the temperature of the load 200 rises. The first parallel module 20 is used to stop working when an over-temperature signal is received. The second parallel module 30 is used to operate when an over-temperature signal is received.

[0027] The preset temperature threshold is a pre-set temperature threshold that can be set based on the actual application scenario. It only needs to meet the requirement that the temperature of the load 200 is greater than the preset temperature threshold when the load 200 is over-temperature.

[0028] The over-temperature signal is a specific signal output by the temperature detection module 10 when it detects that the load temperature has risen to a preset temperature threshold. The most common form of the over-temperature signal is a voltage signal, which is set based on the actual application scenario.

[0029] In practical applications, when load 200 is operating normally, i.e., without overheating, its temperature does not reach the preset temperature threshold. At this time, the temperature detection module 10 monitors the temperature of load 200 in real time. Because the temperature of load 200 does not reach the preset temperature threshold, the forward voltage drop of the temperature detection module is relatively high, so the temperature detection module 10 is turned off and does not output an over-temperature signal. Simultaneously, the first parallel module 20 operates. Since it is connected in series with the voltage divider resistor 300 of load 200, its normal operation helps maintain the normal voltage division in the circuit containing the voltage divider resistor 300, thereby ensuring that load 200 can operate stably at a suitable voltage. Furthermore, the second parallel module 30 stops operating because it does not receive an over-temperature signal and therefore does not have any additional impact on the normal operation of load 200. Load 200 operates according to its normal operating mode, and current flows normally through load 200.

[0030] When load 200 overheats, its temperature rises to a preset temperature threshold. The on-state voltage drop of temperature detection module 10 decreases as the temperature of load 200 rises. When the preset temperature threshold is reached, temperature detection module 10 turns on and outputs an over-temperature signal. On one hand, the first parallel module 20 stops working after receiving the over-temperature signal. Since the first parallel module 20 is connected to the voltage divider resistor 300 in series with load 200, its cessation of operation changes the state of the circuit containing the voltage divider resistor 300, increasing the voltage across the voltage divider resistor 300, thereby reducing the voltage across load 200 and reducing the heat generated by load 200. On the other hand, the second parallel module 30 starts working after receiving the over-temperature signal. Since the second parallel module 30 is connected in parallel with load 200, its operation creates a new current branch in the circuit. According to the current splitting principle of parallel circuits, a portion of the current flows through the second parallel module 30, thereby reducing the current through load 200 and further reducing the heat generated by load 200. Thus, through the coordinated operation of the first parallel module 20 and the second parallel module 30, the power and heat generation of the load 200 are effectively reduced, providing overheat protection and reducing the possibility of damage to the load 200 due to excessive temperature. When the temperature of the load 200 drops below the preset temperature threshold, the temperature detection module 10 stops outputting the overtemperature signal, the first parallel module 20 resumes operation, the second parallel module 30 stops operation, and the load 200 returns to normal operation.

[0031] Please see Figure 2 , Figure 2 This is a schematic diagram of the circuit structure of the overheat protection circuit provided in the embodiment of this application.

[0032] In some embodiments, such as Figure 2 As shown, the temperature detection module 10 includes a voltage regulator unit 11 and a temperature sensing unit 12.

[0033] The voltage regulator unit 11 is connected to the control terminal of the temperature sensing unit 12. The temperature sensing unit 12 is also connected to the control terminal of the first parallel module 20 and the control terminal of the second parallel module 30. The voltage regulator unit 11 is also used to connect to the power supply VCC.

[0034] Specifically, the voltage regulator unit 11 is used to regulate the power supply voltage to generate a regulated voltage. The temperature sensing unit 12 is used to detect the temperature of the load 200. When the temperature of the load 200 rises to a preset temperature threshold, the on-state voltage drop of the temperature sensing unit 12 drops to less than or equal to the regulated voltage, and the temperature sensing unit 12 turns on and outputs an over-temperature signal.

[0035] like Figure 2 As shown, in some embodiments, the voltage regulator unit 11 includes a resistor R1 and a Zener diode D1.

[0036] Among them, the first end of resistor R1 is connected to power supply VCC, the second end of resistor R1 is connected to the negative terminal of Zener diode D1 and the control terminal of temperature sensing unit 12 respectively, and the positive terminal of Zener diode D1 is grounded.

[0037] In some embodiments, the temperature sensing unit 12 includes a switching transistor Q1, a resistor R2, a resistor R3, and a resistor R4.

[0038] The control terminal of the switching transistor Q1 is connected to the voltage regulator unit 11. The first terminal of the switching transistor Q1 is connected to the power supply VCC through the resistor R2. The second terminal of the switching transistor Q1 is connected to the first terminal of the resistor R3. The second terminal of the resistor R3 is connected to the first terminal of the resistor R4, the control terminal of the first parallel module 20, and the control terminal of the second parallel module 30, respectively. The second terminal of the resistor R4 is grounded.

[0039] During installation, the switching transistor Q1 is placed within a preset distance range from the load 200, allowing its on-state voltage drop to adjust based on the temperature changes of the load 200. Specifically, the on-state voltage drop of the switching transistor Q1 decreases as the temperature of the load 200 increases.

[0040] In practical applications, resistor R1 is connected to the power supply VCC to limit current, and the positive terminal of Zener diode D1 is grounded to regulate the power supply voltage output from VCC, generating a stable regulated voltage. Figure 2 The voltage at point V1 is transmitted to the control terminal of switch Q1. Switch Q1 detects the temperature of load 200. When the temperature of load 200 does not reach the preset temperature threshold, the on-state voltage drop of switch Q1 is large (greater than the regulated voltage), switch Q1 is in the off state, and the voltage at the connection point of resistors R3 and R4 (i.e., the voltage at point V1) is transmitted to the control terminal of switch Q1. Figure 2 The voltage at point V2 is close to 0V, so no over-temperature signal is output.

[0041] Subsequently, if the temperature of the load 200 rises to the preset temperature threshold, the on-state voltage drop of the switch Q1 decreases to less than or equal to the regulated voltage, causing it to turn on. Current is generated from the power supply VCC through resistor R2, switch Q1, resistor R3, and resistor R4 to ground, creating a high-level over-temperature signal at point V2. At this time, the voltage at point V2 is V2 = (V1 - VF) / (R3 + R4) * R4, where V2 is... Figure 2 The voltage at point V2, V1 is Figure 2 The voltage at point V1 is VF, which is the forward voltage drop of switch Q1. R3 and R4 are the resistance values ​​of resistors R3 and R4, respectively. The over-temperature signal is output to the control terminals of the first parallel module 20 and the second parallel module 30, triggering subsequent overheat protection actions.

[0042] In this embodiment, the switching transistor Q1 is an NPN transistor. The base of the NPN transistor is the control terminal of the switching transistor Q1, the collector of the NPN transistor is the first terminal of the switching transistor Q1, and the emitter of the NPN transistor is the second terminal of the switching transistor Q1.

[0043] In addition, the switching transistor Q1 can be any controllable switch, such as an insulated gate bipolar transistor (IGBT) device, an integrated gate commutated thyristor (IGCT) device, a gate turn-off thyristor (GTO) device, a silicon controlled rectifier (SCR) device, a junction gate field-effect transistor (JFET) device, a MOS controlled thyristor (MCT) device, etc.

[0044] In some embodiments, such as Figure 2 As shown, the first parallel module 20 includes a first switching unit 21 and a first parallel unit 22.

[0045] The control terminal of the first switching unit 21 is connected to the temperature detection module 10. The first switching unit 21 is also connected to the control terminal of the first parallel unit 22. The first parallel unit 22 is connected to the voltage divider resistor 300 connected in series with the load 200.

[0046] Specifically, the first switching unit 21 is used to turn on and output a first level signal when an over-temperature signal is received. The first parallel unit 22 is used to stop working when the first level signal is received.

[0047] like Figure 2 As shown, in some embodiments, the first switching unit 21 includes a switching transistor Q5 and a resistor R9.

[0048] The control terminal of the switching transistor Q5 is connected to the temperature detection module 10 through resistor R9, the first terminal of the switching transistor Q5 is connected to the control terminal of the first parallel unit 22, and the second terminal of the switching transistor Q5 is grounded.

[0049] In some embodiments, the first parallel unit 22 includes a switch Q4, a resistor R6, and a resistor R8.

[0050] The control terminal of the switching transistor Q4 is connected to the second terminal of the resistor R6 and the first switching unit 21, the first terminal of the switching transistor Q4 is connected to the second terminal of the resistor R8, the first terminal of the resistor R6 is connected to the first terminal of the resistor R8, the power supply VCC and the first terminal of the voltage divider resistor 300, and the second terminal of the switching transistor Q4 is connected to the second terminal of the voltage divider resistor 300.

[0051] In practical applications, when the temperature detection module 10 does not output an over-temperature signal, the control terminal of the switching transistor Q5 in the first switching unit 21 has no valid signal, and the switching transistor Q5 is turned off. In the first parallel unit 22, the control terminal of the switching transistor Q4 obtains a suitable level from the power supply VCC through the resistor R6 and is turned on. At this time, the first parallel unit 22 works normally, and the resistor R8 is connected in parallel with the voltage divider resistor 300 to maintain the normal operation of the load 200.

[0052] Subsequently, when the temperature detection module 10 detects that the temperature of the load 200 has reached the preset threshold and outputs an over-temperature signal, the over-temperature signal is transmitted to the control terminal of the switching transistor Q5 through resistor R9, causing the switching transistor Q5 to conduct. The first terminal of the switching transistor Q5 outputs a first-level signal (low-level signal) to the control terminal of the first parallel unit switching transistor Q4, causing the switching transistor Q4 to turn off, and the first parallel unit 22 stops working. At this time, resistor R8 is not connected in parallel with the voltage divider resistor 300, thereby reducing the voltage across the load 200 and achieving overheat protection.

[0053] In this embodiment, taking NPN transistors Q4 and Q5 as examples, the base of switch Q4 is the control terminal, the collector is the first terminal, and the emitter is the second terminal. Similarly, the base of switch Q5 is the control terminal, the collector is the first terminal, and the emitter is the second terminal.

[0054] In addition, switching transistors Q4 and Q5 can be any controllable switch, such as insulated gate bipolar transistor (IGBT) devices, integrated gate commutated thyristor (IGCT) devices, gate turn-off thyristor (GTO) devices, silicon controlled rectifier (SCR) devices, junction gate field-effect transistor (JFET) devices, MOS controlled thyristor (MCT) devices, etc.

[0055] In some embodiments, such as Figure 2 As shown, the second parallel module 30 includes a second switching unit 31 and a current shunting unit 32.

[0056] The control terminal of the second switching unit 31 is connected to the temperature detection module 10. The second switching unit 31 is also connected to the shunt unit 32 and the second end of the load 200, respectively. The shunt unit 32 is also connected to the first end of the load 200.

[0057] Specifically, the second switching unit 31 is used to turn on when an over-temperature signal is received. The shunt unit 32 is used to connect the second terminal of the load 200 through the second switching unit 31 when the second switching unit 31 is turned on, so as to connect in parallel with the load 200.

[0058] like Figure 2 As shown, in some embodiments, the second switching unit 31 includes a switching transistor Q2.

[0059] Among them, the control terminal of the switching transistor Q2 is connected to the temperature detection module 10, the first terminal of the switching transistor Q2 is connected to the shunt unit 32, and the second terminal of the switching transistor Q2 is connected to the second terminal of the load 200 and grounded.

[0060] In some embodiments, the shunt unit 32 includes a resistor R7.

[0061] Among them, the first end of resistor R7 is connected to the first end of load 200, and the second end of resistor R7 is connected to the second switch unit 31.

[0062] In practical applications, when the temperature detection module 10 does not output an over-temperature signal, the control terminal of the switch Q2 in the second switch unit 31 has no trigger signal, the switch Q2 is in the off state, and the resistor R7 in the shunt unit 32 is not connected to the second terminal of the load 200, that is, the resistor R7 is not connected in parallel with the load 200, so as to maintain the normal working state of the load 200.

[0063] Subsequently, when the temperature detection module 10 detects that the temperature of the load 200 has reached the preset temperature threshold and outputs an over-temperature signal, the over-temperature signal is transmitted to the control terminal of the switching transistor Q2, causing the switching transistor Q2 to conduct. At this time, the resistor R7 of the shunt unit 32 is connected to the second terminal of the load 200 through the conducting switching transistor Q2. The resistor R7 is connected in parallel with the load 200, thereby changing the current distribution in the circuit and playing a role in regulating and protecting the circuit when the load 200 overheats, thereby reducing the heat generated by the load 200.

[0064] In this embodiment, the switching transistor Q2 is an NPN transistor. The base of the NPN transistor is the control terminal of the switching transistor Q2, the collector of the NPN transistor is the first terminal of the switching transistor Q2, and the emitter of the NPN transistor is the second terminal of the switching transistor Q2.

[0065] In addition, the switching transistor Q2 can be any controllable switch, such as an insulated gate bipolar transistor (IGBT) device, an integrated gate commutated thyristor (IGCT) device, a gate turn-off thyristor (GTO) device, a silicon controlled rectifier (SCR) device, a junction gate field-effect transistor (JFET) device, a MOS controlled thyristor (MCT) device, etc.

[0066] In summary, Figure 2In the illustrated embodiment, overheat detection is achieved through switch Q1. When the load 200 overheats, the linkage between switches Q5 and Q4 disconnects resistor R8, increasing the voltage drop across the voltage divider resistor 300 and thus reducing the voltage across the load 200, thereby reducing heat generation. Simultaneously, the conduction of switch Q2 connects resistor R7 in parallel with the load 300, shunting the current and further reducing the current in the load 200, thus further reducing heat generation. Furthermore, the entire system is implemented using hardware circuitry, which offers a faster response time compared to related technologies that use controller output signals, enabling rapid overheat protection.

[0067] Secondly, embodiments of this application provide an electronic device, which includes the overheat protection circuit 100 as described above.

[0068] The specific structure and working principle of the overheat protection circuit 100 can be referred to the above embodiments, and will not be repeated here.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, and there are many other variations of different aspects of this utility model as described above. For the sake of brevity, they are not provided in detail; although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. An overheat protection circuit, characterized in that, The overheat protection circuit includes a temperature detection module, a first parallel module, and a second parallel module; The temperature detection module is connected to the control terminal of the first parallel module and the control terminal of the second parallel module respectively. The temperature detection module is connected to the first parallel module and the second parallel module respectively. The second parallel module is connected in parallel with the load. The first parallel module is connected to the voltage divider resistor connected in series with the load. The temperature detection module is used to detect the temperature of the load. When the temperature of the load rises to a preset temperature threshold, the temperature detection module is turned on and outputs an over-temperature signal. The on-state voltage drop of the temperature detection module decreases as the temperature of the load rises. The first parallel module is used to stop working when the over-temperature signal is received; the second parallel module is used to work when the over-temperature signal is received.

2. The overheat protection circuit according to claim 1, characterized in that, The temperature detection module includes a voltage regulator unit and a temperature sensing unit; The voltage regulator unit is connected to the control terminal of the temperature sensing unit, and the temperature sensing unit is also connected to the control terminals of the first parallel module and the second parallel module respectively. The voltage regulator unit is also used to connect to the power supply. The voltage regulator unit is used to regulate the power supply voltage to generate a regulated voltage; The temperature sensing unit is used to detect the temperature of the load. When the temperature of the load rises to a preset temperature threshold, the on-state voltage drop of the temperature sensing unit drops to less than or equal to the regulated voltage, and the temperature sensing unit turns on and outputs the over-temperature signal.

3. The overheat protection circuit according to claim 2, characterized in that, The voltage regulator unit includes a resistor R1 and a Zener diode D1; The first end of the resistor R1 is connected to the power supply, the second end of the resistor R1 is connected to the negative terminal of the Zener diode D1 and the control terminal of the temperature sensing unit, and the positive terminal of the Zener diode D1 is grounded.

4. The overheat protection circuit according to claim 2, characterized in that, The temperature sensing unit includes a switching transistor Q1, a resistor R2, a resistor R3, and a resistor R4; The control terminal of the switching transistor Q1 is connected to the voltage regulator unit. The first terminal of the switching transistor Q1 is connected to the power supply through the resistor R2. The second terminal of the switching transistor Q1 is connected to the first terminal of the resistor R3. The second terminal of the resistor R3 is connected to the first terminal of the resistor R4, the control terminal of the first parallel module, and the control terminal of the second parallel module, respectively. The second terminal of the resistor R4 is grounded.

5. The overheat protection circuit according to claim 1, characterized in that, The first parallel module includes a first switching unit and a first parallel unit; The control terminal of the first switching unit is connected to the temperature detection module. The first switching unit is also connected to the control terminal of the first parallel unit. The first parallel unit is connected to the voltage divider resistor connected in series with the load. The first switching unit is configured to turn on and output a first level signal when the over-temperature signal is received; The first parallel unit is used to stop working when it receives the first level signal.

6. The overheat protection circuit according to claim 5, characterized in that, The first switching unit includes a switching transistor Q5 and a resistor R9; The control terminal of the switch Q5 is connected to the temperature detection module through the resistor R9. The first terminal of the switch Q5 is connected to the control terminal of the first parallel unit, and the second terminal of the switch Q5 is grounded.

7. The overheat protection circuit according to claim 5, characterized in that, The first parallel unit includes a switch Q4, a resistor R6, and a resistor R8; The control terminal of the switching transistor Q4 is connected to the second terminal of the resistor R6 and the first switching unit, respectively. The first terminal of the switching transistor Q4 is connected to the second terminal of the resistor R8. The first terminal of the resistor R6 is connected to the first terminal of the resistor R8, the power supply and the first terminal of the voltage divider resistor, respectively. The second terminal of the switching transistor Q4 is connected to the second terminal of the voltage divider resistor.

8. The overheat protection circuit according to claim 1, characterized in that, The second parallel module includes a second switching unit and a current shunt unit; The control terminal of the second switching unit is connected to the temperature detection module. The second switching unit is also connected to the second terminal of the shunt unit and the load, respectively. The shunt unit is also connected to the first terminal of the load. The second switching unit is used to turn on when the over-temperature signal is received; The shunt unit is used to connect the second end of the load to the load in parallel when the second switching unit is turned on.

9. The overheat protection circuit according to claim 8, characterized in that, The second switching unit includes a switching transistor Q2; The control terminal of the switching transistor Q2 is connected to the temperature detection module, the first terminal of the switching transistor Q2 is connected to the shunt unit, and the second terminal of the switching transistor Q2 is connected to the second terminal of the load and grounded.

10. An electronic device, characterized in that, The electronic device includes an overheat protection circuit as described in any one of claims 1 to 9.

Images