Circuit for reducing temperature rise and air conditioner

Abstract

The present application relates to the technical field of overvoltage protection, in particular to a circuit for reducing temperature rise, a voltage reduction circuit and an air conditioner. The present application solves the problem of excessive temperature rise of a voltage stabilizing block in a circuit. To solve the above problem, the present application provides a circuit for reducing temperature rise, which comprises: an input module for inputting current to the circuit; a protection module electrically connected to the output module; an output module electrically connected to the protection module; and a voltage stabilizing block connected to the output module and the input module. At least part of the current passes through the protection module and then the voltage stabilizing block, and the remaining part of the current directly passes through the voltage stabilizing block.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of overvoltage protection, in particular to a circuit for reducing temperature rise, a voltage reduction circuit and an air conditioner. BACKGROUND

[0002] With the development of air conditioning technology, electronic devices are more and more precise, and the circuit board is shrinking, and the components are more closely packed, resulting in poor heat dissipation of some heat generating devices, excessive temperature rise, and test failure, affecting the service life of the device itself, and thus bringing problems such as high after-sales failure rate. One of the cores of the air conditioner circuit is the power supply circuit, which is also the part of the temperature rise problem that is focused on. In the related art, a voltage stabilizing block is usually used for voltage reduction, but because the voltage stabilizing block has a high temperature rise when passing a large current, a heat dissipation device is needed to spread heat outward to improve the heat dissipation conditions and thus reduce the temperature rise of the voltage stabilizing block itself, making the overall circuit not simple enough. SUMMARY

[0003] The present application solves the problem of excessive temperature rise of the voltage stabilizing block in the circuit.

[0004] To solve the above problems, the present application provides a circuit for reducing temperature rise, which comprises: an input module, the input module inputs current to the circuit; a protection module, the protection module is electrically connected with the output module; an output module, the output module is electrically connected with the protection module; and a voltage stabilizing block, the voltage stabilizing block is connected with the output module and the input module respectively; wherein the circuit is applied to a switching power supply, the input module stabilizes the input voltage, the current generated by the stabilized voltage passes through the voltage stabilizing block, part of the protection module is connected in parallel with the voltage stabilizing block, most of the current enters the protection module at this time, reducing the current size when the voltage stabilizing block works, and at this time, the output module receives the current from the voltage stabilizing block and the protection module.

[0005] Compared with the prior art, the technical effects achieved by adopting the technical scheme are that the voltage input by the input module is reduced by the setting of the protection module, the current passing through the voltage stabilizing block is reduced, the temperature rise of the voltage stabilizing block is reduced, the voltage stabilizing block can work normally without installing a heat dissipation device, the overall structure of the circuit is also simpler, the voltage reduced by the protection module can be selected in multiple ways, and the current limiting circuit can be applied to various voltage reduction power supply circuits.

[0006] In an embodiment of the present application, the protection module comprises: a first triode, the emitter and the collector of the first triode are electrically connected with the input module respectively; and a third triode, the emitter of the third triode is electrically connected with the output module; wherein after the third triode is turned on, the current flows to the base of the first triode through the collector of the third triode and turns on the first triode.

[0007] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by setting the first and third transistors, most of the current output from the input module will not flow directly through the voltage regulator, but will pass through the voltage regulator again after being limited by the first and third transistors, which greatly reduces the current flowing through the voltage regulator and reduces the temperature rise of the voltage regulator.

[0008] In one embodiment of the present invention, the protection module further includes: a second transistor, the collector of which is connected to the base of a third transistor, and the emitter of which is connected to the input module; wherein the second transistor controls the conduction of the third transistor, and the third transistor controls the conduction of the first transistor.

[0009] Compared with existing technologies, the technical effect achieved by this technical solution is as follows: the setting of the second transistor allows the first transistor to be cut off when it fails after being on for a long time, preventing current that has not been limited from flowing out of the first transistor into the voltage regulator, which would cause the output current to exceed the limit current inside the voltage regulator and damage the voltage regulator.

[0010] In one embodiment of the present invention, the protection module further includes: a first protection resistor, which is electrically connected to the base of the first transistor and the input module respectively; and a second protection resistor, which is connected to the base of the first transistor and the collector of the third transistor respectively; wherein the first protection resistor and the second protection resistor can reduce the voltage of the base of the first transistor.

[0011] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the setting of the first protection resistor and the second protection resistor makes the conduction of the first transistor smoother, and also prevents the first transistor from being damaged before the protection effect of the second transistor takes effect during continuous operation, thus protecting the stability of the module. By changing the resistance values ​​of the first protection resistor and the second protection resistor, the desired current limiting value can be modified accordingly, increasing the practicality of the current limiting circuit.

[0012] In one embodiment of the present invention, the circuit further includes a voltage divider resistor, one end of which is electrically connected to the input module and the other end of which is electrically connected to the collector of the first transistor.

[0013] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the setting of the voltage divider resistor ensures that the current flowing through the voltage regulator block when the first transistor is in the off state will not exceed the internal limit current, and it can also divert some current when the first transistor is in the on state, reducing the current that the protection module needs to limit and reducing the difficulty of current limiting.

[0014] In one embodiment of the present invention, the circuit further includes a current-limiting resistor, one end of which is electrically connected to the output module and the other end of which is electrically connected to the collector of the second transistor.

[0015] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the setting of the current limiting resistor allows the second transistor to be turned on smoothly during operation, and allows the second and third transistors to be connected in series to achieve simultaneous cut-off and simultaneous turn-on, thereby increasing the working efficiency of the current limiting circuit and reducing the buffer time during the operation of the current limiting circuit.

[0016] In one embodiment of the present invention, it further includes: when the first transistor and the third transistor are turned off, the current enters the voltage regulator block after passing through the voltage divider resistor.

[0017] Compared with existing technologies, the technical effects achieved by this solution are as follows: when the first transistor needs adjustment due to long-term operation, the voltage divider resistor can ensure that the current flowing through the voltage regulator does not exceed the current that the voltage regulator can withstand, and can also avoid accidents caused by sudden damage to the second and third transistors, thus increasing the safety of the circuit.

[0018] In one embodiment of the present invention, the input module includes: a power supply device, which is electrically connected to the protection module and the voltage regulator block respectively; and a first filter capacitor, which is connected in parallel with the power supply device.

[0019] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: the power supply equipment provides energy for the operation of the voltage regulator, improves the voltage regulator's endurance, and allows the voltage regulator to work for a long time; the first filter capacitor makes the voltage provided by the power supply equipment more stable, increasing the stability of the circuit.

[0020] In one embodiment of the present invention, the output module further includes: an energy storage device, which is electrically connected to the protection module and the voltage regulator respectively; and a second filter capacitor, which is connected in parallel with the energy storage device.

[0021] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: the installation of energy storage equipment increases energy utilization, and the second filter capacitor makes the voltage output by the energy storage equipment to the external load more stable.

[0022] In one embodiment of the present invention, it further includes: an air conditioner, wherein the current limiting circuit is disposed in the air conditioner and electrically connected to the air conditioner, and the circuit has all the technical features of the above-mentioned circuit, which will not be described in detail here.

[0023] In one embodiment of the present invention, it further includes: a step-down circuit, and the current limiting circuit for reducing the temperature rise of the voltage regulator is applicable to various step-down power supply circuits. The current limiting circuit for reducing the temperature rise of the voltage regulator has all the technical features of the above-mentioned circuit, which will not be described in detail here. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the specific circuit of the present invention;

[0025] Figure 2 This is a system diagram of the present invention.

[0026] Explanation of reference numerals in the attached figures:

[0027] 100 - Input module; 110 - Power supply equipment; 120 - First filter capacitor; 200 - Protection module; 210 - First transistor; 220 - Second transistor; 230 - Third transistor; 240 - First protection resistor; 250 - Second protection resistor; 260 - Current limiting resistor; 300 - Output module; 310 - Energy storage device; 320 - Second filter capacitor; 330 - Voltage divider resistor; 400 - Voltage regulator; 500 - Air conditioner; 600 - Circuit. Detailed Implementation

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0029] [First Embodiment]

[0030] See Figure 1 This embodiment provides a circuit 600 for reducing temperature rise. The circuit 600 includes: an input module 100, which provides current to the circuit 600; a protection module 200, which is electrically connected to the input module 100; an output module 300, which is electrically connected to the protection module 200; and a voltage regulator 400, which is connected to both the output module and the input module 100. The circuit 600 is applied to a switching power supply. The input module 100 regulates the input voltage. The current generated by the regulated voltage passes through the voltage regulator 400. A portion of the protection module 200 is connected in parallel with the voltage regulator 400. Most of the current enters the protection module 200 at this time, reducing the current required by the voltage regulator 400. At this time, the output module 300 receives the current from the voltage regulator 400 and the protection module 200.

[0031] Input module 100 provides the input current for the entire circuit 600. Protection module 200 and voltage regulator 400 are both electrically connected to input module 100. In related technologies, the current output from the power supply directly passes through voltage regulator 400, causing excessive temperature rise in voltage regulator 400. During operation, heat dissipation devices need to be added, making the structure of circuit 600 more complex. The protection module allows a small portion of the current to pass directly through voltage regulator 400, while most of the current flows to output module 300 after being current-limited by the protection module, thereby reducing the temperature rise of voltage regulator 400 itself.

[0032] During operation, the input module 100 regulates the input voltage. The current generated by the regulated voltage passes through the voltage regulator 400. Part of the protection module 200 is connected in parallel with the voltage regulator 400. Most of the current enters the protection module 200 at this time, reducing the current of the voltage regulator 400 during operation. At this time, the output module receives the current from the voltage regulator 400 and the protection module 200, and the voltage at the output module terminal decreases.

[0033] Preferably, circuit 600 can be applied to step-down conversion of switching power supplies and BUCK power supplies. The output module supplies power to the subsequent output load and reduces the voltage of input module 100, such as 18V to 15V, 15V to 12V, 12V to 3.3V, etc.

[0034] The protection module 200 reduces the input voltage of the input module 100, thereby reducing the current flowing through the voltage regulator 400 and decreasing the temperature rise of the voltage regulator 400. This allows the voltage regulator 400 to operate normally without the need for a heat sink, and also simplifies the overall structure of the circuit 600. The voltage reduction provided by the protection module 200 can be selected in various ways, making the current limiting circuit 600 suitable for a variety of step-down power supply circuits 600.

[0035] [Second Embodiment]

[0036] In one specific embodiment, the protection module 200 includes: a first transistor 210, the emitter and collector of the first transistor 210 being electrically connected to the input module 100 respectively; and a third transistor 230, the emitter of the third transistor 230 being electrically connected to the output module; wherein, after the third transistor 230 is turned on, the current flows through the collector of the third transistor 230 to the base of the first transistor 210, and turns on the first transistor 210.

[0037] The collector of the first transistor 210 and the base of the second transistor 220 are located on the side of the voltage regulator 400 near the input module 100, and there are no other electrical components connected between them. The collector of the third transistor 230 is connected to the base of the first transistor 210, and the emitter of the third transistor 230 is directly connected to the input module 100.

[0038] During operation, because the first transistor 210 and the voltage regulator 400 are connected in parallel, part of the current input by the input module 100 flows to the collector of the first transistor 210, and the other part flows to the base of the second transistor 220. A step-down resistor is provided between the input module 100 and the collector of the first transistor 210. After the voltage is reduced by the step-down resistor, the voltage at the base of the second transistor 220 will decrease. Therefore, the voltage at the emitter of the second transistor 220 will be higher than the voltage at the base of the second transistor 220. The second transistor 220 is a PNP type transistor. At this time, the second transistor 220 is turned on. Most of the current at the base of the third transistor 230 flows out from the collector of the third transistor 230. Only a small part of the current output by the input module 100 flows through the voltage regulator 400, which serves to reduce the operating current of the voltage regulator 400. The current flows out from the collector of the third transistor 230 and flows to the base of the first transistor 210.

[0039] Preferably, when the input current of the input module 100 is too large, the current limited by the first transistor 210 and the third transistor 230 will not cause the current through the voltage regulator 400 to be too large, thereby increasing the stability of operation.

[0040] By setting the first transistor 210 and the third transistor 230, most of the current output by the input module 100 will not flow directly through the voltage regulator 400, but will pass through the voltage regulator 400 again after being limited by the first transistor 210 and the third transistor 230. This greatly reduces the current flowing through the voltage regulator 400 and reduces the temperature rise of the voltage regulator 400.

[0041] [Third Embodiment]

[0042] In one specific embodiment, the protection module 200 further includes: a second transistor 220, the collector of the second transistor 220 being connected to the base of the third transistor 230, and the emitter being connected to the input module 100; wherein, the second transistor 220 controls the conduction of the third transistor 230, and the third transistor 230 controls the conduction of the first transistor 210.

[0043] The second transistor 220 is located on the side of the third transistor 230 near the input module 100. The third transistor 230 is an NPN transistor. The base of the third transistor 230 and the collector of the second transistor 220 are on the same wire. The collector of the third transistor 230 and the base of the first transistor 210 are on the same wire. The conduction of the third transistor 230 is controlled according to the conduction status of the second transistor 220.

[0044] The first transistor 210 and the third transistor 230 can already perform current limiting. However, if the first transistor 210 is in a conducting state for a long time during operation, it is prone to damage, causing accidents. Therefore, a second transistor 220 is set between the third transistor 230 and the first transistor 210. When the second transistor 220 is turned on, the current flows to the collector of the second transistor 220, which is also the base of the third transistor 230, and turns on the third transistor 230. After the third transistor 230 is turned on, the current flows out from the collector of the third transistor 230 and into the base of the first transistor 210. At this time, the voltage at the base of the first transistor 210 rises and exceeds the voltage at the emitter of the first transistor 210, so the first transistor 210 is turned off, thus protecting the first transistor 210.

[0045] The second transistor 220 is designed to cut off the first transistor 210 when it fails after being on for a long time. This prevents unlimited current from flowing out of the first transistor 210 and into the voltage regulator 400, which would cause the output current to exceed the limit current inside the voltage regulator 400 and damage the voltage regulator 400.

[0046] [Fourth Embodiment]

[0047] In one specific embodiment, the protection module 200 further includes: a first protection resistor 240, which is electrically connected to the base of the first transistor 210 and the input module 100 respectively; and a second protection resistor 250, which is connected to the base of the first transistor 210 and the collector of the third transistor 230 respectively; wherein the first protection resistor 240 and the second protection resistor 250 can reduce the voltage of the base of the first transistor 210.

[0048] The first protection resistor 240 is located between the emitter and base of the first transistor 210, and the second protection resistor 250 is located between the collector of the third transistor 230 and the base of the first transistor 210.

[0049] During operation, the first protection resistor 240 is connected to the emitter side of the first transistor 210, which has the same voltage as the input voltage of the input module 100. If the first protection resistor 240 is not set, the voltage at the base of the first transistor 210 will be the same as the voltage at the emitter, and the first transistor 210 cannot be turned on. The second protection resistor 250 is used to reduce the current flowing out of the emitter of the third transistor 230. Although there is a certain voltage reduction after passing through the second transistor, the reduction is significantly insufficient compared to the voltage input to the input module 100. Therefore, the second protection resistor 250 is set to reduce the voltage at the base of the first transistor 210. The first protection resistor 240 and the second protection resistor 250 work together to enable the first transistor 210 to conduct. This also allows the current flowing through the first transistor 210 to increase slowly when the current increases. Before the third transistor 230 plays a protective role and cuts off the first transistor 210, the first transistor 210 will not be damaged due to excessive current.

[0050] Preferably, the resistance values ​​of the first protection resistor 240 and the second protection resistor 250 can be adjusted according to the input voltage of the input module 100 and the voltage that the voltage regulator 400 needs to limit. When the amount of current to be reduced is small, the resistance value can be increased appropriately to make it easier for the first transistor 210 to conduct. When the amount of current to be reduced is large, the resistance value can be decreased appropriately. Understandably, the input voltage of the input module 100 can also be directly adjusted to achieve the desired current value after current limiting.

[0051] The setting of the first protection resistor 240 and the second protection resistor 250 makes the conduction of the first transistor 210 smoother, and also prevents the first transistor 210 from being damaged before the protection effect of the second transistor 220 takes effect during continuous operation, thus improving the stability of the protection module 200. By changing the resistance values ​​of the first protection resistor 240 and the second protection resistor 250, the desired current limiting value can be modified accordingly, increasing the practicality of the current limiting circuit 600.

[0052] [Fifth Embodiment]

[0053] In one specific embodiment, the circuit 600 further includes a voltage divider resistor 330, one end of which is electrically connected to the input module 100 and the other end of which is electrically connected to the collector of the first transistor 210.

[0054] The voltage divider resistor 330 is placed between the emitter and collector of the first transistor 210. The voltage divider resistor 330 and the voltage regulator 400 are connected in series to reduce the current flowing through the voltage regulator 400 before current limiting.

[0055] During operation, the current input to the input module 100 passes through the voltage divider resistor 330, the first transistor 210, and the first protection resistor 240. This ensures that the first transistor 210 is conducting while also protecting the voltage regulator 400. When the first transistor 210 needs to stop operating after being conducting for a long time, the protection module 200 no longer limits the current. At this time, the current flows directly through the voltage divider resistor 330. The resistance value of the voltage divider resistor 330 needs to ensure that the operating current is controlled below the limit current inside the voltage regulator 400 without current limiting. When the first transistor 210 is turned on again, the voltage regulator 400 continues to operate normally.

[0056] Preferably, when the current input to the input module 100 changes, the resistance value of the voltage divider resistor 330 also needs to be changed accordingly, so as to ensure that the voltage regulator 400 can continue to work normally.

[0057] The voltage divider resistor 330 ensures that the current flowing through the voltage regulator 400 when the first transistor 210 is in the off state will not exceed the internal limit current. It also diverts some current when the first transistor 210 is in the on state, reducing the current that the protection module 200 needs to limit and reducing the difficulty of current limiting.

[0058] [Sixth Embodiment]

[0059] In one specific embodiment, the circuit 600 further includes a current-limiting resistor 260, one end of which is electrically connected to the output module 300, and the other end of which is electrically connected to the collector of the second transistor 220.

[0060] The current-limiting resistor 260 is placed between the base and emitter of the third transistor 230. The third transistor 230 is an NPN transistor. By setting the current-limiting resistor 260, the voltage at the emitter of the third transistor 230 is reduced. When the second transistor 220 is turned on, the base of the third transistor 230 receives the current from the collector of the second transistor 220. The setting of the current-limiting resistor 260 allows the third transistor 230 to conduct smoothly, allowing the current to flow from the collector of the third transistor 230 to the base of the first transistor 210, thus completing the current limiting of the protection module 200. At the same time, because the current at the base of the third transistor 230 is provided by the collector of the second transistor 220, when the second transistor 220 is turned off, the third transistor 230 is automatically turned off, the base of the first transistor 210 is at a low level, and the first transistor 210 is also turned off.

[0061] The current-limiting resistor 260 allows the second transistor 220 to be turned on smoothly during operation, and allows the second transistor 220 and the third transistor 230 to be connected in series, so that they can be turned off and turned on at the same time. This increases the working efficiency of the current-limiting circuit 600 and reduces the buffer time of the current-limiting circuit 600 during operation.

[0062] [Seventh Embodiment]

[0063] In one specific embodiment, it further includes: when the first transistor 210 and the third transistor 230 are turned off, the current enters the voltage regulator 400 after passing through the voltage divider resistor 330.

[0064] When the third transistor 230 is turned off, the second transistor 220 is also turned off. The base of the first transistor 210 becomes low level, and the first transistor 210 is also turned off. At this time, the current flows directly through the voltage divider resistor 330 into the voltage regulator 400.

[0065] When the first transistor 210 needs adjustment due to long-term operation, the voltage divider resistor 330 can ensure that the current flowing through the voltage regulator 400 does not exceed the current that the voltage regulator 400 can withstand, and can also avoid accidents caused by the sudden damage of the second transistor 220 and the third transistor 230, thus increasing the safety of the circuit 600.

[0066] [Eighth Embodiment]

[0067] In one specific embodiment, the input module 100 includes: a power supply device 110, which is electrically connected to the protection module 200 and the voltage regulator 400 respectively; and a first filter capacitor 120, which is connected in parallel with the power supply device 110.

[0068] The first filter capacitor 120 is connected in parallel with the power supply device 110 and is located on the side of the voltage divider resistor 330 close to the power supply device 110 to stabilize the voltage output by the power supply device 110.

[0069] Preferably, the power supply device 110 can be an electrolytic capacitor, which can store a large amount of electrical energy to ensure that the voltage regulator 400 can work normally when the current limiting current is applied.

[0070] The power supply device 110 provides energy for the operation of the voltage regulator 400, improving the voltage regulator 400's endurance and allowing it to work for a long time. The first filter capacitor 120 makes the voltage provided by the power supply device 110 more stable, increasing the stability of the circuit 600.

[0071] [Ninth Embodiment]

[0072] In one specific embodiment, the output module 300 further includes: an energy storage device 310, which is electrically connected to the protection module 200 and the voltage regulator 400 respectively; and a second filter capacitor 320, which is connected in parallel with the energy storage device 310.

[0073] The output module 300 is connected to the emitter of the third transistor 230. A portion of the current from the emitter of the third transistor 230 is directly output into the output module 300. The output module is used to connect to an external load and provide power to the external load.

[0074] Energy storage device 310 typically uses electrolytic capacitors, which have good energy storage performance. After current limiting, some of the energy can flow directly to energy storage device 310 for storage.

[0075] The installation of energy storage device 310 increases energy utilization, and the second filter capacitor 320 makes the voltage output by energy storage device 310 to external loads more stable.

[0076] [Tenth Embodiment]

[0077] An air conditioner 500 has a current limiting circuit 600 disposed in the air conditioner 500 and electrically connected to the air conditioner 500. The circuit 600 has all the technical features of the circuit 600 described above, which will not be repeated here.

[0078] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A circuit (600) for reducing temperature rise, characterized in that, The circuit (600) includes: Input module (100), the input module (100) inputs current to the circuit (600); A protection module (200) is electrically connected to the input module (100); An output module (300) is electrically connected to the protection module (200); A voltage regulator (400) is connected to the output module (300) and the input module (100) respectively; The circuit (600) is applied to the switching power supply. The input module (100) will regulate the input voltage. The current generated by the regulated voltage passes through the voltage regulator (400). Part of the protection module (200) is connected in parallel with the voltage regulator (400). Most of the current enters the protection module (200) at this time, reducing the current when the voltage regulator (400) is working. At this time, the output module (300) receives the current from the voltage regulator (400) and the protection module (200).

2. The circuit (600) according to claim 1, characterized in that, The protection module (200) includes: The first transistor (210) has its emitter and collector electrically connected to the input module (100), respectively. The emitter of the third transistor (230) is electrically connected to the output module (300); When the third transistor (230) is turned on, the current flows through the collector of the third transistor (230) to the base of the first transistor (210), and turns on the first transistor (210).

3. The circuit (600) according to claim 2, characterized in that, The protection module (200) also includes: The collector of the second transistor (220) is connected to the base of the third transistor (230), and the emitter is connected to the input module (100). The second transistor (220) controls the conduction of the third transistor (230), and the third transistor (230) controls the conduction of the first transistor (210).

4. The circuit (600) according to claim 3, characterized in that, The protection module (200) also includes: The first protection resistor (240) is electrically connected to the base of the first transistor (210) and the input module (100) respectively; The second protection resistor (250) is connected to the base of the first transistor (210) and the collector of the third transistor (230), respectively. The first protection resistor (240) and the second protection resistor (250) can reduce the base voltage of the first transistor (210).

5. The circuit (600) according to claim 2, characterized in that, The circuit (600) further includes: A voltage divider resistor (330) is connected at one end to the input module (100) and at the other end to the collector of the first transistor (210).

6. The circuit (600) according to claim 3, characterized in that, The circuit (600) further includes: A current-limiting resistor (260) is provided, one end of which is electrically connected to the output module (300), and the other end of which is electrically connected to the collector of the second transistor (220).

7. The circuit (600) according to claim 5, characterized in that, When the first transistor (210) and the third transistor (230) are turned off, the current enters the voltage regulator (400) after passing through the voltage divider resistor (330).

8. The circuit (600) according to any one of claims 1 to 7, characterized in that, The input module (100) includes: Power supply equipment (110), which is electrically connected to the protection module (200) and the voltage regulator (400) respectively; The first filter capacitor (120) is connected in parallel with the power supply device (110).

9. The circuit (600) according to claim 8, characterized in that, The output module (300) further includes: An energy storage device (310) is electrically connected to the protection module (200) and the voltage regulator (400) respectively; The second filter capacitor (320) is connected in parallel with the energy storage device (310).

10. An air conditioner (500), characterized in that, The circuit (600) as described in any one of claims 1 to 8 is provided in the air conditioner (500) and is electrically connected to the air conditioner (500).

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