Refrigerator

Abstract

The invention relates to a refrigerator. The refrigerator comprises a lamp panel, a power supply access end and a driving circuit, the lamp panel comprises a light-emitting device, the power supply access end is used for accessing power supply voltages of different voltage grades, and the driving circuit drives the light-emitting device to emit light according to the power supply voltages. The driving circuit comprises a switching control circuit, a plurality of resistor assemblies and a plurality of switching circuits, the head ends and the tail ends of the resistor assemblies are connected in sequence, and the head end of the first resistor assembly is connected with the power supply access end. The first end of each switch circuit is correspondingly connected with the tail end of one resistor assembly, and the second end of each switch circuit is connected with the light-emitting device. And the switching control circuit is connected with the power supply access end and the control ends of the switching circuits except the switching circuit connected with the last resistor assembly. The plurality of switch circuits are switched on in a time-sharing manner, and the resistance value of the resistor assembly between the first end of the switch circuit in the switched-on state and the power supply access end is matched with the current voltage grade of the power supply voltage, so that the power supply voltage of different voltage grades is adapted.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a refrigerator. Background Technology

[0002] With the rapid development of technology, refrigerators are being used more and more widely. Refrigerators typically have panels installed to provide functions such as lighting, progress display, and operation feedback, making them convenient for users.

[0003] Because different refrigerator models supply different voltage levels to the lamp panels (5V, 12V, 24V, etc.), a dedicated impedance-matching circuit board needs to be designed for each voltage level to ensure consistent lamp panel brightness across different voltage levels. However, this method requires a wide variety of circuit boards, resulting in high material management costs. Summary of the Invention

[0004] Therefore, it is necessary to provide a refrigerator that includes a lamp board drive circuit that can adapt to different voltage levels in order to reduce the management cost of refrigerator materials.

[0005] A refrigerator, comprising:

[0006] Light panel, including light-emitting devices;

[0007] The power input terminal is used to connect to power supply voltages of different voltage levels;

[0008] A driving circuit, connected to the power input terminal and the light-emitting device, is used to drive the light-emitting device to emit light according to the power supply voltage; wherein, the driving circuit includes:

[0009] Multiple resistor components, with the first and last ends of each resistor component connected sequentially, and the first end of the first resistor component connected to the power input terminal.

[0010] Multiple switching circuits, the first end of each switching circuit is connected to the end of a resistor component, and the second end of each switching circuit is connected to the light-emitting device.

[0011] The switching control circuit is connected to the power input terminal and also to the control terminals of each of the switching circuits other than the one connected to the last resistor assembly. The multiple switching circuits are used for time-division multiplexing, the voltage division of the control terminal of the switching circuit in the on state is greater than the on-state voltage, and the resistance value of the resistor assembly between the first terminal of the on-state switching circuit and the power input terminal matches the current voltage level of the power supply voltage.

[0012] In the aforementioned refrigerator, when the drive circuit is connected to the power supply voltage, each switching circuit is turned on in a time-sharing manner. The resistance value of the resistor component between the first terminal of the switching circuit in the on state and the power supply input terminal matches the current voltage level of the power supply. Therefore, this drive circuit can adapt to different power supply voltage levels, providing the expected drive current to the light-emitting device. Consequently, this drive circuit can be used in various refrigerator models, eliminating the need to manage multiple circuit boards or replace corresponding circuit boards based on specific refrigerator models. This significantly reduces refrigerator material management costs and improves assembly efficiency.

[0013] In some embodiments, the switching circuit includes a switching transistor, a first resistor, and a second resistor; the first terminal of the switching transistor serves as the first terminal of the switching circuit, the second terminal of the switching transistor serves as the second terminal of the switching circuit, the control terminal of the switching transistor is connected to the first terminal of the first resistor and the first terminal of the second resistor respectively, and the control terminal of the switching transistor serves as the control terminal of the switching circuit; the second terminal of the first resistor is connected to the first terminal of the switching transistor, and the second terminal of the second resistor is grounded; the switching transistor is used to turn on when the voltage at the control terminal reaches the turn-on voltage.

[0014] In this embodiment, each switching transistor can be turned on in a time-division manner. The total resistance between the first end of the switching transistor in the on state and the power input terminal is matched with the current voltage level of the power supply voltage. The driving current output to the light-emitting device is equal under each voltage level, and the brightness of light emission is more consistent under each voltage level.

[0015] In some embodiments, the switching control circuit includes a plurality of detection control units, the number of which is one less than the number of the switching circuits. The detection terminal of each detection control unit is connected to the power input terminal, and the switching control terminal of each detection control unit is connected to the control electrode of a switching transistor.

[0016] The detection and control unit is used to control the corresponding switch to turn off according to the current voltage level of the power supply voltage, so that the resistance value of the resistor component between the switch in the on state and the power input terminal matches the current voltage level.

[0017] In this embodiment, by setting up multiple detection control units, each corresponding to a voltage level other than the highest one, and controlling the corresponding switching transistor to turn off, accurate time-sharing conduction of each switching transistor can be achieved. This method, where each detection control unit is responsible for detecting different voltage levels, offers high detection accuracy and reliability.

[0018] In some embodiments, the detection control unit includes a Zener diode and a transistor; the cathode of the Zener diode is connected to the power input terminal, the anode of the Zener diode is connected to the base of the transistor, the collector of the transistor is connected to the control terminal of the switching transistor, and the emitter of the transistor is grounded; the breakdown voltage of the Zener diode in each detection control unit corresponds to the other voltage levels besides the highest level of the power supply voltage.

[0019] The breakdown voltage of the Zener diode in each of the detection and control units is positively correlated with the resistance value of the resistor assembly between the first terminal of the corresponding switch circuit and the power input terminal.

[0020] In this embodiment, each detection and control unit uses an analog circuit structure of Zener diodes and transistors to achieve automatic identification of multiple voltage levels and precise switching of switching circuits. Moreover, the circuit structure is simple and easier to control costs compared to using digital circuits.

[0021] In some embodiments, the switching transistor is a MOS transistor, with the drain of the MOS transistor being the first terminal, the source being the second terminal, and the gate being the control terminal.

[0022] Because the extremely small voltage drop between the drain and source of a MOSFET in the on state can reduce switching losses, and because MOSFETs have a fast switching speed, using MOSFETs as switching transistors can improve the reliability of light emission control in light-emitting devices.

[0023] In some embodiments, the driving circuit further includes a discharge unit, wherein the first end of the discharge unit and the anode of the light-emitting device are both connected to the second electrode of the switching transistor, and the second end of the discharge unit and the cathode of the light-emitting device are both grounded.

[0024] In this embodiment, by setting up a discharge unit, the discharge of charge in the parasitic capacitor can be accelerated, thereby improving the service life of the MOSFET and the safety of the circuit.

[0025] In some embodiments, the discharge unit includes a discharge resistor connected in parallel with the light-emitting device.

[0026] In this embodiment, the impedance of the discharge resistor is much lower than the impedance of the light-emitting device when it is turned off, which can quickly discharge the gate charge when the MOSFET is turned off, so that the MOSFET can enter the cut-off state more quickly.

[0027] In some embodiments, the resistance value of the bleeder resistor is equal to the resistance value of the second resistor.

[0028] In this embodiment, by making the value of the bleeder resistor equal to the value of the second resistor, the gate voltage change during the switching process of the MOS transistor between conduction and cutoff can be made more stable and symmetrical, thereby improving the reliability of the drive circuit.

[0029] In some embodiments, the resistance values ​​of each of the resistor components gradually increase according to the connection sequence.

[0030] In this embodiment, by gradually increasing the resistance value of each resistor component according to the connection sequence, the voltage at the end of each resistor component is distributed according to the resistance ratio under the voltage division principle of the series circuit. Since the first terminal of the switching transistor is connected to the end of the resistor component, the voltage at the first terminal of each switching transistor can be matched with each voltage level. This allows the voltage at the control terminal of the switching transistor corresponding to the current voltage level to reach the turn-on voltage, thereby precisely controlling the on and off states of the corresponding switching transistor. This, in turn, coordinates with the switching control circuit to ensure that each switching transistor is precisely turned on in a time-sharing manner, thus improving the reliability of the light-emitting device driving.

[0031] In some embodiments, the light-emitting device includes a light-emitting diode, the anode of which is connected to the second terminal of each of the switching circuits, and the cathode of which is grounded. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 Schematic diagrams of a refrigerator module provided for some embodiments of this application;

[0034] Figure 2 Schematic diagram of a refrigerator module provided for other embodiments of this application;

[0035] Figure 3 This is a schematic diagram of the structure of the driving circuit provided in some embodiments of this application;

[0036] Figure 4 This is a schematic diagram of the structure of the driving circuit provided in some other embodiments of this application;

[0037] Figure 5 This is a schematic diagram of the structure of a driving circuit provided in some embodiments of this application. Detailed Implementation

[0038] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0040] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0041] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0042] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0043] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0044] In some embodiments, a refrigerator is provided, such as Figure 1 As shown, the refrigerator includes a light panel 100, a driving circuit 200, and a power input terminal 300. The light panel 100 includes a light-emitting device, which may include LEDs (Light Emitting Diodes) or other devices. The number of LEDs in the light-emitting device is not limited and can be set according to actual needs (such as the required brightness, the size parameters of the brightness display area, etc.). For example, the light-emitting device includes multiple LEDs, which can be connected in series, parallel, or a combination of series and parallel connections.

[0045] The power input terminal 300 is used to connect to power supply voltages of different levels, which may vary depending on the refrigerator model. For example, the power input terminal 300 is used to connect to a power conversion module in the refrigerator to receive the power supply voltage. The level of the power supply voltage output by the power conversion module may differ depending on the refrigerator model. As an example, the power conversion module in different refrigerator models may provide a DC voltage of 5V, 12V, or 24V.

[0046] The input terminal of the driver circuit 200 is connected to the power input terminal 300, and the output terminal is connected to the light-emitting device in the lamp board 100. It receives the power supply voltage from the power input terminal 300 and drives the light-emitting device to emit light according to the power supply voltage. When the light-emitting device includes multiple LEDs, if the LEDs are connected in series, the anode of the first LED in the series connection is connected to the output terminal of the driver circuit 200 as the anode of the light-emitting device, and the cathode of the last LED in the series connection is grounded. If the LEDs are connected in parallel, the anodes of each LED are connected to the output terminal of the driver circuit 200 as the anodes of the light-emitting device, and the cathodes of each LED are grounded. If multiple LEDs are connected in a mixed series and parallel configuration, the connection to the output terminal of the driver circuit 200 can be determined according to the actual situation.

[0047] When the power supply voltage level changes, the drive circuit 200 switches its internal impedance to match the power supply voltage level so that the drive current output to the light-emitting device is close to or equal when different power supply voltage levels are input (the difference in drive current output by the drive circuit 200 can be considered equal within an acceptable error range when different power supply voltage levels are connected), and the brightness of each light-emitting device is the same or close, thereby making the brightness uniformity of the lamp board 100 higher.

[0048] In some embodiments, the drive circuit 200 includes a switching control circuit, a plurality of resistor components, and a plurality of switching circuits. The number of resistor components and switching circuits are the same, and they are connected accordingly.

[0049] The first and last ends of each resistor assembly are connected sequentially, with the first end of the first resistor assembly connected to the power input terminal. The first end of each switching circuit is connected to the last end of a corresponding resistor assembly, and the second end of each switching circuit is connected to a light-emitting device.

[0050] The switching control circuit is connected to the power input terminal 300, and also to the control terminals of all switching circuits except the one connected to the last resistor assembly. Multiple switching circuits are used for time-division multiplexing. The voltage division at the control terminal of a switching circuit in the on state is greater than the on-state voltage, and the resistance value of the resistor assembly between the first terminal of the on-state switching circuit and the power input terminal matches the current voltage level of the supply voltage.

[0051] The switching control circuit controls the on / off state of each switching circuit except the one connected to the last resistor component, based on the supply voltage. Under the action of the switching control circuit and the voltage divider, multiple switching circuits are turned on in a time-sharing manner. The resistance value of the resistor component between the first terminal of the switching circuit in the on state and the power input terminal 300 matches the current voltage level of the supply voltage, thereby ensuring that the drive current output to the light-emitting device is the expected current.

[0052] For ease of understanding, Figure 2 For example, there are three resistor components and three switch circuits: first resistor component 211, second resistor component 212, third resistor component 213, first switch circuit 221, second switch circuit 222, and third switch circuit 223.

[0053] The first resistor assembly 211, the second resistor assembly 212, and the third resistor assembly 213 are connected sequentially at their beginning and end points, with the beginning point of the first resistor assembly 211 connected to the power input terminal 330. The first end of the first switch circuit 221 is connected to the end point of the first resistor assembly 211, the first end of the second switch circuit 222 is connected to the end point of the second resistor assembly 212, and the first end of the third switch circuit 223 is connected to the end point of the third resistor assembly 213. The second ends of the first switch circuit 221, the second switch circuit 222, and the third switch circuit 223 are all connected to a light-emitting device (LED1 shown in the figure).

[0054] The switching control circuit 230 is connected to the power input terminal 300, and also to the control terminals of each switching circuit except the third switching circuit 223, which is connected to the third resistor component 213 located at the end. That is, the switching control circuit 230 is connected to the control terminals of the first switching circuit 221 and the second switching circuit 222 respectively.

[0055] The first switching circuit 221, the second switching circuit 222, and the third switching circuit 223 are turned on in a time-division manner. When the supply voltage level is the lowest (e.g., 5V), the voltage divider at the control terminal of the first switching circuit 221 is greater than the turn-on voltage, and the first switching circuit 221 is turned on. At this time, the supply voltage is output to the light-emitting device LED1 through the first resistor component 211 that matches the current voltage level, and the driving current of the light-emitting device LED1 is the expected current.

[0056] When the power supply voltage is at its highest level (e.g., 24V), the switching control circuit 230 controls the first switching circuit 221 and the second switching circuit 222 to turn off according to the voltage level, and the third switching circuit 223 is turned on independently. The power supply voltage is output to the light-emitting device LED1 through the first resistor component 211, the second resistor component 212, and the third resistor component 213 (the total impedance of the first resistor component 211, the second resistor component 212, and the third resistor component 213 is matched with the 24V voltage). The driving current of the light-emitting device LED1 is the expected current.

[0057] When the supply voltage is between the highest and lowest levels (e.g., 12V), the switching control circuit 230 controls the first switching circuit 221 to turn off according to the voltage level, and the second switching circuit 222 turns on independently. The supply voltage is output to the light-emitting device LED1 through the first resistor component 211 and the second resistor component 212 (the total impedance of the first resistor component 211 and the second resistor component 212 is matched with the 12V voltage). The driving current of the light-emitting device LED1 is the expected current.

[0058] In the aforementioned refrigerator, when the drive circuit 200 is connected to the power supply voltage, each switching circuit is turned on in a time-sharing manner. The resistance value of the resistor component between the first terminal of the switching circuit in the on state and the power input terminal matches the current voltage level of the power supply. Therefore, the drive circuit 200 can adaptively provide the expected drive current to the light-emitting device at different power supply voltage levels. Consequently, this drive circuit 200 can be used for various refrigerator models, eliminating the need to manage multiple circuit boards or replace corresponding circuit boards based on specific refrigerator models. This significantly reduces refrigerator material management costs and improves assembly efficiency.

[0059] In some embodiments, the resistor assembly includes voltage divider resistors, with the start and end points of each voltage divider resistor connected sequentially, and the end point of each voltage divider resistor corresponding to a switching circuit. This embodiment uses resistors to provide impedance, resulting in a simple circuit structure and easy cost control. In other embodiments, the resistor assembly can also use other devices capable of providing impedance, depending on the specific circumstances.

[0060] In some embodiments, the switching circuit includes a switching transistor, a first resistor, and a second resistor. The first terminal of the switching transistor serves as the first terminal of the switching circuit, and the second terminal of the switching transistor serves as the second terminal of the switching circuit. The control terminal of the switching transistor is connected to the first terminal of both the first and second resistors, serving as the control terminal of the switching circuit. The second terminal of the second resistor is grounded. The switching transistor is used to turn on when the voltage at the control terminal reaches the turn-on voltage.

[0061] Taking an example where there are 3 resistors and 3 switches, refer to Figure 3The three resistors are designated as the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3. Each switching circuit includes a switching transistor M1, a first resistor R4, and a second resistor R5. The first terminal of the switching transistor M1 serves as the first terminal of the switching circuit and is connected to the corresponding voltage divider resistor. The second terminal of the switching transistor M1 serves as the second terminal of the switching circuit and is connected to the light-emitting device LED1. The control terminal of the switching transistor M1 is connected to the first terminal of both the first resistor R4 and the first terminal of both the first and second resistors R5, serving as the control terminal of the switching circuit. The second terminal of the first resistor R4 is connected to the first terminal of the switching transistor M1, and the second terminal of the second resistor R5 is grounded. The switching transistor M1 is used to turn on when the voltage at the control terminal reaches the turn-on voltage.

[0062] In this circuit, the switching transistor M1 in the first switching circuit 221, the second switching circuit 222, and the third switching circuit 223 is turned on in a time-sharing manner. When the supply voltage level is the lowest level (e.g., 5V), after the voltage is divided by the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3, the voltage of the control electrode of the switching transistor M1 in the first switching circuit 221 connected to the first voltage divider resistor R1 reaches the turn-on voltage, and the switching transistor M1 is turned on. At this time, the supply voltage is output to the light-emitting device LED1 through the first voltage divider resistor R1, and the driving current of the light-emitting device LED1 is the expected current (no specific value is required).

[0063] When the supply voltage is at its highest level (e.g., 24V), after the voltage is divided by the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3, the control electrode voltage of the switching transistor M1 in the first switching circuit 221, the second switching circuit 222, and the third switching circuit 223 all reach the turn-on voltage. At this time, the switching control circuit 230 controls the control electrode voltage of the switching transistor M1 in the first switching circuit 221 and the second switching circuit 222 to decrease according to the voltage level, turning off these two switching transistors M1, while the switching transistor M1 in the third switching circuit 223 turns on independently. The supply voltage is output to the light-emitting device LED1 through the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3, and the driving current of the light-emitting device LED1 is the expected current.

[0064] When the supply voltage is between the highest and lowest levels (e.g., 12V), after the voltage is divided by the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3, the control electrode voltage of the switching transistor M1 in the first switching circuit 221 and the second switching circuit 222 reaches the turn-on voltage. At this time, the switching control circuit 230 controls the control electrode voltage of the switching transistor M1 in the first switching circuit 221 to decrease according to the voltage level, turning off the switching transistor M1, while the switching transistor M1 in the second switching circuit 222 turns on independently. The supply voltage is output to the light-emitting device LED1 through the first voltage divider resistor R1 and the second voltage divider resistor R2, and the driving current of the light-emitting device LED1 is the expected current.

[0065] In this embodiment, each switching transistor can be turned on in a time-division manner. The total resistance between the first end of the switching transistor in the on state and the power input terminal is matched with the current voltage level of the power supply voltage. The driving current output to the light-emitting device LED1 is equal under each voltage level, and the brightness of light emission is more consistent under each voltage level.

[0066] The resistance values ​​of each resistor can be set according to actual conditions. In some embodiments, the resistance values ​​of each resistor component gradually increase according to the connection sequence. Thus, by gradually increasing the resistance values ​​of each resistor component according to the connection sequence, the voltage at the end of each resistor component is distributed according to the resistance ratio under the voltage divider principle of the series circuit. Since the first terminal of the switching transistor is connected to the end of the resistor component, the voltage at the first terminal of each switching transistor can be matched with each voltage level. This allows the voltage at the control terminal of the switching transistor corresponding to the current voltage level to reach the turn-on voltage, precisely controlling the on and off states of the corresponding switching transistor. This, in turn, coordinates with the switching control circuit 230 to ensure precise time-sharing conduction of each switching transistor, thereby improving the reliability of driving the LED1 light-emitting device.

[0067] In some embodiments, such as Figure 3 As shown, the refrigerator also includes a power supply V1, which outputs a power supply voltage to the drive circuit 200 through a power input terminal. The level of the power supply voltage provided by power supply V1 may vary depending on the refrigerator model.

[0068] The structure of the switching control circuit 230 is not unique. In some embodiments, the switching control circuit 230 may include a voltage sampling circuit (such as a voltage divider sampling circuit) and a controller. The controller is connected to the switching transistors in each switching circuit other than the switching circuit connected to the last resistor component. The voltage sampling circuit is connected to the power input terminal 300, samples and outputs the corresponding sampled voltage signal to the controller. The controller determines the voltage level of the supply voltage based on the sampled voltage signal and controls the state of the corresponding switching transistor, which can realize the time-sharing conduction of each switching transistor.

[0069] In some embodiments, the switching control circuit 230 includes multiple detection control units, the number of which is one less than the number of switching circuits. The detection terminal of each detection control unit is connected to the power input terminal 300, and the switching control terminal of each detection control unit is connected to the control electrode of a switching transistor. The detection control unit is used to control the corresponding switching transistor to turn off according to the current voltage level of the power supply voltage, so that the resistance value of the resistor assembly between the conducting switching transistor and the power input terminal matches the current voltage level.

[0070] Each detection control unit is used to detect different voltage levels, ranging from the highest level to the lowest. As the connected resistor components change sequentially from the first end to the last end of the connected switching transistors, the voltage level used by each detection control unit gradually increases.

[0071] Specifically, with Figure 4 For example, there are three switching circuits and two detection control units, namely a first detection control unit 231 and a second detection control unit 232. The detection terminal of the first detection control unit 231 is connected to the power input terminal 300, and the switching control terminal is connected to the control electrode of the switching transistor M1 in the first switching circuit 221. The detection terminal of the second detection control unit 232 is connected to the power input terminal 300, and the switching control terminal is connected to the control electrode of the switching transistor M1 in the second switching circuit 222.

[0072] The first detection control unit 231 is used to detect the 12V power supply voltage. When the detected power supply voltage reaches 12V, it pulls down the control electrode voltage of the switching transistor M1 in the first switching circuit 221, turning it off. At this time, under the action of the voltage divider, the switching transistor M1 in the second switching circuit 222 is turned on independently.

[0073] The second detection control unit 232 is used to detect the 24V power supply voltage. When the detected power supply voltage reaches 24V, it pulls down the control electrode voltage of the switch transistor M1 in the second switching circuit 222, turning it off. At this time, the switch transistor M1 in the first switching circuit 221 is turned off under the control of the first detection control unit 231. The switch transistor M1 in the third switching circuit 223 is turned on independently.

[0074] In this embodiment, by setting up multiple detection control units, each corresponding to a voltage level other than the highest one, and controlling the corresponding switching transistor to turn off, accurate time-sharing conduction of each switching transistor can be achieved. This method, where each detection control unit is responsible for detecting different voltage levels, ensures high detection accuracy and reliability.

[0075] In some embodiments, the detection control unit includes a Zener diode and a transistor. The cathode of the Zener diode is connected to the power input terminal 300, the anode of the Zener diode is connected to the base of the transistor, the collector of the transistor is connected to the control terminal of the switching transistor, and the emitter of the transistor is grounded. The breakdown voltage of the Zener diode in the detection control unit corresponds to each of the voltage levels other than the highest level in the supply voltage range.

[0076] The breakdown voltage of the Zener diode in the detection control unit is positively correlated with the resistance value of the resistor component between the first terminal of the corresponding connected switching circuit and the power input terminal.

[0077] As the total resistance between the first terminal of the connected switching circuit and the power input terminal 300 increases, the breakdown voltage of the Zener diode in the detection control unit increases.

[0078] For example, with Figure 5 For example, both the first detection control unit 231 and the second detection control unit 232 include a Zener diode D1 and a transistor Q1. The cathode of the Zener diode D1 is connected to the power input terminal 300, the anode of the Zener diode D1 is connected to the base of the transistor Q1, and the emitter of the transistor Q1 is grounded. The collector of the transistor Q1 in the first detection control unit 231 is connected to the control electrode of the switch M1 in the first switching circuit 221, and the collector of the transistor Q1 in the second detection control unit 232 is connected to the control electrode of the switch M1 in the second switching circuit 222.

[0079] As the total resistance between the first terminal of the connected switching circuit and the power input terminal 300 increases, the breakdown voltage of the Zener diode D1 in the detection control unit increases. Furthermore, the breakdown voltage of the Zener diode D1 in the first detection control unit 231 corresponds to the 12V power supply voltage, and the breakdown voltage of the Zener diode D1 in the second detection control unit 232 corresponds to the 24V power supply voltage.

[0080] When a 12V power supply voltage is input, the Zener diode D1 in the first detection control unit 231 is broken down, causing the connected transistor Q1 to conduct, which pulls down the control electrode of the corresponding switch M1, turning off switch M1. When a 24V power supply voltage is input, the Zener diode D1 in both detection control units is broken down, causing the connected transistor Q1 to conduct, which pulls down the control electrode of the corresponding switch M1, turning off both corresponding switches M1.

[0081] In this embodiment, each detection and control unit uses an analog circuit structure of Zener diodes and transistors to achieve automatic identification of multiple voltage levels and precise switching of switching circuits. Moreover, the circuit structure is simple and easier to control costs compared to using digital circuits.

[0082] The type of each switching transistor can be flexibly selected according to the actual situation. In some embodiments, each switching transistor can be a triode, and its terminals are determined according to the specific situation.

[0083] In other embodiments, each switch is a MOS (Metal Oxide Semiconductor Field-Effect Transistor). Exemplarily, the MOS transistor is an NMOS transistor, with its drain as the first terminal, its source as the second terminal, and its gate as the control terminal. The turn-on threshold voltage of the MOS transistor is the turn-on voltage of the switch.

[0084] Because the extremely small voltage drop between the drain and source of a MOSFET in the on state can reduce switching losses, and because MOSFETs have a fast switching speed, using a MOSFET as a switching transistor can improve the reliability of the light-emitting control of the LED1.

[0085] In some embodiments, the driving circuit 200 further includes a discharge unit 240. The first end of the discharge unit 240 and the anode of the light-emitting device LED1 are both connected to the second electrode of the switching transistor, and the second end of the discharge unit 240 and the cathode of the light-emitting device LED1 are both grounded.

[0086] It should be noted that there is a parasitic capacitance between the gate and source of the MOSFET. When the MOSFET is turned off, the electrical energy in the parasitic capacitance will be discharged through the light-emitting device LED1. At this time, the impedance of the light-emitting device LED1 is very high, the discharge speed is slow, and it may cause the LED to be dimly lit or flicker.

[0087] In this embodiment, by setting up the discharge unit 240, the discharge of charge in the parasitic capacitor can be accelerated, thereby improving the service life of the MOSFET and the safety of the circuit.

[0088] In some embodiments, the discharge unit 240 includes a discharge resistor R6, which is connected in parallel with the light-emitting device LED1.

[0089] In this embodiment, the impedance of the discharge resistor R6 is much lower than the impedance of the light-emitting device LED1 when it is turned off, which can quickly discharge the gate charge when the MOS transistor is turned off, so that the MOS transistor can enter the cut-off state more quickly.

[0090] The resistance value of the bleeder resistor R6 can be flexibly set according to specific circumstances. In some embodiments, the resistance value of the bleeder resistor R6 is equal to the resistance value of the second resistor.

[0091] In this embodiment, by making the resistance value of the bleeder resistor R6 equal to the resistance value of the second resistor, the gate voltage change during the switching process of the MOS transistor on and off can be made more stable and symmetrical, thereby improving the reliability of the drive circuit.

[0092] To better understand the above embodiments, an optional embodiment will be explained in detail below. Please refer to... Figure 5 When a 5V power supply voltage is input, the Zener diode D1 in the first detection control unit 231 and the second detection control unit 232 does not meet the breakdown voltage requirement, and the transistor Q1 in the first detection control unit 231 and the second detection control unit 232 is disconnected. After passing through a voltage divider network of multiple voltage divider resistors, the turn-on threshold voltage of the NMOS transistor in the second switch circuit 222 and the third switch circuit 223 meets the turn-on condition, and the power supply V1—first voltage divider resistor R1—NMOS in the first switch circuit 221—light-emitting device LED1 forms a closed path, and the light-emitting device LED1 is turned on.

[0093] When a 12V power supply voltage is input, the Zener diode D1 in the first detection and control unit 231 breaks down due to its breakdown voltage, causing the transistor Q1 in the first detection and control unit 231 to conduct. Consequently, the gate voltage of the NMOS transistor in the first switching circuit 221 becomes 0V, and the NMOS transistor is turned off. At this time, the gate voltage of the NMOS transistor in the third switching circuit 223 is insufficient to meet the turn-on condition after passing through the voltage divider network, and the turn-on threshold voltage of the NMOS transistor in the second switching circuit 222 meets the turn-on condition after passing through the resistor voltage divider network. The power supply V1—first voltage divider resistor R1—second voltage divider resistor R2—NMOS in the second switching circuit 222—light-emitting device LED1 form a closed path, and the light-emitting device LED1 is turned on.

[0094] When a 24V power supply voltage is input, the Zener diodes D1 in both the first and second detection control units 231 and 232 meet the breakdown voltage, and the transistors Q1 in both units are turned on. This causes the gate voltages of the NMOS transistors in the first and second switching circuits 221 to be 0V, thus turning off these two NMOS transistors. After passing through the resistor divider network, the corresponding turn-on threshold voltage of the NMOS transistor in the third switching circuit 223 meets the turn-on condition. A closed path is formed: power supply V1—first voltage divider resistor R1—second voltage divider resistor R2—third voltage divider resistor R3—NMOS transistor in the third switching circuit 223—LED1, turning on the LED1.

[0095] The aforementioned driving circuit 200, by selecting the resistance values ​​of the first voltage divider resistor R1, the second voltage divider resistor R2, and the third voltage divider resistor R3, ensures that the current flowing through the light-emitting device LED1 is similar under different input voltages, thereby guaranteeing that although the input voltage of the lamp board is different, the brightness of the lamp board is the same or similar.

[0096] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0097] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A refrigerator, characterized in that, include: Light panel, including light-emitting devices; The power input terminal is used to connect to power supply voltages of different voltage levels; A driving circuit, connected to the power input terminal and the light-emitting device, is used to drive the light-emitting device to emit light according to the power supply voltage; The driving circuit includes: Multiple resistor components, with the first and last ends of each resistor component connected sequentially, and the first end of the first resistor component connected to the power input terminal. Multiple switching circuits, the first end of each switching circuit is connected to the end of a resistor component, and the second end of each switching circuit is connected to the light-emitting device. The switching control circuit is connected to the power input terminal and also to the control terminals of each of the switching circuits other than the one connected to the last resistor assembly. The multiple switching circuits are used for time-division multiplexing, the voltage division of the control terminal of the switching circuit in the on state is greater than the on-state voltage, and the resistance value of the resistor assembly between the first terminal of the on-state switching circuit and the power input terminal matches the current voltage level of the power supply voltage.

2. The refrigerator according to claim 1, characterized in that, The switching circuit includes a switching transistor, a first resistor, and a second resistor. The first terminal of the switching transistor serves as the first terminal of the switching circuit, and the second terminal of the switching transistor serves as the second terminal of the switching circuit. The control terminal of the switching transistor is connected to the first terminal of the first resistor and the first terminal of the second resistor, respectively, serving as the control terminal of the switching circuit. The second terminal of the first resistor is connected to the first terminal of the switching transistor, and the second terminal of the second resistor is grounded. The switching transistor is used to turn on when the voltage at the control terminal reaches the turn-on voltage.

3. The refrigerator according to claim 2, characterized in that, The switching control circuit includes multiple detection control units, the number of which is one less than the number of the switching circuit. The detection terminal of each detection control unit is connected to the power input terminal, and the switching control terminal of each detection control unit is connected to the control electrode of a switching transistor. The detection and control unit is used to control the corresponding switch to turn off according to the current voltage level of the power supply voltage, so that the resistance value of the resistor component between the switch in the on state and the power input terminal matches the current voltage level.

4. The refrigerator according to claim 3, characterized in that, The detection and control unit includes a Zener diode and a transistor; the cathode of the Zener diode is connected to the power input terminal, the anode of the Zener diode is connected to the base of the transistor, the collector of the transistor is connected to the control terminal of the switching transistor, and the emitter of the transistor is grounded; the breakdown voltage of the Zener diode in each of the detection and control units corresponds to the other voltage levels besides the highest level in the power supply voltage level; The breakdown voltage of the Zener diode in each of the detection and control units is positively correlated with the resistance value of the resistor assembly between the first terminal of the corresponding switch circuit and the power input terminal.

5. The refrigerator according to claim 2, characterized in that, The switching transistor is a MOS transistor, with the drain as the first terminal, the source as the second terminal, and the gate as the control terminal.

6. The refrigerator according to claim 5, characterized in that, The driving circuit further includes a discharge unit, wherein the first end of the discharge unit and the anode of the light-emitting device are both connected to the second terminal of the switching transistor, and the second end of the discharge unit and the cathode of the light-emitting device are both grounded.

7. The refrigerator according to claim 6, characterized in that, The discharge unit includes a discharge resistor, which is connected in parallel with the light-emitting device.

8. The refrigerator according to claim 7, characterized in that, The resistance value of the bleeder resistor is equal to the resistance value of the second resistor.

9. The refrigerator according to claim 1, characterized in that, The resistance values ​​of each resistor component gradually increase according to the connection sequence.

10. The refrigerator according to claim 1, characterized in that, The light-emitting device includes a light-emitting diode, the anode of which is connected to the second terminal of each of the switching circuits, and the cathode of which is grounded.

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