Illuminating lamp brightness adjusting circuit, illuminating lamp and refrigerator

Abstract

The utility model provides an illuminating lamp brightness adjusting circuit, an illuminating lamp and a refrigerator, the illuminating lamp brightness adjusting circuit comprises at least two voltage adjusting modules, a voltage follower and a switch module, the voltage adjusting amplitudes of the voltage adjusting modules are different, and each voltage adjusting module is provided with a switch; the first end of the voltage regulation module is used for being connected with a power supply module, and the second end of the voltage regulation module is connected with the input end of the voltage follower through the switch; the output end of the voltage follower is connected with the controlled end of the switch module; the input end of the switch module is used for being connected with the power supply module, and the output end of the switch module is used for being connected with an illuminating lamp. The lighting lamp brightness adjusting circuit provided by the embodiment of the utility model is composed of the plurality of voltage adjusting modules and the switches, the voltage followers and the switch modules corresponding to the voltage adjusting modules, no software program is needed, the development period is short, and the risk of program errors does not exist.

Description

Technical Field

[0001] The utility model relates to the field of household appliances, in particular to a lighting lamp brightness adjustment circuit, a lighting lamp and a refrigerator. Background Art

[0002] As refrigerator functions become more complex and diverse, refrigerator control systems also become more complex. For example, the newly added sterilization progress lighting panel or back surface light source needs to be more brightness-adjustable to meet user needs. Usually, after the lighting panel is produced, the brightness is fixed during use or the brightness is adjusted through software control. However, lighting with fixed brightness cannot meet customer needs, and lighting with brightness controlled by software requires special software program development, which has a long development cycle and the risk of program errors. Utility Model Content

[0003] The utility model provides a lighting lamp brightness adjustment circuit, a lighting fixture and a refrigerator to solve the technical problems of a long development cycle and a program error risk in existing software control circuits. The brightness adjustment circuit composed of pure hardware can shorten the development cycle and eliminate the program error risk.

[0004] In order to solve the above technical problems, the embodiment of the utility model provides a lighting lamp brightness adjustment circuit, characterized in that it includes at least two voltage adjustment modules, a voltage follower and a switch module, the voltage adjustment amplitudes of each of the voltage adjustment modules are different, and each of the voltage adjustment modules is configured with a switch;

[0005] The first end of the voltage regulating module is used to connect to the power supply module, and the second end of the voltage regulating module is connected to the input end of the voltage follower through the switch;

[0006] The output end of the voltage follower is connected to the controlled end of the switch module;

[0007] The input end of the switch module is used to connect to the power module, and the output end of the switch module is used to connect to the lighting lamp.

[0008] As an improvement of the above solution, the voltage regulating module includes a positive-end voltage-dividing resistor and a negative-end voltage-dividing resistor;

[0009] The first end of the positive voltage-dividing resistor is connected to the first end of the voltage regulating module, and the second end of the positive voltage-dividing resistor is connected to the first end of the switch and the first end of the negative voltage-dividing resistor respectively;

[0010] The second end of the switch is connected to the input end of the voltage follower;

[0011] The second end of the negative voltage dividing resistor is used for grounding.

[0012] As an improvement of the above scheme, the voltage regulation amplitude of the voltage regulation module is the ratio of the positive end voltage dividing resistor of the voltage regulation module to the negative end voltage dividing resistor of the voltage regulation module; the larger the voltage regulation amplitude of the voltage regulation module corresponding to the switch in the closed state, the smaller the brightness of the lighting lamp.

[0013] As an improvement of the above solution, the switch module includes an NPN transistor, a first current limiting resistor and a second current limiting resistor;

[0014] The base of the NPN transistor is connected to the first end of the first current limiting resistor, the collector of the NPN transistor is used to connect to the input end of the switch module, and the emitter of the NPN transistor is connected to the first end of the second current limiting resistor;

[0015] The second end of the first current limiting resistor is connected to the controlled end of the switch module;

[0016] The second end of the second current limiting resistor is connected to the output end of the switch module.

[0017] As an improvement of the above solution, the voltage follower includes an operational amplifier and an RC buffer absorption module;

[0018] The positive input terminal of the operational amplifier is connected to the input terminal of the voltage follower, the negative input terminal of the operational amplifier is connected to the first terminal of the RC buffer absorption module, the output terminal of the operational amplifier is connected to the output terminal of the voltage follower, the positive power input terminal of the operational amplifier is used to connect to the power module, and the negative power input terminal of the operational amplifier is used to be grounded;

[0019] The second end of the RC buffer absorption module is connected to the output end of the voltage follower.

[0020] As an improvement of the above solution, the RC buffer absorption module includes a feedback resistor and an absorption capacitor;

[0021] The first end of the feedback resistor is connected to the inverting input end of the operational amplifier, and the second end of the feedback resistor is connected to the output end of the operational amplifier;

[0022] The first end of the feedback resistor is connected to the inverting input end of the operational amplifier, and the second end of the feedback resistor is connected to the output end of the operational amplifier.

[0023] An embodiment of the utility model further provides a lighting fixture, comprising a lighting lamp and a lighting lamp brightness adjustment circuit as described in any of the above embodiments.

[0024] The embodiment of the utility model further provides a refrigerator, comprising a refrigerator body and the lighting fixture as described in the above embodiment.

[0025] Compared with the prior art, the beneficial effect of the embodiment of the utility model is that the embodiment of the utility model provides a lighting lamp brightness adjustment circuit, a lighting fixture and a refrigerator, and the lighting lamp brightness adjustment circuit includes: at least two voltage adjustment modules, a voltage follower and a switch module, the voltage adjustment amplitudes of each of the voltage adjustment modules are different, and each of the voltage adjustment modules is configured with a switch; the first end of the voltage adjustment module is used to connect the power module, and the second end of the voltage adjustment module is connected to the input end of the voltage follower through the switch; the output end of the voltage follower is connected to the controlled end of the switch module; the input end of the switch module is used to connect the power module, and the output end of the switch module is used to connect the lighting lamp, and the voltage adjustment module corresponding to the closed switch adjusts the voltage input by the power module, and then outputs the adjusted voltage signal to the voltage follower, and sends a signal to the controlled end of the switch module via the voltage follower, so as to adjust the voltage of the output end of the switch module, thereby realizing the control of the brightness of the lighting lamp; the lighting lamp brightness adjustment circuit of this embodiment is composed of a plurality of voltage adjustment modules and their corresponding switches, voltage followers and switch modules, and does not require the participation of software programs, has a short development cycle and does not have the risk of program errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a lighting lamp brightness adjustment circuit provided by a preferred embodiment of the utility model;

[0027] Figure 2 This is a schematic diagram of a knob switch provided by a preferred embodiment of the utility model;

[0028] Figure 3 It is a structural schematic diagram of a voltage regulation module provided by a preferred embodiment of the utility model;

[0029] Figure 4 It is a structural schematic diagram of a switch module provided by a preferred embodiment of the utility model;

[0030] Figure 5 It is a structural schematic diagram of a voltage follower provided by a preferred embodiment of the utility model;

[0031] Figure 6 It is a structural schematic diagram of an RC buffer absorption module provided by a preferred embodiment of the utility model;

[0032] Figure 7 It is a structural schematic diagram of a lighting lamp brightness adjustment circuit provided by a preferred embodiment of the utility model;

[0033] Figure 8 It is a structural schematic diagram of a lighting fixture provided by a preferred embodiment of the utility model;

[0034] Fig. 9 It is a three-dimensional diagram of a refrigerator body provided by a preferred embodiment of the utility model;

[0035] Fig.10 It is a three-dimensional diagram of a refrigerator door provided by a preferred embodiment of the utility model;

[0036] Fig.11 It is a structural schematic diagram of a communication system provided by a preferred embodiment of the utility model;

[0037] Among them; 100, box body, 200, door body, 210, door body shell, 220, door body liner, 230, upper end cover, 240, lower end cover; 101, refrigerator; 201, client; 301, router; 401, cloud server; 1, power module; 2, voltage regulation module; 21, positive end voltage divider resistor; 22, negative end voltage divider resistor; 3, switch; 4, voltage follower; 41, RC cache absorption module; 5, switch module; 6, lighting; 10, lighting brightness adjustment circuit; U1, operational amplifier; R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; R6, sixth resistor; R7, seventh resistor; R8, eighth resistor; R9, ninth resistor; R10, tenth resistor; R11, eleventh resistor; R12, twelfth resistor;

[0038] R13, the thirteenth resistor; R14, the fourteenth resistor; R15, the fifteenth resistor; R16, the sixteenth resistor; R17, the feedback resistor; R18, the second current limiting resistor; R19, the first current limiting resistor; S1, the first switch; S2, the second switch; S3, the third switch; S4, the fourth switch; S5, the fifth switch; S6, the sixth switch; S7, the seventh switch; S8, the eighth switch; Q1, the NPN transistor. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0040] See also Figure 1The preferred embodiment of the utility model provides a lighting lamp brightness adjustment circuit, comprising at least two voltage adjustment modules 2, a voltage follower 4 and a switch 3 module, wherein the voltage adjustment amplitudes of the voltage adjustment modules 2 are different, and each of the voltage adjustment modules 2 is configured with a switch 3;

[0041] The first end of the voltage regulating module 2 is used to connect to the power module 1, and the second end of the voltage regulating module 2 is connected to the input end of the voltage follower 4 through the switch 3;

[0042] The output end of the voltage follower 4 is connected to the controlled end of the switch 3 module;

[0043] The input end of the switch 3 module is used to connect to the power module 1 , and the output end of the switch 3 module is used to connect to the lighting lamp 6 .

[0044] It is worth noting that in the embodiment of the utility model, the switch 3 refers to an electronic component that can open a circuit, interrupt a current, or flow it to other circuits. The most common switch 3 is an electromechanical device operated by a person, which has at least one electronic contact. When the switch 3 is closed, the electronic contact is conductive, allowing current to flow through. When the switch 3 is open, the electronic contact is not conductive, and current is not allowed to flow through. The switch 3 can be a key switch 3 or a knob switch 3. The switch 3 module is a device that determines whether it is conductive or not by the voltage relationship of each end, such as a triode or a metal oxide semiconductor field effect tube. The voltage at its output end is associated with the voltage at the controlled end, and the voltage at the output end can be controlled by controlling the voltage at the controlled end.

[0045] Specifically, the output end of the power supply module 1 is respectively connected to the input end of the switch 3 module and the first end of each voltage regulating module 2. The voltage regulating amplitude of each voltage regulating module 2 is different. The first end of the voltage regulating module 2 is used as the input end to receive the power signal V1 provided by the power supply module 1. The second end of the voltage regulating module 2 is the output end, which is used to send the power signal after voltage regulation to the switch 3. When the switch 3 is closed, the power signal after voltage regulation is input into the voltage follower 4 for processing, and then transmitted to the controlled end of the switch 3 module to control the voltage at the output end of the switch 3 module, that is, to control the voltage of the lighting lamp 6, thereby realizing the adjustment of the brightness of the lighting lamp 6. It can be understood that at the same time, at most only one switch 3 is in a closed state, and the other switches 3 are in an open state. The voltage regulating module 2 corresponding to the switch 3 in the closed state adjusts the signal transmitted to the controlled end of the switch 3 module. When all switches 3 are in an open state, the lighting lamp 6 is in an off state. For example, see Figure 2The schematic diagram of the knob switch 3 shown in the figure, if the switch 3 is a knob switch 3, the specific switch 3 is controlled to be closed by rotating the knob, and the specific implementation method can refer to the prior art.

[0046] Compared with the prior art, the lighting lamp brightness adjustment circuit provided by the embodiment of the utility model includes at least two voltage adjustment modules 2, a voltage follower 4 and a switch 3 module. The voltage adjustment amplitudes of the voltage adjustment modules 2 are different, and each of the voltage adjustment modules 2 is configured with a switch 3; the first end of the voltage adjustment module 2 is used to connect to the power module 1, and the second end of the voltage adjustment module 2 is connected to the input end of the voltage follower 4 through the switch 3; the output end of the voltage follower 4 is connected to the controlled end of the switch 3 module; the input end of the switch 3 module is used to connect to the power module 1, and the output end of the switch 3 module is used to connect to the lighting lamp 6, which solves the technical problems of the long development cycle and the risk of program errors of the existing software control circuit, and can achieve the effect of shortening the development cycle and eliminating the risk of program errors through a brightness adjustment circuit composed of pure hardware.

[0047] In one embodiment, the voltage regulating module 2 includes a positive voltage dividing resistor 21 and a negative voltage dividing resistor 22; the first end of the positive voltage dividing resistor 21 is connected to the first end of the voltage regulating module 2, and the second end of the positive voltage dividing resistor 21 is respectively connected to the first end of the switch 3 and the first end of the negative voltage dividing resistor 22; the second end of the switch 3 is connected to the input end of the voltage follower 4; the second end of the negative voltage dividing resistor 22 is used for grounding.

[0048] In one embodiment, the voltage regulation amplitude of the voltage regulation module 2 is the ratio of the positive end voltage dividing resistor 21 of the voltage regulation module 2 to the negative end voltage dividing resistor 22 of the voltage regulation module 2; the larger the voltage regulation amplitude of the voltage regulation module 2 corresponding to the switch 3 in the closed state, the smaller the brightness of the lighting lamp 6.

[0049] See also Figure 3 , Figure 3: This is a schematic diagram of the structure of a voltage regulating module 2 provided by an embodiment of the utility model. The voltage regulating module 2 is mainly composed of two resistors. The power supply voltage of the power supply module 1 is input into the voltage regulating module 2, and the positive voltage-dividing resistor 21 and the negative voltage-dividing resistor 22 are used for voltage division. The signal after voltage division is transmitted to the input end of the voltage follower 4 through the closed switch 3. The voltage regulation amplitude of the voltage regulating module 2 is determined by the ratio of the positive voltage-dividing resistor 21 and the negative voltage-dividing resistor 22. When the ratio of the positive voltage-dividing resistor 21 and the negative voltage-dividing resistor 22 is larger, the voltage across the positive voltage-dividing resistor 21 is larger, the voltage across the negative voltage-dividing resistor 22 is smaller, and the voltage transmitted to the input end of the voltage follower 4 is smaller, which leads to a smaller voltage received by the controlled end of the switch 3 module, a smaller voltage provided to the lighting lamp 6, and a smaller brightness of the lighting lamp 6. On the contrary, when the ratio of the positive voltage-dividing resistor 21 and the negative voltage-dividing resistor 22 is smaller, the brightness of the lighting lamp 6 is greater.

[0050] In one embodiment, the switch 3 module includes an NPN transistor Q1, a first current limiting resistor R19 and a second current limiting resistor R18;

[0051] The base of the NPN transistor Q1 is connected to the first end of the first current limiting resistor R19, the collector of the NPN transistor Q1 is used to connect to the input end of the switch 3 module, and the emitter of the NPN transistor Q1 is connected to the first end of the second current limiting resistor R18;

[0052] The second end of the first current limiting resistor R19 is connected to the controlled end of the switch 3 module;

[0053] The second end of the second current limiting resistor R18 is connected to the output end of the switch 3 module.

[0054] Specifically, see Figure 4 , Figure 4 It is a structural schematic diagram of a switch 3 module provided by an embodiment of the utility model. The switch 3 module is mainly composed of an NPN transistor Q1, a first current limiting resistor R19 and a second current limiting resistor R18. The first current limiting resistor R19 is connected to the base side of the NPN transistor Q1, and is used to limit the current input to the NPN transistor Q1 to prevent the NPN transistor Q1 from being seriously heated due to excessive base current, so as to burn out; the second current limiting resistor R18 is connected to the lighting lamp 6, and is used to limit the current flowing into the lighting lamp 6 to protect the lighting lamp 6. The voltage signal output by the output end of the voltage follower 4 flows to the base of the NPN transistor Q1 via the first current limiting resistor R19, and controls the voltage of the emitter of the NPN transistor Q1, thereby realizing the brightness adjustment of the lighting lamp 6.

[0055] In one embodiment, the voltage follower 4 includes an operational amplifier U1 and an RC buffer absorption module; the positive input terminal of the operational amplifier U1 is connected to the input terminal of the voltage follower 4, the negative input terminal of the operational amplifier U1 is connected to the first terminal of the RC buffer absorption module, the output terminal of the operational amplifier U1 is connected to the output terminal of the voltage follower 4, the positive power input terminal of the operational amplifier U1 is used to connect to the power module 1, and the negative power input terminal of the operational amplifier U1 is used to be grounded; the second terminal of the RC buffer absorption module is connected to the output terminal of the voltage follower 4.

[0056] Specifically, see Figure 5 , Figure 5 1 is a schematic diagram of the structure of a voltage follower 4 provided by an embodiment of the utility model. The voltage follower 4 is mainly composed of an operational amplifier U1 and an RC buffer absorption module. The voltage follower 4 (also called a buffer amplifier, a unity gain amplifier or an isolation amplifier) ​​is an operational amplifier U1 circuit, whose output voltage "follows" the input voltage, provides a buffering effect, so that the signal at the controlled end of the input switch 3 module is stable, and thus the brightness of the lighting lamp 6 is stable.

[0057] In one embodiment, the RC buffer absorption module includes a feedback resistor R17 and an absorption capacitor;

[0058] A first end of the feedback resistor R17 is connected to the inverting input end of the operational amplifier U1, and a second end of the feedback resistor R17 is connected to the output end of the operational amplifier U1;

[0059] A first end of the feedback resistor R17 is connected to the inverting input end of the operational amplifier U1 , and a second end of the feedback resistor R17 is connected to the output end of the operational amplifier U1 .

[0060] Specifically, see Figure 6 , Figure 6 This is a schematic diagram of the structure of an RC buffer absorption module provided by an embodiment of the utility model. The RC buffer absorption module is mainly composed of a feedback resistor R17 and an absorption capacitor. The resistance range of the feedback resistor R17 is 1KΩ (kilo-ohm) to 1MΩ (mega-ohm), and the value range of the absorption capacitor is 1nF (nanofarad) to 1μF (microfarad), and its specific value is set according to the actual application.

[0061] In order to make the lighting lamp brightness adjustment circuit of the utility model embodiment clearer, a specific example is used below to illustrate. Figure 7 , Figure 7It is a structural diagram of a lighting lamp brightness adjustment circuit provided by an embodiment of the utility model. The lighting lamp brightness adjustment circuit includes eight voltage adjustment modules 2, a voltage follower 4 and a switch 3 module. Each voltage adjustment module 2 is configured with a switch 3, and there are eight switches 3 in total; the switch 3 module is composed of an NPN transistor Q1, a first current limiting resistor R19 and a second current limiting resistor R18. The first resistor R1 to the eighth resistor R8 are all positive end voltage dividing resistors 21, and the ninth resistor R9 to the sixteenth resistor R16 are negative end voltage dividing resistors 22. The first resistor R1 and the ninth resistor R9 form a voltage regulating module, which corresponds to the first switch S1; the second resistor R2 and the tenth resistor R10 form a voltage regulating module, which corresponds to the second switch S2; the third resistor R3 and the eleventh resistor R11 form a voltage regulating module, which corresponds to the third switch S3; the fourth resistor R4 and the twelfth resistor R12 form a voltage regulating module, which corresponds to the fourth switch S4; the fifth resistor R5 and the thirteenth resistor R13 form a voltage regulating module, which corresponds to the fifth switch S5; the sixth resistor R6 and the fourteenth resistor R14 form a voltage regulating module, which corresponds to the sixth switch S6; the seventh resistor R7 and the fifteenth resistor R15 form a voltage regulating module, which corresponds to the seventh switch S7; the eighth resistor R8 and the sixteenth resistor R16 form a voltage regulating module, which corresponds to the eighth switch S8.

[0062] Its working principle is as follows: when the first switch S13 is turned on, the voltage-divided value of the first resistor R1 and the ninth resistor R9 is connected to the positive input terminal (positive input terminal) of the operational amplifier U1. Since the feedback resistor R17 and the absorption capacitor are connected in parallel to the negative input terminal (negative input terminal) and the output terminal of the operational amplifier U1, a voltage follower 4 is formed. At this time, the output of the operational amplifier U1 is also the previous voltage-divided value. The voltage forms a path through the first current-limiting resistor R19, the second current-limiting resistor R18 and LED1 (here, the LED lamp is used as the lighting lamp 6, and the type of the lighting lamp 6 is not limited to this and can be set according to actual conditions), so that the NPN transistor Q1 is turned on. At this time, the voltage at the left end of the second current-limiting resistor R18 is the previous voltage-divided value minus the emitter junction voltage (about 0.7V). The voltage is applied to the second current-limiting resistor R18 and LED1 to form a current, the lamp bead is lit, and the lamp board is lit accordingly. When other switches 3 are closed, the working principle is the same as the above, and no further description is given here.

[0063] See also Figure 8 , Figure 81 is a schematic diagram of the structure of a lighting fixture provided by an embodiment of the utility model, and the lighting fixture includes a lighting lamp 6 and a lighting lamp brightness adjustment circuit 10 as described in any of the above embodiments. Specifically, the lighting lamp brightness adjustment circuit 10 is used to supply power to the lighting lamp 6, and the brightness of the lighting lamp 6 is controlled by adjusting the output voltage of the lighting lamp brightness adjustment circuit 10. In the embodiment of the utility model, the specific working principle of the lighting lamp brightness adjustment circuit 10 is the same as the working principle of the lighting lamp brightness adjustment circuit described in any of the above embodiments, and will not be described in detail here.

[0064] An embodiment of the utility model further provides a refrigerator, comprising a refrigerator body and a lighting fixture as described in any of the above embodiments.

[0065] Reference Fig. 9 The refrigerator body shown in the figure is approximately in the shape of a rectangular parallelepiped, and includes a box body 100 defining a storage space and a plurality of door bodies 200 disposed at the opening of the box body 100, wherein the refrigerator body 100 is substantially in the shape of a rectangular parallelepiped, and includes a box body 100 defining a storage space and a plurality of door bodies 200 disposed at the opening of the box body 100, wherein the door body 200 is substantially in the shape of Fig.10 As shown, the door body 200 includes a door body shell 210 located on the outside of the box body 100, a door body liner 220 located on the inside of the box body 100, an upper end cover 230, a lower end cover 240, and an insulating layer located between the door body shell 210, the door body liner 220, the upper end cover 230, and the lower end cover 240; usually, the insulating layer is filled with foam. The box body 100 is provided with a chamber, wherein the chamber includes a component storage chamber for placing components in the refrigerator, such as a compressor, etc., and also includes a storage space for storing food, medicine, etc. Among them, the storage space can be divided into a plurality of storage rooms, and the storage rooms can be configured as a refrigeration room, a freezing room, and a temperature-changing room (also called a fresh-keeping room) according to different uses. Each storage room corresponds to one or more door bodies. In order to facilitate users to check the items in the storage room, a lighting lamp 6 is provided in the storage room. For further reference, Fig.11 , the refrigerator 101 establishes a data connection with the client 201 through the router 301 or the cloud server 401. When the refrigerator 101 and the client 201 communicate through the router 301, the refrigerator 101 and the client 201 are close to each other, and the user can view the operation status of the refrigerator placed in the kitchen or the storage status of food in the living room or room. When the refrigerator 101 and the client 201 communicate through the cloud server 401, the refrigerator 101 and the client 201 are far apart, and the user can interact with the refrigerator 101 through the APP installed in the client 201, and can also realize remote control of the refrigerator 101, such as controlling the switch 3 in the lighting brightness adjustment circuit to turn off or on.

[0066] Compared with the prior art, the beneficial effect of the embodiment of the utility model is that the embodiment of the utility model provides a lighting brightness adjustment circuit, a lighting fixture and a refrigerator, and the lighting brightness adjustment circuit includes at least two voltage adjustment modules 2, a voltage follower 4 and a switch 3 module, and the voltage adjustment amplitudes of each of the voltage adjustment modules 2 are different, and each of the voltage adjustment modules 2 is configured with a switch 3; the first end of the voltage adjustment module 2 is used to connect to the power module 1, and the second end of the voltage adjustment module 2 is connected to the input end of the voltage follower 4 through the switch 3; the output end of the voltage follower 4 is connected to the controlled end of the switch 3 module; the switch The input end of the switch 3 module is used to connect the power module 1, and the output end of the switch 3 module is used to connect the lighting lamp 6. The voltage regulating module 2 corresponding to the closed switch 3 regulates the voltage input to the power module 1, and then outputs the regulated voltage signal to the voltage follower 4, and sends a signal to the controlled end of the switch 3 module via the voltage follower 4, so as to adjust the voltage at the output end of the switch 3 module, thereby realizing the control of the brightness of the lighting lamp 6; the lighting lamp brightness adjustment circuit of this embodiment is composed of multiple voltage regulating modules 2 and their corresponding switches 3, voltage followers 4 and switch 3 modules, and does not require the participation of software programs, has a short development cycle and does not have the risk of program errors.

[0067] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the protection scope of the present invention.

Claims

1. A lighting lamp brightness adjustment circuit, characterized in that: It comprises at least two voltage regulating modules, a voltage follower and a switch module, wherein the voltage regulating amplitudes of the voltage regulating modules are different, and each of the voltage regulating modules is configured with a switch; The first end of the voltage regulating module is used to connect to the power supply module, and the second end of the voltage regulating module is connected to the input end of the voltage follower through the switch; The output end of the voltage follower is connected to the controlled end of the switch module; The input end of the switch module is used to connect to the power module, and the output end of the switch module is used to connect to the lighting lamp.

2. The lighting lamp brightness adjustment circuit according to claim 1, characterized in that: The voltage regulation module includes a positive-end voltage-dividing resistor and a negative-end voltage-dividing resistor; The first end of the positive voltage-dividing resistor is connected to the first end of the voltage regulating module, and the second end of the positive voltage-dividing resistor is connected to the first end of the switch and the first end of the negative voltage-dividing resistor respectively; The second end of the switch is connected to the input end of the voltage follower; The second end of the negative voltage dividing resistor is used for grounding.

3. The lighting lamp brightness adjustment circuit according to claim 2, characterized in that: The voltage regulation amplitude of the voltage regulation module is the ratio of the positive-end voltage-dividing resistor of the voltage regulation module to the negative-end voltage-dividing resistor of the voltage regulation module; The larger the voltage regulation amplitude of the voltage regulation module corresponding to the switch in the closed state is, the smaller the brightness of the lighting lamp is.

4. The lighting lamp brightness adjustment circuit according to claim 1, characterized in that: The switch module includes an NPN transistor, a first current limiting resistor and a second current limiting resistor; The base of the NPN transistor is connected to the first end of the first current limiting resistor, the collector of the NPN transistor is used to connect to the input end of the switch module, and the emitter of the NPN transistor is connected to the first end of the second current limiting resistor; The second end of the first current limiting resistor is connected to the controlled end of the switch module; The second end of the second current limiting resistor is connected to the output end of the switch module.

5. The lighting lamp brightness adjustment circuit according to claim 1, characterized in that: The voltage follower includes an operational amplifier and an RC buffer absorption module; The positive input terminal of the operational amplifier is connected to the input terminal of the voltage follower, the negative input terminal of the operational amplifier is connected to the first terminal of the RC buffer absorption module, the output terminal of the operational amplifier is connected to the output terminal of the voltage follower, the positive power input terminal of the operational amplifier is used to connect to the power module, and the negative power input terminal of the operational amplifier is used to be grounded; The second end of the RC buffer absorption module is connected to the output end of the voltage follower.

6. The lighting lamp brightness adjustment circuit according to claim 5, characterized in that: The RC buffer absorption module includes a feedback resistor and an absorption capacitor; The first end of the feedback resistor is connected to the inverting input end of the operational amplifier, and the second end of the feedback resistor is connected to the output end of the operational amplifier.

7. A lighting fixture, characterized in that: The invention comprises a lighting lamp and a lighting lamp brightness adjustment circuit as claimed in any one of claims 1 to 6.

8. A refrigerator, characterized in that: The invention comprises a refrigerator body and the lighting fixture as claimed in claim 7.

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