LED lighting circuit and lighting circuit

Abstract

The present application relates to an LED lighting circuit and a lighting circuit. The LED lighting circuit comprises: a power input terminal and at least one lighting unit, the first terminal of each lighting unit is electrically connected to the power input terminal, and the power input terminal is used to be electrically connected to the output terminal of the previous LED lighting circuit; the driving circuit comprises at least one driving unit corresponding to at least one lighting unit, and each driving unit comprises a first voltage divider unit and a current control subcircuit; the first terminal of the first voltage divider unit is electrically connected to the power input terminal, and the resistance value of the first voltage divider unit is the same as the resistance value of the corresponding lighting unit; the current control subcircuit is used to control the first current flowing through the corresponding lighting unit and the second current flowing through the corresponding first voltage divider unit, and the sum of the first current and the second current remains unchanged; the third terminal of the current control subcircuit is used to be electrically connected to the power input terminal of the next LED lighting circuit. The LED lighting circuit and the lighting circuit of the present application have the advantage of constant output current.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to an LED lighting circuit and a lighting circuit. Background Art

[0002] As a rapidly developing emerging industry, LED display has become an important way of information dissemination and has been widely used in advertising, stage background, traffic guidance and other fields. As the demand for LED display increases, LED circuits are also constantly updated. When LED emits light, the current passing through the LED needs to be adjusted, and in some scenarios, the overall current of the LED lighting circuit needs to remain unchanged.

[0003] When the existing circuit is in use, if the LED is emitting light, stops emitting light, or the brightness changes, the current of the entire circuit will change, and the stability of the current is low. Summary of the invention

[0004] The purpose of this application is to solve at least one of the above-mentioned technical defects, and the following technical solution is specially proposed.

[0005] In order to solve the above technical problems, in a first aspect, the present application provides an LED lighting circuit, comprising:

[0006] A power input terminal and at least one lighting unit, wherein a first terminal of each lighting unit is electrically connected to the power input terminal, and the power input terminal is used to be electrically connected to an output terminal or a power supply of a previous LED lighting circuit;

[0007] A driving circuit, comprising at least one driving unit corresponding to at least one of the lighting units, each of the driving units comprising a first voltage dividing unit and a current control subcircuit;

[0008] The first end of the first voltage dividing unit is electrically connected to the power input end, and the resistance value of the first voltage dividing unit is the same as the resistance value of the corresponding lighting unit;

[0009] A current control subcircuit, wherein the first end and the second end are electrically connected to the second end of the corresponding lighting unit and the second end of the corresponding first voltage divider unit respectively, and is used to control a first current flowing through the corresponding lighting unit and a second current flowing through the corresponding first voltage divider unit so that the sum of the first current and the second current remains unchanged; the third end of the current control subcircuit serves as the output end of the LED lighting circuit, and is used to be electrically connected to the power input end of the next LED lighting circuit or to be grounded.

[0010] Optionally, the current control subcircuit includes:

[0011] At least one first switch unit; one end of each of the first switch units is electrically connected to the second end of the corresponding lighting unit, and is used to control the on and off of the first switch unit according to an external first control signal;

[0012] At least one second switch unit, each of the second switch units has one end electrically connected to the second end of the corresponding first voltage divider unit, and the other end electrically connected to the other end of the corresponding first switch unit, and is used to control the electrical on-off state of the second switch unit according to an external second control signal, and the electrical on-off state of each second switch unit is opposite to the electrical on-off state of the corresponding first switch unit.

[0013] Optionally, a first end of each first switch unit is electrically connected to a second end of the corresponding lighting unit, and a second end is electrically connected to an external first control circuit, and is used to control the electrical on-off state between the first end and the third end of the first switch unit according to a first control signal of the first control circuit, and the electrical on-off state of any first switch unit is the same as or different from the electrical on-off state of other first switch units;

[0014] Each of the second switch units has a first end electrically connected to the second end of the corresponding first voltage divider unit, a second end for electrically connecting to an external second control section, and a third end electrically connected to the third end of the corresponding first switch unit, for controlling the electrical on / off state between the first end and the third end of the second switch unit according to the second control signal of the second control circuit.

[0015] Optionally, the current control subcircuit further includes:

[0016] The number of current limiting sub-circuits is consistent with that of the first switch units, the current limiting sub-circuits correspond one-to-one to the first switch units, the first end of each current limiting sub-circuit is electrically connected to the third end of the first switch unit corresponding to the current limiting sub-circuit, and the second end of each current limiting sub-circuit is an output end.

[0017] Optionally, each of the current limiting sub-circuits comprises:

[0018] At least one current limiting unit, the first end of the current limiting unit of each current limiting sub-circuit is electrically connected to the third end of the first switch unit corresponding to the current limiting sub-circuit, the second end of the current limiting unit of each current limiting sub-circuit is an output end, and the third end of the current limiting unit of each current limiting sub-circuit is used to be electrically connected to an external third control circuit, and the current limiting unit is used to control the electrical conduction between the first end and the second end of the current limiting unit according to a third control signal received from the third control circuit, and when the first end and the second end of the current limiting unit are electrically conductive, the current allowed to pass between the first end and the second end of the current limiting unit is a preset value.

[0019] Optionally, the current limiting unit is a current limiting switch element, the first end of the current limiting unit is the first end of the current limiting switch unit; the second end of the current limiting unit is the second end of the current limiting switch unit, and the third end of the current limiting unit is the control end of the current limiting switch element.

[0020] Optionally, the LED lighting circuit further includes:

[0021] A clamping circuit, wherein a first end of the clamping circuit is electrically connected to a first end of the lighting unit, and a second end of the clamping circuit is used to be electrically connected to a power input end of a next LED lighting circuit or to be grounded.

[0022] Optionally, the clamping circuit comprises:

[0023] a second voltage dividing unit, wherein a first end of the second voltage dividing unit is electrically connected to a first end of the lighting unit;

[0024] A diode, wherein the cathode of the diode is electrically connected to the second end of the second voltage dividing unit, and the anode of the diode is used to be electrically connected to the power input end of the next LED lighting circuit or to be grounded.

[0025] Optionally, the first switch unit is a first MOS tube, the first end of the first switch unit is the first end of the first MOS tube, the second end of the first switch unit is the control end of the first MOS tube, and the third end of the first switch unit is the second end of the first MOS tube;

[0026] The second switch unit is a second MOS tube, the first end of the second switch unit is the first end of the second MOS tube, the second end of the second switch unit is the control end of the second MOS tube, and the third end of the second switch unit is the second end of the second MOS tube.

[0027] In a second aspect, the present application further provides a lighting circuit, comprising at least two of the above-mentioned LED lighting circuits connected in series.

[0028] In the technical solution provided by the present application, the resistance value of the first voltage divider unit is the same as the resistance value of the corresponding lighting unit. When the voltage is the same, the current that can pass through the first voltage divider unit and the lighting unit is the same. The current control subcircuit can better control the current so that the sum of the first current and the second current remains unchanged, thereby making the overall current flowing through the LED lighting circuit basically constant, and greatly enhancing the stability of the current flowing through each LED lighting circuit when at least two LED lighting circuits are connected in series. Moreover, since the second current can be adjusted so that the change in the second current can compensate for the change in the first current by a substantially equal amount, even if the first current flowing through the lighting unit is adjusted, that is, the brightness of the lighting power supply is adjusted, the overall current condition of the LED lighting circuit will not be affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of an LED lighting circuit provided in an embodiment of the present application.

[0030] Figure 2 A more specific structural schematic diagram of the LED lighting circuit provided in the embodiment of the present application.

[0031] Figure 3 A schematic diagram of the structure of a specific circuit of the LED lighting circuit provided in an embodiment of the present application.

[0032] Figure 4 A schematic diagram of the structure of another LED lighting circuit provided in an embodiment of the present application.

[0033] Figure 5 A schematic diagram of the structure of a lighting circuit provided in an embodiment of the present application.

[0034] Reference numerals:

[0035] 10-LED lighting circuit;

[0036] 11-power input terminal; L1-lighting unit;

[0037] 12-driving unit; R1-first voltage dividing unit; 121-current control subcircuit; Q1-first switch unit; Q2-second switch unit; 1211-current limiting subcircuit; Q3-current limiting unit;

[0038] 13-output terminal; 14-clamping circuit; R2-second voltage dividing unit; D1-diode. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] See also Figure 1 and Figure 2 The embodiment of the present application provides an LED (Light Emitting Diode) lighting circuit 10. The LED lighting circuit 10 is used for lighting. The LED lighting circuit 10 can be specifically applied to the fields of advertising, stage background, traffic guidance, etc. The LED lighting circuit 10 can be used alone, or connected in series or in parallel. The LED circuit of the present application has the advantages of basically constant output current and adjustable brightness.

[0041] An LED lighting circuit 10 provided in an embodiment of the present application includes: a power input terminal 11, at least one lighting unit L1 and a driving circuit.

[0042] The first end of each lighting unit L1 is electrically connected to the power input end 11 , and the power input end 11 is used to be electrically connected to the output end 13 or the power supply of the previous LED lighting circuit 10 .

[0043] The driving circuit includes at least one driving unit 12 corresponding to at least one lighting unit L1 , and each driving unit 12 includes a first voltage dividing unit R1 and a current control subcircuit 121 .

[0044] The first end of the first voltage dividing unit R1 is electrically connected to the power input end 11 , and the resistance value of the first voltage dividing unit R1 is the same as the resistance value of the corresponding lighting unit L1 .

[0045] The first end of the current control subcircuit 121 is electrically connected to the second end of the corresponding lighting unit L1, and the second end of the current control subcircuit 121 is electrically connected to the second end of the corresponding first voltage divider unit R1. The current control subcircuit 121 is used to control the first current flowing through the corresponding lighting unit L1 and the second current flowing through the corresponding first voltage divider unit R1, so that the sum of the first current and the second current remains unchanged; the third end of the current control subcircuit 121 serves as the output end 13 of the LED lighting circuit 10, and the third end of the current control subcircuit 121 is used to be electrically connected to the power input end 11 of the next LED lighting circuit 10 or to be grounded.

[0046] In the LED lighting circuit 10 of the embodiment of the present application, the resistance value of the first voltage divider unit R1 is the same as the resistance value of the corresponding lighting unit L1. When the voltage is the same, the first voltage divider unit R1 and the lighting unit L1 can pass the same current. The current control subcircuit 121 can better control the current so that the sum of the first current and the second current remains unchanged, thereby making the overall current flowing through the LED lighting circuit basically constant, and greatly enhancing the stability of the current flowing through each LED lighting circuit when at least two LED lighting circuits are connected in series. Moreover, since the second current can be adjusted, the change in the second current can compensate for the change in the first current by an essentially equal amount. Therefore, even if the first current flowing through the lighting unit is adjusted, that is, the brightness of the lighting power supply is adjusted, the overall current condition of the LED lighting circuit will not be affected.

[0047] Optionally, the power input terminal 11 is used as a power input. The power input terminal 11 can be a node, and an external power supply supplies power to other circuits or components of the LED lighting circuit 10 through the power input terminal 11. For example, when multiple LED lighting circuits 10 are connected in series, the power input terminal 11 of one LED lighting circuit 10 can be electrically connected to the output terminal 13 of the previous LED lighting circuit 10, and the power input terminal 11 of the first LED lighting circuit 10 can be electrically connected to an external power supply.

[0048] The lighting unit L1 is used to emit light. There is no limitation on the color of the light emitted by the lighting unit L1, and different lighting units L1 may emit different colors, such as the light emitted by the lighting unit L1 may be red, green or blue, etc. The lighting unit L1 may be an LED, a lamp bead, etc., as long as it can emit light. There is no limitation on the number of lighting units L1, and it may be one or more, such as two, three or four, etc. When the lighting unit L1 includes a plurality of lighting units, the first end of each lighting unit L1 is electrically connected to the power input terminal 11, that is, the lighting units L1 are connected in parallel. In the present application, three lighting units L1 are used for illustration, and the lights emitted by the three lighting units L1 are red, green and blue, respectively. By adjusting the brightness of the lights emitted by the three lighting units L1 respectively, the three colors corresponding to the three lighting units L1 can be matched by the intensity of the light, so as to adjust the color of the light emitted by the entire LED lighting circuit 10.

[0049] Optionally, the driving circuit may be an LED driving chip, and the driving circuit may control one or more lighting units L1 to emit light.

[0050] The number of the driving units 12 is consistent with the number of the lighting units L1, and each driving unit 12 controls the brightness of one lighting unit L1. For example, when there are three lighting units L1, there are also three driving units 12. In the same LED lighting circuit 10, a circuit consisting of one lighting unit L1 and a corresponding driving unit 12 is connected in parallel with a circuit consisting of another lighting unit L1 and a corresponding driving unit 12.

[0051] The first voltage divider unit R1 is used to make the current that can pass through the first voltage divider unit R1 consistent with the current of the lighting unit L1 when the voltage is consistent with the voltage of the lighting unit L1. The first voltage divider unit R1 can be one or more components, such as the first voltage divider unit R1 is a resistor, the resistance of the resistor is the same as the resistance of the lighting unit L1; the first voltage divider unit R1 can also be a plurality of components connected in series or in parallel, and the equivalent resistance of the plurality of components connected in series or in parallel is the same as the resistance of the corresponding lighting unit L1.

[0052] Optionally, see Figure 3 The current control subcircuit 121 includes at least one first switch unit Q1 and at least one second switch unit Q2 with the same number as the first switch unit Q1. Each first switch unit Q1 has one end electrically connected to the second end of the corresponding lighting unit L1, and is used to control the on and off of the first switch unit according to an external first control signal. Each second switch unit Q2 has one end electrically connected to the second end of the corresponding first voltage divider unit R1, and the other end electrically connected to the other end of the corresponding first switch unit Q1, and is used to control the electrical on and off state of the second switch unit Q2 according to an external second control signal, and the electrical on and off state of each second switch unit Q2 is opposite to the electrical on and off state of the corresponding first switch unit Q1.

[0053] Specifically, the first end of each first switch unit Q1 is electrically connected to the second end of the corresponding lighting unit L1, and the second end of each first switch unit Q1 is used to be electrically connected to an external first control circuit, and is used to control the electrical connection and disconnection between the first end and the third end of the first switch unit Q1 according to a first control signal of the first control circuit; each second switch unit Q2 corresponds to a first switch unit Q1, and the first end of each second switch unit Q2 is electrically connected to the second end of the corresponding first voltage dividing unit R1, and the second end of each second switch unit Q2 is used to be electrically connected to an external second control section, and the third end of each second switch unit Q2 is electrically connected to the third end of the corresponding first switch unit Q1, and each second switch unit Q2 is used to control the electrical connection and disconnection between the first end and the third end of the second switch unit Q2 according to a second control signal of the external second control circuit. Wherein, the electrical on-off state of any first switch unit Q1 can be the same as or different from the electrical on-off state of other first switch units Q1.

[0054] The number of the first switch unit Q1 is not limited, and the first switch unit Q1 can be one or more. If there is one first switch unit Q1, there is also one second switch unit Q2, and the third end of the first switch unit Q1 can be used as the output end 13. When the first end and the third end of the first switch unit Q1 are electrically connected, the first end and the third end of the second switch unit Q2 are electrically disconnected, and the lighting unit L1 corresponding to the first switch unit Q1 can be controlled to emit light; when the first end and the third end of the first switch unit Q1 are electrically disconnected, the first end and the third end of the second switch unit Q2 are electrically connected, and the lighting unit L1 corresponding to the first switch unit Q1 can be controlled to stop emitting light. The first switch unit Q1 can be a switching element, such as a MOS tube (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET, Metal-Oxide Semiconductor Field Effect Transistor), a triode, an IGBT (Insulate-Gate Bipolar Transistor, Insulated Gate Bipolar Transistor), etc. The polarity of the switching element is not limited, such as a MOS tube can be an N-type MOS tube or a P-type MOS tube. In the embodiment of the present application, the first switch unit Q1 is a first MOS tube, the first end of the first switch unit Q1 is the first end of the first MOS tube, the second end of the first switch unit Q1 is the control end of the first MOS tube, and the third end of the first switch unit Q1 is the second end of the first MOS tube.

[0055] The second switch unit Q2 may also be a switch element, such as a MOS tube, a triode, an IGBT, etc. The polarity of the switch element is not limited, such as the MOS tube may be an N-type MOS tube or a P-type MOS tube. In the embodiment of the present application, the second switch unit Q2 is a second MOS tube, the first end of the second switch unit Q2 is the first end of the second MOS tube, the second end of the second switch unit Q2 is the control end of the second MOS tube, and the third end of the second switch unit Q2 is the second end of the second MOS tube.

[0056] Optionally, when there are multiple first switch units Q1, such as two or more, the number of the second switch units Q2 is consistent with the number of the first switch units Q1, and the current control subcircuit 121 further includes a current limiting subcircuit 1211 that is consistent with the number of the first switch units Q1, and the current limiting subcircuit 1211 corresponds to the first switch units Q1 one by one, and the first end of each current limiting subcircuit 1211 is electrically connected to the third end of the first switch unit Q1 corresponding to the current limiting subcircuit 1211, and the second end of each current limiting subcircuit 1211 is the output end 13, and the current limiting subcircuit 1211 is used to limit the current flowing through the current limiting subcircuit 1211, that is, the current limiting subcircuit 1211 allows a preset current to pass through, and the current limiting subcircuit 1211 is like a wire and does not share the voltage in the entire LED lighting circuit 10. The preset current allowed to pass through one current limiting subcircuit 1211 may be different from that allowed to pass through other current limiting subcircuits 1211. For example, the first switch unit Q1 includes four, the second switch unit Q2 also includes four, and the current limiting sub-circuit 1211 also includes four. In the LED lighting circuit 10, the normal working voltage of the lighting unit L1 is 1A, and the currents allowed to pass through the four current limiting sub-circuits 1211 are 0.1A, 0.2A, 0.3A and 0.4A respectively. If the first switch unit Q1 corresponding to the current limiting sub-circuit 1211 of 0.4A is electrically turned on, and the first switch unit Q1 corresponding to the current limiting sub-circuit 1211 of 0.1A, 0.2A and 0.3A is electrically turned off, then the current passing through the lighting unit L1 is 0.4A, and the current passing through the first voltage divider unit R1 corresponding to the lighting unit L1 is 0.1+0.2+0.3=0.6A, while the current passing through the LED lighting circuit 10 is still 1A. By adjusting the electrical connection and disconnection between the first end and the third end of the first switch unit Q1, the brightness of the lighting unit L1 can be adjusted.

[0057] Optionally, each current limiting subcircuit 1211 may include at least one current limiting unit Q3, a first end of the current limiting unit Q3 of each current limiting subcircuit 1211 is electrically connected to a third end of the first switch unit Q1 corresponding to the current limiting subcircuit 1211, a second end of the current limiting unit Q3 of each current limiting subcircuit 1211 is an output end 13, a third end of the current limiting unit Q3 of each current limiting subcircuit 1211 is used to be electrically connected to an external third control circuit, and the current limiting unit Q3 is used to control the electrical conduction between the first end and the second end of the current limiting unit Q3 according to a third control signal received from the third control circuit, and when the first end and the second end of the current limiting unit Q3 are electrically conductive, the current allowed to pass between the first end and the second end of the current limiting unit Q3 is a preset value. If the current of the lighting unit L1 during normal operation is I, the number of the first switch units Q1 is n, and the preset value is m, then m≤I / n. When the preset value m is less than I / n, some of the current limiting sub-circuits 1211 may include multiple current limiting units Q3, but the sum of the currents allowed to pass through the current limiting units Q3 included in one driving unit 12 is the current of the corresponding lighting unit L1 when it is normal. If the first switch unit Q1 includes four, then the current limiting sub-circuit 1211 also includes four, the first current limiting sub-circuit 1211 includes one current limiting unit Q3, the second current limiting sub-circuit 1211 includes two current limiting units Q3, the third current limiting sub-circuit 1211 includes four current limiting units Q3, and the fourth current limiting sub-circuit 1211 includes eight current limiting units Q3, that is, one driving unit 12 includes 15 current limiting units Q3, and the current allowed to pass through each current limiting unit Q3 is I / 15.

[0058] The current limiting unit Q3 is a current limiting switch element, the first end of the current limiting unit Q3 is the first end of the current limiting switch element; the second end of the current limiting unit Q3 is the second end of the current limiting switch element, and the third end of the current limiting unit Q3 is the control end of the current limiting switch element. Specifically, the current limiting switch element can be a current limiting MOS tube, a current limiting transistor or a current limiting insulated gate bipolar transistor, etc.

[0059] See also Figure 4 Optionally, the LED lighting circuit 10 further includes a clamp circuit 14, a first end of the clamp circuit 14 is electrically connected to a first end of the lighting unit L1, that is, electrically connected to the power input terminal 11, and a second end of the clamp circuit 14 is electrically connected to the output terminal 13. The clamp circuit 14 is used to fix a certain part of the pulse signal at a specified voltage value and keep the shape of the original waveform unchanged, so that when the voltage input to the power input terminal 11 fluctuates, the clamp circuit 14 can keep the input voltage stable and will not damage the LED lighting circuit 10.

[0060] The clamping circuit 14 includes a second voltage divider unit R2 and a diode D1, wherein a first end of the second voltage divider unit R2 is electrically connected to a first end of the lighting unit L1; a cathode of the diode D1 is electrically connected to a second end of the second voltage divider unit R2, and an anode of the diode D1 is electrically connected to the output end 13.

[0061] The second voltage dividing unit R2 may be one or more components, such as a resistor; or a plurality of components connected in series or in parallel.

[0062] See also Figure 5 The present application also provides a lighting circuit 20, which includes at least two LED lighting circuits 10 connected in series. The power input end of the first LED lighting circuit 10 is connected to an external power source, the power input end of the subsequent LED lighting circuit 10 is used to be electrically connected to the output end of the previous LED lighting circuit 10, and the output end of the last LED lighting circuit 10 is grounded. A suitable number of LED lighting circuits 10 are connected in series, so that the voltage shared by each LED lighting circuit 10 can be the rated voltage of the LED lighting circuit 10, so that the LED lighting circuit 10 can work normally, and there is no need to adjust the voltage of the input power supply to match the voltage of the LED lighting circuit 10.

[0063] Optionally, if more than three LED lighting circuits 10 are connected in series, the power input terminal of the first LED lighting circuit 10 is electrically connected to an external power supply; the output terminal of the last LED lighting circuit 10 is grounded; and among any two adjacent LED lighting circuits 10, the output terminal of the previous LED lighting circuit 10 is electrically connected to the power input terminal of the next LED lighting circuit 10.

[0064] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0065] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. An LED lighting circuit, characterized in that: include: A power input terminal and at least one lighting unit, wherein a first terminal of each lighting unit is electrically connected to the power input terminal, and the power input terminal is used to be electrically connected to an output terminal or a power supply of a previous LED lighting circuit; A driving circuit, comprising at least one driving unit corresponding to at least one of the lighting units, each of the driving units comprising a first voltage dividing unit and a current control subcircuit; The first end of the first voltage dividing unit is electrically connected to the power input end, and the resistance value of the first voltage dividing unit is the same as the resistance value of the corresponding lighting unit; a current control subcircuit, wherein the first end and the second end are electrically connected to the second end of the corresponding lighting unit and the second end of the corresponding first voltage divider unit, respectively, and are used to control a first current flowing through the corresponding lighting unit and a second current flowing through the corresponding first voltage divider unit, so that the sum of the first current and the second current remains unchanged; The third terminal of the current control subcircuit serves as the output terminal of the LED lighting circuit, and is used to be electrically connected to the power input terminal of the next LED lighting circuit or to be grounded.

2. The LED lighting circuit according to claim 1, characterized in that: The current control subcircuit comprises: At least one first switch unit; one end of each of the first switch units is electrically connected to the second end of the corresponding lighting unit, and is used to control the on and off of the first switch unit according to an external first control signal; At least one second switch unit, each of the second switch units has one end electrically connected to the second end of the corresponding first voltage divider unit, and the other end electrically connected to the other end of the corresponding first switch unit, and is used to control the electrical on-off state of the second switch unit according to an external second control signal, and the electrical on-off state of each second switch unit is opposite to the electrical on-off state of the corresponding first switch unit.

3. The LED lighting circuit according to claim 2, characterized in that: Each of the first switch units has a first end electrically connected to the second end of the corresponding lighting unit, and a second end electrically connected to an external first control circuit, and is used to control the electrical on-off state between the first end and the third end of the first switch unit according to a first control signal of the first control circuit, and the electrical on-off state of any one of the first switch units is the same as or different from the electrical on-off state of other first switch units; Each of the second switch units has a first end electrically connected to the second end of the corresponding first voltage divider unit, a second end for electrically connecting to an external second control section, and a third end electrically connected to the third end of the corresponding first switch unit, for controlling the electrical on / off state between the first end and the third end of the second switch unit according to the second control signal of the second control circuit.

4. The LED lighting circuit according to claim 3, characterized in that: The current control subcircuit also includes: The number of current limiting sub-circuits is consistent with that of the first switch units, the current limiting sub-circuits correspond one-to-one to the first switch units, the first end of each current limiting sub-circuit is electrically connected to the third end of the first switch unit corresponding to the current limiting sub-circuit, and the second end of each current limiting sub-circuit is an output end.

5. The LED lighting circuit according to claim 4, characterized in that: Each of the current limiting sub-circuits comprises: At least one current limiting unit, the first end of the current limiting unit of each current limiting sub-circuit is electrically connected to the third end of the first switch unit corresponding to the current limiting sub-circuit, the second end of the current limiting unit of each current limiting sub-circuit is an output end, and the third end of the current limiting unit of each current limiting sub-circuit is used to be electrically connected to an external third control circuit, and the current limiting unit is used to control the electrical conduction between the first end and the second end of the current limiting unit according to a third control signal received from the third control circuit, and when the first end and the second end of the current limiting unit are electrically conductive, the current allowed to pass between the first end and the second end of the current limiting unit is a preset value.

6. The LED lighting circuit according to claim 5, characterized in that: The current limiting unit is a current limiting switch element, the first end of the current limiting unit is the first end of the current limiting switch unit; the second end of the current limiting unit is the second end of the current limiting switch unit, and the third end of the current limiting unit is the control end of the current limiting switch element.

7. The LED lighting circuit according to claim 1, characterized in that: The LED lighting circuit also includes: A clamping circuit, wherein a first end of the clamping circuit is electrically connected to a first end of the lighting unit, and a second end of the clamping circuit is electrically connected to the output end.

8. The LED lighting circuit according to claim 7, characterized in that: The clamping circuit comprises: a second voltage dividing unit, wherein a first end of the second voltage dividing unit is electrically connected to a first end of the lighting unit; A diode, wherein a cathode of the diode is electrically connected to the second end of the second voltage dividing unit, and an anode of the diode is electrically connected to the output end.

9. The LED lighting circuit according to claim 2, characterized in that: The first switch unit is a first MOS tube, the first end of the first switch unit is the first end of the first MOS tube, the second end of the first switch unit is the control end of the first MOS tube, and the third end of the first switch unit is the second end of the first MOS tube; The second switch unit is a second MOS tube, the first end of the second switch unit is the first end of the second MOS tube, the second end of the second switch unit is the control end of the second MOS tube, and the third end of the second switch unit is the second end of the second MOS tube.

10. A lighting circuit, characterized in that: include: At least two LED lighting circuits according to any one of claims 1 to 9 are connected in series.

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