Low power consumption dimming circuit and intelligent lamps

Abstract

The present invention provides a low-power dimming circuit and an intelligent lamp. The low-power dimming circuit includes a dimmer and a dimmer identification circuit. The dimmer is connected to more than two dimmer identification circuits. Each dimmer identification circuit is connected to a dimming power supply. Multiple dimmer identification circuits are connected in parallel. Each dimmer identification circuit has a voltage follower. The voltage follower receives the voltage of the dimmer and outputs a signal to a controller. The dimmer identification circuit has a dimmer port. The dimmer is connected to the dimmer port, and a DC power supply supplies power to the dimmer port. The present invention also provides an intelligent lamp with the above-mentioned dimming circuit. The present invention can reduce the power consumption of the dimming power supply at the dimmer port. One dimmer can be connected to more dimming power supplies, thereby reducing the production cost of the intelligent lamp.

Description

Technical Field

[0001] The present invention relates to the field of control of intelligent lamps, and in particular to a low-power dimming circuit and an intelligent lamp provided with the low-power dimming circuit. Background Art

[0002] In recent years, the application of smart lamps has become more and more widespread. At present, many smart lamps use LED chips as light-emitting devices. Most of the current smart lamps have a dimming function, that is, the brightness of the lamp can be adjusted. Usually, the current smart lamps are equipped with a dimmer, and the user adjusts the brightness of the smart lamp through the dimmer. For example, the voltage signal output by the dimmer can vary between 0 and 10V or 1 to 10V. The greater the output voltage, the greater the brightness of the smart lamp, and the smaller the output voltage, the smaller the brightness of the smart lamp. After receiving the dimming signal, the controller of the smart lamp adjusts the brightness of the LED according to the received dimming signal.

[0003] With the development of smart lamp technology, users have higher and higher requirements for the energy efficiency of smart lamps. For example, the current of a single dimming power supply corresponding to a common dimmer on the market is 0.113mA to 0.18mA. Usually, multiple groups of LED chips are set in smart lamps, for example, each group of LED chips has a different color temperature or a different color. Of course, multiple groups of LED chips can also have the same color temperature and the same color.

[0004] Since the luminous brightness of multiple groups of LED chips can be adjusted synchronously, multiple groups of LED chips can be adjusted through one dimmer. Usually, a group of LED chips is powered by one dimming power supply. Therefore, one dimmer can be connected to multiple dimming power supplies. The luminous brightness of multiple groups of LED chips can be adjusted simultaneously through one dimmer.

[0005] However, since the power of each dimmer is limited, the number of dimming power supplies that can be connected to a dimmer is often limited by the power of the dimmer. If you want a dimmer to be able to connect multiple dimming power supplies, you need to reduce the power of each dimming power supply at the dimmer port, especially the current of each dimming power supply at the dimmer port. However, existing smart lamps often do not effectively limit the current at the dimmer port, resulting in a small number of dimming power supplies connected to a dimmer. Summary of the invention

[0006] A first object of the present invention is to provide a low-power dimming circuit that enables a dimmer to connect more dimming power supplies.

[0007] A second object of the present invention is to provide an intelligent lamp having the above-mentioned low-power consumption dimming circuit.

[0008] To achieve the first purpose of the present invention, the low-power dimming circuit provided by the present invention includes a dimmer and a dimmer identification circuit, the dimmer is connected to more than two dimmer identification circuits, each dimmer identification circuit is connected to a dimming power supply, and multiple dimmer identification circuits are connected in parallel; each dimmer identification circuit has a voltage follower, the voltage follower receives the voltage of the dimmer, and the voltage follower outputs a signal to a controller; the dimmer identification circuit has a dimmer port, the dimmer is connected to the dimmer port, and a DC power supply supplies power to the dimmer port.

[0009] It can be seen from the above scheme that the maximum bias current of the voltage follower is often only about 30 nanoamperes. Connecting the dimmer port to an input port of the voltage follower makes the current of a dimming power supply at the dimmer port only about 30 nanoamperes. The other power supply of the dimming power supply can be provided by a DC power supply. In this way, the current of the dimmer at the dimmer port can be minimized, thereby reducing the power at the dimmer port.

[0010] It can be seen that the power consumption of each dimming power supply for the dimmer is very low. Compared with the traditional dimming circuit, the present invention can enable the dimmer to connect more dimmer power supplies, thereby reducing the production cost of the intelligent lamp.

[0011] In a preferred solution, the maximum bias current of the voltage follower is between 25 nanoamperes and 35 nanoamperes. More preferably, the maximum bias current of the voltage follower is 30 nanoamperes.

[0012] It can be seen that the maximum bias current of the voltage follower is very small. For each dimming power supply, this connection method can reduce the power formed by the dimming power supply at the dimmer, providing conditions for the dimmer to connect more dimming power supplies.

[0013] A further solution is that the dimmer identification circuit is further provided with a first switch device, the first switch device receives a control signal output by the controller, and the first switch device controls the DC power supply to load a DC voltage to the dimmer port.

[0014] Since one of the two existing dimmers is passive and the other is active, the DC power supply is controlled by the first switch to load the DC power supply to the dimmer port, and the voltage output by the voltage follower is detected to be constant, thereby determining whether the dimmer to be detected is an active dimmer or a passive dimmer.

[0015] A further solution is that the dimmer identification circuit further includes a second switch device, a control end of the second switch device is connected to a current signal end of the first switch device, and one end of the second switch device is connected to a DC power supply.

[0016] It can be seen that the first switch device controls the on and off of the second switch device, and then uses the second switch device to control the DC power supply to supply power to the dimmer port, which can achieve isolation between the controller signal and the power supply signal and avoid the high-voltage signal of the DC power supply affecting the controller pins.

[0017] In a further solution, the dimmer identification circuit further includes a diode, wherein the positive terminal of the diode is connected to the second switch device, and the negative terminal of the diode is connected to the dimmer port.

[0018] In this way, the diode can ensure that the current of the DC power supply flows unidirectionally to the dimmer port, thereby preventing the current from flowing from the dimmer port in the reverse direction to the second switch device and affecting the operation of the second switch device.

[0019] A further solution is to provide a filter capacitor between the dimmer port and the ground terminal, so that the current of the dimmer port is more stable, and the accuracy of dimmer type detection is improved.

[0020] To achieve the above second objective, the intelligent lamp provided by the present invention includes an LED light source and is also provided with the above low-power dimming circuit, and the controller outputs a dimming control signal to the LED light source.

[0021] A preferred solution is that a low power consumption dimming circuit outputs a dimming control signal to at least one LED light source.

[0022] It can be seen that each low-power dimming circuit can be connected to one or more LED light sources, so that the smart lamp can be equipped with more LED light sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural block diagram of an embodiment of a low power consumption dimming circuit of the present invention.

[0024] Figure 2 It is an electrical schematic diagram of a controller of an embodiment of a low power consumption dimming circuit of the present invention.

[0025] Figure 3 It is an electrical schematic diagram of an identification interface circuit of an embodiment of a low-power dimming circuit of the present invention.

[0026] Figure 4 It is a flow chart of the control method of the intelligent lamp embodiment of the present invention.

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0028] The smart lamp of the present invention is an LED lamp with an LED chip, and a low-power dimming circuit and a plurality of LED light sources are provided in the smart lamp, and each LED light source can be a group of LED chips. A dimmer is provided in the smart lamp of the present invention, and the dimmer is used to adjust the luminous brightness of the smart lamp. In view of the fact that the dimming signal output by the common dimmer or the main controller of the smart lamp is mainly divided into 0 to 10V or 1 to 10V, the smart lamp is also provided with a dimmer identification circuit, and the dimmer identification circuit is used to identify the type of the dimmer. In addition, a dimmer can be connected to multiple dimming power supplies, for example, the dimming power supply includes a dimming identification circuit, and therefore, a dimmer is connected to one or more dimmer identification circuits. The low-power dimming circuit of the present invention includes a dimmer and a dimmer identification circuit.

[0029] See also Figure 1 The dimmer identification circuit 10 has a controller 11 and an identification interface circuit 12. The dimmer identification circuit 10 can be connected to a dimmer 20. Preferably, one dimmer 20 can be connected to multiple dimmer identification circuits 10. The dimmer identification circuit 10 receives a voltage signal from the dimmer 20 and determines the type of the dimmer according to the voltage signal of the dimmer 20.

[0030] At present, the dimming signals output by the main controller of the common dimmer or intelligent lamp are mainly divided into two types: 0 to 10V or 1 to 10V. Among them, the dimmer with an output voltage range of 0V to 10V is usually an active dimmer, that is, the dimmer has its own power supply and does not need the dimmer power supply to provide the power required for its operation; and the dimmer with an output voltage range of 1V to 10V is usually a passive dimmer, that is, the dimmer has no power supply itself and needs the dimmer power supply to provide the power required for its operation. Usually, the controller or dimmer power supply needs to provide a pull-up voltage of about 10V to meet its working requirements. This embodiment uses this feature to identify the two types of dimmers.

[0031] See also Figure 2 and Figure 3 , two pins of the controller U2 are connected to the identification interface circuit 12, for example, pin PD3 is used to output a control signal to the identification interface circuit 12, and pin PD2 receives an identification signal output by the interface circuit 12. The identification interface circuit 12 is provided with a voltage follower U1A, and the output end of the voltage follower U1A is connected to the pin PD2 of the controller U2 through a resistor R3, so the controller U2 can receive the voltage signal output by the voltage follower U1A, that is, the identification signal.

[0032] The input end of the voltage follower U1A is connected to the dimmer port TD1 through the resistor R1, and the dimmer port TD1 is connected to the dimmer 20. The signal output by the dimmer 20 is received by the dimmer port TD1 and input to the input end of the voltage follower U1A. In this way, the voltage follower U1A receives the voltage signal input by the dimmer 20, and its output voltage changes with the input voltage. The controller U2 can determine the change in the voltage output by the dimmer 20 based on the received identification signal.

[0033] A Zener diode D1 is connected between the dimmer port TD1 and the ground terminal. When the dimmer 20 outputs a DC voltage to the dimmer port TD1, the Zener diode D1 can keep the voltage of the dimmer port TD1 stable, so that the voltage output by the voltage follower U1A also remains stable, thereby stabilizing the voltage of the identification signal received by the controller U2, thereby improving the accuracy of the controller U2 in identifying the type of the dimmer 20.

[0034] In addition, the input end of the voltage follower U1A is also connected to a filter capacitor C1. The voltage output from the dimmer port TD1 is input to the voltage follower U1A after passing through the filter capacitor C1, making the voltage signal input to the voltage follower U1A more stable, thereby improving the accuracy of the controller U2 in identifying the type of the dimmer 20.

[0035] The output end of the voltage follower U1A is provided with voltage divider resistors R3 and R4, and the voltage signal output by the voltage follower U1A is divided by the voltage divider resistors R3 and R4 and then output to the controller U2. Furthermore, the voltage divider resistor R4 is connected in parallel with the filter capacitor C2 to improve the stability of the identification signal input to the controller U2.

[0036] The identification interface circuit 12 is also provided with a first switch device Q1 and a second switch device Q2, wherein the first switch device Q1 is a field effect transistor and the second switch device Q2 is a triode. The control end, i.e., the gate, of the first switch device Q1 is connected to the pin PD3 of the controller U2 and receives the control signal output by the controller U2, so the first switch device Q1 is controlled on and off by the controller U2. The first switch device Q1 is a high-level conductive device, and its drain is grounded.

[0037] The second switch device Q2 is a low-level conductive device, and its base is connected to the source of the first switch device Q1 through a resistor R2. In addition, the base is also connected to the DC power supply through a resistor R6. The emitter of the second switch device Q2 is connected to the DC power supply. In this embodiment, the voltage of the DC power supply is 12V. The collector of the second switch device Q2 is connected to the positive terminal of the diode D2 through a resistor R5, and the negative terminal of the diode D2 is connected to the dimmer port TD1.

[0038] When the dimmer 20 is connected to the dimmer port TD1, the PD3 pin of the controller U2 outputs a low-level signal. At this time, the first switch device Q1 is in the off state, a high-level signal is formed on the base of the second switch device Q2, and the second switch device Q2 is also in the off state. At this time, the DC power supply cannot supply power to the dimmer port TD1 through the second switch device Q2.

[0039] If the dimming range of the dimmer 20 is 0 to 10V, that is, the dimmer 20 is an active dimmer, then when the DC power supply does not supply power to the dimmer port TD1, the dimmer 20 can still be powered by its own power supply. When the voltage signal output by the dimmer 20 remains unchanged, the voltage value received by the dimmer port TD1 remains constant, so that the voltage value of the identification signal received by the controller U2 through the voltage follower U1A remains unchanged.

[0040] If the dimming range of the dimmer 20 is 1V to 10V, that is, the dimmer 20 is a passive dimmer, then when the DC power supply does not supply power to the dimmer port TD1, the dimmer 20 will not be powered. When the voltage signal output by the dimmer 20 remains unchanged, the voltage value received by the dimmer port TD1 will continue to decrease, so that the voltage of the identification signal received by the controller U2 through the voltage follower U1A also decreases. It can be seen that the type of the dimmer 20 can be determined by the identification signal output by the identification interface circuit 12.

[0041] In addition, in this embodiment, the bias current of the voltage follower U1A is at most 30 nanoamperes, so for each dimmer identification circuit, the input current at the dimmer port TD1 is only 30 nanoamperes at most relative to the voltage follower U1A, and the remaining power required for the dimmer identification circuit to work is provided by the dimming power supply itself, which can reduce the input current at the dimmer port TD1, thereby reducing the power of the dimmer 20 at the dimmer port TD1. It can be understood that the voltage formed by each dimmer power supply at the interface of the dimmer 20 will be greatly reduced compared to the traditional dimming circuit. In this way, when the total power of the dimmer 20 is limited, one dimmer 20 can be connected to more dimming power supplies.

[0042] Preferably, multiple dimming power supplies are connected in parallel, and a low-power dimming circuit outputs a dimming control signal to one or more LED light sources. For a dimming power supply, the input current can be between 0.027uA and 12.2uA. Part of the input current is loaded to the dimmer port TD1, and the other part provides the electrical energy required for the LED chip to emit light.

[0043] Combine the following Figure 4A method for a dimmer identification circuit to identify a dimmer is introduced, and a method for an intelligent lamp to automatically set the intelligent lamp by applying the identification method. First, step S1 is executed, the dimmer 20 is connected to the dimmer identification circuit 10, and the dimmer port TD1 of the identification interface circuit 12 receives a voltage signal from the dimmer 20. At this time, the controller U2 outputs a low-level signal to the first switch device Q1. At this time, the first switch device Q1 is turned off, and the second switch device Q2 is also turned off. Therefore, the 12V DC power supply cannot supply power to the dimmer port TD1 through the second switch device Q2.

[0044] Next, step S2 is executed, the dimmer port TD1 reveals the voltage from the dimmer 20, and the voltage of the dimmer 20 passes through the voltage follower U1A to form an identification signal and output to the controller U2. The controller U2 executes step S3 to determine whether the voltage of the dimmer 20 remains constant. If the dimming range of the dimmer 20 is 0 to 10V, that is, the dimmer 20 is an active dimmer, then when the DC power supply does not supply power to the dimmer port TD1, the dimmer 20 can still be powered by its own power supply. When the voltage signal output by the dimmer 20 remains unchanged, the voltage value received by the dimmer port TD1 remains constant, so that the voltage value of the identification signal received by the controller U2 through the voltage follower U1A remains unchanged.

[0045] Therefore, if the judgment result of step S3 is yes, it means that the dimmer 20 is an active dimmer, and its dimming range is 0 to 10V, and the dimmer is a first-class dimmer; if the judgment result of step S3 is no, it means that the dimmer 20 is a passive dimmer, and its dimming range is 1V to 10V, and the dimmer is a second-class dimmer.

[0046] If only the above conditions are used to confirm the type of the dimmer, there may be a misjudgment. In order to improve the accuracy of the detection, this embodiment also introduces a second judgment condition, and the minimum voltage value read during the dimming process is used as the second judgment condition. Specifically, if the dimming range of the dimmer 20 is 0 to 10V, the minimum voltage value during the dimming process can obviously be adjusted to below 1V. If the dimming range of the dimmer 20 is 1V to 10V, the minimum voltage value during the dimming process cannot be adjusted to below 1V.

[0047] Therefore, if the judgment result of step S3 is yes, step S4 is executed to confirm that the dimmer 20 is an active dimmer, and then determine whether the minimum voltage value of the dimmer 20 during the dimming process is lower than the minimum voltage value of the second type of dimmer, for example, whether it can reach below 1V. Further, it can be determined whether the minimum voltage value during the dimming process can reach the minimum voltage value of the first type of dimmer, that is, 0V. If the above conditions are met, step S5 is executed to confirm that the currently connected dimmer is a first type of dimmer.

[0048] If the judgment result of step S3 is no, it is confirmed that the currently connected dimmer is a passive dimmer, and step S7 is executed to determine whether the minimum voltage value of the dimmer 20 during the dimming process cannot reach the minimum voltage value of the first type of dimmer. If so, step S8 is executed to confirm that the currently connected dimmer is a second type of dimmer.

[0049] In this way, by combining the two judgment conditions, the type of the currently connected dimmer can be accurately confirmed. Finally, execute step S6 to adjust the dimming voltage range of the smart lamp according to the dimmer type confirmed in step S5 or step S8. Specifically, adjust the dimming start voltage range of the smart lamp and / or the dimming turn-off voltage range of the smart lamp according to the confirmed dimmer type. For example, after confirming that the dimmer to be identified is a first-class dimmer, set the minimum value of the dimming start voltage range of the smart lamp and / or the dimming turn-off voltage range of the smart lamp to the minimum voltage value of the first-class dimmer during the dimming process. If it is confirmed that the dimmer to be identified is a first-class dimmer, set the minimum value of the dimming start voltage range of the smart lamp and / or the dimming turn-off voltage range of the smart lamp to the minimum voltage value of the first-class dimmer during the dimming process, that is, set the minimum value of the dimming start voltage range and / or the dimming turn-off voltage range of the smart lamp to 0V. If it is confirmed that the dimmer to be identified is a second-class dimmer, the minimum value of the dimming start-up voltage range and / or the dimming turn-off voltage range of the smart lamp is set to the minimum voltage value of the second-class dimmer during the dimming process, that is, the minimum value of the dimming start-up voltage range and / or the dimming turn-off voltage range of the smart lamp is set to 1V.

[0050] It can be seen that through the method of the present invention, the type of dimmer can be simply identified, and the minimum values ​​of the dimming start-up voltage and the dimming off voltage can be automatically set to match the type of dimmer, so that the dimming voltage output by the controller matches the type of dimmer. The controller can be compatible with two types of dimmers, thereby improving the compatibility of the controller and reducing the production cost of smart lamps.

[0051] In addition, the present invention can realize that one dimmer is connected to multiple dimming power supplies, thereby reducing the power consumption of the dimming power supplies. Since multiple dimming power supplies can share one dimmer to achieve dimming, the production cost of the intelligent lamp can be reduced.

[0052] Finally, it should be emphasized that the present invention is not limited to the above-mentioned embodiments. For example, changes in the minimum voltage during the dimming process of the two dimmers, or changes in the types of two switching devices, etc., should also be included in the scope of protection of the claims of the present invention.

Claims

1. Low power consumption dimming circuit, characterized in that: include: A dimmer and a dimmer identification circuit, wherein the dimmer is connected to two or more dimmer identification circuits, each of the dimmer identification circuits is connected to a dimming power supply, and the multiple dimmer identification circuits are connected in parallel; Each of the dimmer identification circuits has a voltage follower, the voltage follower receives the voltage of the dimmer, and the voltage follower outputs a signal to the controller; The dimmer identification circuit has a dimmer port, the dimmer is connected to the dimmer port, and a DC power source supplies power to the dimmer port; The input current of each dimmer identification circuit at the dimmer port does not exceed the maximum bias current relative to the voltage follower, and the remaining power required for the operation of the dimmer identification circuit is provided by the dimming power supply itself.

2. The low power consumption dimming circuit according to claim 1, characterized in that: The maximum bias current of the voltage follower is between 25 nanoamperes and 35 nanoamperes.

3. The low power consumption dimming circuit according to claim 2, characterized in that: The maximum bias current of the voltage follower is 30 nanoamperes.

4. The low power consumption dimming circuit according to any one of claims 1 to 3, characterized in that: The dimmer identification circuit is further provided with a first switch device, the first switch device receives a control signal output by the controller, and the first switch device controls the DC power supply to load a DC voltage to the dimmer port.

5. The low power consumption dimming circuit according to claim 4, characterized in that: The dimmer identification circuit further includes a second switch device, a control end of the second switch device is connected to a current signal end of the first switch device, and one end of the second switch device is connected to the DC power supply.

6. The low power consumption dimming circuit according to claim 5, characterized in that: The dimmer identification circuit further includes a diode, an anode terminal of the diode is connected to the second switch device, and a cathode terminal of the diode is connected to the dimmer port.

7. The low power consumption dimming circuit according to claim 4, characterized in that: A filter capacitor is arranged between the dimmer port and the ground terminal.

8. An intelligent lamp, including an LED light source, characterized in that: A low-power dimming circuit as described in any one of claims 1 to 6 is also provided, and the controller outputs a dimming control signal to the LED light source.

9. The intelligent lamp according to claim 8, characterized in that: One of the low power consumption dimming circuits outputs a dimming control signal to at least one LED light source.

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