LED lamp bead driving system

Abstract

An LED lamp bead driving system comprises a switching power supply isolation driving module, an LED driving voltage adjusting module, a controller and one or more lamp bead driving chips. The switching power supply isolation driving module is configured to convert an AC voltage into a DC voltage. The LED driving voltage adjusting module is configured to provide an LED driving voltage based on the DC voltage from the switching power supply isolation driving module. The controller is configured to receive link-level driving voltage information from each lamp bead driving chip and send a boost or buck feedback control signal to the LED driving voltage adjusting module based on the received link-level driving voltage information. And the LED driving voltage regulation module carries out boost or buck regulation on the LED driving voltage based on the boost or buck feedback control signal.

Description

Technical Field

[0001] This invention relates generally to the field of circuits, and more particularly to an LED bead driving system. Background Technology

[0002] With the development of light-emitting diode (LED) lighting technology, people's requirements for LED lighting effects have increased. Besides requiring conventional white light illumination, they also demand the display of different color spectra and dynamic effects such as "blue sky and white clouds." In response to these needs, lighting products such as color-changing lights have been launched on the market. Typically, color-changing lights are composed of multiple sets of red, green, blue, and white LED beads. The brightness of the LED beads in different areas can be independently adjusted and controlled according to user needs. The required illuminance is achieved through white LED beads, and different color spectra are achieved through the brightness ratio of red, green, and blue LED beads. Summary of the Invention

[0003] An LED chip driving system according to an embodiment of the present invention includes: a switching power supply isolation driving module, an LED driving voltage regulation module, a controller, and one or more LED chip driving chips, wherein: the switching power supply isolation driving module is configured to convert AC voltage to DC voltage; the LED driving voltage regulation module is configured to provide LED driving voltage based on the DC voltage from the switching power supply isolation driving module; the controller is configured to receive link-level driving voltage information from each of the one or more LED chip driving chips via a single-wire bus, and send a boost feedback control signal or a buck feedback control signal to the LED driving voltage regulation module based on the received link-level driving voltage information. This allows the LED driver voltage regulation module to boost the LED driver voltage based on a boost feedback control signal or buck the LED driver voltage based on a buck feedback control signal. Each LED driver chip in one or more LED driver chips includes one or more LED channels. The link-level drive voltage information of each LED driver chip in one or more LED driver chips includes information indicating the number of LED driver chips in that LED driver chip that require the LED driver voltage to be increased, decreased, or unchanged, or information indicating the number of LED channels in that LED driver chip that require the LED driver voltage to be increased, decreased, or unchanged. Attached Figure Description

[0004] The invention can be better understood from the following description of specific embodiments of the invention in conjunction with the accompanying drawings, wherein:

[0005] Figure 1 It shows Figure 1 A connection diagram of an LED bead driving system according to an embodiment of the present invention is shown.

[0006] Figure 2 It shows Figure 1 The diagram shows the structure of the circuit related to any one of the LED channels in the LED driver chip.

[0007] Figure 3 It shows Figure 1 The diagram shows the structure of the circuitry used to process drive voltage information in the LED driver chip.

[0008] Figure 4 It shows the use of Figure 1 The diagram shows a schematic flowchart of the control method for the LED bead driving system. Detailed Implementation

[0009] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a comprehensive understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific configuration and algorithm presented below, but covers any modifications, substitutions, and improvements to elements, components, and algorithms without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description in order to avoid unnecessarily obscuring the invention. Furthermore, it should be noted that the term "A connected to B" as used herein can mean "A and B are directly connected" or "A and B are indirectly connected via one or more other elements."

[0010] Currently, the LED driving voltage for various LED beads used in RGB lighting is provided by switching power supply modules with fixed voltage outputs such as 12V / 24V. Since RGB lighting contains multiple sets of red, green, blue, and white LED beads, and these LED beads have different brightness and on-time, if the forward voltage (VF) of the LED beads is too high, the brightness of the LED beads will be lower than expected; if the VF of the LED beads is too low, it will cause power loss and affect the overall system efficiency. Therefore, a suitable solution is needed, using a general-purpose constant voltage driver power supply, to automatically adjust the LED driving voltage to the optimal voltage for the LED beads.

[0011] In view of the above, an LED driving system according to an embodiment of the present invention is proposed, which can automatically adjust the LED driving voltage for LED chips to the optimal voltage.

[0012] Figure 1 A connection diagram of an LED bead driving system according to an embodiment of the present invention is shown. Figure 1 As shown, the LED bead driving system 100 includes a switching power supply isolated driving module 102, an LED driving voltage regulation module 104, a controller 106, and one or more LED bead driving chips. The switching power supply isolated driving module 102 is configured to convert AC voltage to DC voltage. The LED driving voltage regulation module 104 is configured to provide LED driving voltage to the LED beads and chip power supply voltage to the LED bead driving chip 108 based on the DC voltage from the switching power supply isolated driving module 102. The controller 106 is configured to send control signals to each LED bead driving chip via a single-wire bus and receive link-level driving voltage information from each LED bead driving chip (e.g., the first or last stage LED bead driving chip in each channel), and send a boost feedback control signal or a buck feedback control signal to the LED driving voltage regulation module 104 based on the received link-level driving voltage information, so that the LED driving voltage regulation module 104 performs boost regulation of the LED driving voltage based on the boost feedback control signal or buck regulation of the LED driving voltage based on the buck feedback control signal. Here, each LED driver chip in each LED driver chip includes one or more LED channels. The link-level drive voltage information of each LED driver chip includes information indicating the number of LED driver chips in that LED driver chip that require the LED drive voltage to be increased, decreased, or unchanged, or information indicating the number of LED channels in that LED driver chip that require the LED drive voltage to be increased, decreased, or unchanged.

[0013] like Figure 1 As shown, in the LED bead driving system 100, each bead driving chip includes one or more bead driving chips 108. Adjacent bead driving chips in each bead driving system are arranged in series with signal output ports and signal input ports connected. The last bead driving chip in each bead driving system can be connected to the controller 106 or not.

[0014] like Figure 1 As shown, in the LED driver system 100, each LED driver chip includes an LED driver circuit for one or more LEDs, and also includes a signal input port and a signal output port. The controller 106 may have one or more control areas, and each control area may include one or more LED driver chips.

[0015] Figure 2 It shows Figure 1 The diagram shows the structural structure of the circuitry related to any one LED channel in the LED driver chip. (See diagram for example.) Figure 2As shown, in each LED driver chip 108, when any LED channel is turned on, the LED driving current flows through the LED connected to that LED channel and generates a voltage drop across the LED. At this time, the LED driving voltage can be determined based on the negative terminal voltage VLEDx of the LED to determine whether the LED driving voltage meets the predetermined requirements. In some cases, the set voltage corresponds to the predetermined requirements. When the voltage judgment unit detects that the negative terminal voltage VLEDx of the LED is lower than the set voltage, it can determine that the LED driving voltage is too low and therefore needs to be increased accordingly, and generate channel-level driving voltage information indicating that the LED driving voltage needs to be increased; when the voltage judgment unit detects that the negative terminal voltage VLEDx of the LED is higher than the set voltage, it can determine that the LED driving voltage is too high and therefore needs to be decreased accordingly, and generate channel-level driving voltage information indicating that the LED driving voltage needs to be decreased; when the voltage judgment unit detects that the negative terminal voltage VLEDx of the LED is equal to the set voltage, it can determine that the LED driving voltage is the optimal voltage and therefore does not need to be changed, and generate channel-level driving voltage information indicating that the LED driving voltage needs to remain unchanged. Since the on-time of each LED channel is different, a certain time period can be set for each LED channel, such as one or more pulse width modulation cycles. During this time period, the voltage judgment unit for that LED channel determines whether the LED driving voltage is too high or too low (i.e., for different LED channels in the LED driver chip, the LED driving voltage can be judged to meet the predetermined requirements at different time periods). When an LED channel is turned off for a long time, or when the brightness of the LED connected to that LED channel is set to a low level, or when the LED channel malfunctions, since the negative terminal voltage of the LED connected to that LED channel cannot be obtained, the voltage judgment unit can determine that the LED driving voltage does not need to be changed. It should be noted that the above-mentioned set voltages can be equal or unequal for different LED channels.

[0016] Figure 3 It shows Figure 1 The diagram shows the structural schematic of the circuitry used to process drive voltage information in the LED driver chip. Figure 3 As shown, in each LED driver chip 108, channel-level driving voltage information from the voltage judgment unit for each LED channel, indicating whether the corresponding LED channel needs a decrease, increase, or no change in LED driving voltage, is summarized to obtain chip-level driving voltage information. The chip-level driving voltage information includes information indicating whether the LED driver chip needs an increase, decrease, or no change in LED driving voltage, or includes one or more of the following: the number of LED channels that need an increase in LED driving voltage, the number of LED channels that need a decrease in LED driving voltage, and the number of LED channels that need no change in LED driving voltage.

[0017] like Figure 1 and Figure 3 As shown, in the LED bead driving system 100, each bead driver chip receives link-level driving voltage information from the previous bead driver chip through a signal input port. By performing logical operations on the link-level driving voltage information and the chip-level driving voltage information of the bead driver chip itself, the chip-level driving voltage information of the bead driver chip is added to the link-level driving voltage information. Then, the link-level driving voltage information is sent to the next-level bead driver chip or controller 106 through a signal output port.

[0018] like Figure 1 As shown, in the LED bead driving system 100, the controller 106, based on the received link-level driving voltage information, can determine whether the LED driving voltage needs to be increased, decreased, or unchanged in each control area it controls, or it can obtain the number of LED driver chips or LED channels in the LED driver chips it controls that require the LED driving voltage to be increased, decreased, or unchanged. Simultaneously, the controller 106 can send a boost feedback control signal or a buck feedback control signal to the LED driving voltage adjustment module 104 based on the number of control areas it controls that require the LED driving voltage to be increased, decreased, or unchanged, the number of LED driver chips in the LED driver chips it controls that require the LED driving voltage to be increased, decreased, or unchanged, or the number of LED channels in the LED driver chips it controls that require the LED driving voltage to be increased, decreased, or unchanged.

[0019] Figure 4 It shows the use of Figure 1 The diagram shows a schematic flowchart of the control method for the LED bead driving system. Figure 4 As shown, for Figure 1 The control method 400 of the LED bead driving system shown includes: S402, where each LED bead driver chip 108 obtains channel-level driving voltage information of each LED channel; S404, where each LED bead driver chip 108 summarizes the channel-level driving voltage information of each LED channel to obtain chip-level driving voltage information; S406, where each LED bead driver chip 108 receives link-level driving voltage information from its preceding LED bead driver chip, adds its own chip-level driving voltage information to the link-level driving voltage information, and sends the link-level driving voltage information to its next-level LED bead driver chip or controller; S408, where the controller 106 receives link-level driving voltage information from the first or last LED bead driver chip in each LED bead driver chip, and sends a boost feedback control signal or a buck feedback control signal to the LED driving voltage adjustment module 104 based on the received link-level driving voltage information.

[0020] For example, when the controller 106 determines that the number of control regions in the control region it controls that require an increase in LED driving voltage is higher than a first region number threshold, it sends a boost feedback control signal to the LED driving voltage adjustment module 104. When it determines that the number of control regions in the control region it controls that require a decrease in LED driving voltage is higher than a second region number threshold, it sends a buck feedback control signal to the LED driving voltage adjustment module 104. And when it determines that the number of control regions in the control region it controls that require no change in LED driving voltage is higher than a third region number threshold, it does not send a boost feedback control signal or a buck feedback control signal to the LED driving voltage adjustment module 104 (i.e., it does not require the LED driving voltage adjustment module 104 to boost or buck adjust the LED driving voltage).

[0021] For example, when the controller 106 determines that the number of LED channels in the LED driver chip it controls that require an increased LED driving voltage is higher than a first channel number threshold, it sends a boost feedback control signal to the LED driver voltage adjustment module 104. When it determines that the number of LED channels in the LED driver chip it controls that require a decreased LED driving voltage is higher than a second channel number threshold, it sends a buck feedback control signal to the LED driver voltage adjustment module 104. And when it determines that the number of LED channels in the LED driver chip it controls that require no change in LED driving voltage is higher than a third channel number threshold, it does not send a boost feedback control signal or a buck feedback control signal to the LED driver voltage adjustment module 104 (i.e., it does not require the LED driver voltage adjustment module 104 to adjust the LED driving voltage by boosting or bucking).

[0022] In some embodiments, the switching power supply isolation driver module 102 includes a general-purpose switching power supply module with a fixed voltage output such as 12V / 24V. The LED driver voltage regulation module 104 includes a DC / DC power supply module employing a conventional DC-DC conversion architecture, such as a buck-boost architecture, a boost architecture, or a buck architecture. The chip supply voltage provided by the LED driver voltage regulation module 104 to the LED driver chip 108 can be 3.3V, 5V, or other voltages different from the LED driving voltage. The controller 106 sends a boost feedback control signal or a buck feedback control signal to the LED driver voltage regulation module 104 via a single-wire communication protocol.

[0023] This invention can be implemented in other specific forms without departing from its spirit and essential characteristics. For example, the algorithm described in a particular embodiment can be modified without departing from the basic spirit of the invention. Therefore, the present embodiments are to be regarded as exemplary rather than limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and all changes falling within the meaning and scope of the claims and their equivalents are thus included within the scope of the invention.

Claims

1. A LED lamp bead driving system, comprising a switching power supply isolation driving module, a LED driving voltage adjusting module, a controller, and one or more lamp bead driving chips, wherein: the switching power supply isolation driving module is configured to convert an alternating voltage into a direct voltage; the LED driving voltage adjusting module is configured to provide a LED driving voltage based on the direct voltage from the switching power supply isolation driving module; the controller is configured to receive link level driving voltage information from each of the one or more lamp bead driving chips through a single wire bus, and send a boost feedback control signal or a buck feedback control signal to the LED driving voltage adjusting module based on the received link level driving voltage information, so as to cause the LED driving voltage adjusting module to boost adjust the LED driving voltage based on the boost feedback control signal or to buck adjust the LED driving voltage based on the buck feedback control signal, wherein: each of the one or more lamp bead driving chips comprises one or more LED channels, and the link level driving voltage information of each of the one or more lamp bead driving chips comprises information indicating a number of lamp bead driving chips in the lamp bead driving chip that need the LED driving voltage to be boosted, bucked, or unchanged, or information indicating a number of LED channels in the lamp bead driving chip that need the LED driving voltage to be boosted, bucked, or unchanged. In each of the one or more lamp bead driving chips, adjacent lamp bead driving chips are arranged in a series connection mode of signal output ports and signal input ports. Each of the one or more lamp bead driving chips is configured to determine whether the LED driving voltage meets a predetermined requirement according to a negative terminal voltage of a LED lamp bead connected to any one of the LED channels when the LED channel is turned on. Each of the one or more lamp bead driving chips is further configured to: determine that the LED driving voltage is too low and needs to be boosted accordingly when the negative terminal voltage of the LED lamp bead is detected to be lower than a set voltage corresponding to the predetermined requirement; determine that the LED driving voltage is too high and needs to be bucked accordingly when the negative terminal voltage of the LED lamp bead is detected to be higher than the set voltage; and determine that the LED driving voltage does not need to be changed when the negative terminal voltage of the LED lamp bead is detected to be equal to the set voltage. Each of the one or more lamp bead driving chips is further configured to: determine whether the LED driving voltage meets the predetermined requirement at different time periods for different LED channels in the lamp bead driving chip. ​ ​ ​ ​ 2. The LED lamp bead driving system according to claim 1, wherein, ​ 3. The LED lamp bead driving system according to claim 1, wherein, ​ 4. The LED lamp bead driving system according to claim 3, wherein, ​ ​ ​ ​ ​ 5. The LED lamp bead driving system according to claim 3, wherein, ​ ​ 6. The LED lamp bead driving system according to claim 3, wherein, Each of the one or more lamp bead driving chips is further configured to aggregate pieces of channel-level driving voltage information indicating whether each LED channel therein needs the LED driving voltage to be lowered, raised, or unchanged to obtain chip-level driving voltage information, receive the link-level driving voltage information from a previous stage lamp bead driving chip, add the chip-level driving voltage information to the link-level driving voltage information by performing a logical operation on the link-level driving voltage information and the chip-level driving voltage information, and then send the link-level driving voltage information to a next stage lamp bead driving chip or the processor.

7. The LED lamp bead driving system according to claim 6, wherein, The chip-level driving voltage information contains information indicating one or more of a number of LED channels in the lamp bead driving chip that need the LED driving voltage to be raised, a number of LED channels that need the LED driving voltage to be lowered, and a number of LED channels that need the LED driving voltage to be unchanged.

8. The LED lamp bead driving system according to claim 6, wherein, The chip-level driving voltage information contains information indicating whether the lamp bead driving chip needs the LED driving voltage to be raised, lowered, or unchanged.

9. The LED lamp bead driving system according to claim 1, wherein, The controller is configured to determine, based on the received link-level driving voltage information, whether each control region controlled thereby needs the LED driving voltage to be raised, lowered, or unchanged, and send the voltage-raising feedback control signal or the voltage-lowering feedback control signal to the LED driving voltage adjustment module according to a number of control regions controlled thereby that need the LED driving voltage to be raised, lowered, or unchanged, wherein the controller has one or more control regions, and each control region includes one or more lamp bead driving chips.

10. The LED lamp bead driving system according to claim 1, wherein, The controller is configured to determine, based on the received link-level driving voltage information, a number of lamp bead driving chips controlled thereby that need the LED driving voltage to be raised, lowered, or unchanged, or a number of LED channels in the lamp bead driving chips controlled thereby that need the LED driving voltage to be raised, lowered, or unchanged, and send the voltage-raising feedback control signal or the voltage-lowering feedback control signal to the LED driving voltage adjustment module according to the number of lamp bead driving chips controlled thereby that need the LED driving voltage to be raised, lowered, or unchanged, or the number of LED channels in the lamp bead driving chips controlled thereby that need the LED driving voltage to be raised, lowered, or unchanged.

11. The LED lamp bead driving system according to claim 1, wherein, The switch power supply isolation driving module includes a switch power supply module with a fixed voltage output.

12. The LED lamp bead driving system according to claim 1, wherein, The LED driving voltage adjustment module includes a DC / DC power supply module in a DC / DC architecture.

13. The LED lamp bead driving system according to claim 1, wherein, The controller is configured to send the voltage-raising feedback control signal or the voltage-lowering feedback control signal to the LED driving voltage adjustment module through a single-wire communication protocol. The controller is configured to send the voltage-raising feedback control signal or the voltage-lowering feedback control signal to the LED driving voltage adjustment module through a single-wire communication protocol.

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