LED driving data serial transmission method, LED driving device and system

Abstract

This invention discloses a method, device, and system for serial transmission of LED driving data. The method involves an initial LED driving device receiving at least one input signal. Subsequent LED driving modules sequentially acquire the output signals of preceding LED driving modules. Each module retrieves its own driving data from the input signals based on its address and outputs a single output signal. The method also allows for signal quality assessment of the driving data acquired from each input port, forwarding the high-quality input signals to subsequent LED driving devices. This invention eliminates the need for an external clock signal and avoids the need to first intercept the driving data required by the front-end LED driving modules before shaping and forwarding the remaining data. This reduces the hardware overhead of internal data processing in the LED driving device, increases the upper limit of data transmission frequency, and minimizes the impact of the LED driving device on the output signal quality.

Description

Technical Field

[0001] The present invention relates to the field of LED display technology, and in particular to an LED drive data serial transmission method, an LED drive device and a system. Background Art

[0002] In the current serial transmission method of LED driving data, a signal transmission link with a clock signal or a signal transmission link without a clock signal is usually used.

[0003] In the serial transmission method of LED driving data with a clock signal, the LED driving device latches the signal at the data input end according to the clock signal, selects the latched data along the normal line as the display driving data of the LED driving device to control the LED driving port out1-outn (i.e., driving port 1-driving port n), and sends the data from the data output end data_out according to the clock signal; in the serial transmission method of LED driving data without a clock signal, in order to avoid the data output from relying on the external clock signal, the LED driving module will first intercept the front-end data of the input signal before forwarding the data, and use the front-end data as the driving data required by itself, and then send the remaining data through the output port. In this way, in order to intercept the input signal, the LED driving module must first allow the input signal to enter the internal signal processing module of the LED driving device, and the internal hardware has different driving capabilities for the rising edge and falling edge of the signal, so that the input signal will be clipped after being processed by the internal device. In order to solve the problem of output signal clipping, the LED driving device must have a built-in signal shaping module to shape the waveform of the processed input signal to ensure that the subsequent chip can receive high-quality signals.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a method for serial transmission of LED driving data, an LED driving device and a system, so as to solve the problem that in the existing method for serial transmission of LED driving data, a clock signal is needed to latch the signal at the data input end or the input signal is clipped due to interception of the input signal.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a method for transmitting LED driving data in series, which is used in a system having a plurality of LED driving devices connected in series, wherein the LED driving devices have a plurality of input ports, and the method for transmitting LED driving data in series comprises the steps of:

[0008] The initial LED driving device receives at least one input signal, obtains current-level driving data from the input signal according to its own address, and outputs an output signal; wherein the data content of the input signal includes driving data and address data;

[0009] The LED driving devices at the rear stage sequentially obtain the output signals of the LED driving devices at the front stage as input signals, and obtain the driving data of the current stage from the input signals according to their own addresses;

[0010] Perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality;

[0011] The input signal obtained from the input port with good quality is forwarded to the subsequent LED driving device, and the LED is driven for display according to the driving data.

[0012] According to a further configuration of the present invention, the steps of the initial LED driving device receiving at least one input signal, obtaining current-stage driving data from the input signal according to its own address and outputting one output signal include:

[0013] After receiving a complete frame of address-related data, the input port of the LED driver sets its own address according to the received address-related data;

[0014] The new address data is sent out through the output port, so that the address data is transmitted step by step according to the connection sequence of the LED driving devices until the addresses of all the LED driving devices are sorted.

[0015] According to a further configuration of the present invention, the step of judging the signal quality of the driving data obtained from each input port to identify the input port with good signal quality includes:

[0016] Detect whether each input port has a signal input, and confirm the input port with a signal input as an input port with good quality;

[0017] When it is detected that each input port has a signal input, the number of data frames of the input signal connected to each input port in the same time period is counted and compared, and the input port with good signal quality is obtained according to the comparison result.

[0018] According to a further configuration of the present invention, the step of driving the LED to display according to the driving data comprises:

[0019] Converting the driving data into LED data;

[0020] The LED data is converted into a pulse width modulation signal and output to a switch tube connected to the LED to drive the LED for display.

[0021] According to a further configuration of the present invention, after the number of signal paths of the input ports of all LED driving devices meets the requirement, or when no preceding LED driving device outputs a signal, the input signal transmission is completed.

[0022] In a second aspect, the present invention provides an LED driving device based on the LED driving data serial transmission method as described above, which comprises: a plurality of input ports, an output port, a signal processing module, an input selection module and a display driving module; wherein,

[0023] The input port is used to receive an input signal;

[0024] The signal processing module is connected to the input port and is used to judge the signal quality of the driving data obtained by each input port to confirm the input port with good signal quality;

[0025] The input selection module is connected to the signal processing module and the input port respectively, and is used to forward the input signal obtained by the input port with good quality to the subsequent LED driving device according to the switching instruction output by the signal processing module;

[0026] The display driving module is connected to the signal processing module and is used to drive the LED to display according to the driving data.

[0027] According to a further configuration of the present invention, the signal processing module comprises: a data extraction circuit, a signal quality determination circuit, a buffer and an address sending circuit; wherein,

[0028] The data extraction circuit is connected to the input port and is used to extract the data content and signal characteristics of the input port; wherein the data content includes drive data and address data, and the signal characteristics include the presence or absence of a signal and the type of data content;

[0029] The buffer is connected to the data extraction circuit and is used to store the drive data and the address data;

[0030] The signal quality judgment circuit is connected to the data extraction circuit and the buffer respectively, and is used to confirm the input port with good signal quality according to the input signals of each input port, and output a corresponding switching instruction;

[0031] The address sending circuit is connected to the buffer and is used for sorting the address data.

[0032] According to a further configuration of the present invention, the input selection module comprises: a selector, an instruction decoder and a signal latch; wherein,

[0033] The instruction decoder is connected to the signal processing module and is used to convert the switching instruction into a gating control signal;

[0034] The signal latch is connected to the instruction decoder and the selector respectively, and is used to latch the gating control signal;

[0035] The selector is connected to the input port and is used to select an input port according to the selection control signal and the address data path;

[0036] The display driving module includes: a decoding driving circuit, a pulse width modulation signal generating circuit and a plurality of switch tubes; wherein,

[0037] The decoding driving circuit is connected to the signal processing module and is used to convert the driving data into LED data;

[0038] The pulse width modulation signal generating circuit is connected to the decoding driving circuit and the switch tube respectively, and is used to convert the LED data into a pulse width modulation signal and output it to the switch tube, so as to control the switch tube to drive the LED for display.

[0039] According to a further configuration of the present invention, the signal quality determination circuit comprises:

[0040] Frame number detector, timer and frame number comparator; wherein,

[0041] The frame number detector is connected to the input port and the timer respectively, and is used to count the number of data frames received by all input ports during the enabling period;

[0042] The frame number comparator is connected to the frame number detector and is used to compare the number of data frames received by all input ports and select the input ports with good signal quality according to the comparison result;

[0043] The timer is connected to the frame number detector and the frame number comparator respectively, and is used to provide a detection enable signal for the frame number detector and a comparison enable signal for the frame number comparator.

[0044] In a third aspect, the present invention provides an LED driving system, which includes a plurality of LED driving devices as described above, wherein the plurality of LED driving devices are connected in series.

[0045] The present invention provides a method, an LED driving device and a system for serial transmission of LED driving data. The present invention connects at least one input signal through the initial LED driving device, obtains the current driving data from the input signal according to its own address and outputs an output signal, and then the subsequent LED driving device respectively obtains the output signal of the front LED driving device in sequence as the input signal, and obtains the current driving data from the input signal according to its own address, and then performs signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality, and finally forwards the input signal obtained from the input port with good quality to the subsequent LED driving device, and drives the LED to display according to the driving data. In this way, the present invention connects at least one input signal through the initial LED driving device, wherein each of the other LED driving modules after the initial LED driving module respectively obtains the output signal of the previous LED driving module in sequence, obtains the current driving data from the input signal according to its own address and outputs an output signal, and can perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality, and forwards the input signal obtained from the input port with good quality to the subsequent LED driving device. Compared with the prior art, the present invention does not need to rely on an external clock signal, nor does it need to first intercept the driving data required by the front-end LED driving module and then shape and forward the remaining data. This can reduce the hardware overhead of the LED driving device for internal data processing, while increasing the upper frequency limit of data transmission and reducing the impact of the LED driving device on the output signal quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0047] Figure 1 It is a flow chart of the LED driving data serial transmission method in the present invention.

[0048] Figure 2 It is a principle block diagram of the LED drive data serial transmission system in the present invention.

[0049] Figure 3 It is a schematic diagram of a LED driving device in one embodiment of the present invention, in which the LED driving device extracts current-stage driving data from an input signal according to its own address to drive the LED.

[0050] Figure 4 It is a schematic diagram of address sorting for redundant LED driving devices in one embodiment of the present invention.

[0051] Figure 5 It is a schematic diagram of addressing two LED driving devices as a group in one embodiment of the present invention.

[0052] Figure 6 It is a schematic diagram of the LED driving device in the present invention.

[0053] Figure 7 1 is a waveform diagram of input signals and output signals in one embodiment of the present invention.

[0054] Figure 8 It is a circuit schematic diagram of a signal processing module in one embodiment of the present invention.

[0055] Fig. 9 1 is a circuit schematic diagram of a signal quality judgment circuit in one embodiment of the present invention.

[0056] Fig.10 It is a circuit schematic diagram of an input selection module in one embodiment of the present invention.

[0057] Fig.11 It is a circuit schematic diagram of a display driving module in one embodiment of the present invention.

[0058] The marks in the accompanying drawings are: 100, signal processing module; 110, data extraction circuit; 120, signal quality judgment circuit; 121, frame number detector; 122, timer; 123, frame number comparator; 130, buffer; 140, address sending circuit; 200, input selection module; 210, selector; 220, instruction decoder; 230, signal latch; 300, display driving module; 310, decoding driving circuit; 320, pulse width modulation signal generating circuit. DETAILED DESCRIPTION

[0059] The present invention provides a LED driving data serial transmission method, an LED driving device and a system. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0060] In the embodiments and the scope of the patent application, unless the text specifically defines the article, "a", "an", "the" and "the" may also include plural forms. If there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0061] It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when an element is said to be "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can be intermediate elements. In addition, the "connection" or "coupling" used herein can include wireless connection or wireless coupling. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0062] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as herein.

[0063] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0064] The inventor has found that in the serial transmission method of LED driving data with a clock signal, the LED driving device latches the signal at the data input end according to the clock signal, selects the latched data along the normal line as the display driving data of the LED driving device to control the LED driving port out1-outn, and sends the data from the data output end data_out according to the clock signal; in the serial transmission method of LED driving data without a clock signal, in order to avoid the data output from being dependent on the external clock signal, the LED driving module will first intercept the front-end data of the input signal before forwarding the data, and use the front-end data as the driving data required by itself, and then send the remaining data through the output port. Therefore, in the current serial transmission method of LED driving data, either the data output depends on the external clock signal, or the data needs to be intercepted, and the input signal needs to be shaped. In addition, if the data is intercepted, it can only be displayed continuously in sequence, and multiple display modes cannot be used. It can only be displayed continuously in sequence. That is to say, before inputting the signal each time, the LED driver module intercepts the driving data according to the connection order of the LED driver modules in the signal series link, so that all the LED driver modules on the link can display unique driving data in sequence.

[0065] In view of the above technical problems, the present invention provides a method for transmitting LED driving data in series, an LED driving device and a system, wherein at least one input signal is connected through the starting LED driving device, wherein each of the other LED driving modules after the starting LED driving module respectively obtains the output signal of the previous LED driving module in sequence, obtains the current driving data from the input signal according to its own address and outputs an output signal, and can perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality, and forward the input signal obtained from the input port with good quality to the subsequent LED driving device. Compared with the prior art, the present invention does not need to rely on an external clock signal, nor does it need to first intercept the driving data required by the front-end LED driving module, and then reshape and forward the remaining data, which can reduce the hardware overhead of the LED driving device for internal data processing, while increasing the upper limit of the frequency of data transmission, and reducing the impact of the LED driving device on the output signal quality. In addition, different address writing methods can be performed on the LED driving device to perform different display methods, thereby expanding the application scenarios of the redundant serial LED driving device.

[0066] Please also see Figures 1 to 4 The present invention provides a preferred embodiment of a LED driving data serial transmission method.

[0067] In some embodiments, Figure 1 , Figure 2 and Figure 3 As shown, the present invention provides a method for transmitting LED driving data in series, which is used in a system having a plurality of LED driving devices connected in series, wherein the LED driving devices have a plurality of input ports, and the method for transmitting LED driving data in series comprises the steps of:

[0068] S100, the starting LED driving device receives at least one input signal, obtains current-level driving data from the input signal according to its own address, and outputs one output signal; wherein the data content of the input signal includes driving data and address data;

[0069] S200, the LED driving devices at the rear stage sequentially obtain the output signals of the LED driving devices at the front stage as input signals, and obtain the driving data of the current stage from the input signals according to their own addresses;

[0070] S300, judging the signal quality of the driving data obtained from each input port to confirm the input port with good signal quality;

[0071] S400: forwarding the input signal obtained from the input port with good quality to the subsequent LED driving device, and driving the LED for display according to the driving data.

[0072] In this embodiment, a plurality of LED driving devices are connected in series, and each LED driving device has at least two input ports (such as Figure 2 1 and 2), and has an output port (such as Figure 2 The output in the LED driver). The starting LED driver receives at least one input signal from the signal source, wherein each of the other LED driver modules after the starting LED driver module respectively obtains the output signal of the previous LED driver module in sequence, obtains the current-stage driving data from the input signal according to its own address and outputs one output signal, and can perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality, and forward the input signal obtained from the input port with good quality to the next-stage LED driver. At the same time, the LED of the corresponding LED driver device at this stage can be displayed according to the driving data of the LED driver device at this stage. When the number of signal paths of each input port of all LED driver devices meets the requirements, or when there is no output signal from the previous-stage LED driver device, the input signal transmission is completed.

[0073] Compared with the prior art, the present invention does not need to rely on an external clock signal, nor does it need to first intercept the driving data required by the front-end LED driver module and then reshape and forward the remaining data. This can reduce the hardware overhead of the LED driver for internal data processing and increase the upper frequency limit of data transmission. Since the output signal does not need to be shaped or re-encoded by an internal clock or an external clock, the data content and length of the output signal are consistent with the input signal during signal transmission, reducing the impact of the LED driver on the quality of the output signal. In addition, different address writing methods can be used for the LED driver to perform different display methods, thereby expanding the application scenarios of redundant series-connected LED driver devices.

[0074] In some embodiments, the steps of the initial LED driving device receiving at least one input signal, obtaining current-stage driving data from the input signal according to its own address and outputting an output signal include:

[0075] S110, after receiving a complete frame of address-related data, the input port of the LED driving device sets its own address according to the received address-related data;

[0076] S120, sending out the new address data through the output port, so that the address data is transmitted step by step according to the connection sequence of the LED driving devices, until the addresses of all the LED driving devices are sorted.

[0077] In this embodiment, when the first LED driver receives an input signal (with address-related data), it is necessary to sort the addresses of the redundant series-connected LED driver devices so that each LED driver device has an independent address. After the LED driver receives the input signal, the first LED driver starts to forward the address data step by step. Specifically, when the LED driver receives the address-related data, it disconnects the connection between the output port and the input port from inside the LED driver device, and does not send data during the address data reception period. After receiving a complete frame of address-related data, the LED driver device will first set its own address, and then send the new address data through the output port, so that the address data can only be transmitted from the beginning to the end according to the number of LED driver devices in the order of connection of the LED driver devices, and finally complete the sorting of the addresses of all LED driver devices, such as Figure 4 It should be noted that there are many ways to sort the addresses of the LED driving device, which can be ordered or disordered.

[0078] Furthermore, in this example, when the LED driving devices are connected in series, two LED driving devices are grouped together (eg Figure 5The LED driver device 1 and LED driver device 2 in the address sequence are compiled so that each adjacent two LED driver devices can obtain the same driving data, so that the n segments of data (data 1, data 2, data n) sent by the signal source can drive 2n LED driver devices, such as Figure 5 It is understandable that the present invention can also perform address compilation with n (n is greater than or equal to 2) or more LED driving devices as a group, or perform reverse address compilation, etc.

[0079] In some embodiments, the step of judging the signal quality of the driving data obtained from each input port to identify the input port with good signal quality includes:

[0080] S310, detecting whether each input port has a signal input, and identifying an input port with a signal input as an input port with good quality;

[0081] S320: When it is detected that each input port has a signal input, the number of data frames of the input signal received by each input port in the same time period is counted and compared, and the input port with good signal quality is obtained according to the comparison result.

[0082] In this embodiment, the LED driving device determines the signal quality of the input signals of each redundant input port, selects the input port with good signal quality as the data receiving port, and directly connects the input port with good signal quality to the input port to forward the driving data backward.

[0083] like Figure 2 As shown, taking two input ports (input 1 and input 2) as an example, the LED driving device uses the input port of the first input signal by default for data reception and transmission. When receiving the input signals of the two input ports at the same time to judge the signal quality, if one input port has a signal input and the other input port has no signal input, then the port with the signal input is judged to be the input port with good quality. If both input ports have signal input, the number of data frames of the input signals connected to each input port in the same time period is counted and compared, and the input port with good signal quality is obtained according to the comparison result, specifically, the input port with the largest number of data frames after the timing time ends is used as the input port with good signal quality. If there are multiple input ports with the same number of data frames and the largest number of data frames, the input port with the highest number is selected in the order of the input port with the largest number of data frames. For example, when there are input ports 1 and 2, input port 1 is used as the input port with good signal quality. Finally, a switching instruction is output to the input selection module 200 according to the comparison result to select the input port.

[0084] In some embodiments, the step of driving the LED to display according to the driving data includes:

[0085] S410, converting the driving data into LED data;

[0086] S420, converting the LED data into a pulse width modulation signal and outputting it to a switch tube connected to the LED to drive the LED for display.

[0087] In this embodiment, the LED driving device at each level converts the driving data received by the input port with good signal quality selected by it into LED data. The LED driving device can further convert the LED data into a pulse width modulation (PWM) signal for controlling the switch tube connected to the LED to realize driving and displaying the LED.

[0088] In some embodiments, Figure 6 As shown, the present invention provides an LED driving device based on the LED driving data serial transmission method as described above, which includes: a plurality of input ports, an output port, a signal processing module 100, an input selection module 200 and a display driving module 300. The input port is used to receive an input signal; the signal processing module 100 is connected to the input port, and is used to perform signal quality judgment on the driving data obtained by each input port to confirm the input port with good signal quality; the input selection module 200 is respectively connected to the signal processing module 100 and the input port, and is used to forward the input signal obtained by the input port with good quality to the subsequent LED driving device according to the switching instruction output by the signal processing module 100; the display driving module 300 is connected to the signal processing module 100, and is used to drive the LED to display according to the driving data.

[0089] In this embodiment, a plurality of LED driving devices are connected in series, each LED driving device has at least two input ports and one output port, and all input ports of the LED driving device are sequentially connected to the output signal of the previous LED driving device. The starting LED driving module inputs at least one LED driving data channel, and each of the other LED driving modules after the starting LED driving module sequentially obtains the output signal of the previous LED driving module, until the number of redundant input signal channels of each LED driving module meets the requirements. For example, Figure 2 When there are three LED driver devices, if the LED driver device has two signal input ports, the input port names are input 1 and input 2, then the input 1 of the second LED driver device is connected to the output port of the first LED driver device (i.e. Figure 2The output of the second LED driver device is connected to the output of the signal source, the input 1 of the third LED driver device is connected to the output of the second LED driver device, and the input 2 of the third LED driver device is connected to the output of the first LED driver device; if the LED driver device has 3 signal input ports, and the port names are input 1, input 2, and input 3, then the input 1 of the third LED driver device is connected to the output of the second LED driver device, the input 2 of the third LED driver device is connected to the output of the first LED driver device, and the input 3 of the third LED driver device is connected to the output of the signal source.

[0090] When the starting LED driving device receives at least one input signal, each of the other LED driving modules after the starting LED driving module sequentially obtains the output signal of the previous LED driving module, and the signal processing module 100 can obtain the current level driving data from the input signal according to the LED driving device's own address and output an output signal, and can perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality. The input selection module 200 can forward the input signal obtained from the input port with good quality to the next level LED driving device according to the switching instruction output by the signal processing module 100, and at the same time, the display driving module 300 can display the LED of the corresponding LED driving device of this level according to the driving data of the LED driving device of this level.

[0091] It can be seen that the present invention does not need to rely on an external clock signal, nor does it need to first intercept the driving data required by the front-end LED driving module and then reshape and forward the remaining data, which can reduce the hardware overhead of the LED driving device for internal data processing, while increasing the upper limit of the frequency of data transmission and reducing the impact of the LED driving device on the output signal quality. Figure 7 In addition, different address writing modes can be performed on the LED driving device to perform different display modes, thereby expanding the application scenarios of the redundant series-connected LED driving device.

[0092] In some embodiments, Figure 6 and Figure 8As shown, the signal processing module 100 includes: a data extraction circuit 110, a signal quality judgment circuit 120, a buffer 130 and an address sending circuit 140. The data extraction circuit 110 is connected to the input port and is used to extract the data content and signal characteristics of the input port; the data content includes drive data and address data, and the signal characteristics include the presence or absence of a signal and the type of data content; the buffer is connected to the data extraction circuit 110 and is used to store the drive data and the address data; the signal quality judgment circuit 120 is respectively connected to the data extraction circuit 110 and the buffer, and is used to confirm the input port with good signal quality according to the input signal of each input port, and output a corresponding switching instruction; the address sending circuit 140 is connected to the buffer 130 and is used to sort the address data.

[0093] In this embodiment, the data extraction circuit 110 can extract the data content and signal characteristics of the input signal of each input port. The address sending circuit 140 can sort the address data in the buffer 130 and send it to the input selection module 200 through the address data path. The signal quality judgment circuit 120 can output the corresponding switching instruction to the input selection module 200 according to the signal characteristics of each input port. Taking two input ports as an example, during the data transmission process, when address data is received, a switching instruction for switching the output channel to the address data path is issued; when driving data is received, a switching instruction is output according to the signal characteristics of the two input ports (input 1 signal characteristics and input 2 signal characteristics). If one input port has a signal input and the other port has no signal input, then the port with a signal input is judged to be an input port with good quality; if both signal input ports have data, the number of data frames of the input signal connected to each input port in the same time period is counted and compared, and the input port with good signal quality is obtained according to the comparison result, specifically, the input port with the largest number of data frames after the timing time ends is taken as the input port with good signal quality. If there are multiple input ports with the same number of data frames and the largest number of data frames, the input port with the earliest serial number is selected in the order of the input port with the largest number of data frames, and a switching instruction for switching to the input port with good signal quality is issued to the input selection module 200 accordingly, and the input selection module 200 can select the input port with good quality to be turned on.

[0094] Furthermore, if Fig. 9As shown, the signal quality judgment circuit 120 includes: a frame number detector 121, a timer 122 and a frame number comparator 123. The frame number detector 121 is connected to the input port and the timer 122 respectively, and is used to count the number of data frames received by all input ports during the enable period; the frame number comparator 123 is connected to the frame number detector 121, and is used to compare the number of data frames received by all input ports, and filter out input ports with good signal quality according to the comparison result; the timer 122 is connected to the frame number detector 121 and the frame number comparator 123 respectively, and is used to provide a detection enable signal to the frame number detector 121, and provide a comparison enable signal to the frame number comparator 123.

[0095] In this embodiment, the signal output by the data extraction circuit 110 will enter the frame number detector 121, and the timer 122 will send a detection enable signal to the frame number detector 121 during the timing period, and will send a comparison enable signal to the frame number comparator 123 after the timing ends. Taking two input ports as an example, after the two signals output by the data extraction circuit 110 enter the frame number detector 121, the number of data frames received by the two input ports can be counted during the enable period according to the signal characteristics of the two signals (input 1 signal characteristics and input 2 signal characteristics). After the timing ends, the frame number comparator 123 can compare the number of data frames received by the two input ports, and use the input port with more data frames as the port with good signal quality. If the number of data frames of the two input ports is the same, the input port 1 with the front order is used as the input port with better signal quality. Finally, according to the comparison result, a switching instruction is output to the input selection module 200 to select the input port.

[0096] In some embodiments, Fig.10 As shown, the input selection module 200 includes: a selector 210, an instruction decoder 220 and a signal latch 230. The instruction decoder 220 is connected to the signal processing module 100, and is used to convert the switching instruction into a gating control signal; the signal latch 230 is connected to the instruction decoder 220 and the selector 210 respectively, and is used to latch the gating control signal; the selector 210 is connected to the input port, and is used to gating an input port according to the gating control signal and the address data path.

[0097] In this embodiment, the selector 210 may be a 3-to-1 selector 210, the input end of the selector 210 has three data paths, wherein input 1 and input 2 are external signal input ports, the third data path is an address data path, i.e., an internal address signal output port of the selector 210, and the output end of the selector 210 is used to output a signal. The instruction decoder 220 is connected to the signal quality judgment circuit 120, and can convert the received switching instruction into a control signal of the selector 210. The signal latch 230 is used to latch the control signal of the selector 210 to select one of the three input ports of the selector 210.

[0098] In some embodiments, Fig.11 As shown, the display driving module 300 includes: a decoding driving circuit 310, a pulse width modulation signal generating circuit 320 and a plurality of switch tubes; wherein the decoding driving circuit 310 is connected to the signal processing module 100, and is used to convert the driving data into LED data; the pulse width modulation signal generating circuit 320 is respectively connected to the decoding driving circuit 310 and the switch tube, and is used to convert the LED data into a pulse width modulation signal and output it to the switch tube, so as to control the switch tube to drive the LED for display.

[0099] In this embodiment, the anode of the LED (LED1, LED2, LED3) is connected to the power supply voltage VLED through the power supply, and the cathode of the LED is connected to the switch tube (such as Fig.11 The decoding driving circuit 310 can convert the driving data into individual LED data (LED1 data, LED2 data, LED3 data), and provide them to the pulse width modulation signal generating circuit 320. The pulse width modulation signal generating circuit 320 converts the LED data into a pulse width modulation signal for output, so as to control the switch tube connected to the LED to drive the LED for display.

[0100] In some embodiments, the present invention provides an LED driving system, which includes a plurality of LED driving devices as described above, and the plurality of LED driving devices are connected in series. Specific details are as described in an embodiment of an LED driving device, which will not be repeated here.

[0101] In summary, the LED driving data serial transmission method, LED driving device and system provided by the present invention have the following beneficial effects:

[0102] There is no need to rely on external clock signals, nor is there any need to first intercept the driving data required by the front-end LED driver module and then reshape and forward the remaining data. This can reduce the hardware overhead of the LED driver for internal data processing, while increasing the upper limit of the frequency of data transmission and reducing the impact of the LED driver on the output signal quality.

[0103] Different address writing modes can be performed on the LED driving device to perform different display modes, thereby expanding the application scenarios of the redundant series-connected LED driving device.

[0104] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for transmitting LED driving data in series, used in a system having a plurality of LED driving devices connected in series, wherein the LED driving devices have a plurality of input ports, characterized in that: The LED driving data serial transmission method comprises the following steps: The initial LED driving device receives at least one input signal, obtains current-level driving data from the input signal according to its own address, and outputs an output signal; wherein the data content of the input signal includes driving data and address data; The steps of the initial LED driving device receiving at least one input signal, obtaining current-stage driving data from the input signal according to its own address and outputting an output signal include: After receiving a complete frame of address-related data, the input port of the LED driver sets its own address according to the received address-related data; wherein, when the first LED driver receives the input signal, the addresses of the redundant LED driver devices connected in series are sorted so that each LED driver device has an independent address; The new address data is sent out through the output port, so that the address data is transmitted step by step according to the connection sequence of the LED driver devices until the addresses of all the LED driver devices are sorted; The LED driving devices at the rear stage sequentially obtain the output signals of the LED driving devices at the front stage as input signals, and obtain the driving data of the current stage from the input signals according to their own addresses; Perform signal quality judgment on the driving data obtained from each input port to confirm the input port with good signal quality; The input signal obtained from the input port with good quality is forwarded to the subsequent LED driving device, and the LED is driven for display according to the driving data.

2. The LED driving data serial transmission method according to claim 1, characterized in that: The step of judging the signal quality of the driving data obtained from each input port to identify the input port with good signal quality includes: Detect whether each input port has a signal input, and confirm the input port with a signal input as an input port with good quality; When it is detected that each input port has a signal input, the number of data frames of the input signal connected to each input port in the same time period is counted and compared, and the input port with good signal quality is obtained according to the comparison result.

3. The LED driving data serial transmission method according to claim 1, characterized in that: The step of driving the LED to display according to the driving data comprises: Converting the driving data into LED data; The LED data is converted into a pulse width modulation signal and output to a switch tube connected to the LED to drive the LED for display.

4. The LED driving data serial transmission method according to claim 1, characterized in that: When the number of signal paths of each input port of all LED driving devices meets the requirement, or when no preceding LED driving device outputs a signal, the input signal transmission is completed.

5. An LED driving device based on the LED driving data serial transmission method according to any one of claims 1 to 4, characterized in that: include: Several input ports, output ports, signal processing modules, input selection modules and display driver modules; wherein, The input port is used to receive an input signal; The signal processing module is connected to the input port and is used to judge the signal quality of the driving data obtained by each input port to confirm the input port with good signal quality; The input selection module is connected to the signal processing module and the input port respectively, and is used to forward the input signal obtained by the input port with good quality to the subsequent LED driving device according to the switching instruction output by the signal processing module; The display driving module is connected to the signal processing module and is used to drive the LED to display according to the driving data.

6. The LED driving device according to claim 5, characterized in that: The signal processing module includes: a data extraction circuit, a signal quality judgment circuit, a buffer and an address sending circuit; wherein, The data extraction circuit is connected to the input port and is used to extract the data content and signal characteristics of the input port; wherein the data content includes drive data and address data, and the signal characteristics include the presence or absence of a signal and the type of data content; The buffer is connected to the data extraction circuit and is used to store the drive data and the address data; The signal quality judgment circuit is connected to the data extraction circuit and the buffer respectively, and is used to confirm the input port with good signal quality according to the input signals of each input port, and output a corresponding switching instruction; The address sending circuit is connected to the buffer and is used for sorting the address data.

7. The LED driving device according to claim 5, characterized in that: The input selection module includes: a selector, an instruction decoder and a signal latch; wherein, The instruction decoder is connected to the signal processing module and is used to convert the switching instruction into a gating control signal; The signal latch is connected to the instruction decoder and the selector respectively, and is used to latch the gating control signal; The selector is connected to the input port and is used to select an input port according to the selection control signal and the address data path; The display driving module includes: a decoding driving circuit, a pulse width modulation signal generating circuit and a plurality of switch tubes; wherein, The decoding driving circuit is connected to the signal processing module and is used to convert the driving data into LED data; The pulse width modulation signal generating circuit is connected to the decoding driving circuit and the switch tube respectively, and is used to convert the LED data into a pulse width modulation signal and output it to the switch tube, so as to control the switch tube to drive the LED for display.

8. The LED driving device according to claim 6, characterized in that: The signal quality judgment circuit includes: a frame number detector, a timer and a frame number comparator; wherein, The frame number detector is connected to the input port and the timer respectively, and is used to count the number of data frames received by all input ports during the enabling period; The frame number comparator is connected to the frame number detector and is used to compare the number of data frames received by all input ports and select the input ports with good signal quality according to the comparison result; The timer is connected to the frame number detector and the frame number comparator respectively, and is used to provide a detection enable signal for the frame number detector and a comparison enable signal for the frame number comparator.

9. An LED driving system, characterized in that: It comprises a plurality of LED driving devices as described in any one of claims 5 to 7, wherein the plurality of LED driving devices are connected in series.

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