CN111867177B

CN111867177B - LED driving apparatus and method, and readable storage medium

Info

Publication number: CN111867177B
Application number: CN202010668261.6A
Authority: CN
Inventors: 周盛; 蔡鹏飞; 丁东民; 梁丽兰; 赵阳; 刘珍利; 刘斯达; 乃瑜; 施丽
Original assignee: CRM ICBG Wuxi Co Ltd
Current assignee: CRM ICBG Wuxi Co Ltd
Priority date: 2020-07-13
Filing date: 2020-07-13
Publication date: 2024-06-14
Anticipated expiration: 2040-07-13
Also published as: CN111867177A

Abstract

The invention discloses an LED driving device and method and a readable storage medium. One embodiment of the device comprises a reset module which outputs a reset signal when detecting that an nth data driving signal output by an (N-1) th LED driving device has an input pulse width; the signal counting module counts the input (N-1) stage data driving signals when the reset signals are not received, and outputs a mark signal when the number of bits required by driving the (N-1) stage LED driving device is counted; the signal selection module is used for selecting the input (N-1) -th data driving signal as a data driving signal to be demodulated when receiving the marking signal; and a signal demodulation module. The device of the embodiment can finish the reconstruction of the serial communication link of the LED lamp string at one time under the condition that the (N-1) th stage driving device is damaged, and simultaneously finish the LED driving of the lamp string correctly.

Description

LED driving apparatus and method, and readable storage medium

Technical Field

The invention relates to the technical field of power supplies. And more particularly, to an LED driving apparatus and method and a readable storage medium.

Background

In application projects such as outdoor landscape lighting and auxiliary lighting, low-power LED chips are widely applied. The LED light string and the LED external wall display screen manufactured by the LED light string according to a preset rule are used for displaying various patterns and character information. The basic pixel point of the display screen with the LED light string and the LED light string combination is generally composed of one driving chip and three or four LED chips. The driving chip of each pixel point takes the role of LED driving and the role of reconstructing the control signal forwarded by the driving chip of the last basic pixel point, so that the control information is forwarded to the next driving chip one by one from one end of the light string in a serial communication mode until the last one.

According to the conventional LED string driving system illustrated in fig. 1, it has only one signal input terminal DIN and one signal transfer output terminal DO. When one or a discontinuous plurality of driving chips in such a string of lights are damaged, for example when the chip U2 is damaged, the first damaged driving chip is not lit up any more at the position where the first damaged driving chip appears, and the U2 forwarding output DO will not be able to output the input signal D3 which will drive the next stage of basic pixels. Such a damaged chip or pixel composed of it is called a "dead pixel". When a defective pixel occurs in the circuit, the defective pixel and the LEDs after the defective pixel cannot be normally driven, namely, the driving of the subsequent LEDs cannot be timely reconstructed while the defective pixel is found, but the defective pixel must be replaced again and the LED main controller must wait for sending out second frame data, so that the LED light string can resume the normal lighting of the pixels except the defective pixel.

In view of the foregoing, it is desirable to provide an LED driving apparatus, a driving method thereof, and a readable storage medium, which enable real-time monitoring of data driving output signals of a previous stage and a next previous stage when one or more LEDs in an LED string are driven, and complete reconstruction of a serial communication link of the LED string at one time and simultaneously complete driving of LEDs of the string correctly when the previous stage driving apparatus is damaged.

Disclosure of Invention

An object of the present invention is to provide an LED driving device for driving one or more LEDs in a series of LEDs, the LED driving device being an nth stage LED driving device of a multi-stage LED driving device formed in series, N being greater than or equal to 2, the nth stage LED driving device comprising:

a reset module configured to output a reset signal when it is detected that an nth data driving signal output by the (N-1) th stage LED driving device has an input pulse width;

The signal counting module is configured to count the input (N-1) th-stage data driving signal when the reset signal is not received, and output a mark signal when the number of bits required by driving the (N-1) th-stage LED driving device is counted;

A signal selection module configured to select an inputted nth data driving signal as a data driving signal to be demodulated when the flag signal is not received, and to select an inputted (N-1) th data driving signal as a data driving signal to be demodulated when the flag signal is received; and

And the signal demodulation module is configured to demodulate the driving data of the bit number required by the N-th LED driving device from the data driving signal to be demodulated, and obtain the (N+1) -th data driving signal according to the data driving signal of the subsequent bit number.

In a possible embodiment, the nth stage LED driving apparatus further includes a signal delay module configured to delay the (N-1) -th stage data driving signal to be inputted to the signal counting module and the signal selecting module, respectively.

In one possible embodiment, the signal count module is further configured to reset the count to zero and the flag signal to reset in response to the reset signal.

In one possible embodiment, the reset module is further configured to: when the N-stage LED driving device is powered on or initialized, a reset signal is output; and outputting a reset signal when the nth stage LED driving device completes signal demodulation.

In one possible embodiment, the nth stage LED driving apparatus further includes a memory configured to store the driving data demodulated by the signal demodulation module.

The second aspect of the present invention provides an LED driving device comprising a plurality of LED driving devices formed in series, wherein the nth stage LED driving device is the LED driving device according to any one of the above embodiments, N being equal to or greater than 2; the 1 st stage LED driving device comprises a signal demodulation module which is configured to demodulate driving data of bits required by the 1 st stage LED driving device from data driving signals to be demodulated, and obtain a2 nd stage data driving signal according to the data driving signals of the subsequent bits.

A third aspect of the present invention provides an LED driving method for driving one or more LEDs in a series of LEDs driven by an N-th stage LED driving device in a multi-stage LED driving device formed in series, N.gtoreq.2, comprising:

outputting a reset signal by the reset module when it is detected that the nth data driving signal output by the (N-1) th stage LED driving device has an input pulse width;

When the reset signal is not received, the signal counting module counts the input (N-1) th-stage data driving signal, and when the number of bits required by driving the (N-1) th-stage LED driving device is counted, a mark signal is output;

When the sign signal is not received, the signal selection module selects the input N-th data driving signal as a data driving signal to be demodulated, and when the sign signal is received, the signal selection module selects the input (N-1) -th data driving signal as the data driving signal to be demodulated; and

The signal demodulation module demodulates the driving data of the bit number needed by the N-th LED driving device from the data driving signals to be demodulated, and obtains the (N+1) -th data driving signal according to the data driving signals of the subsequent bit number.

In one possible embodiment, the LED driving method further includes delaying the (N-1) -th data driving signal to be inputted to the signal counting module and the signal selecting module, respectively.

In one possible embodiment, the LED driving method further includes resetting the count to zero and resetting the flag signal in response to the reset signal.

A fourth aspect of the invention provides a computer readable storage medium storing a program, on which a computer program is stored which, when executed by a processor, carries out a method as any one of the possible embodiments of the method above.

The beneficial effects of the invention are as follows: when one or more LEDs in the LED lamp string are driven, the output signals of the front stage can be monitored in real time, when the front stage driving device is damaged, the reconstruction of the serial communication link of the LED lamp string is completed once, and meanwhile, the LED lamp group driven by the current stage is accurately lightened according to the LED pixel data driving signal flow sent by the lamp string main controller. In addition, the technical scheme of the invention is more reasonable and intelligent, and the reliability and convenience of the LED lamp string application project are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram showing a conventional driving connection manner of an LED string light;

FIG. 2 is a schematic diagram illustrating exemplary encodings and drive data processing involved in LED string drive control;

FIG. 3 is a schematic connection diagram of a serially formed multi-stage LED driver device according to an embodiment of the present application;

FIG. 4 is a schematic block diagram of internal circuit modules of an N-th stage LED driving device according to an embodiment of the present application in a multi-stage LED driving device formed in series, wherein N.gtoreq.2;

FIG. 5 is an exemplary workflow diagram of the Nth stage LED driver of FIG. 4, N+.2, according to an embodiment of the application; and

Fig. 6 is a schematic flowchart showing an LED driving method according to an embodiment of the present application.

Detailed Description

In order to make the technical scheme and advantages of the present application more apparent, embodiments of the present application will be described in further detail with reference to the accompanying drawings. Those skilled in the art will appreciate that the same or similar modules are denoted by the same reference numerals. The execution order of the steps is not limited in the present application, and for example, when the description method includes the step a and the step b, the step a and the step b may be sequentially performed, or the step b and the step a may be sequentially performed. In addition, the meaning of the application pertaining to include, contain, have etc. is open, i.e. when describing a component comprising, containing, or having a first, second, third module, it means that other modules may also be included in addition to the first, second, third module.

Fig. 2 is a schematic diagram showing exemplary encodings and drive data processing patterns involved in LED string drive control.

As a method for controlling driving of the LED string, a serial communication coding method and a driving data processing method shown in fig. 2 can be generally used. Specifically, a in fig. 2 exemplarily shows a single-line return-to-zero code. In the case of driving a plurality of unit pixels in a serial cascade of communication signals, the single-wire zero-return-code communication protocol may be generally employed in an LED string. The data is divided into a "0" code and a "1" code. The "0" code is composed of a high-level pulse width T0H and a low-level pulse width T0L, and the "1" code is composed of a high-level pulse width T1H and a low-level pulse width T1L. The control data of each LED is formed by combining the '0' code and the '1' code, and the specific high-level pulse width T0H and the low-level pulse width T0L of the two codes can be adjusted in different driving device implementations according to the specific specifications of the LED light string. Those skilled in the art will appreciate that this is merely exemplary and is not intended to limit the invention, as other possible serial encoding schemes are possible in practice.

As further shown in fig. 2B, for each driving device in the LED string driven in series, after latching the number of bits in the LED string driving data stream required for satisfying the LED to be driven by itself, the LED string driving data stream is forwarded to the next driving device through its output signal terminal DO, and so on. For example, B in fig. 2 illustrates a case where each driving device drives 3 LEDs. Wherein each LED in this example requires 8-bit data driving, there are n driving devices connected in series in the LED string, so that in each frame of data, the data driving signal D1 received by the first driving device is a data stream including all 3×8×n bits of data, and the number of required data driving signals corresponding to the 3 LEDs driven by the first driving device is 3×8=24 bits, so that the first driving device concatenates the subsequent data of 24 bits in the 3×8×n bits of data as the data driving signal D2 input to the second driving device, and so on.

For the single-wire return-to-zero code and serial communication data driving signal transmission mode involved in the driving control of the LED lamp string, if the data driving signals D1, D2 and … … Dn are simply cascaded, the situation that the current frame data stream cannot be rebuilt in time necessarily exists when a dead pixel exists.

Therefore, referring to fig. 3 to 6, a technical scheme in a driving data processing manner of an LED string light according to an embodiment of the present application is provided.

FIG. 3 is a schematic connection diagram of a serially formed multi-stage LED driver device according to an embodiment of the present application; FIG. 4 is a schematic block diagram of internal circuit modules of an N-th stage LED driving device according to an embodiment of the present application in a multi-stage LED driving device formed in series, where N is not less than 2 and N is a positive integer.

As shown in FIG. 3, a schematic connection diagram of a multi-stage LED driving device with a total of n is shown by taking control of 3 LEDs per LED driving device as an example, wherein n is equal to or greater than 2, and n is a positive integer. As shown, each LED driver U1, U2, … … Un (n.gtoreq.2, n is a positive integer) of the multi-stage LED driver formed in series includes a signal input DIN, a standby signal input DINA, and LED driver ends L1, L2, and L3. When a plurality of LED driving devices are connected in series to form a multi-stage LED driving device, the signal input terminal DIN of each LED driving device of 2 nd or more stages in the multi-stage LED driving device receives the output signal of the previous stage LED driving device, i.e., is connected with the data driving signal output terminal DO of the previous stage LED driving device. The standby signal input terminal DINA of each LED driving device above the 2 nd stage receives the data driving signal of the LED driving device of the previous stage, and the signal is used as the auxiliary output driving signal of the current stage for reconstructing the auxiliary data driving signal, i.e. the standby signal input terminal DINA is connected with the data driving signal output terminal DO of the LED driving device of the previous stage. According to the embodiment of the present application, the data driving signals controlling all LEDs in the LED string may be output by the external main controller, that is, the data driving signal data stream including the driving data controlling all LEDs in the LED string may be transmitted to the 1 st stage LED driving device U1 in the multi-stage LED devices formed in series in a serial communication manner by the external main controller. The main controller may typically be a central processing unit CPU or a microcontroller MCU. Accordingly, it will be understood by those skilled in the art that the data driving signal of the previous stage LED driving device received by the standby signal input DINA of the 2 nd stage LED driving device U2 is also from the main controller.

In accordance with an embodiment of the present application, and in conjunction with the description of FIG. 2, those skilled in the art will appreciate that a single LED may generally be PWM controlled. For example, when a single LED adopts 8-bit PWM control, the total number of data bits of the data driving signal required for each frame of the LED driven by each of the LED driving devices U1, U2, … … Un connected in series according to the embodiment of the present application is 8×3=24 bits, and when a single LED adopts 16-bit PWM control, the total number of data bits of the data driving signal required for each frame of the LED driven by each of the LED driving devices U1, U2, … … Un according to the embodiment of the present application is 16×3=48 bits. Those skilled in the art will appreciate that although a single LED driving device is shown in fig. 3 to drive three LEDs, this is not intended to limit the present application. A single LED driving device according to an embodiment of the present application may also drive other numbers of LEDs, such as m (m is a positive integer different from 3). When the single LED adopts 8-bit PWM control, the total number of bits of data driving signals required for each frame of the LED driven by each of the LED driving devices U1, U2, … … Un connected in series in the embodiment according to the present application is 8×m bits. Of course, accordingly, the total driving data input from the external main controller is 8×m×n bits. When a single LED is controlled by using 16-bit PWM, the total number of bits of data of the data driving signal required for each frame of the LED driven by each of the LED driving devices U1, U2, … … Un according to the embodiment of the present application is 16×m bits, and at this time, the total driving data input from the external main controller is 16×m×n bits accordingly.

By the above connection, the LED driving terminals L1, L2, L3 of each LED driving device output PWM data driving signals corresponding to each cycle of each LED to control on and off of each LED according to the driving data driving of the above form.

It should be noted that, as shown in fig. 3, each stage of LED driving device U1, U2 … … Un (n is not less than 2, n is a positive integer) in the multi-stage LED driving device is a single LED driving device according to an embodiment of the present application, and when used in series, the standby signal input terminal DINA in the 1 st stage of LED driving device U1 is empty. According to the embodiment of the present application, when the multi-stage LED driving device according to the present application is formed in series, the 1 st stage LED driving device is not limited to the single LED driving device according to the embodiment of the present application, that is, the 1 st stage LED driving device in the multi-stage LED driving device according to the embodiment of the present application may be another type of LED driving device as long as the LED driving device has the driving data of the number of bits required for demodulating the 1 st stage LED driving device from the data driving signal to be demodulated from the data driving signal outputted from the main controller, and obtains the data driving signal of the 2 nd stage LED driving device according to the data driving signal of the subsequent number of bits. Specific reasons will be described below in connection with the structure and function of the LED driving device of the present application. The structure and functional implementation of the nth stage LED driving apparatus according to the embodiment of the present application in the multistage LED driving apparatus formed in series, (n.gtoreq.2) will be described below with reference to an exemplary internal circuit block diagram shown in fig. 4. It will be appreciated by those skilled in the art that although N.gtoreq.2 is shown herein for clarity of description, the LED driver 40 according to embodiments of the present application may be used as a level 1 driver as long as the standby signal input DINA is left empty as shown in FIG. 3. Further, for convenience of description, it is assumed hereinafter that each LED driving device 40 controls 3 LEDs, and a single LED is controlled using an 8-bit PWM signal.

As shown in fig. 4, the LED driving apparatus 40 according to an embodiment of the present application may include a reset module 401, a signal counting module 403, and a signal selecting module 405.

In the figure, DIN represents the data driving signal of the LED driving device of the current stage, DINA represents the data driving signal input to the LED driving device of the previous stage, and DO1 represents the data driving signal to be demodulated. In other words, when the previous stage LED driving device 40 represents the nth stage LED driving device among the multi-stage LED driving devices formed in series, the previous stage LED driving device represents the N-1 th stage LED driving device, and the next stage LED driving device represents the n+1th stage LED driving device. As shown in fig. 4, the LED driving apparatus 40 according to the embodiment of the present application uses the signal selection module 405 to selectively perform the data driving signal to be demodulated according to the flag signal SW output from the signal counting module 403.

In particular, it will be understood by those skilled in the art that when the driving device of the LED fails, the data driving signal output DO will not have a normal digital signal output, and the stage of LED will not be normally lighted, i.e., once the LED driving device fails, the data driving signal output DO will not have a signal output of which the high level and the low level are changed. Therefore, according to the embodiment of the present application, the reset module 401 monitors the previous stage LED driving device, when detecting that the data driving signal DIN is a signal with a high-low level change, the signal selecting module 405 selects the current stage data driving signal DIN as the demodulated data driving signal DO1, and once detecting that the data driving signal DIN of the current stage LED driving device 40 is not a signal with a high-low level change, the signal selecting module 405 selects the previous stage data driving signal DINA as the data driving signal DO1 to be demodulated, so that when the driving device of the previous stage LED has a dead spot, the serially connected multi-stage LED device can still smoothly complete the subsequent processing action, that is, complete the reconstruction of the driving data in real time, thereby ensuring that the LED strings driven by the current stage and the subsequent stage can still be normally driven.

Further specifically, since the data driving signal of the previous stage is 8×3=24 bits more data than the data driving signal input to the current LED driving device, in the present application, the data composition of the previous stage data driving signal DINA is determined by the count of the signal counting module 403 and the determined data composition is notified to the signal selecting module 405 by the output flag signal SW, and the timing of starting the count of the signal counting module 403 is controlled by the reset module 401. According to an embodiment of the present application, the signal counting module 403 starts counting once the reset module 401 detects that the previous stage LED driving device has failed. Preferably, the signal counting module 403 outputs the flag signal SW, which has determined the data of the previous stage data driving signal DINA that is independent of the data driving signal of the number of bits required to drive the present stage LED, to the signal selecting module 405 when counting the same number of bits as the number of bits required to drive the previous stage LED since the start of the counting. Specifically, in this example, the signal counting module 403 outputs a flag signal SW indicating that the previous stage data driving signal DINA has a data driving signal having a number of bits sufficient to drive the present stage LED to the signal selecting module 405 when the first 24 bits of data are counted from the start of counting, i.e., after 24 bits are counted.

Accordingly, it should be understood by those skilled in the art that the signal counting module 403 is always attempting to count, but outputs a reset signal whenever the signal input terminal DIN has data, the reset module 401 monitoring the previous stage LED driving device, because the signal counting module 403 stops the counting process, and the condition of outputting the flag signal SW cannot be satisfied, at this time, the data driving signal DIN of the current stage is selected as the demodulated data driving signal DO1 by the signal selecting module 405. Through the above process, when the signal input terminal DIN has the current stage data driving signal accessed, the current stage data driving signal DIN is selected as the demodulated data driving signal DO1, and when the data driving signal DIN of the current stage LED driving device 40 is detected to be not a signal with high-low level change, the previous stage data driving signal DINA is selected as the data driving signal DO1 to be demodulated, so that when the driving device of the previous stage LED has bad pixels, the serially connected multi-stage LED devices can still smoothly complete the subsequent processing actions, namely, the reconstruction of driving data is completed in real time, and the LED strings driven by the current stage and the subsequent stages can still be normally driven.

Preferably, the signal counting module 403 may count the transition edges. It will be appreciated by those skilled in the art that the flag signal SW may be designed to be high level "1", or the flag signal SW may be designed to be low level "0". When the signal selection module 405 receives the flag signal SW, the data driving signal to be demodulated is switched to the previous stage data driving signal DINA, and thus the flag signal SW acts as an enable signal for signal switching.

Accordingly, control of the start of counting by the signal counting module 403 may be implemented by the reset module 401. The reset module 401 may generate the reset signal RST to reset the signal count module 403 when it detects that the data driving signal DIN of the LED driving device of the current stage has a PWM-shaped signal output, that is, when it detects a high level pulse width. Specifically, when the reset signal RST is generated, the count in the signal count block 403 is reset to zero, and at the same time, the flag signal SW is also reset.

According to the embodiment of the application, the timing of starting counting is determined by the reset module 401, and the flag signal SW is used as a control signal for determining the flag formed by the signals in the previous stage of data driving signals and the signal selection module 405 starts to act, so that by adopting the technical scheme of the application, as long as the previous stage of LED driving device has dead pixels, the LED driving device switches the data driving signal of the previous stage of LED driving device into the data driving signal to be demodulated at the current stage, thereby completing the real-time monitoring and reconstruction of the input data driving signal.

The LED driving device according to an embodiment of the present application may further include a delay module 407. The delay module 407 delays the previous stage data driving signal DINA to be input to the signal counting module 403 and the signal selecting module 405, and the delay time ensures that the signal reconstruction circuit according to the present application can be implemented correctly. Preferably, the delay time is less than the width of the "0" code high pulse width T0H defined by the LED serial communication. In order to distinguish the delayed previous stage data driving signal DINA, the delayed previous stage data driving signal is denoted as DINA' in fig. 4 and the following.

According to an embodiment of the present application, the LED driving apparatus may further include a signal demodulation module 409. The signal demodulation module 409 may process the data driving signal DO1 to be demodulated, which is selected by the signal selection module 405, into the signal demodulation module 409. Preferably, the data stream of the data driving signal DIN is gated into the signal demodulation module 409 by default for processing after the device is powered on and reset, and once the signal counting module 403 sends the flag signal SW, the signal selection module 405 gates the data stream of the previous stage data driving signal into the signal demodulation module 409 for processing. It will be appreciated by those skilled in the art that after the previous stage data driving signal DINA is delayed by the signal delay module 407, the signal selection module 405 gates the data stream of the delayed previous stage data driving signal DINA' into the signal demodulation module 409 for processing. Specifically, the signal demodulation module 409 may demodulate the number of bits required for the LED to be driven by itself from the data driving signal DO1 to be demodulated output from the signal selection module 405, and shape and amplify the subsequent signal, and then output the resultant signal from the data driving signal output terminal DO, where the output signal may be used as the data driving signal DIN of the next stage LED driving device and the previous stage data driving signal DINA of the next stage LED driving device.

According to an embodiment of the present application, the reset module 401 may further detect a power-on reset signal POR and a demodulation completion signal DR, and output a reset signal RST based on the power-on reset signal POR indicating power-on or initialization when the LED driving apparatus is powered on or initialized; when the demodulation of the signal demodulation module 409 of the LED driving device is completed, a reset signal RST is output based on the demodulation completion signal DR indicating that the demodulation is completed, and when the device monitors that the previous stage LED driving device has a "dead pixel", the signal demodulation module 409 also indicates that the LED driving device completes the signal reconstruction.

Preferably, the LED driving apparatus according to an embodiment of the present application may further include a latch (not shown in fig. 4) through which data of a driving bit number required for the demodulated current stage LED driving apparatus may be stored, and further, the latched data driving signal may be provided to each LED under the control of the clock signal, thereby turning on and off the corresponding LED according to the control of the main controller.

Through the structural configuration of the LED driving device, when the driving device of the previous stage LED has dead pixels through a simple circuit structure and a logic process, the serially connected multi-stage LED device can smoothly finish subsequent processing actions, namely, reconstruction of driving data is finished in real time, so that the LED strings driven by the current stage and the subsequent stage can still be normally driven.

With further reference to fig. 5, an exemplary workflow diagram of the actions of the various modules in the LED driving apparatus according to an embodiment of the application is shown.

As shown in fig. 5, counting the delayed previous stage data driving signal is shown here as long as the reset signal of the reset module 401 does not output the reset signal RST, i.e., counting the previous stage data driving signal, it should be understood by those skilled in the art that this is not intended to limit the present invention. In this step, the number of driving bits required for the previous stage driving can be counted from zero. The reset module can receive the data driving signal, and when the data driving signal has an input pulse width, the reset module outputs a reset signal; or the reset module may also output a reset signal upon determining that the power-on reset signal POR or the demodulation completion signal DR of the signal demodulation module is received. Preferably, the demodulation completion signal DR may be output after the completion of the data transfer of the subsequent data is determined, and it will be understood by those skilled in the art that this is not limitative, but that the demodulation completion may be determined by other means and the demodulation completion signal DR may be issued.

When the number of driving bits required for the previous stage driving is counted, the data driving signal to be demodulated is switched from the data driving signal of the current stage to the previous stage data driving signal, and the delayed previous stage data driving signal is shown to be gated into the signal demodulation module 409 for subsequent processing; when the count value does not satisfy the number of bits required for the own LED driving number, the current stage data driving signal DIN is gated into the signal demodulation module 409 to be processed.

The signal demodulation module 409 demodulates data required for driving the previous stage LED from the data driving signal to be demodulated, and shapes and amplifies the data of the subsequent number of bits in the data driving signal to output.

It will be appreciated by those skilled in the art that each of the reset module 401, the signal count module 403, the signal select module 405, the delay module 407, and the signal demodulation module 409 according to the present application may be implemented by a limited number of series-parallel combinations of switches, flip-flops, and comparator circuits.

It will also be appreciated by those skilled in the art that although the LED driving apparatus 40 is shown in fig. 3 as a single package and the multi-stage LED driving apparatus is shown as a form in which a plurality of LED driving apparatuses 40 individually packaged are connected in series, the multi-stage LED driving apparatus according to the present application is not limited thereto, and the multi-stage LED driving apparatus may also take the form of one chip or firmware, and the series connection of the plurality of LED driving apparatuses 40 or the series connection of the 1 st stage LED driving apparatus having only demodulation of the total data driving signal and the plurality of LED driving apparatuses 40 may be embodied in the individually packaged multi-stage LED driving apparatus in the form of internal connection.

Referring to FIG. 6, there is also provided an LED driving method for driving one or more LEDs in a series of LEDs driven by an N-th stage LED driving device of a multi-stage LED driving device formed in series, N.gtoreq.2, according to an embodiment of the present application.

Step S601, a reset step. Alternatively, when it is detected that the nth data driving signal outputted by the (N-1) th stage LED driving device has an input pulse width, a reset signal is outputted by the reset module.

Step S603, counting step. Alternatively, when the reset signal is not received, the signal counting module counts the input (N-1) -th stage data driving signal, and when the number of bits required for driving the (N-1) -th stage LED driving device is counted, a flag signal is output.

Step S605, a signal selection step. Alternatively, when the flag signal is not received, the signal selecting module selects the inputted nth data driving signal as the data driving signal to be demodulated, and when the flag signal is received, the signal selecting module selects the inputted (N-1) th data driving signal as the data driving signal to be demodulated.

Step S607, demodulates the data driving signal to be demodulated. Specifically, the signal demodulation module may demodulate the driving data of the number of bits required by the nth stage LED driving device from the data driving signal to be demodulated, and obtain the (n+1) th stage data driving signal according to the data driving signal of the subsequent number of bits.

By the method, when one or more LEDs in the LED light string are driven, the output signal of the previous stage can be monitored in real time, and when the previous stage driving device is damaged, the reconstruction of the serial communication link of the LED light string is completed in real time once, and meanwhile, the driving of the LEDs of the light string is completed correctly.

According to an embodiment of the present application, the LED driving method may further include delaying the (N-1) -th data driving signal to be inputted to the signal counting module and the signal selecting module, respectively.

According to an embodiment of the present application, the LED driving method further includes resetting the count to zero and resetting the flag signal in response to the reset signal.

It will also be appreciated by those skilled in the art that the LED driving device of the present application may also be embodied in the form of a computer-readable storage medium having stored thereon a program which, when executed by a computer, performs the above-described method steps.

In particular, according to the present embodiment, the above-described process may be implemented as a computer software program or a hardware program expressed in a hardware description language. For example, the present embodiments include a computer program product comprising a computer program tangibly embodied on a computer-readable medium, the computer program comprising program code for performing the method described above. In such embodiments, the computer program may be downloaded and installed from a network via a communication portion, and/or installed from a removable medium.

The flowcharts and diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to the present embodiments. In this regard, each block in the flowchart or schematic diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the diagrams and/or flowchart illustration, and combinations of blocks in the diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

It should be understood that the foregoing examples of the present invention are provided merely for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention, and that various other changes and modifications may be made therein by one skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. An LED driving device for driving one or more LEDs in a series of LEDs, wherein the LED driving device is an nth stage LED driving device in a multi-stage LED driving device formed in series, N being greater than or equal to 2, the nth stage LED driving device comprising:

a signal counting module configured to count the input (N-1) -th stage data driving signal when the reset signal is not received, and to output a flag signal when the number of bits required for driving the (N-1) -th stage LED driving device is counted;

A signal selection module configured to select an input nth data driving signal as a data driving signal to be demodulated when the flag signal is not received, and to select an input (N-1) th data driving signal as a data driving signal to be demodulated when the flag signal is received;

The signal demodulation module is configured to demodulate driving data of bits required by the N-th LED driving device from data driving signals to be demodulated, and obtain an (N+1) -th data driving signal according to the data driving signals of the subsequent bits; and

And the latch is configured to store the demodulated data of the driving bit number required by the Nth-stage LED driving device.

2. The LED driving apparatus according to claim 1, wherein the nth stage LED driving apparatus further includes a signal delay module configured to delay the (N-1) -th stage data driving signal to be inputted to the signal counting module and the signal selecting module, respectively.

3. The LED driving device of claim 1, wherein the signal count module is further configured to reset the count to zero and the flag signal to reset in response to the reset signal.

4. The LED driving device of claim 1, wherein the reset module is further configured to:

Outputting the reset signal when the nth stage LED driving device is powered on or initialized; and

And outputting the reset signal when the Nth-stage LED driving device completes signal demodulation.

5. The LED driving apparatus according to claim 2, wherein the nth stage LED driving apparatus further comprises a memory configured to store the driving data demodulated by the signal demodulation module.

6. An LED driving device is characterized by comprising a plurality of stages of LED driving devices formed in series,

Wherein the N-th LED driving device is the LED driving device according to any one of claims 1 to 5, and N is more than or equal to 2; the 1 st-stage LED driving device comprises a signal demodulation module, is configured to demodulate driving data of bits required by the 1 st-stage LED driving device from data driving signals to be demodulated, and obtains a2 nd-stage data driving signal according to the data driving signals of the subsequent bits.

7. An LED driving method for driving one or more LEDs in a series of LEDs driven by an nth stage LED driving device of a multi-stage LED driving device formed in series, N being 2 or more, comprising:

When the reset signal is not received, the signal counting module counts the input (N-1) stage data driving signal, and after counting the number of bits required by the (N-1) stage LED driving device for driving, a sign signal is output;

And demodulating the driving data of the bit number required by the N-th LED driving device from the data driving signal to be demodulated by the signal demodulation module, and obtaining an (N+1) -th data driving signal according to the data driving signal of the subsequent bit number.

8. The LED driving method of claim 7, further comprising delaying the (N-1) -th data driving signal to be inputted to the signal counting module and the signal selecting module, respectively.

9. The LED driving method of claim 7, further comprising resetting a count to zero and resetting the flag signal in response to the reset signal.

10. A computer readable storage medium storing a program, on which a computer program is stored, which computer program, when being executed by a processor, implements the method according to any of claims 7-9.