CN214504951U

CN214504951U - LED driving chip

Info

Publication number: CN214504951U
Application number: CN202120936536.XU
Authority: CN
Inventors: 管畅
Original assignee: Xiamen Hanshuo Microelectronics Co ltd
Current assignee: Xiamen Hanshuo Microelectronics Co ltd
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2021-10-26
Anticipated expiration: 2031-04-30

Abstract

The application discloses LED driver chip, including the cluster conversion module of being connected with sending card or last driver chip, be used for converting the data package that sending card sent into parallel signal, with the control module of cluster conversion module connection, be used for according to the video data package after the format conversion send drive signal to LED lamp pearl array display video signal who is connected with LED driver chip. Because the data conversion, the video processing, the scanning control and the like are integrated on one chip, the problem that a large amount of time is consumed in the data transmission process between the data conversion and the data driving is solved, and the display efficiency of the LED is improved. Meanwhile, the problems that in the prior art, a control system is matched with various driving chips due to separation of the control system and the driving chips, wide compatibility of the control system is considered, and waste of additionally added functional modules is caused can be avoided.

Description

LED driving chip

Technical Field

The application relates to the technical field of LEDs, in particular to an LED driving chip.

Background

With the development of science and technology, people have more and more demands on the definition and color richness of a video display device, and a Light Emitting Diode (LED) gradually comes into the lives of people as a display device for improving the display richness by controlling the display mode of a semiconductor light emitting diode.

At present, an LED driving chip is connected to an external receiving card, and the external receiving card is connected to a sending card, where the receiving card is used to convert video data sent by the sending card into a data format required by the LED driving chip, and the LED driving chip drives an LED electric quantity connected to the LED driving chip according to the converted video data. Because the LED driving chip is externally connected to the receiving card, a large amount of time is consumed during data transmission between data conversion and data driving (i.e., during the process of sending data to the LED driving chip by the external receiving card), and the LED display efficiency is reduced. Meanwhile, the receiving card needs to be considered to be matched with various LED driving chips, a plurality of functional modules can be additionally added, and in actual use, the receiving card is only connected with the specific LED driving chip and the specific LED array, so that the waste of the plurality of functional modules of the receiving card can be caused, for example, the receiving card can maximally support 256x256 LED arrays, and the waste of the functions of the receiving card can be caused due to the fact that the LED arrays of various manufacturers have various sizes, and only 120x135 are available. Meanwhile, as the LED is developed towards small spacing, more driving chips and receiving cards are required to be placed on the PCB in unit area, so that the space is crowded, and the difficulty in arranging the PCB is increased.

Therefore, it is an urgent problem to be solved by those skilled in the art how to improve the display efficiency and resource utilization of LEDs and reduce the number of system components.

SUMMERY OF THE UTILITY MODEL

The purpose of the application is to provide an LED driving chip, which is used for improving the display efficiency and the resource utilization rate of an LED and reducing the number of system components.

In order to solve the above technical problem, the present application provides an LED driving chip, including:

the serial-parallel conversion module is connected with the sending card or the upper LED driving chip and is used for performing serial-parallel conversion on the video data packet sent by the sending card or the upper LED driving chip;

the control module is connected with the serial-parallel conversion module and used for sending a driving signal according to the video data packet after serial-parallel conversion so that the LED lamp bead array connected with the control module can display video data corresponding to the driving signal;

the serial-parallel conversion module and the control module are arranged on the same chip.

Preferably, the control module includes:

the scanning control module is connected with the serial-parallel conversion module and is used for carrying out PWM modulation on the video data packet after format conversion according to the process parameters representing the lightening of the LED lamp bead array to output constant current output signals;

the constant current source driving module is connected with the scanning control module and the LED lamp bead array and is used for sending current driving signals to the LED lamp bead array according to the constant current output signals;

the line scanning driving module is connected with the scanning control module and the LED lamp bead array and used for sending a line scanning driving signal representing the lighting mode of the LED lamp bead array to the LED lamp bead array according to the constant current output signal;

wherein the current driving signal and the line scanning driving signal are collectively referred to as the driving signal.

Preferably, when the LED driving chip is a plurality of LED driving chips, the LED driving chip further includes:

the addressing module is respectively connected with the serial-parallel conversion module and the scanning control module and is used for sending the video data packet with the converted format to the scanning control module when judging that the video data packet after serial-parallel conversion is matched with the current address of the LED driving chip;

and the parallel-serial conversion module is connected with the addressing module and is used for converting the video data packet after format conversion into the video data packet subjected to address recoding and sending the video data packet to the lower LED driving chip.

Preferably, the method further comprises the following steps:

and the gamma table module is connected with the serial-parallel conversion module and is used for converting video content data contained in the video data packet after format conversion into video gray data according to control data contained in the video data packet after format conversion.

Preferably, the method further comprises the following steps:

and the point-by-point correction module is connected with the gamma table module and is used for correcting the video gray data according to the control data.

Preferably, the method further comprises the following steps:

and the cache module is connected with the point-by-point correction module and is used for storing the video gray data after correction processing.

Preferably, the method further comprises the following steps:

the flash memory interface module is used for storing the control data in a flash memory;

and the power-on configuration module is respectively connected with the flash memory interface module and the serial-parallel conversion module and is used for sending the control data to the addressing module through the flash memory interface module under the condition of power-on again so as to facilitate the addressing module to update the control data or send the control data to the lower-level LED driving chip.

Preferably, the method further comprises the following steps:

the power supply control module is connected with the serial-parallel conversion module and is used for adjusting the working voltage of the LED driving chip;

the work indication module is used for judging whether the constant current source driving module works normally or not and adjusting the working voltage according to the acquired working state data of the constant current source driving module.

Preferably, the constant current source driving module further includes: and the current DAC is used for displaying higher gray scale in the LED lamp bead array.

The application provides an LED driver chip, including be connected or higher level LED driver chip's serial-parallel conversion module with the sending card, be used for carrying out the format conversion with the video data package, with the control module that serial-parallel conversion module is connected, be used for sending drive signal according to the video data package after the format conversion to LED lamp pearl array display that is connected with LED driver chip and the video data that drive signal corresponds, wherein, serial-parallel conversion module and control module set up on same chip. Because the data conversion is realized by the serial-parallel conversion module, the data drive is realized by the control module, and the serial-parallel conversion module and the control module are arranged on the same chip, the problem that a large amount of time is consumed in the data transmission process between the data conversion and the data drive is avoided, the display efficiency of the LED is improved, the resource waste is reduced due to the adaptation of the control and drive units, the system link is simplified, and the PCB layout difficulty is optimized.

Drawings

In order to more clearly illustrate the embodiments of the present application, the drawings needed for the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings can be obtained by those skilled in the art without inventive effort.

Fig. 1 is a structural diagram of an LED driving chip according to an embodiment of the present disclosure;

fig. 2 is a structural diagram of an LED driving chip and an LED lamp bead array provided in the embodiment of the present application;

fig. 3 is a schematic structural diagram of a plurality of LED driving chips on a target unit board according to an embodiment of the present disclosure; the reference numbers are as follows:

the system comprises a sending card 10, an LED driving chip 11, a serial-parallel conversion module 12, a control module 13, an LED lamp bead array 14, a scanning control module 21, a line scanning driving module 22, a constant current source driving module 23, a gamma table module 24, a point-by-point correction module 25, a cache module 26, an addressing module 30, a parallel-serial conversion module 31, a power-on configuration module 32, a flash memory interface module 33 and a power control module 34.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without any creative effort belong to the protection scope of the present application.

The core of the application is to provide an LED driving chip for improving the display efficiency of an LED.

In order that those skilled in the art will better understand the technical solutions of the present invention, the following technical solutions are clearly and completely described in conjunction with the accompanying drawings and the detailed description, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a structural diagram of an LED driving chip according to an embodiment of the present application. As shown in fig. 1, the LED driving chip 11 includes:

and the serial-to-parallel conversion module 12 is connected to the sending card 10 or the upper LED driving chip 11, and is configured to convert the video data packet sent by the sending card 10 or the upper LED driving chip 11 into a parallel signal.

And the control module 13 connected to the serial-to-parallel conversion module 12 is configured to send a driving signal according to the video data packet after format conversion, so that the LED lamp bead array 14 connected to the control module 13 displays video data corresponding to the driving signal.

The serial-to-parallel conversion module 12 and the control module 13 are disposed on the same chip.

In the embodiment of the present application, the video data packet includes control data and video content data, where the control data is used to send a driving signal to the LED driving chip 11 according to a mode preset by a user, so that the LED lamp bead array 14 displays the driving signal according to the preset mode when displaying the driving signal.

It should be noted that, when the sending card 10 sends a video data packet, a serial manner is usually adopted, so that the LED driving chip 11 specifically converts the serial video data packet into a parallel video data packet, and the LED lamp bead array 14 can display video content data according to control data contained in the video data packet.

In order to further improve the display efficiency of the LED driving chip, as a preferred embodiment, the sending card 10 sends the video data packet to the LED driving chip 11 in a high-speed serial manner, and then the LED driving chip 11 further includes a high-speed serial input interface.

Further, when there are a plurality of LED driving chips 11, the LED driving chips 11 further include a high-speed serial output interface.

When a plurality of LED driving chips 11 are present, the LED driving chips 11 may be connected in series or in parallel. It can be understood that, in the specific implementation, one LED screen is formed by arranging a plurality of LED bead arrays 14, so that the LED driving chips 11 may have a series connection relationship or a parallel connection relationship.

As shown in fig. 1, the control module 13 includes:

and the scanning control module 21 is connected with the serial-parallel conversion module 12 and is used for performing PWM (pulse width modulation) debugging on the video data packet after format conversion according to the process parameters representing the lighting of the LED lamp bead array 14 and outputting a constant current output signal.

And the constant current source driving module 23 is connected with the scanning control module 21 and the LED lamp bead array 14 and is used for sending a current driving signal to the LED lamp bead array 14 according to the constant current output signal.

And a line scanning driving module 22 connected to the scanning control module 21 and the LED lamp bead array 14, and configured to send a line scanning driving signal representing a lighting mode of the LED lamp bead array 14 to the LED lamp bead array 14 according to the constant current output signal.

The current driving signal and the line scanning driving signal are collectively referred to as a driving signal.

It should be noted that the format conversion specifically converts serial to parallel, the process parameters specifically include lighting time of the LED lamp bead array 14 or a single LED lamp bead and a magnitude of the current driving signal, and the specific lighting time and the current driving signal are in inverse proportion, for example, when the LED brightness is the same, if the current driving signal is increased, the lighting time needs to be decreased.

In addition, the line scanning driving signal specifically controls each line of the light beads in the LED light bead array 14 to be turned on or off according to the constant current output signal.

Fig. 2 is a structure diagram of an LED driver chip and an LED lamp bead array provided in an embodiment of the present application. As shown in fig. 2, the IOUT _ R0 interface, the G0 interface, the B0 interface, the R1 interface, the G1 interface, the B1 interface to the R39 interface, the G39 interface, and the B39 interface of the constant current source driving module 23 are respectively connected to anodes of LED lamp beads in a corresponding column in the LED lamp bead array 14, and the L0 interface, the L1 interface to the L43 interface, and the L44 interface of the row scanning driving module 22 are respectively connected to cathodes of LED lamp beads in a corresponding row in the LED lamp bead array 14.

The LED driving chip comprises a serial-parallel conversion module connected with a sending card or a superior LED driving chip, a control module connected with the serial-parallel conversion module, and a driving signal sending module used for sending a video data packet according to the video data packet after format conversion so as to display video data corresponding to the driving signal on an LED lamp bead array connected with the LED driving chip, wherein the serial-parallel conversion module and the control module are arranged on the same chip. Because the data conversion is realized by the serial-parallel conversion module, the data drive is realized by the control module, and the serial-parallel conversion module and the control module are arranged on the same chip, the problem that a large amount of time is consumed in the data transmission process between the data conversion and the data drive is avoided, the display efficiency of the LED is improved, the resource waste is reduced due to the adaptation of the control and drive units, the system link is simplified, and the PCB layout difficulty is optimized.

As shown in fig. 1, in addition to the above embodiment, in the case that there are a plurality of LED driving chips 11, the LED driving chip 11 further includes:

and the addressing module 30 is respectively connected to the serial-parallel conversion module 12 and the scanning control module 21, and is configured to send the video data packet with the converted format to the scanning control module 21 when it is determined that the video data packet with the converted serial-parallel format matches the scanning control module 21.

And the parallel-serial conversion module 31 is connected to the addressing module 30, and is configured to convert the format-converted video data packet into a video data packet subjected to address re-encoding, and send the video data packet to the lower-level LED driving chip 11.

Fig. 3 is a schematic structural diagram of a plurality of LED driving chips on a target unit board according to an embodiment of the present disclosure. As shown in FIG. 3, the power management system SMPS (the addressing module 30) on the target unit board is connected to the VDD _3P3 interface, VDD _ R interface, VDD _ G interface, and VDD _ B interface of each LED driver chip 11, the processing system SMPS is connected to the I2C _ SDA interface and I2C _ SCL interface of the first LED driver chip 11, the I2C _ SDA interface and I2C _ SCL interface of the first LED driver chip 11 are connected to the VDD _3P3 interface of the first LED driver chip 11 through resistors, the VDD _1P8 interface, VDD _3P3 interface, VDD _ R interface, VDD _ G interface, and VDD _ B interface of each LED driver chip 11 are grounded through capacitors, the SPI _ MODE interface of the first LED driver chip 11 is grounded, the SPI _ CSn interface, SPI _ DO interface, SPI _ CLK interface are connected to the flash memory as the flash memory interface module 33 for reading the data stored on the unit board through the flash memory module, The CHIP of the whole unit board is powered on, wherein the FIRST CHIP signal indicates that the current CHIP is the FIRST CHIP, the FIRST CHIP on the target unit board is connected with the power control and flash memory control module, the FIRST CHIP interface is connected with the working voltage, the IREF _ R interface, the IREF _ G interface and the IREF _ B interface of each LED driving CHIP 11 are grounded through resistors, the LIN _ RX _ CLK _ P/N interface, the LIN _ RX _ DATA _ P/N interface, the LIN _ TX _ CLK _ P/N interface and the LIN _ TX _ DATA _ P/N interface of the FIRST LED driving CHIP 11 are connected with the previous unit board or the transmitting card 10, the LOUT _ TX _ CLK _ P/N interface, the LOUT _ TX _ DATA _ P/N interface, the LOUT _ RX _ CLK _ P/N interface and the LOUT _ RX _ DATA _ P/N interface of the last LED driving CHIP 11 are connected with the next unit board, the OUT _ R [39:0] interface, the OUT _ G [39:0] interface, the OUT _ B [39:0] interface, the L [44:0] interface of each LED driving chip 11, the LED bead Array 14 (RGB LED Array in the figure) of 40 × 45, the GND _ ANA interface and the GND _ DIG interface are grounded, the VPK _ H interface, the VPK _ R interface, the VPK _ G interface and the VPK _ B interface are grounded through capacitors respectively for providing a line scan off voltage and a turn-off voltage for turning off a line scan constant current source, G and B constant current sources, the VREF25 interface is grounded through a voltage regulator tube, connected to a working voltage through a resistor, and grounded through a capacitor, the GND _ REF interface is grounded for providing a stable reference voltage for the chips to generate an accurate current, the HRD _ RST _ N interface of each LED driving chip 11 is connected to a Reset, the INIT _ DONE interface is connected to a working voltage after being connected to a resistor, and then a pull-up signal is required to be explained: after all the LED driving chips 11 are connected together, before the power supply (the above working voltage) of the power supply of the LED driving chips 11 is normal, all the LED driving chips 11 are pulled down, after the power supply is normal, all the LED driving chips 11 output high impedance, at this time, all the LED driving chips 11 are normally operated, that is, all the LED driving chips 11 output high impedance, so that the INIT _ DONE interface is pulled up by the working voltage, and after the first LED driving chip 11 on the target unit board detects that the signal is high, the configuration data is sent. The TRIM _ R interface, the TRIM _ G interface, and the TRIM _ B interface of each LED driving chip 11 are grounded through resistors, respectively, and are used to adjust current uniformity among the plurality of chips.

It should be noted that, when there are a plurality of LED driving chips 11, the video data packets sent by the sending card 10 are subjected to address coding, that is, the video data packets corresponding to each LED driving chip 11 are in one-to-one correspondence with each address coding, so that the addressing module 30 determines whether the format-converted video data packets are matched with the LED driving chips 11.

It can be understood that, under the condition that there are a plurality of LED driving chips 11, in order to reduce the workload of the sending card 10, usually, the sending card 10 will send the video data packet corresponding to the LED driving chips 11 connected in series to the LED driving chips 11 at one time, so that the display accuracy of each LED driving chip 11 driving the corresponding LED bead array 14 can be ensured through the addressing module 30.

As shown in fig. 1, on the basis of the above embodiment, the LED driving chip 11 further includes:

and the gamma table module 24 is connected to the serial-to-parallel conversion module 12 and is configured to convert video content data included in the format-converted video data packet into video grayscale data according to control data included in the format-converted video data packet.

The control data includes video gray scale data for controlling the gamma table module 24 to output a predetermined number of bits.

In order to ensure that the brightness of each LED bead in the LED bead array 14 is uniform, as a preferred embodiment, as shown in fig. 1, the LED driving chip 11 further includes:

and a point-by-point correction module 25 connected to the gamma table module 24 for performing correction processing on the video gray data according to the control data.

It can be understood that, when the gamma table module 24 is connected to the point-by-point correction module 25, the control data is used for controlling the gamma table module 24 to output video gray scale data according to a preset number of bits, and simultaneously, is also used for controlling the point-by-point correction module 25 to make the brightness of each LED lamp bead uniform according to a preset LED brightness.

Further, as shown in fig. 1, the LED driving chip 11 further includes: and the buffer module 26 is connected with the point-by-point correction module 25 and is used for storing the video gray scale data after the correction processing. It should be noted that, since the time for the scan control module 21 to output the constant current output signal in the PWM debugging process is long, the buffer module 26 can prevent the video grayscale data after the correction process from being overwritten.

The LED drive chip that this application embodiment provided, LED drive chip still include with the gamma table module of deserializing module connection, because the control data that the gamma table module can be based on turns into video gray data with video content data, consequently guaranteed that LED lamp pearl array can normally show video content data.

and a flash memory interface module 33 for storing the control data in the flash memory.

The power-on configuration module 32 is connected to the flash interface module 33 and the serial-to-parallel conversion module 12, respectively, and is configured to send the control data to the addressing module 30 through the flash interface module 33 in case of power-on again, so that the addressing module 30 updates the control data or sends the control data to the lower LED driving chip 11.

It can be understood that after the position of the LED lamp bead array 14 is fixed, the control data will remain unchanged until the position of the corresponding LED lamp bead array 14 changes, so that the control data is stored in the flash memory, and when the power is turned on again, the control data does not need to be obtained again from the sending card 10 and the data format conversion is performed, thereby further improving the display efficiency of the LED.

and the power supply control module 34 is connected with the serial-parallel conversion module 12 and is used for adjusting the working voltage of the LED driving chip 11.

The work instruction module included in the constant current source driving module 23 and connected to the power control module 34 is configured to determine whether the constant current source driving module 23 works normally, and adjust the working voltage according to the acquired working state data of the constant current source driving module 23.

It can be understood that, in the process that the work indication module continuously judges whether the constant current source driving module 23 works normally, the work voltage of the LED driving chip 11 can be adjusted through the power control module 34, so that the minimum work voltage can be used to reach the state that the constant current source driving module 23 works normally, and the power consumption of the LED driving chip 11 can be further reduced while the LED lamp bead array 14 can work normally.

The LED driving chip further comprises a power supply control module connected with the serial-parallel conversion module, and the power supply control module can adjust the working voltage of the LED driving chip, so that the optimal working voltage can be selected, and the power consumption of the LED driving chip is reduced.

On the basis of the above embodiment, the constant current source driving module 23 further includes: and a current Digital-to-Analog Converter (DAC) for increasing the current level when the brightness is controlled by the PWM to further display a higher level of gray scale in the LED lamp bead array 14.

It can be understood that current DAC can produce multistage electric current, and to same current drive signal promptly, current DAC can produce the electric current of multiple size, consequently can be further improvement LED lamp pearl array 14's definition and colour richness for the video that LED lamp pearl array 14 shows is laminated with former video more, has improved user's use and has experienced the sense.

The LED driving chip provided by the present application is described in detail above. The embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present application without departing from the principle of the present application, and such improvements and modifications also fall within the scope of the claims of the present application.

It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Claims

1. An LED driving chip, comprising:

2. The LED driving chip according to claim 1, wherein the control module comprises:

3. The LED driving chip according to claim 2, wherein when the LED driving chip is plural, the LED driving chip further comprises:

4. The LED driving chip according to claim 2 or 3, further comprising:

5. The LED driving chip according to claim 4, further comprising:

6. The LED driving chip according to claim 5, further comprising:

7. The LED driving chip according to claim 3, further comprising:

8. The LED driving chip according to claim 2, further comprising:

9. The LED driving chip according to claim 2, wherein the constant current source driving module further comprises: and the current DAC is used for displaying higher gray scale in the LED lamp bead array.