CN112071260A

CN112071260A - Micro LED light-emitting drive circuit and drive method

Info

Publication number: CN112071260A
Application number: CN202010998783.2A
Authority: CN
Inventors: 陈廷仰; 廖志洋
Original assignee: Yuchuang Semiconductor Shenzhen Co ltd
Current assignee: Yuchuang Semiconductor Shenzhen Co ltd
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2020-12-11

Abstract

The invention discloses a light-emitting driving circuit and a driving method of a micro LED, and relates to the technical field of light-emitting driving circuits and driving methods. The micro LED driving circuit comprises a micro LED light-emitting driving circuit and a starting time, wherein the light-emitting driving circuit part comprises a plurality of Shift registers (SFR), Level Shifters (LS) and Buffers (BUF), the output of the SFR is connected with the LS, the output of the LS is connected with the BUF, and the output of the BUF is connected with a micro LED pixel part. The invention reduces the error of pixel data by setting the light-emitting drive circuit to replace the on-time control with the off-time control, so that the micro LED has small electric leakage in the light-emitting period.

Description

Micro LED light-emitting drive circuit and drive method

Technical Field

The invention belongs to the technical field of a light-emitting drive circuit and a drive method, and particularly relates to a light-emitting drive circuit and a drive method of a micro LED.

Background

The micro LED is much better than the OLED in terms of color richness and viewing fatigue, and the conventional light emitting driving circuit of the OLED uses a shift register to shift the non-light emitting time one by one, so that the shift register is turned off when the scan line is turned on to avoid the unexpected flickering during the data line writing, or the turning off time is adjusted to achieve the brightness adjustment effect. However, the micro LEDs with small spacing often have a problem of insufficient storage capacitor C and large leakage current, the conventional light emitting driving circuit uses off-time control to make the micro LEDs emit light in a time interval with large leakage current, the brightness of the micro LEDs is too high, the light emitting time is generally used below 30%, if the light emitting driving circuit uses off-time control, the off-time needs to extend to 70% of the time of the previous frame, and this structure can make the driving light emitting driving circuit need additional control time of the previous frame.

Disclosure of Invention

The invention aims to provide a light-emitting driving circuit and a driving method of a micro LED, which aim to solve the existing problems: the micro LED with small spacing often has the problem of insufficient storage capacitor C and large leakage current, the traditional light-emitting drive circuit can make the micro LED emit light in a time interval with large leakage current by using closing time control, the brightness of the micro LED is too high, the light-emitting time is generally used below 30 percent, if the light-emitting drive circuit is controlled by closing time, the closing time of the light-emitting drive circuit needs to extend to 70 percent of the time of a previous frame, and the framework can make the light-emitting drive circuit need to have extra control time of the previous frame.

In order to solve the technical problems, the invention is realized by the following technical scheme:

the invention relates to a micro LED light-emitting drive circuit and a drive method, which comprises a micro LED, an EM drive circuit and a turn-on time, wherein the EM drive circuit comprises a plurality of SFRs, LS and BUF, the output of the SFRs is connected with the LS, the output of the LS is connected with the BUF, and the output of the BUF is connected with the micro LED.

Further, the input end of the SFR is connected with STV and CLK, and the output end of the SFR is connected with STV of the lower-level SFR.

Further, the ON time width of the output EM of the LS accounts for more than 70% of the total ON-off time.

Further, each rising edge of the EM driving circuit is a falling edge of a driving waveform of SCAN.

Further, the ON time width of the EM driving circuit is the ON time of the shift register.

Further, the high level time of the start signal of the EM driving circuit occupies six cycles of the clock signal.

Further, the high level time of the start signal of the EM driving circuit is the same as the high level time of the EM.

Further, a high level time of a start signal of the EM driving circuit and a high level time of an initial EM differ by one period of a clock signal in a waveform diagram.

Furthermore, the time width of the starting signal of the BUF can control the light emitting time of the micro LED pixel.

Further, the starting time is BUF to translate the light emitting time one by one.

The invention has the following beneficial effects:

1. the invention replaces the on-time control with the off-time control by arranging the light-emitting driving circuit, so that the pixel data error is reduced in the interval with smaller electric leakage during the micro LED light-emitting period.

2. The invention directly controls the lighting time of the pixels by adjusting the width of the initial signal and controlling the lighting time of the micro LED pixels, thereby avoiding the need of driving a lighting driving circuit in the previous frame.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a diagram of an exemplary light emitting driving circuit according to the present invention;

FIG. 2 is a driving waveform diagram of SCAN and EM of the present invention;

FIG. 3 is a waveform diagram of the start signal (EM _ STV) and the clock signal (EM _ CLK) of the EM driving circuit of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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.

Referring to fig. 1-3, the invention relates to a light emitting driving circuit and a driving method of micro LEDs, comprising micro LEDs, an EM driving circuit and a turn-on time, wherein the EM driving circuit comprises a plurality of SFRs, LS and BUF, the output of the SFR is connected with the LS, the output of the LS is connected with the BUF, and the output of the BUF is connected with the micro LEDs.

The input end of the SFR is connected with STV and CLK, and the output end of the SFR is connected with STV of the lower SFR, so that the lower SFR can receive signals after the upper SFR receives the signals.

The ON time width of the output EM of the LS, EM accounts for more than 70% of the total ON-off time so as to be controlled by the opening time.

The respective rising edges of the EM drive circuits are at the falling edges of the drive waveforms of SCAN in order to display the trigger signals.

The ON time width of the EM driving circuit is the opening time of the BUF so as to control the opening time of the BUF.

The high level time of the start signal of the EM driving circuit occupies six periods of the clock signal so as to lengthen the control time of the micro LED.

The high level time of the start signal of the EM driving circuit is the same as the high level time of the EM in order to control the high level time of the EM.

The high level time of the start signal of the EM driving circuit and the high level time of the initial EM are different in waveform diagram by one period of the clock signal so that the EMs do not interfere with each other.

The time width of the starting signal of the BUF can control the light-emitting time of the micro LED pixel so as to control the light-emitting time of the micro LED pixel.

The starting time is used for translating the light emitting time of the BUF one by one, and the light emitting time of the BUF one by one translation can be controlled.

One specific application of this embodiment is: when the clock signal of the EM driving circuit is sent by a periodic signal, the initial signal of the EM driving circuit receives the signal, after the clock signal passes through six periods, the high level time of the initial signal of the EM driving circuit is finished, when the initial signal of the EM driving circuit is at a high level, the high level receiving signal of the next EM driving circuit is after the clock signal passes through one period, and then the circuit is similar, the output end of each stage of EM driving circuit transmits the signal to the input end of each stage of LS circuit, the output end of the LS circuit transmits the signal to the input end of the BUF, and the output end of the BUF transmits the signal to the micro LED.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A micro LED light-emitting drive circuit and a drive method thereof comprise a light-emitting drive circuit and a turn-on time, and are characterized in that: the light-emitting driving circuit comprises a plurality of SFRs, LS and BUFs, wherein the outputs of the SFRs are connected with the LS, the outputs of the LS are connected with the BUF, and the outputs of the BUF are connected with the pixel parts of the micro LEDs.

2. The light emitting driving circuit and driving method of micro LED as claimed in claim 1, wherein the input terminal of the SFR is connected with the start Signal (STV) and the clock signal (CLK), and the output terminal of the SFR is connected with the STV of the next SFR.

3. The circuit and method of claim 1, wherein the ON time width of the emission control signal (EM) of the BUF output is less than 70% of the total ON/OFF time.

4. The light-emitting driving circuit and the driving method of a micro LED according to claim 1, wherein each rising edge of the light-emitting control signal (EM) generated by the light-emitting driving circuit is a falling edge of a driving waveform of a SCAN line Signal (SCAN).

5. The circuit and method of claim 1, wherein the ON time of the emission control signal (EM) is the ON time of the shift register.

6. A light-emitting driving circuit and driving method of micro LED according to claim 1, wherein the high level time of the start Signal (STV) of the light-emitting driving circuit is an integer multiple of the clock signal period.

7. A light-emitting driving circuit and driving method of micro LED according to claim 1, wherein the high time of the start Signal (STV) of the light-emitting driving circuit is the same as the high time of the generated light-emitting control signal (EM).

8. The light-emitting driving circuit and the driving method of micro LED according to claim 1, wherein the high-level time of the start signal of the light-emitting driving circuit and the high-level time of the initial EM are different from each other by one period of the clock signal in the waveform diagram.

9. The light-emitting driving circuit and the driving method of micro LED as claimed in claim 1, wherein the time width of the light-emitting control signal (EM) is capable of controlling the light-emitting time of the micro LED pixel portion.

10. The light emitting driving circuit and the driving method of micro LED as claimed in claim 1, wherein the EM turn-on time is shifted by one.