Light emitting diode driver and display device using the same

Abstract

The present application provides a light emitting diode driver and a display device using the same. The light emitting diode driver includes a driving module and a plurality of current control modules. The driving module includes a plurality of bias circuits and a plurality of resistive devices, wherein any two of the bias circuits are electrically coupled to each other through at least one of the resistive devices. The current control modules are respectively coupled to the bias circuits, and each of the current control modules includes a current control circuit and a slew-rate enhancement circuit. The current control circuit is configured to output a driving current. The slew-rate enhancement circuit is electrically coupled to the current control circuit to output a complementary current.

Description

Technical Field

[0001] This invention relates to a light-emitting diode (LED) driver and a display device using the LED driver, and more particularly to an LED driver having a fast transient response and a display device using the same. Background Technology

[0002] With the development of display technology in recent years, the requirements for color resolution of display devices that display full-color images using light-emitting diodes (hereinafter referred to as "LED display devices") are becoming increasingly stringent. In traditional LED display devices, light-emitting diodes that generate different colors of light are used to produce different colors in each pixel. The color of each pixel can be adjusted by adjusting the output current value applied to each light-emitting diode.

[0003] However, in traditional LED driving circuits, parasitic capacitance can cause the actual output current applied to the LED to be less than the preset current value. Therefore, LED displays typically do not perform as well as expected in terms of color accuracy. In other words, the color resolution of LED displays is limited by the transient response time of traditional driving circuits. Summary of the Invention

[0004] To address the aforementioned technical deficiencies, this invention provides a light-emitting diode (LED) driver and a display device using the LED driver. This LED driver has a faster transient response, allowing the color accuracy and color resolution of the display device to be improved without a significant increase in standby current or static power consumption.

[0005] In one embodiment of the present invention, a light-emitting diode (LED) driver is provided. The LED driver includes a driving module and multiple current control modules. The driving module includes multiple bias circuits and multiple resistive devices, wherein any two bias circuits are electrically coupled to each other through at least one resistive device. The multiple current control modules are respectively coupled to the bias circuits, and each current control module includes a current control circuit and a slew rate enhancement circuit. The current control circuit outputs a driving current. The slew rate enhancement circuit is electrically coupled to the current control circuit to output a complementary current.

[0006] In some embodiments, the current control circuit includes a plurality of transistors whose gates are commonly coupled to a slew rate enhancement circuit.

[0007] In some embodiments, the current control circuit includes at least one transistor, the slew rate enhancement circuit includes a slew rate enhancement transistor having a control gate, a first terminal, and a second terminal, and the gate of at least one transistor and the first terminal of the slew rate enhancement transistor are coupled together to a control node.

[0008] In some embodiments, the slew rate enhancement circuit further includes a voltage setting circuit coupled to the control gate of the slew rate enhancement transistor to apply a preset bias voltage to the control gate of the slew rate enhancement transistor.

[0009] In some embodiments, the voltage setting circuit includes a first transistor and a second transistor, the first source terminal of the first transistor is electrically coupled to the second drain terminal of the second transistor, and the first drain terminal of the first transistor and the control gate terminal of the slew rate enhancement transistor are jointly coupled to a current source.

[0010] In some embodiments, the second end of the slew rate enhancement transistor is coupled to a power supply.

[0011] In some embodiments, each bias circuit includes an output node, and each resistive device is connected between the two output nodes of any two bias circuits.

[0012] In some embodiments, the current control circuit includes at least one transistor, the gate of which is coupled to a control node. Each current control module includes a first switching element connected between the control node and the output node.

[0013] In some embodiments, the drive module further includes a reference voltage circuit electrically coupled to each bias circuit.

[0014] In some embodiments, a resistive device is connected in series between every two bias circuits to form a resistive bias network.

[0015] In some embodiments, the number of resistive devices is equal to or greater than the number of bias circuits.

[0016] In some embodiments, the ratio of the number of bias circuits to the number of current control modules is greater than 0.5.

[0017] In another embodiment of the present invention, a display device is provided. The display device includes a pixel array and the aforementioned light-emitting diode (LED) driver. The pixel array includes a plurality of pixels, and each pixel includes a plurality of LEDs for generating light beams of different colors to output a mixed light beam. A current control module is electrically connected to each LED to control the color of the mixed light beam emitted by each pixel.

[0018] In some embodiments, each pixel contains a red LED, a blue LED, and a green LED.

[0019] Therefore, in the LED driver and the display device using the LED driver provided in the embodiments of the present invention, by means of any two bias circuits being electrically coupled to each other through at least one resistive device, and the slew rate enhancement circuit being electrically coupled to the current control circuit to output complementary current, the LED driver has a fast transient response and can improve the color accuracy and color resolution of the display device including the LED driver.

[0020] The above and other aspects of the present invention will become apparent from the following description of the embodiments in conjunction with the figures and illustrations, although variations and modifications may be made therein without departing from the spirit and scope of the novel concept of the invention. Attached Figure Description

[0021] The embodiments described herein can be better understood by referring to the following description and accompanying drawings, wherein:

[0022] Figure 1 This is a functional block diagram of a light-emitting diode driver according to an embodiment of the present invention.

[0023] Figure 2 This is a circuit diagram of a light-emitting diode driver according to an embodiment of the present invention.

[0024] Figure 3 This is a partial circuit diagram of a current control module according to an embodiment of the present invention.

[0025] Figure 4 This is a waveform diagram of a driving signal according to an embodiment of the present invention.

[0026] Figure 5 This is a comparative example and a schematic diagram of the current waveform of an embodiment of the present invention.

[0027] Figure 6 This is a schematic diagram of a display device according to an embodiment of the present invention.

[0028] The reference numerals in the attached figures are explained as follows:

[0029] 1: LED driver

[0030] 10: Driver Module

[0031] 100: Reference voltage circuit

[0032] 101: Bias Circuit

[0033] 102: Resistive device

[0034] 11: Current control module

[0035] 110: Current control circuit

[0036] 111: Slew rate enhancement circuit

[0037] 2: Light Emitting Diode

[0038] 2B: Blue LED

[0039] 2R: Red LED

[0040] 2G: Green LED

[0041] M1: Display device Detailed Implementation

[0042] The present invention is specifically described in the following embodiments, which are for illustrative purposes only, as many modifications and variations will be apparent to those skilled in the art. Throughout all views, the same numbers in different figures represent the same elements. As used in this specification and the following claims, unless the context clearly specifies otherwise, "a" and "the" have the meaning of plural reference, and "in" has the meaning of "within" and "above". Titles or subtitles may be used herein for the reader's convenience without affecting the scope of the invention.

[0043] The terms used herein generally have their ordinary meanings in the art. In case of any dispute, this document (including any definitions given herein) shall prevail. The same thing may be expressed in more than one way. Alternative terms and synonyms may be used for any terms discussed herein, and whether such terms are elaborated or discussed herein is not specifically defined herein. Listing one or more synonyms does not exclude the use of other synonyms. Examples of embodiments used anywhere in this specification, including examples of any terms, are illustrative only and should not be used to limit the scope and meaning of the invention or any exemplary terms. Similarly, the invention is not limited to the various embodiments given herein. Numbering terms such as “first,” “second,” or “third” may be used to describe various elements, signals, etc., and these numbers are only for distinguishing different elements or signals and should not be construed as imposing any substantial limitation on the elements, signals, etc.

[0044] refer to Figure 1This figure is a functional block diagram of a light-emitting diode (LED) driver according to an embodiment of the present invention. The LED driver 1 provided in this embodiment can be implemented in a display device, such as an LED display device. Therefore, multiple LEDs 2 can each generate light beams of different colors and together form one of the pixels in the display device. For example, LEDs 2 may include a red LED 2R, a blue LED 2B, and a green LED 2G, but the present invention is not limited thereto. The colored light beams generated by the LEDs 2 can be mixed to form a mixed light beam.

[0045] Specifically, the LED driver 1 includes a driving module 10 and multiple current control modules 11. In this embodiment, the driving module 10 includes a reference voltage circuit 100, multiple bias circuits 101, and multiple resistive devices 102.

[0046] refer to Figure 2 This figure, according to an embodiment of the present invention, is a circuit diagram of a light-emitting diode driver. A reference voltage circuit 100 is used to generate a reference voltage and is electrically connected to a bias circuit 101. In one embodiment, the reference voltage circuit 100 may include a comparator circuit 1001 and a transistor element 1002. The comparator circuit 1001 may include a comparator or an operational amplifier. Figure 2 As shown, the output terminal of the comparator circuit 1001 is electrically connected to the gate terminal of the transistor element 1002.

[0047] Furthermore, in this embodiment, the input terminal of the bias circuit 101 and the output terminal of the reference voltage circuit 100 are both connected to the reference node NR. For example... Figure 2 As shown, in this embodiment, each bias circuit 101 includes two transistors 101A and 101B. Furthermore, the gate terminal of transistor 101A serves as the input terminal of each bias circuit 101 and is electrically coupled to a reference node NR. The gate terminal and drain terminal of the other transistor 101B have the same potential, and the gate terminal of transistor 101B serves as the output node NA of each bias circuit 101. However, the invention is not limited to the embodiment provided herein. Each bias circuit 101 is electrically connected to one of the current control modules to supply bias current.

[0048] As shown in the figure Figure 1 and Figure 2As shown, the resistive device 102 is connected in series with the bias circuit 101 to form a resistive bias network. Specifically, any two bias circuits 101 are electrically coupled to each other through at least one resistive device 102, but the invention is not limited thereto. In another embodiment, two or more resistive devices 102 are connected in series between each pair of bias circuits 101. Therefore, the number of resistive devices 102 is equal to or greater than the number of bias circuits 101.

[0049] like Figure 2 As shown, each resistive device 102 is connected between the two output nodes NA of any two bias circuits 101. By connecting at least one resistive device 102 in series between any two bias circuits 101, the bias current output by one bias circuit 101 can be used to compensate the bias current output by the other bias circuit 101. The resistive device 102 may comprise a resistor, a transistor, a diode, or any combination thereof. Figure 2 In the embodiments described, each resistive device 102 is a resistor, but the present invention is not limited thereto. The operation and function of the bias circuit 101 and the resistive devices 102 will be described in detail below, and therefore will not be repeated here.

[0050] Please refer to Figure 1 The current control module 11 is electrically connected to the light-emitting diode 2, thereby driving the light-emitting diode 2 to emit light. Furthermore, the current control module 11 is electrically connected to the bias circuit 101. More specifically, each bias circuit 101 outputs a bias current to the corresponding current control module 11, thereby controlling the driving current output by the corresponding current control module 11 and the brightness of the corresponding light-emitting diode 2.

[0051] In this embodiment, the number of current control modules 11 is equal to the number of light-emitting diodes 2. Furthermore, in this invention, by increasing the number of bias circuits 101, the transient response speed of the light-emitting diode driver 1 can be improved. Thus, when multiple light-emitting diodes 2 need to be turned on simultaneously to generate a mixed beam, the bias circuits 101 can output bias currents separately, thereby allowing the current control modules 11 electrically connected to them to simultaneously control the output drive current. In this embodiment, the number of bias circuits 101 is equal to the number of current control modules 11, but this invention is not limited thereto. For example, when the number of bias circuits 101 and current control modules 11 is greater than 2, and the ratio of the number of bias circuits 101 to the number of current control modules 11 is greater than 0.5, the transient response time of the light-emitting diode driver 1 can be shortened.

[0052] Please refer to Figure 2In this embodiment, each current control module 11 includes a current control circuit 110 and a slew rate enhancement circuit 111. The current control circuit 110 is used to output the drive current, and the current value of the drive current can be adjusted according to the actual execution situation. In this embodiment, the current control circuit 110 includes one or more current control units C1 ( Figure 2 (Taking multiple current control units C1 as an example).

[0053] Please refer to Figure 2 and Figure 3 , Figure 3 A partial circuit diagram of the current control module according to an embodiment of the present invention. It should be noted that... Figure 3 The detailed electrical connection between the slew rate enhancement circuit 111 and the current control unit C1 is illustrated using only one current control unit C1 as an example, but the present invention is not limited thereto. Each current control unit C1 includes a transistor 110T, a first switching element SW1, and a second switching element SW2, but the present invention is not limited thereto.

[0054] like Figure 3 As shown, in this embodiment, the gate of transistor 110T is electrically coupled to the control node NB. One of the source and drain terminals of transistor 110T is grounded, and the other is electrically connected to a corresponding light-emitting diode 2. The control node NB is electrically connected to the output node NA of the corresponding bias circuit 101. When the bias voltage applied to the gate of transistor 110T is greater than a predetermined value, transistor 110T is turned on, thereby outputting a drive current to the corresponding light-emitting diode 2.

[0055] The first switching element SW1 is connected between the control node NB and the output node NA to control the conduction or cutoff of transistor 110T. Furthermore, the second switching element SW2 is connected between the control node NB and the ground terminal. When the first switching element SW1 is closed and the second switching element SW2 is open, the bias circuit 101 outputs a bias current to turn on transistor 110T. When the first switching element SW1 is open and the second switching element SW2 is closed, transistor 110T is cut off.

[0056] It is worth mentioning that, Figure 2In this embodiment, for each current control circuit 110, the gate terminals of all transistors 110T in the current control unit C1 are commonly coupled to the control node NB, and the transistors 110T are electrically connected to each other in parallel. Therefore, by controlling the states of the first switching element SW1 and the second switching element SW2 of the current control unit C1 respectively, the drive current value output by each current control circuit 110 can be determined, thereby controlling the brightness of each light-emitting diode 2. In one embodiment, a control circuit such as a pulse width modulation (PWM) circuit can be used to control the states of the first switching element SW1 and the second switching element SW2, but the invention is not limited to the embodiments provided herein.

[0057] It is worth noting that the larger the drive current value required by each current control circuit 110, the more transistors 110T need to be turned on. However, the parasitic capacitance of the gate of transistor 110T will increase the transient response time of the LED driver 1. Specifically, due to the parasitic capacitance of the gate of transistor 110T, the drive current value output by each current control circuit 110 is difficult to reach the preset current value during the limited conduction period. The more transistors 110T that need to be turned on, the greater the impact of parasitic capacitance on the transient response time.

[0058] like Figure 2 As shown, in this embodiment, by connecting any two bias circuits 101 in series with a resistive device 102, the bias currents output by the bias circuits 101 can compensate for each other, thereby reducing the impact of parasitic capacitance on transient response time. For example, when only the red LED 2R needs to be turned on, the bias currents output by the two bias circuits 101, which are electrically connected to the green LED 2G and the blue LED 2B respectively, can be transmitted to the current control circuit 110, which is electrically connected to the red LED 2R. In this way, the driving current value used to drive the red LED 2R can be increased rapidly.

[0059] It is worth mentioning that by appropriately adjusting the resistance value of each resistive device 102 connected between any two bias circuits 101, when one of the light-emitting diodes 2 (e.g., red light-emitting diode 2R) is driven, insufficient bias current supplied to the current control circuit 110 electrically connected to the other light-emitting diodes 2 (e.g., blue light-emitting diode 2B and green light-emitting diode 2G) can be avoided.

[0060] Furthermore, in this embodiment, each current control module 11 further includes a slew rate enhancement circuit 111 to reduce the impact of parasitic capacitance on the rate of increase of the drive current. Specifically, for each current control module 11, the slew rate enhancement circuit 111 is electrically coupled to the current control circuit 110 to output complementary currents.

[0061] refer to Figure 2 The output of the slew rate enhancement circuit 111 and the gate of each transistor 110T are jointly coupled to the control node NB. Thus, when the first switching element SW1 switches to the closed state, the slew rate enhancement circuit 111 outputs a complementary current to the gate of the corresponding transistor 110T until the bias voltage applied to the gate of the corresponding transistor 110T reaches a predetermined voltage value. It is worth noting that the gates of the transistors 110T are jointly coupled to the slew rate enhancement circuit 111. Therefore, the negative impact of the parasitic capacitance of the transistor 110T on the transient response of the LED driver 1 is mitigated.

[0062] Please refer to Figure 3 The slew rate enhancement circuit 111 in this embodiment of the invention includes a slew rate enhancement transistor T. SRE The invention relates to voltage setting circuit 111A, but is not limited thereto. In another embodiment, slew rate enhancement circuit 111 may include other elements to perform the same function and achieve the same result.

[0063] In this embodiment, the slew rate enhancement transistor T SRE It has a control gate terminal TG, a first terminal TA, and a second terminal TB. The first terminal TA can be a slew rate enhancement transistor T. SRE The source or drain endpoint. Furthermore, the slew rate enhancement transistor T... SRE The first terminal TA can serve as the output terminal of the slew rate enhancement circuit 111, and the first terminal TA and the gate terminal of transistor 110T are both coupled to the control node NB. Furthermore, the slew rate enhancement transistor T... SRE The second terminal TB can be electrically coupled to the power supply terminal P1.

[0064] Voltage setting circuit 111A is coupled to slew rate enhancement transistor T. SRE The control gate terminal TG is used to apply a preset bias voltage to the slew rate enhancement transistor T. SRE The control gate terminal. For example... Figure 3 As shown, the voltage setting circuit 111A includes a first transistor T1 and a second transistor T2.

[0065] The first transistor T1 has a first gate terminal T10, a first source terminal T11, and a first drain terminal T12. The second transistor T2 has a second gate terminal T20, a second source terminal T21, and a second drain terminal T22. For example... Figure 3 As shown, the first source terminal T11 of the first transistor T1 is electrically coupled to the second drain terminal T22 of the second transistor T2. Furthermore, the first drain terminal T12 of the first transistor T1 and the slew rate enhancement transistor T... SRE The control gate terminal TG is coupled to the current source P2.

[0066] The preset bias voltage will be continuously applied to the slew rate enhancement transistor T. SRE The control gate terminal TG. When the first switching element SW1 switches to the closed state, the initial bias voltage between the control gate terminal TG and the first terminal TA is greater than that of the slew rate enhancement transistor T. SRE The threshold voltage. Therefore, the slew rate enhancement transistor T... SRE The transistor is turned on, and a complementary current is output to the control node NB. The potential of the control node NB (or the first terminal TA) gradually increases. When the bias voltage between the control gate terminal TG and the first terminal TA is less than that of the enhancement-mode transistor T... SRE At the critical voltage, the enhancement transistor TSRE It is cut off and will not supply complementary current.

[0067] Therefore, the preset bias voltage is assumed to be Vg, the bias voltage applied to the first terminal TA or the control node NB is assumed to be Vx, and the slew rate enhancement transistor T is... SRE The critical voltage is assumed to be Vth. Under the current bias voltage Vg, the bias voltage Vx applied to the first terminal TA (or control node NB) and the critical voltage Vth satisfy the following relationship: Vth > (Vg - Vx), and the slew rate enhancement transistor T... SRE It will be cut off, and the complementary current will not be supplied to the first terminal TA.

[0068] For all current control modules 11, the bias voltage applied to the first terminal TA or control node NB will be affected by the bias current output by each bias circuit 101 and the slew rate enhancement transistor T. SRE The complementary current output increases rapidly, thereby increasing the rate of increase of the drive current output to the corresponding LED 2.

[0069] Please refer to Figure 4 and Figure 5 , Figure 4 This is a waveform diagram of the driving signal according to an embodiment of the present invention. Figure 5 This is a comparative example and a schematic diagram of the current waveform of an embodiment of the present invention. For example... Figure 4 As shown, an example is given using one duty cycle of the drive signal. During the conduction period T on The first switching element SW1 is in the closed state, and the second switching element SW2 is in the open state.

[0070] like Figure 5 As shown, curve A1 represents the current waveform of the LED driver, which is the current change of the drive signal in one operating cycle according to an embodiment of the present invention. Furthermore, curve B1 represents the current waveform of the driver in a comparative example, which is the current change of the drive signal in one operating cycle according to a comparative example, wherein the driver in the comparative example does not include any slew rate enhancement circuitry.

[0071] like Figure 5 As shown, during the conduction period T on The rising slope of curve A1 is greater than that of curve B1. That is, compared to the comparison example, during the conduction period T of the drive signal... on Within this embodiment of the invention, the rate of increase of the drive current output by the LED driver 1 is relatively large, thereby increasing the drive current and resulting in a larger current value. This improves the transient response time of the LED driver 1 in this embodiment of the invention.

[0072] The light-emitting diode driver 1 of this embodiment can be implemented in the backlight module of a light-emitting diode display device (hereinafter referred to as "LED display device") or a liquid crystal display device, but the present invention is not limited to the examples provided herein. Please refer to Figure 6 , Figure 6 This is a schematic diagram of a display device according to an embodiment of the present invention. In this embodiment, the display device M1 is an LED display device. The display device M1 includes a pixel array PX and a light-emitting diode driver 1.

[0073] A pixel array PX can be disposed on a substrate S1 and includes multiple pixels PX1. Each pixel PX1 can be composed of light-emitting diodes 2 arranged to generate light beams of different colors, so that each pixel PX1 can output a mixed light beam. For example, the light-emitting diodes 2 can include a red light-emitting diode 2R, a blue light-emitting diode 2B, and a green light-emitting diode 2G, but the present invention is not limited thereto. By adjusting the brightness of each diode in the light-emitting diodes 2, the color of the mixed light beam (emitted from each pixel PX1) can be changed.

[0074] The components of LED driver 1 are as follows Figure 1 and Figure 2 As shown, details will not be repeated here. The LED driver 1 can configure and drive each LED 2 of each pixel PX1 in the display device M1. Since the brightness of each LED 2 is proportional to the applied driving current, the LED driver 1 can adjust the driving current applied to each LED 2, thereby controlling the color of the mixed light beam. The faster the transient response of the LED driver 1, the higher the color resolution of the display device M1.

[0075] Please refer to Figure 6 The current control module 11 of the LED driver 1 can be electrically connected to the LEDs 2 in each pixel PX1. As described above, in the LED driver 1 of this embodiment, by using a resistive bias network formed by a bias circuit 101 and a resistive device 102 connected in series, and by using a slew rate enhancement circuit 111, the negative impact of parasitic capacitance in each current control circuit 110 on the transient response time of the LED driver 1 can be reduced.

[0076] That is, the LED driver 1 can have a faster transient response speed. Therefore, during conduction, the current value of the driving current output by each LED 2 can quickly increase to a preset current value. In this way, the color accuracy and color resolution of the display device M1 in this embodiment of the invention are improved. In addition, the display device M1 in this embodiment of the invention can also have a wider color gamut.

[0077] In summary, in the LED driver and the display device using the LED driver provided by the present invention, by electrically coupling any two bias circuits 101 to each other through at least one resistive device 102, and electrically coupling the slew rate enhancement circuit 111 to the current control circuit 110 to output complementary currents, the LED driver 1 can have a fast transient response.

[0078] Specifically, the bias circuit 101 and the power supply element 102 together form a resistive bias network, which allows the bias currents output by different bias circuits 101 to compensate for each other, and reduces the negative impact of the parasitic capacitance of transistor 110T on the transient response time of LED driver 1.

[0079] Furthermore, in the LED driver 1 of this embodiment, the complementary current is output to the current control circuit 110 electrically connected to it via the slew rate enhancement circuit 111, which shortens the time it takes for the driving current value to rise to the preset current value. However, the standby current or static power consumption of the LED driver 1 does not increase significantly. When the LED driver 1 is provided in the display device M1, the color accuracy and color resolution of the display device M1 can be improved. In addition, the display device M1 of this embodiment can have a larger color gamut.

[0080] The foregoing description is an exemplary embodiment of the present invention and is for illustrative and descriptive purposes only. It is not intended to provide an exhaustive disclosure or to limit the invention to the precise form disclosed herein. In view of the foregoing teachings, numerous modifications and variations are possible.

[0081] The selection and description of the embodiments are intended to explain the principles of the invention and its practical application, enabling other skilled in the art to utilize the content and various embodiments of the invention and make various modifications to suit a specific intended use. Alternative embodiments will become apparent to those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A light-emitting diode driver, comprising: A drive module comprising multiple bias circuits and multiple resistive devices, wherein any two bias circuits are electrically coupled to each other through at least one of the resistive devices; and Multiple current control modules are respectively coupled to the bias circuit, wherein each current control module includes: A current control circuit for outputting a drive current; and A slew rate enhancement circuit is electrically coupled to the current control circuit and is used to output a complementary current.

2. The LED driver of claim 1, wherein the current control circuit comprises a plurality of transistors, the gate terminals of which are commonly coupled to the slew rate enhancement circuit.

3. The LED driver of claim 1, wherein the current control circuit includes at least one transistor, and the slew rate enhancement circuit includes a slew rate enhancement transistor having a control gate, a first terminal, and a second terminal; wherein a gate terminal of the at least one transistor and the first terminal of the slew rate enhancement transistor are coupled to a control node.

4. The LED driver of claim 3, wherein the slew rate enhancement circuit further includes a voltage setting circuit coupled to the control gate terminal of the slew rate enhancement transistor for applying a preset bias voltage to the control gate terminal of the slew rate enhancement transistor.

5. The LED driver of claim 4, wherein the voltage setting circuit includes a first transistor and a second transistor, a first source terminal of the first transistor is electrically coupled to a second drain terminal of the second transistor, and a first drain terminal of the first transistor and the control gate terminal of the slew rate enhancement transistor are jointly coupled to a current source.

6. The LED driver of claim 3, wherein the second terminal of the slew rate enhancement transistor is coupled to a power supply terminal.

7. The LED driver of claim 1, wherein each bias circuit includes an output node, and each resistive device is connected between the two output nodes of any two bias circuits.

8. The light-emitting diode driver of claim 7, wherein the current control circuit includes at least one transistor, the gate of which is coupled to a control node; wherein, Each current control module includes a first switching element, which is connected between the control node and the output node.

9. The LED driver of claim 1, wherein the driving module further includes a reference voltage circuit electrically coupled to the bias circuit.

10. The LED driver of claim 1, wherein one of the resistive devices is connected in series between every two bias circuits to form a resistive bias network.

11. The LED driver of claim 1, wherein the number of resistive devices is equal to or greater than the number of bias circuits.

12. The LED driver of claim 1, wherein the ratio of the number of bias circuits to the number of current control modules is greater than 0.

5.

13. A display device comprising: A pixel array comprising multiple pixels, wherein each pixel includes multiple light-emitting diodes (LEDs) for generating beams of different colors to output a mixed beam; and The light-emitting diode driver as claimed in claim 1, wherein the current control module is electrically connected to the light-emitting diode to control the color of the mixed light beam emitted by the pixel.

14. The display device of claim 13, wherein in each of the pixels, the light-emitting diodes comprise a red light-emitting diode, a blue light-emitting diode, and a green light-emitting diode.

15. The display device of claim 13, wherein the current control circuit comprises a plurality of transistors, the plurality of gate terminals of the transistors being commonly coupled to the slew rate enhancement circuit.

16. The display device of claim 13, wherein the current control circuit includes at least one transistor, the slew rate enhancement circuit includes a slew rate enhancement transistor having a control gate, a first terminal and a second terminal, and a gate and the first terminal of the at least one transistor are coupled to a control node.

17. The display device of claim 16, wherein the second terminal of the slew rate enhancement transistor is coupled to a power supply terminal.

18. The display device of claim 13, wherein each bias circuit includes an output node, and each resistive device is connected between the two output nodes of any two bias circuits to form a resistive bias network.

19. The display device of claim 18, wherein the current control circuit includes at least one transistor, a gate of the at least one transistor being coupled to a control node; wherein, Each current control module includes a first switching element, which is connected between the control node and the output node.

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