CN113939867B

CN113939867B - Driving method of backlight unit, backlight driving device and display device

Info

Publication number: CN113939867B
Application number: CN202080000414.8A
Authority: CN
Inventors: 管恩慧; 王志懋; 李咸珍; 李亮; 耿立华
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2020-03-27
Filing date: 2020-03-27
Publication date: 2022-10-25
Anticipated expiration: 2040-03-27
Also published as: WO2021189427A1; CN113939867A

Abstract

A driving method of a backlight unit (20), a backlight driving device (10) and a display device (100). The driving method of the backlight unit (20) can reduce noise generated by the whole system due to transmission of a control signal for driving the backlight unit (20), and specifically comprises the following steps: acquiring a first control signal (I1) (S110'); transmitting the first control signal (I1) to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal (I2) (S120'); the first signal processing circuit transmitting the second control signal (I2) to the backlight driving circuit (233, 333) performs frequency division and time delay processing to obtain a first operation circuit input signal, the first operation circuit input signal (S140 ') is provided to the first operation circuit of the backlight driving circuit (233, 333), and the second control signal (I2) is transmitted to the second operation circuit of the backlight driving circuit (233, 333) for outputting the backlight driving signal (L1) (S130').

Description

Driving method of backlight unit, backlight driving device and display device

Technical Field

Embodiments of the present disclosure relate to a driving method of a backlight unit, a backlight driving apparatus, and a display apparatus.

Background

An LCD (Liquid Crystal Display) is a non-self-luminous Display device using Liquid Crystal as a material, and includes a Liquid Crystal panel and a backlight unit disposed at a back side of the Liquid Crystal panel, the backlight unit providing light required for Display. The liquid crystal is an organic compound between solid and liquid, and has the liquidity of liquid and the optical anisotropy of crystals at normal temperature, and can be changed into a transparent liquid when heated and a crystallized turbid solid when cooled. Under the action of the electric field, the liquid crystal molecules are arranged to change, so that the incident light beam penetrates through the liquid crystal to generate intensity change, and the intensity change is further represented as light and shade change through the action of the polarizer. Therefore, the brightness change of the light from the backlight unit can be realized by controlling the liquid crystal electric field in each pixel unit in the liquid crystal panel, thereby achieving the purpose of information display.

Disclosure of Invention

At least one embodiment of the present disclosure provides a driving method of a backlight unit, including: acquiring a first control signal, wherein the frequency of the first control signal is a first frequency; transmitting the first control signal to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal; and transmitting the second control signal to a first signal processing circuit of a backlight driving circuit for frequency division and time delay processing to obtain a first operation circuit input signal, providing the first operation circuit input signal to the first operation circuit of the backlight driving circuit, and transmitting the second control signal to a second operation circuit of the backlight driving circuit for outputting the backlight driving signal, wherein the frequency of the second control signal is a second frequency, and the first frequency is not equal to the second frequency.

For example, in a driving method of a backlight unit provided in at least one embodiment of the present disclosure, transmitting the first control signal to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal includes: performing frequency multiplication modulation on the first control signal, and increasing the first frequency to the second frequency to obtain a second control signal; or performing frequency division modulation on the first control signal, and reducing the first frequency to the second frequency to obtain the second control signal.

For example, in a driving method of a backlight unit provided in at least one embodiment of the present disclosure, transmitting the second control signal to a first signal processing circuit of the backlight driving circuit to perform frequency division and time delay processing to obtain the first operating circuit input signal includes: performing N-division modulation on the second control signal transmitted to the first signal processing circuit to obtain N third control signals, wherein each of the N third control signals has a third frequency, so as to reduce noise in the backlight driving circuit; performing delay modulation on the N third control signals to obtain N fourth control signals, wherein a frequency obtained by superimposing fourth frequencies of the N fourth control signals is the same as the second frequency of the second control signal; wherein the first operational circuit input signal comprises the N fourth control signals, the fourth frequency is equal to the third frequency, and N is an integer greater than or equal to 2.

For example, in a driving method of a backlight unit according to at least one embodiment of the present disclosure, the first operating circuit includes N inductors, and the N fourth control signals are transmitted to the N inductors.

For example, in a driving method of a backlight unit provided in at least one embodiment of the present disclosure, performing delay modulation on the N third control signals to obtain N fourth control signals includes: delaying one of the N third control signals by a natural number of third control signal periods as one of the N fourth control signals; sequentially delaying the N-1 third control signals by k/N periods of the third control signals to obtain the rest N-1 fourth control signals; wherein k is a positive integer greater than or equal to 1 and less than or equal to N-1.

For example, at least one embodiment of the present disclosure provides a driving method of a backlight unit further including: before the second control signal is transmitted to the first signal processing circuit and the second operating circuit, the second control signal is transmitted to a second signal processing circuit of the backlight driving circuit, amplitude and/or waveform modulation is performed on the second control signal through the second signal processing circuit, and the processed second control signal is transmitted to the first signal processing circuit and the second operating circuit.

At least one embodiment of the present disclosure also provides a backlight driving apparatus including: signal transmission end, signal line and backlight driver board. The signal sending end is configured to send out a first control signal, and the first control signal has a first frequency; one end of the signal line is connected with a signal sending end, and the signal line is configured to transmit the first control signal; the backlight driving board comprises a signal receiving end, a signal modulation circuit and a backlight driving circuit, wherein the other end of the signal wire is connected with the signal receiving end, the signal receiving end is configured to receive the first control signal from the signal wire and transmit the first control signal to the signal modulation circuit for frequency conversion modulation processing so as to obtain a second control signal, the backlight driving circuit comprises a first signal processing circuit, a first operating circuit and a second operating circuit, the first signal processing circuit is configured to receive the second control signal and perform frequency division and time delay processing on the second control signal so as to obtain a first operating circuit input signal and provide the first operating circuit input signal for the first operating circuit, and the second operating circuit is configured to receive the second control signal and output a backlight driving signal; wherein the second control signal has a second frequency, the first frequency being different from the second frequency.

For example, in a backlight driving apparatus provided in at least one embodiment of the present disclosure, the signal modulation circuit includes a frequency multiplier configured to perform frequency multiplication modulation on the first control signal, and increase the first frequency to the second frequency to obtain the second control signal.

For example, in a backlight driving apparatus provided in at least one embodiment of the present disclosure, the signal modulation circuit includes a first frequency divider configured to perform frequency division modulation on the first control signal, and reduce the first frequency to the second frequency to obtain the second control signal.

For example, in a backlight driving apparatus provided in at least one embodiment of the present disclosure, the first signal processing circuit includes a second frequency divider and a delay circuit, the second frequency divider is configured to perform divide-by-N modulation on the second control signal transmitted to the first signal processing circuit to obtain N third control signals, where each of the N third control signals has a third frequency, so as to reduce noise in the backlight driving circuit; the delay circuit is configured to perform delay modulation on the N third control signals to obtain N fourth control signals, and a frequency obtained by superimposing a fourth frequency of the N fourth control signals is the same as the second frequency of the second control signal; the first operation circuit input signal comprises the N fourth control signals, the fourth frequency is equal to the third frequency, and N is an integer greater than or equal to 2.

For example, in a backlight driving apparatus further provided in at least one embodiment of the present disclosure, the first operating circuit includes N inductors, and the first signal processing circuit is connected to the first operating circuit to transmit the N third control signals to the N inductors, respectively.

For example, in a backlight driving apparatus further provided in at least one embodiment of the present disclosure, the first operating circuit further includes N control switches, the N control switches are respectively connected to the N inductors, and the N control switches are configured to apply the N fourth control signals to the N inductors, respectively.

For example, in a backlight driving apparatus further provided in at least one embodiment of the present disclosure, the delay circuit includes: the N-1 delay units are respectively configured to sequentially delay the N-1 third control signals by k/N third control signal periods to obtain N-1 fourth control signals, wherein one of the N-1 third control signals except the N-1 third control signals is delayed by a natural number of the third control signal periods to serve as one of the N fourth control signals, and k is a positive integer greater than or equal to 1 and less than or equal to N-1.

For example, in a backlight driving device further provided by at least one embodiment of the present disclosure, the backlight driving board further includes a second signal processing circuit, an input terminal of the second signal processing circuit is electrically connected to the signal modulation circuit, an output terminal of the second signal processing circuit is electrically connected to the first signal processing circuit and the second operation circuit, and the second signal processing circuit is configured to receive the second control signal before the second control signal is transmitted to the first signal processing circuit and the second operation circuit, and is configured to perform amplitude and/or waveform modulation on the second control signal and transmit the processed second control signal to the first signal processing circuit and the second operation circuit.

At least one embodiment of the present disclosure also provides a display device including: the backlight driving apparatus according to any of the above embodiments, and a backlight unit, wherein the backlight unit is coupled to the backlight driving apparatus to receive the backlight driving signal.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1A is a flowchart illustrating a driving method of a backlight unit according to an embodiment of the disclosure;

fig. 1B is another flowchart of a driving method of a backlight unit according to an embodiment of the disclosure;

fig. 2 is a flowchart illustrating a driving method of a backlight unit according to another embodiment of the present disclosure;

fig. 3 is a schematic block diagram of a backlight driving apparatus according to an embodiment of the disclosure;

fig. 4 is a schematic block diagram of a backlight driving apparatus according to another embodiment of the disclosure;

fig. 5A is a schematic block diagram of a backlight driving apparatus according to another embodiment of the disclosure;

fig. 5B is a schematic block diagram of a backlight driving apparatus according to another embodiment of the disclosure;

fig. 5C is a schematic block diagram of a backlight driving apparatus according to still another embodiment of the disclosure;

fig. 5D is a circuit diagram of a backlight driving circuit according to an embodiment of the disclosure;

fig. 5E is a waveform diagram illustrating operations of transistors and inductors in a backlight driving circuit according to an embodiment of the disclosure; and

FIG. 6 is a schematic block diagram of a display provided by an embodiment of the present disclosure.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. Also, the use of the terms "a," "an," or "the" and similar referents do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents.

The basic structure of the lcd device includes four parts, namely, an lcd panel and its driving circuitry, a backlight Unit (BLU) and its driving circuitry.

Currently, the backlight unit of the lcd device can be of a side-lit type or a direct-lit type, and the direct-lit type generally uses an LED (Light Emitting Diode) as a Light source. In order to realize the light emitting stability of the LED, a constant current driving design is generally adopted. For example, each LED light bar comprises a plurality of LEDs connected in series, and the cathodes of the LEDs of the light bar are connected to a current sampling circuit in the backlight driving circuit, and the current sampling circuit monitors the current stability of the LED light bar in real time. The current sampling Circuit converts the current change into a voltage signal and feeds the voltage signal back to an LED drive IC (Integrated Circuit) in the backlight drive Circuit, and then the voltage signal is fed back to a DC/DC (Direct current-Direct current) Circuit in the backlight drive Circuit by the LED drive IC, and the DC/DC Circuit adjusts the output voltage input to the LED lamp bar after receiving the control signal, so that the current stabilizing effect of the LED lamp bar is realized. The backlight drive circuit is powered by an external DC power supply, typically 24V. The DC/DC circuit is generally implemented by a Boost circuit, which boosts the input voltage 24V of the DC power supply to a desired voltage. Meanwhile, in order to control and modulate the backlight brightness of the LED light bar, the backlight driving circuit needs to receive a backlight enable signal BL _ EN and a pulse width modulation signal PWM to generate a backlight driving signal.

On one hand, in order to ensure the brightness regulation capability of the backlight driving circuit on the LEDs of the backlight unit, the frequency of the pulse width modulation signal PWM is generally about 1KHz, and the pulse width modulation signal PWM is transmitted to the backlight driving circuit through a signal line. However, noise on the signal line with a frequency of about 1KHz generated by the PWM signal is easily coupled to the horn line adjacent to the signal line, resulting in bottom noise of the whole system. On the other hand, for example, a DC/DC circuit in the backlight driving circuit includes a component such as an inductance element, and noise is easily generated even after an electric signal of a certain frequency is applied to the inductance.

The above-mentioned noise seriously affects the user hearing experience. Therefore, the following method is proposed for reducing noise due to the above signal.

The pulse width modulated signal PWM is increased beyond the audible range of the human ear (i.e., above 20 KHz) to reduce noise. However, this method may reduce the brightness adjustment capability of the backlight driving circuit for the LED.

Alternatively, the horn wire is disposed at a position distant from the signal wire to reduce noise. However, the backlight driving circuit is usually disposed at a position that is vertically or horizontally symmetrical to the whole system, and in order to ensure the hearing experience of the user, the speaker is usually disposed at a position that is horizontally symmetrical to the whole system, and it is difficult to avoid the position of the signal line, which is limited by this method.

Or, the backlight driving circuit is close to the sending end of the pulse width modulation signal PWM, and the length of the signal wire is shortened to reduce noise. However, this method may increase the distance from the backlight driving circuit to the LED, thereby affecting the transmission of the backlight driving signal.

Alternatively, the signal lines may be shielded to reduce noise. However, this method reduces the noise coupled to the horn wire to some extent, but increases the process difficulty and cost of the liquid crystal display device.

At least one embodiment of the present disclosure provides a driving method of a backlight unit, including: acquiring a first control signal, wherein the frequency of the first control signal is a first frequency; transmitting the first control signal to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal; and transmitting the second control signal to a first signal processing circuit of the backlight driving circuit to perform frequency division and time delay processing so as to obtain a first operation circuit input signal, providing the first operation circuit input signal to a first operation circuit of the backlight driving circuit, and transmitting the second control signal to a second operation circuit of the backlight driving circuit to output the backlight driving signal, wherein the frequency of the second control signal is a second frequency, and the first frequency is not equal to the second frequency. The method of the embodiment can reduce the noise generated by the signal line and the backlight driving circuit, and does not influence the brightness adjusting capability of the backlight driving circuit on the light emitting unit (such as LED) in the backlight unit.

At least one embodiment of the present disclosure also provides a backlight driving apparatus and a display apparatus including the same, which can perform the driving method of the backlight unit.

Embodiments of the present disclosure and examples thereof are described in detail below with reference to the accompanying drawings.

At least one embodiment of the present disclosure provides a driving method of a backlight unit, and fig. 1A is a flowchart of the driving method of the backlight unit according to an embodiment of the present disclosure.

As shown in fig. 1A, the driving method includes steps S110 to S130.

Step S110: a first control signal is acquired.

In this example, the frequency of the first control signal is a first frequency. The first control signal is transmitted to the backlight driving board through the signal line, and the first control signal generates noise with a first frequency on the signal line.

A display panel driving circuit in a liquid crystal display device includes a Timing Controller (TCON) PCB (abbreviated as TCON board), for example, in some examples, a first control signal is provided by the TCON board, for example, the first control signal is a pulse width modulation signal PWM. The TCON board and the backlight driving board are connected through a signal line, whereby the first control signal is supplied to the backlight driving board via the signal line.

For example, in some examples, the first frequency is in a range of 100Hz to 500Hz, and the first control signal generates noise on the signal line in a frequency range of 100Hz to 500Hz, respectively, which is not easily perceived by the human ear.

For example, in some examples, the first frequency is in the range of 20kHz to 22kHz, and the noise generated by the first control signal on the signal line is in the frequency range of 20kHz to 22kHz, respectively, where the noise is not readily or easily perceived by the human ear.

Step S120: and carrying out frequency conversion modulation on the first control signal to obtain a second control signal.

In this example, the frequency of the second control signal is a second frequency, and the first frequency is not equal to the second frequency.

For example, in some examples, the second control signal is also a pulse width modulation signal PWM accordingly, which is to be applied to the backlight driving board and to the LEDs as the light emitting unit in the backlight unit to adjust the brightness of the LEDs, and the frequency of the second control signal is the second frequency.

For example, in some examples, the second frequency ranges from 900Hz to 1100Hz, which may be selected according to the application scenario and the actual requirements, e.g., from 950Hz to 1050Hz.

For example, in some examples, the first frequency of the obtained first control signal is in a range of 100Hz to 500Hz, for example, 200Hz to 400Hz, and the first frequency is lower than the second frequency, then the first control signal needs to be subjected to frequency doubling modulation, and the first frequency is increased to the second frequency to obtain the second control signal; if the range of the first frequency of the obtained first control signal is 20kHz to 22kHz, for example, 20kHz to 21kHz, and the first frequency is greater than the second frequency, the first control signal needs to be subjected to frequency division modulation, and the first frequency is reduced to the second frequency, so as to obtain the second control signal.

Step S130: the second control signal is transmitted to the backlight driving circuit for generating the backlight driving signal.

For example, in some examples, the backlight driving circuit receives a second control signal and generates a backlight driving signal to make the LEDs emit light under the control of the second control signal.

A specific example of step S130 will be described in detail in fig. 2. According to the driving method of the backlight unit provided by the above embodiment of the present disclosure, by reducing or increasing the first frequency of the first control signal transmitted on the signal line, that is, reducing or increasing the frequency of the noise generated when the first control signal is transmitted on the signal line, the noise coupled to the horn line when the first control signal is transmitted on the signal line becomes less noticeable or undetectable to human ears; and performing frequency multiplication or frequency division modulation on the first control signal on the backlight driving board to obtain a second control signal, wherein the second control signal is used for controlling a light-emitting unit in the backlight unit to emit light.

For example, in other embodiments of the present disclosure, as shown in fig. 1B, another embodiment of the present disclosure further provides another driving method of the backlight unit, the driving method including steps S110 'to S140'.

Step S110': a first control signal is acquired.

In step S110', the frequency of the first control signal is the first frequency. The first control signal is transmitted to the backlight driving board through the signal line, and the first control signal generates noise with a first frequency on the signal line.

Step S120': and transmitting the first control signal to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal.

In step S120', the frequency of the second control signal is a second frequency, and the first frequency is not equal to the second frequency. For example, the signal modulation circuit may include a first frequency divider or multiplier to perform a frequency conversion modulation process on the first control signal.

For example, in some examples, transmitting the first control signal to the signal modulation circuit for frequency conversion modulation processing to obtain the second control signal includes: performing frequency multiplication modulation on the first control signal, and increasing the first frequency to the second frequency to obtain a second control signal; or performing frequency division modulation on the first control signal, and reducing the first frequency to the second frequency to obtain a second control signal. For example, if the first frequency of the obtained first control signal is within a range of 100Hz to 500Hz, for example, 200Hz to 400Hz, and the first frequency is lower than the second frequency, the first control signal needs to be frequency-doubled and modulated, and the first frequency is increased to the second frequency to obtain a second control signal; if the range of the first frequency of the acquired first control signal is 20kHz to 22kHz, for example, 20kHz to 21kHz, and the first frequency is greater than the second frequency, the first control signal needs to be subjected to frequency division modulation, and the first frequency is reduced to the second frequency to obtain the second control signal.

Step S130': the second control signal is transmitted to a second operation circuit of the backlight driving circuit for outputting the backlight driving signal.

For example, in step S130', the second operation circuit of the backlight driving circuit receives the second control signal and outputs the backlight driving signal under the control of the second control signal to make the LEDs emit light. For example, the second operation circuit may include a transistor, a capacitor, and the like, and the second control signal is transmitted to the transistor and the capacitor to control the transistor to be turned on or off and the capacitor to be charged or discharged. For example, the second control signal may be a pulse signal.

Step S140': the second control signal is transmitted to a first signal processing circuit of the backlight driving circuit to carry out frequency division and time delay processing so as to obtain a first operation circuit input signal, and the first operation circuit input signal is provided for a first operation circuit of the backlight driving circuit.

For example, in step S140', transmitting the second control signal to the first signal processing circuit of the backlight driving circuit for frequency division and time delay processing to obtain the first operation circuit input signal includes: performing N-frequency division modulation on the second control signal transmitted to the first signal processing circuit to obtain N third control signals, wherein the frequency of each of the N third control signals is a third frequency so as to reduce noise in the backlight driving circuit; performing delay modulation on the N third control signals to obtain N fourth control signals, wherein the frequency of the superposed fourth frequencies of the N fourth control signals is the same as the second frequency of the second control signal; the first operation circuit input signal comprises N fourth control signals, the fourth frequency is equal to the third frequency, and N is an integer greater than or equal to 2.

For example, in some examples, the first signal processing circuit may include a second frequency divider that performs divide-by-N modulation on the second control signal and a delay unit that performs delay modulation on the N third control signals.

For example, in some examples, the first operating circuit is electrically connected to the first signal processing circuit, the first operating circuit includes N inductors, and the N fourth control signals are transmitted to the N inductors so that the N inductors operate normally.

According to the driving method of the backlight unit provided by the above embodiment of the present disclosure, by reducing or increasing the first frequency of the first control signal transmitted on the signal line, noise coupled to the horn line when the first control signal is transmitted on the signal line becomes less noticeable or undetectable to human ears; and transmitting the second control signal to a first signal processing circuit of the backlight driving circuit for frequency division and time delay processing, and reducing the noise of the backlight driving circuit under the condition of ensuring the normal work of the backlight driving circuit.

Fig. 2 is a flowchart of a driving method of a backlight unit according to another embodiment of the disclosure.

As shown in fig. 2, compared to the embodiment shown in fig. 1A, the method of this embodiment includes steps S231 to S233 in addition to steps S210 to S230 in step S230.

Step S231: and performing N-frequency division modulation on the second control signal transmitted to the backlight driving circuit to obtain N third control signals. The frequency of the third control signal is a third frequency to reduce noise generated by the backlight driving circuit.

For example, in some examples, the backlight driving Circuit includes a current sampling Circuit, an LED driving IC, and a DC/DC Circuit, the current sampling Circuit converts a current variation of the LED light bar into a voltage signal and feeds the voltage signal back to the LED driving IC (Integrated Circuit) in the backlight driving Circuit, and the voltage signal is fed back to the DC/DC Circuit in the backlight driving Circuit by the LED driving IC, and the DC/DC Circuit adjusts an output voltage input to the LED light bar after receiving the voltage signal; the LED drive IC receives the second control signal and the backlight enable signal BL _ EN and transmits the second control signal to the DC/DC circuit, and the DC/DC circuit receives the second control signal and then generates a backlight drive signal to adjust the brightness of the LED lamp bar.

The DC/DC circuit is generally implemented by an inductive DC/DC circuit, which mainly includes three different topology types: a Buck type DC/DC circuit (Buck circuit for short), a Boost type DC/DC circuit (Boost circuit for short), and a Buck-Boost type DC/DC circuit (Buck-Boost circuit for short). The inductive DC/DC circuit usually includes an inductive element, which is one of the main sources of noise in such circuits, if the second control signal is directly transmitted to the inductor, the second control signal will generate noise with a second frequency on the inductor, and then the third control signal is obtained by performing frequency division modulation on the second control signal, and then the third control signal is transmitted to the inductor, so as to reduce the noise generated by the inductor.

In this example, the backlight driving circuit includes an inductance type DC/DC circuit including N inductance elements. And performing N-frequency division modulation on the second control signal to obtain N third control signals, wherein the frequency of each of the N third control signals is equal and is a third frequency, the third frequency is a ratio of the second frequency to the N, the N is an integer greater than or equal to 2, and the range of the third frequency is 'second frequency/N'.

Step S232: and carrying out time delay modulation on the N third control signals to obtain N fourth control signals.

In this example, each of the N fourth control signals (i.e., the first operating circuit input signal) has the same frequency and is a fourth frequency, and the fourth frequency is the same as the third frequency, that is, the frequency of the N fourth control signals superimposed on the fourth frequency is the same as the second frequency of the second control signal. Therefore, the N fourth control signals are respectively transmitted to the N inductors, and the N inductors sequentially work under the control of the fourth control signals.

For example, in some examples, delay modulating the N third control signals to obtain the N fourth control signals includes: delaying one of the N third control signals by a natural number of third control signal periods to serve as one of the N fourth control signals; and sequentially delaying the N-1 third control signals for k/N third control signal periods to obtain the rest N-1 fourth control signals. For example, k is a positive integer greater than or equal to 1 and less than or equal to N-1. In other words, one of the N third control signals is directly taken as one of the N fourth control signals; and sequentially carrying out delay modulation on the rest N-1 third control signals to obtain the rest N-1 fourth control signals. For example, the remaining N-1 third control signals are sequentially delayed by k/N third control signal periods.

Step S233: and respectively transmitting the N fourth control signals to the N inductors.

In this example, the N fourth control signals each have the same frequency and are transmitted to the N inductors respectively, and under the condition that the N inductors are guaranteed to operate normally, the N inductors each generate noise with the fourth frequency, and since the fourth frequency is smaller than the second frequency, the noise generated by each inductor will be less noticeable to human ears, and thus the noise generated by the N inductors as a whole will also be less noticeable to human ears.

In this example, the backlight driving circuit further includes other circuit portions including other elements, such as capacitors, resistors, diodes, transistors, etc., which have functions such as rectification, switching, amplification, etc. The backlight driving circuit transmits the N fourth control signals to the N inductors, and simultaneously transmits the second control signal to other elements (such as gates of transistors) for generating the backlight driving signal.

For example, in some examples, the driving method of the backlight unit provided by the embodiments of the present disclosure further includes: before the second control signal is transmitted to the first signal processing circuit and the second operation circuit, the second control signal is transmitted to the second signal processing circuit of the backlight driving circuit, amplitude and/or waveform modulation is carried out on the second control signal through the second signal processing circuit, and the processed second control signal is transmitted to the first signal processing circuit and the second operation circuit. For example, the second signal processing circuit includes a backlight chip, an input terminal of the backlight chip receives the second control signal, and after the backlight chip performs amplitude and/or waveform modulation on the second control signal, the frequency of the second control signal is unchanged, and the amplitude and/or waveform thereof is modulated so that the components of the second operating circuit can work normally.

For example, in some examples, the backlight driving circuit includes 2 inductance elements, the second control signal received by the backlight driving circuit is a pulse width modulation signal PWM, the pulse width modulation signal PWM is a square wave signal with adjustable duty ratio, the frequency of the second control signal is a second frequency, and the second frequency is in a range of 900Hz to 1100Hz. And performing frequency division modulation on the second control signal to obtain 2 third control signals, wherein the frequency of each of the 2 third control signals is equal and is a third frequency, the third frequency is equal to 1/2 × the second frequency, and the range of the third frequency is 450 Hz-550 Hz, so that the noise generated by the first operating circuit is reduced.

For example, 2 third control signals are subjected to noise reduction modulation, and 2 fourth control signals are obtained. Directly taking one of the 2 third control signals as a fourth control signal; delaying the other of the 2 third control signals by 1/2 of the period of the third control signal to obtain another fourth control signal, wherein the frequency of each of the 2 fourth control signals is equal and is the fourth frequency.

And 2 fourth control signals are respectively transmitted to 2 inductors, each of the 2 inductors generates noise with a fourth frequency, and the range of the fourth frequency is 450 Hz-550 Hz, so that the noise generated by each inductor is not easy to be perceived by human ears. The noise generated by the 2 inductors has a difference of 1/2 of the period of the third control signal, when the duty ratio of the pulse width modulation signal PWM is 50%, for example, the third control signal is a square wave signal with a 50% duty ratio, the noise generated by the 2 inductors is a square wave signal with a 50% duty ratio and has a difference of 1/2 of the period of the third control signal, the frequency of the fourth control signal received by the 2 inductors after the frequency superposition is equal to the frequency of the second control signal, the noise generated by each inductor is reduced to a range that is not easily perceived by human ears, and the total inductive noise generated by the backlight driving circuit is also not easily perceived by human ears.

According to the driving method of the backlight unit provided by at least one embodiment of the present disclosure, by increasing the number of inductors in the backlight driving circuit, performing frequency division modulation on the second control signal according to the number of the inductors to obtain a third control signal with a reduced frequency, performing delay modulation on the third control signal to obtain a fourth control signal, and enabling each inductor to receive the fourth control signal with the reduced frequency, the frequency of noise generated by each inductor during operation is reduced, and the noise becomes less noticeable to human ears.

At least one embodiment of the present disclosure also provides a backlight driving apparatus for driving a backlight unit. The embodiment of the disclosure also provides a backlight driving device. The backlight driving device includes: signal transmission end, signal line and backlight driver board. The signal sending end is configured to send out a first control signal, and the first control signal has a first frequency; one end of the signal wire is connected with the signal sending end, and the signal wire is configured to transmit a first control signal; the backlight driving board comprises a signal receiving end, a signal modulation circuit and a backlight driving circuit, the other end of the signal wire is connected with the signal receiving end, the signal receiving end is configured to receive a first control signal from the signal wire and transmit the first control signal to the signal modulation circuit for frequency conversion modulation processing to obtain a second control signal, the backlight driving circuit comprises a first signal processing circuit, a first operation circuit and a second operation circuit, the first signal processing circuit is configured to receive the second control signal and carry out frequency division and time delay processing on the second control signal to obtain a first operation circuit input signal and provide the first operation circuit input signal for the first operation circuit, and the second operation circuit is configured to receive the second control signal and output the backlight driving signal; the second control signal has a second frequency, the first frequency being different from the second frequency.

Fig. 3 is a schematic block diagram of a backlight driving apparatus according to an embodiment of the disclosure, where the backlight driving apparatus 10 includes: a signal transmitting terminal 110, a signal line 120 and a backlight driving board 130.

The signal emitting terminal 110 is configured to emit a first control signal I1, the first control signal I1 having a first frequency.

For example, in some examples, the first control signal I1 is provided by a Timing Control (TCON) board, the TCON board includes a signal emitting terminal 110, the first control signal I1 generated by the TCON board is emitted by the signal emitting terminal 110 and transmitted via the signal line 120. The signal line 120 is configured to transmit a first control signal I1. The signal line 120 may be various types of signal lines, and the embodiment of the present disclosure is not limited thereto.

For example, in some examples, the first frequency is in the range of 100Hz to 500Hz, and the first control signal I1 accordingly generates noise on the signal line 120 in the frequency range of 100Hz to 500Hz, which is not easily perceived by human ears.

For example, in some examples, the first frequency is in the range of 18kHz to 22kHz, and the first control signal I1 correspondingly generates noise on the signal line 120 in the range of 18kHz to 22kHz, which is not easily or not perceptible to the human ear.

The backlight driving board 130 is configured to receive the first control signal I1 from the signal line 120 and perform frequency conversion modulation on the first control signal I1 to obtain a second control signal I2, so as to generate a backlight control signal L1. For example, the second operation circuit of the backlight driving board 130 is configured to receive the second control signal I2 and output the backlight control signal. For example, the second operation circuit may include a transistor, a capacitor, and the like, and the second control signal I2 is transmitted to the transistor and the capacitor to control the transistor to be turned on or off and the capacitor to be charged or discharged. For example, the second control signal I2 may be a pulse signal.

In this example, the second control signal I2 has the second frequency, and the first frequency is different from the second frequency, thereby preventing the control signal having the first frequency from generating noise having the first frequency by being transmitted through the signal line, but still providing the control signal having the second frequency required by the backlight unit.

In this example, the signal emitting terminal 110 is connected to the backlight driving board 130 through the signal line 120.

Fig. 4 is a backlight driving apparatus according to another embodiment of the disclosure. As shown in fig. 4, compared with the embodiment shown in fig. 3, the apparatus 20 of this embodiment includes a signal receiving terminal 231, a frequency converter 232 and a backlight driving circuit 233 in addition to the signal transmitting terminal 210, the signal line 220 and the backlight driving board 230.

The signal receiving terminal 231 is configured to receive the first control signal I1.

In this example, the signal receiving terminal 231 is connected to the signal transmitting terminal 210 through the signal line 220, and transmits the received first control signal to the frequency converter 232. The frequency converter 232 (i.e., a signal modulation circuit) is connected to the signal receiving end 231, and is configured to perform frequency conversion modulation on the first control signal I1 to obtain a second control signal I2.

For example, in some examples, the second frequency ranges from 900Hz to 1100Hz, which is a frequency at which the light emitting unit in the general backlight unit is driven to emit light. Nevertheless, in the embodiment of the present disclosure, the second frequency may also be selected according to the application scenario and the actual requirements.

For example, in some examples, the frequency converter 232 may be a frequency multiplier or a frequency divider as needed to multiply or divide the frequency of the received first control signal I1.

For example, in some examples, the frequency converter 232 is a frequency multiplier. The frequency converter 232 is configured to perform frequency doubling modulation on the first control signal I1 with a frequency in the range of 100Hz to 500Hz, and increase the first frequency to a second frequency to obtain a second control signal I2, for example, the second frequency is in the range of 900Hz to 1100Hz.

For example, in some examples, the frequency converter 232 is a frequency divider, referred to herein as a first frequency divider. The first frequency divider is configured to perform frequency division modulation on a first control signal I1 with a frequency in the range of 20 kHz-22 kHz, and reduce the first frequency to a second frequency to obtain a second control signal I2, wherein the second frequency is in the range of 1000 Hz-1100 Hz, for example.

The backlight driving circuit 233 is connected to the inverter 232, and configured to receive the second control signal to generate the backlight driving signal.

Fig. 5A is a backlight driving apparatus according to still another embodiment of the disclosure. As shown in fig. 5A, compared to the embodiment shown in fig. 4, the apparatus 30 of this embodiment includes, in addition to the signal transmitting terminal 310, the signal line 320 and the backlight driving board 330, the backlight driving board 330 includes a signal receiving terminal 331, a first frequency converter 332 (i.e., a signal modulation circuit) and a backlight driving circuit 333, and the backlight driving circuit 333 further includes a second frequency divider 334, a delay circuit 335 and N inductors 338. For example, the first operational circuitry includes N inductors 338. For example, the first signal processing circuit includes a second frequency divider 334 and a delay circuit 335.

The second frequency divider 334 is connected to the first frequency converter 332, and configured to perform N-division modulation on the second control signal transmitted to the backlight driving circuit 333 to obtain N third control signals I3.

In this example, each of the N third control signals I3 has an equal frequency and is a third frequency, the third frequency is a ratio of the second frequency to N, N is an integer greater than or equal to 2, the third frequency ranges from "the second frequency/N", and the third frequency is smaller than the second frequency, so as to reduce noise generated by the backlight driving circuit.

The delay circuit 335 is connected to the second frequency divider 334, and configured to perform delay modulation on the N third control signals I3 to obtain N fourth control signals I4, and transmit the N fourth control signals I4 to the N inductors 338, respectively. For example, the first operation circuit input signal includes N fourth control signals.

In this example, the frequency of each of the N fourth control signals I4 is equal and is the fourth frequency, and the frequency of the N fourth control signals after the fourth frequency is superimposed is the same as the second frequency of the second control signal.

For example, in some examples, delay circuit 335 includes N-1 delay cells. The N-1 delay units are respectively configured to sequentially delay the N-1 third control signals I3 by k/N third control signal periods to obtain N-1 fourth control signals I4, and one third control signal I3 except the N-1 third control signals I3 is delayed by a natural number of third control signal periods to serve as one of the N fourth control signals I4. In other words, one third control signal I3 of the N third control signals I3 is directly taken as one of the N fourth control signals I4; the N-1 delay units are respectively configured to sequentially delay and modulate the remaining N-1 third control signals I3 to obtain the remaining N-1 fourth control signals I4. Namely, the rest N-1 third control signals I3 are sequentially delayed by k/N third control signal periods I3, wherein k is a positive integer which is greater than or equal to 1 and less than or equal to N-1.

In this example, the N fourth control signals I4 each have the same frequency and are transmitted to the N inductors 338 at the fourth frequency, and under the condition that the N inductors 338 are ensured to operate normally, the N inductors 338 each generate noise with the fourth frequency, so as to achieve the purpose of reducing noise of the backlight driving circuit 333.

For example, in some examples, the first operation circuit of the backlight driving circuit 333 further includes N control switches 337, the N control switches 337 are arranged in one-to-one correspondence with the N inductors, and are connected to the delay circuit 335 and the N inductors 338, and configured to control whether to apply the N fourth control signals to the N inductors 338, so that the N inductors work in turn to ensure the normal operation of the backlight driving circuit 333. That is, the effect of the N inductors operating in turn is the same as the effect of one inductor operating under the control of the second control signal having the second frequency, but the noise generated by the inductors can be reduced to a range that is not easily perceived by human ears.

In this example, the second operation circuit of the backlight driving circuit 333 includes other elements 341, such as a capacitor, a resistor, a diode, a transistor, and the like, which have functions such as rectification, switching, amplification, and the like. The backlight driving circuit board 330 transmits the second control signal I2 to other elements (e.g., gates of transistors) for generating the backlight driving signal L1. For example, the second control signal I2 is transmitted to the transistor and the capacitor to control the transistor to be turned on or off and the capacitor to be charged or discharged. For example, the second control signal I2 may be a pulse signal.

For example, as shown in fig. 5B, in an example of the present embodiment, the backlight driving circuit 333 includes a second frequency divider 334, a delay circuit 335, and two inductors, which are a first inductor 340 and a second inductor 339, respectively.

The second frequency divider 334 is connected to the first frequency converter 332 and configured to perform frequency division modulation on the second control signal I2 transmitted to the backlight driving circuit 333 by 2 to obtain 2 third control signals I3 (i.e., the third control signal I3-1 and the third control signal I3-2). The 2 third control signals I3 are each equal in frequency and have a third frequency equal to 1/2 × the second frequency, the third frequency ranges from 450Hz to 550hz, and the sum of the superposition of the 2 third frequencies is equal to the second frequency.

The delay circuit 335 is connected to the second frequency divider 334, and configured to perform delay modulation on the 2 third control signals, so as to obtain 2 fourth control signals I4 (i.e., the fourth control signal I4-1 and the fourth control signal I4-2), and transmit the 2 fourth control signals I4 to the 2 inductors (the first inductor 340 and the second inductor 339), respectively.

For example, in this example, delay circuit 335 includes 1 delay cell 336. Directly taking one third control signal I3-1 in 2 third control signals (the frequency of which is the third frequency) as a fourth control signal I4-1; another of the 2 third control signals is delayed by 1/2 of the third control signal period by the delay unit 336, so as to obtain another fourth control signal I4-2, and 2 fourth control signals I4 each have the same frequency and the fourth frequency. The 2 fourth control signals I4 are respectively transmitted to the 2 inductors, and the 2 inductors each generate noise with a fourth frequency, for example, the fourth frequency ranges from 450Hz to 550Hz, so that the noise generated by each inductor is not easily perceived by human ears. When the second control signal is a pulse width modulation signal PWM with a duty ratio of 50%, for example, the third control signal is a square wave signal with a duty ratio of 50%, the noises generated by the 2 inductors are all square wave signals with a duty ratio of 50% and have a difference of 1/2 of the period of the third control signal, the frequency of the fourth control signal received by the 2 inductors after frequency superposition is equal to the frequency of the second control signal, the noise generated by each inductor is reduced to a range that is not easily perceived by human ears, and the total inductive noise generated by the backlight driving circuit is also not easily perceived by human ears.

In this example, the backlight driving circuit 333 further includes two control switches, which are a first control switch 337 and a second control switch 338, respectively, the first control switch 337 is connected to the delay circuit 335 and the first inductor 340, and is configured to control whether to apply the fourth control signal I4-1 to the first inductor 340; the second control switch 338 is connected to the delay circuit 335 and the second inductor 339, and is configured to control whether the fourth control signal I4-2 is applied to the second inductor 339, so as to realize alternate operation of the two inductors, such that the backlight driving circuit 333 can normally operate.

In this example, the backlight driving circuit 333 further includes other elements 341, such as capacitors, resistors, diodes, transistors, etc., which have functions such as rectification, switching, amplification, etc. The second control signal I2 is transmitted to other elements (e.g., gates of transistors) for generating the backlight driving signal L1.

For example, as shown in fig. 5C, in one example of the present embodiment, the backlight driving circuit 30 further includes a second signal processing circuit 350, as compared with the embodiment shown in fig. 5B. The second signal processing circuit 350 is electrically connected to the first inverter 332 and the backlight driving circuit 333. Specifically, the input terminal of the second signal processing circuit 350 is electrically connected to the signal modulation circuit, and the output terminal of the second signal processing circuit 350 is electrically connected to the first signal processing circuit (i.e., the second frequency divider 334) and the second operation circuit (i.e., the other element 341). The second signal processing circuit 350 is configured to receive the second control signal I2 before the second control signal I2 is transmitted to the first signal processing circuit and the second operation circuit, and is configured to perform amplitude and/or waveform modulation on the second control signal I2 and transmit the processed second control signal I2 to the first signal processing circuit (e.g., the second frequency divider 334) and the second operation circuit (e.g., the other element 341). For example, the second signal processing circuit includes a backlight chip, an input terminal of the backlight chip receives the second control signal I2, and after the backlight chip performs amplitude and/or waveform modulation on the second control signal I2, the frequency of the second control signal I2 is unchanged, and the amplitude and/or waveform thereof is modulated so that the components of the second operating circuit can normally operate.

For example, fig. 5D is a circuit diagram of a backlight driving circuit provided in fig. 5C; fig. 5E is a waveform diagram illustrating operations of a transistor and a first inductor in a backlight driving circuit according to an embodiment of the disclosure.

As shown in fig. 5D and 5E, the other elements 341 include a transistor 3411, a diode 3413, and a capacitor 3412. The transistor 3411 and the second frequency divider 334 are electrically connected to the second signal processing circuit 350, respectively. The second control signal I2 is provided to the second frequency divider 334 and the transistor 3411 after amplitude and/or waveform modulation by the second signal processing circuit 350.

For example, the second control signal I2 is a pulse signal having a waveform as shown in fig. 5E, and the transistor 3411 is turned on and off alternately in one period under the control of the pulse signal. When the transistor 3411 is turned on, a current in the second operation circuit flows through the diode 3413 and charges the capacitor 3412; when the transistor 3411 is turned off, the capacitor 3412 is discharged, and the second operation circuit outputs the backlight driving signal L1 to the backlight unit 20.

For example, as shown in fig. 5D, the second frequency divider 334 receives the second control signal I2, frequency-divides and modulates the second control signal I2 to obtain 2 third control signals I3 (i.e., the third control signal I3-1 and the third control signal I3-2) to reduce noise, and transmits one of the third control signals I3 (as the fourth control signal I4-1) to the first inductor 340, and transmits the other third control signal I3 to the delay unit 336 for time-delay modulation, for example, the third control signal I3 is delayed by 1/2 third control signal period to obtain another fourth control signal I4-2, and the fourth control signal I4-2 is transmitted to the second inductor 339. As shown in fig. 5E, the working waveform of the fourth control signal I4-2 received by the second inductor 339 is the same as the working waveform of the fourth control signal I4-1 received by the first inductor 340, but the fourth control signal I4-2 is delayed by 1/2 fourth control signal period than the fourth control signal I4-1, so that the first inductor 340 and the second inductor 339 can work alternately to ensure the normal operation of the backlight driving circuit 333. Meanwhile, noise generated by the first inductor 340 and the second inductor 339 is not easily perceived by human ears.

As shown in fig. 5E, if the operating waveforms of the N inductors (e.g., the first inductor 340 and the second inductor 339) are synthesized, the frequency of the synthesized operating waveforms is the same as the frequency of the operating waveforms received by the transistor 3411, that is, the N inductors (e.g., the first inductor 340 and the second inductor 339) respectively operate under the control of the N fourth control signals, and the effect of the operation of one inductor under the control of the control signal having the waveform of the N inductors (e.g., the first inductor 340 and the second inductor 339) after the overlapping of the operating waveforms of the N inductors (e.g., the first inductor 340 and the second inductor 339) (the frequency of the control signal is equal to the second control signal) is the same, so as to ensure the normal operation of the backlight driving circuit 333.

For example, the transistor 3411 may be a P-type MOS transistor (Metal Oxide Semiconductor), an N-type MOS transistor, or the like, and embodiments of the present disclosure do not limit the type of the transistor 3411.

It should be noted that, for clarity and conciseness of representation, not all the constituent units of the backlight driving device 30 are shown in the embodiments of the present disclosure. In order to realize the necessary functions of the backlight detecting apparatus 30, those skilled in the art may provide and arrange other components according to specific needs, and the embodiment of the present disclosure is not limited thereto.

At least one embodiment of the present disclosure provides a display device. Fig. 6 is a schematic block diagram of a display device 100 according to an embodiment of the disclosure, where the display device 100 includes a backlight driving device 10, a backlight unit 20, and a display panel 30.

The backlight driving device 10 is the backlight driving device provided in any of the above embodiments. The backlight unit 20 includes a plurality of light emitting units (e.g., light emitting diodes). The backlight driving apparatus 10 is coupled to the backlight unit 20 and configured to provide a backlight driving signal to drive a plurality of light emitting units of the backlight unit 20 to emit light with required intensity.

For example, in some examples, the backlight unit 20 is configured to be coupled with the backlight driving apparatus 10 to receive a backlight driving signal. The backlight unit 20 is disposed at a back side (i.e., a side opposite to the display side) of the display panel 30 to provide a required backlight for a display operation of the display panel 30. The display panel 30 may be a liquid crystal display panel, an electronic paper display panel, or the like.

For example, in some examples, the backlight unit 20 may further include a functional film layer such as a light guide plate, a diffusion sheet, a brightness enhancement sheet, and the like, which is disposed on the light emitting side of the light emitting unit.

In one example of the present embodiment, the backlight unit includes a plurality of LEDs arranged in an array and divided into a plurality of regions, and the plurality of LEDs in each region may be independently controlled, whereby local dimming (local dimming) may be implemented. The backlight unit 20 controls and modulates the brightness of the LED backlight under the control of the received backlight driving signal, so that the display panel 30 located above the backlight unit 20 can display images.

The display device provided by at least one embodiment of the present disclosure may be implemented as: any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

The following points need to be explained:

(1) The drawings of the embodiments of the disclosure only relate to the structures related to the embodiments of the disclosure, and other structures can refer to the common design.

(2) Without conflict, embodiments of the present disclosure and features of the embodiments may be combined with each other to arrive at new embodiments.

The above is only a specific embodiment of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of changes or substitutions within the technical scope of the present disclosure, and shall be covered by the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. A driving method of a backlight unit, comprising:

acquiring a first control signal, wherein the frequency of the first control signal is a first frequency;

transmitting the first control signal to a signal modulation circuit for frequency conversion modulation processing to obtain a second control signal;

transmitting the second control signal to a first signal processing circuit of a backlight driving circuit for frequency division and time delay processing to obtain a first operating circuit input signal, providing the first operating circuit input signal to the first operating circuit of the backlight driving circuit, and

transmitting the second control signal to a second operation circuit of the backlight driving circuit for outputting a backlight driving signal,

the frequency of the second control signal is a second frequency, and the first frequency is not equal to the second frequency.

2. The driving method of the backlight unit according to claim 1, wherein transmitting the first control signal to a signal modulation circuit for a frequency conversion modulation process to obtain a second control signal comprises:

performing frequency multiplication modulation on the first control signal, and increasing the first frequency to the second frequency to obtain a second control signal; or alternatively

And performing frequency division modulation on the first control signal, and reducing the first frequency to the second frequency to obtain the second control signal.

3. The driving method of the backlight unit according to claim 1 or 2, wherein the transmitting the second control signal to the first signal processing circuit of the backlight driving circuit for frequency division and time delay processing to obtain the first operation circuit input signal comprises:

performing N-division modulation on the second control signal transmitted to the first signal processing circuit to obtain N third control signals, wherein each of the N third control signals has a third frequency, so as to reduce noise in the backlight driving circuit;

performing delay modulation on the N third control signals to obtain N fourth control signals, where a frequency obtained by superimposing fourth frequencies of the N fourth control signals is the same as the second frequency of the second control signal;

wherein the first operational circuit input signal comprises the N fourth control signals,

the fourth frequency is equal to the third frequency, and N is an integer greater than or equal to 2.

4. The driving method of the backlight unit according to claim 3, wherein the first operation circuit includes N inductors,

transmitting the N fourth control signals to the N inductors.

5. The driving method of the backlight unit according to claim 3, wherein the delay modulating the N third control signals to obtain N fourth control signals comprises:

delaying one of the N third control signals by a natural number of third control signal periods as one of the N fourth control signals;

sequentially delaying k/N periods of the third control signals for N-1 third control signals to obtain the rest N-1 fourth control signals;

wherein k is a positive integer greater than or equal to 1 and less than or equal to N-1.

6. The driving method of the backlight unit according to claim 1, further comprising: before the second control signal is transmitted to the first signal processing circuit and the second operation circuit, the second control signal is transmitted to a second signal processing circuit of the backlight driving circuit, the second signal processing circuit performs waveform modulation on the second control signal, and the processed second control signal is transmitted to the first signal processing circuit and the second operation circuit.

7. A backlight driving apparatus, comprising:

a signal emitting end configured to emit a first control signal, the first control signal having a first frequency;

a signal line, one end of which is connected to a signal emitting end, the signal line being configured to transmit the first control signal; and

the backlight driving board comprises a signal receiving end, a signal modulation circuit and a backlight driving circuit, the other end of the signal wire is connected with the signal receiving end, the signal receiving end is configured to receive the first control signal from the signal wire and transmit the first control signal to the signal modulation circuit for frequency conversion modulation processing to obtain a second control signal,

wherein the backlight driving circuit comprises a first signal processing circuit, a first operation circuit and a second operation circuit,

the first signal processing circuit is configured to receive the second control signal and frequency divide and delay the second control signal to obtain a first operational circuit input signal and provide the first operational circuit input signal to the first operational circuit,

the second operation circuit is configured to receive the second control signal and output a backlight driving signal;

wherein the second control signal has a second frequency, the first frequency being different from the second frequency.

8. The backlight driving apparatus according to claim 7, wherein the signal modulation circuit comprises a frequency multiplier,

the frequency multiplier is configured to perform frequency multiplication modulation on the first control signal and increase the first frequency to the second frequency to obtain the second control signal.

9. The backlight driving apparatus according to claim 7, the signal modulation circuit comprising a first frequency divider,

the first frequency divider is configured to perform frequency division modulation on the first control signal, and reduce the first frequency to the second frequency to obtain the second control signal.

10. The backlight driving device according to any one of claims 7 to 9,

the first signal processing circuit comprises a second frequency divider and a delay circuit,

the second frequency divider is configured to perform N-division modulation on the second control signal transmitted to the first signal processing circuit to obtain N third control signals, wherein each of the N third control signals has a third frequency, so as to reduce noise in the backlight driving circuit;

the delay circuit is configured to perform delay modulation on the N third control signals to obtain N fourth control signals, and a frequency of the N fourth control signals after superposition is the same as the second frequency of the second control signal;

11. The backlight driving apparatus according to claim 10, wherein the first operation circuit includes N inductors,

the first signal processing circuit is connected with the first operating circuit to transmit the N third control signals to the N inductors respectively.

12. The backlight driving apparatus according to claim 11, wherein the first operating circuit further comprises N control switches, the N control switches being respectively connected to the N inductors, the N control switches being configured to apply the N fourth control signals to the N inductors, respectively.

13. The backlight driving apparatus according to claim 10, wherein the delay circuit comprises: n-1 time-delay units are arranged in the circuit,

the N-1 time delay units are respectively configured to sequentially delay the N-1 third control signals by k/N third control signal periods to obtain N-1 fourth control signals,

wherein one of the third control signals except the N-1 third control signals is delayed by a natural number of periods of the third control signal as one of the N fourth control signals,

14. The backlight driving apparatus according to claim 7, wherein the backlight driving board further comprises a second signal processing circuit, an input terminal of the second signal processing circuit is electrically connected to the signal modulation circuit, an output terminal of the second signal processing circuit is electrically connected to the first signal processing circuit and the second operation circuit,

the second signal processing circuit is configured to receive the second control signal before the second control signal is transmitted to the first signal processing circuit and the second operating circuit, and is configured to perform waveform modulation on the second control signal and transmit the processed second control signal to the first signal processing circuit and the second operating circuit.

15. A display device, comprising:

a backlight driving device as claimed in any one of claims 7 to 14, and

a backlight unit, wherein the backlight unit is coupled with the backlight driving device to receive the backlight driving signal.