Display device

Abstract

The invention relates to a display device. The display device comprises a display panel and a backlight module. The backlight module comprises a light-emitting chip, a light-emitting driving circuit and a driving control circuit. The light-emitting driving circuit comprises a first switching tube, a second switching tube, a coupling inductor and a rectifying unit. The initial voltage input end of the light-emitting driving circuit is connected with initial voltage; the forward voltage output end of the light-emitting driving circuit is connected with the light-emitting chip, and the primary output end of the coupling inductor outputs a first voltage signal; the rectification unit is connected with the secondary input end or the secondary output end, and controls the secondary output end to provide a second voltage signal for the forward voltage output end; the driving control circuit is connected with the controlled end of the first switching tube, the controlled end of the second switching tube, the primary output end and the forward voltage output end, and the driving control circuit controls on or off of the first switching tube and on or off of the second switching tube according to the first voltage signal and the second voltage signal so as to adjust the second voltage signal.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to display devices. Background Technology

[0002] In the field of display technology, backlight control plays a crucial role. Backlighting not only provides the light source needed for display but also significantly improves display quality and energy efficiency through precise brightness adjustment. Common backlight control methods include PWM (Pulse Width Modulation) dimming, current control, and local dimming. These methods dynamically adjust backlight brightness according to the displayed content, thereby improving contrast, reducing energy consumption, and enhancing display performance.

[0003] COT (Constant On-Time) mode is a control architecture commonly used in Buck (step-down) backlight drivers. COT mode achieves regulated voltage or current output by comparing the output voltage ripple with a reference voltage and maintaining a fixed on-time within each cycle. COT mode offers advantages such as fast response, high efficiency under light loads, and simple control.

[0004] However, there is a problem that the main output ripple voltage of the Buck circuit is out of phase with the ripple voltage in the feedback loop, and therefore cannot participate in the normal COT mode feedback operation. Summary of the Invention

[0005] Therefore, it is necessary to provide a display device that can participate in normal COT mode to address the aforementioned technical problems.

[0006] This application provides a display device, including:

[0007] The display panel is configured to display images;

[0008] A backlight module is disposed on the light-incident side of the display panel, and the backlight module is configured to provide backlight; the backlight module includes:

[0009] LED chip;

[0010] A light-emitting driving circuit is configured with an initial voltage input terminal and a positive voltage output terminal. The initial voltage input terminal is used to receive an initial voltage; the positive voltage output terminal is connected to the light-emitting chip to provide the light-emitting chip with a second voltage signal greater than the initial voltage. The light-emitting driving circuit includes:

[0011] A first switching transistor, wherein the first terminal of the first switching transistor is connected to the initial voltage input terminal;

[0012] The second switch has a first end connected to the second end of the first switch, and the second end of the second switch is connected to the equivalent ground terminal.

[0013] A coupling inductor is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor is connected to the initial voltage input terminal, the second terminal of the first switch, and the first terminal of the second switch, respectively. The secondary output terminal of the coupling inductor is connected to the positive voltage output terminal of the light-emitting driving circuit. The primary output terminal of the coupling inductor is configured to output a first voltage signal.

[0014] A rectifier unit is connected to the secondary input terminal of the coupled inductor or to the secondary output terminal of the coupled inductor to control the secondary output terminal to provide a second voltage signal to the positive voltage output terminal;

[0015] The drive control circuit is connected to the controlled terminal of the first switch, the controlled terminal of the second switch, the primary output terminal of the coupling inductor, and the positive voltage output terminal, respectively. The drive control circuit is configured to control the first switch to turn on or off, and the second switch to turn on or off, according to the first voltage signal and the second voltage signal, so as to adjust the second voltage signal.

[0016] Beneficial effects: On the one hand, the light-emitting driving circuit includes a first switching transistor, a second switching transistor, a coupling inductor, and a rectifier unit. The primary input terminal of the coupling inductor is connected to the initial voltage input terminal, and the secondary input terminal of the coupling inductor is directly connected to the initial voltage input terminal or connected to the initial voltage input terminal through the rectifier unit. Therefore, when the light-emitting driving circuit provides the second voltage signal, it can superimpose the initial voltage and the isolation voltage generated by the coupling inductor itself, thereby achieving a boost effect where the second voltage signal is greater than the initial voltage, thus improving the conversion efficiency of the light-emitting driving circuit. On the other hand, the drive control circuit is connected to the controlled terminal of the first switch, the controlled terminal of the second switch, the primary output terminal and the positive voltage output terminal of the coupling inductor, respectively. The drive control circuit is configured to control the conduction or cutoff of the first switch and the second switch according to the first voltage signal and the second voltage signal, so as to adjust the second voltage signal. This can overcome the limitation that the second voltage signal cannot participate in the COT mode because the second voltage signal is out of phase with the first voltage signal. Under the combined action of the first voltage signal and the second voltage signal, the drive control circuit controls the conduction or cutoff of the first switch and the second switch, so that the second voltage signal can meet the positive voltage requirements of the light-emitting chip and improve the stability of the backlight drive.

[0017] In one embodiment, the drive control circuit is configured to control the first switch to turn on or off, and the second switch to turn on or off, based on the high-frequency component of the first voltage signal at the primary output terminal and the second voltage signal, thereby adjusting the second voltage signal.

[0018] Beneficial Effects: The high-frequency component of the first voltage signal is the ripple generated during the switching of the first and second switches. Its frequency is similar to the switching frequency, which can reflect the dynamic changes in the output voltage of the light-emitting driving circuit. In this embodiment, the energy transfer of the light-emitting driving circuit depends on the switching cycles of the first and second switches. The voltage changes of the first and second voltage signals also occur during the switching cycles of the first and second switches. Since the phase of the second voltage signal is opposite to that of the first voltage signal, the high-frequency component of the first voltage signal can more quickly and accurately reflect the voltage changes of the first and second voltage signals. The key to the feedback control of the light-emitting driving circuit by the driving control circuit lies in accurately capturing the real-time voltage fluctuations within the switching cycles of the first and second switches, thereby quickly correcting the imbalance of the coupled inductor during energy transfer. Therefore, by controlling the conduction or cutoff of the first and second switches based on the high-frequency component of the first voltage signal and the second voltage signal, the driving control circuit can improve the timeliness and accuracy of adjusting the second voltage signal.

[0019] In one embodiment, the drive control circuit includes:

[0020] A first filtering unit is connected to the primary output terminal. The first filtering unit is configured to filter out the low-frequency component of the first voltage signal and provide the high-frequency component of the first voltage signal.

[0021] The drive controller is connected to the first filter unit, the controlled terminal of the first switch, the controlled terminal of the second switch, and the positive voltage output terminal. It controls the first switch to turn on or off, and the second switch to turn on or off, based on the high-frequency component of the first voltage signal and the second voltage signal, and adjusts the second voltage signal.

[0022] Beneficial effects: The first filtering unit is connected to the primary output terminal, and the drive controller is connected to the first filtering unit, the controlled terminal of the first switching transistor, the controlled terminal of the second switching transistor, and the positive voltage output terminal. The first filtering unit can filter out the low-frequency component of the first voltage signal, thereby providing the high-frequency component of the first voltage signal to the drive controller. This allows the drive controller to receive the high-frequency component of the first voltage signal and the second voltage signal output from the positive voltage output terminal. Based on the high-frequency component of the first voltage signal and the second voltage signal, the drive controller can control the conduction or cutoff of the first switching transistor and the second switching transistor, thereby improving the sensitivity of the drive control circuit in adjusting the second voltage signal.

[0023] In one embodiment, the drive control circuit includes:

[0024] A first resistor, the first end of which is connected to the positive voltage output terminal;

[0025] The second resistor has its first end connected to the second end of the first resistor, and the second end of the second resistor is equivalently connected to the first end.

[0026] The first resistor and the second resistor are configured to perform voltage division processing on the second voltage signal to provide the low-frequency component of the second voltage signal to the drive controller;

[0027] The drive controller is configured to control the turning on or off of the first switch and the second switch based on the high-frequency component of the first voltage signal and the second voltage signal, wherein adjusting the second voltage signal includes:

[0028] The drive controller is configured to control the on / off state of the first switch and the second switch based on the high-frequency component of the first voltage signal and the low-frequency component of the second voltage signal, thereby adjusting the second voltage signal.

[0029] Beneficial Effects: By dividing the second voltage signal using the first and second resistors, the amplitude of the second voltage signal can be reduced. Since the first and second voltage signals are out of phase, reducing the amplitude of the second voltage signal is beneficial for increasing the amplitude of the final feedback voltage signal after the first and second voltage signals are superimposed, providing more effective feedback information. On the other hand, it can provide the low-frequency component of the second voltage signal to the drive controller. In this embodiment, the first voltage signal, in addition to including effective feedback information (effective ripple synchronized with the switching cycles of the first and second switching transistors), also contains invalid noise. Therefore, extracting the high-frequency component of the first voltage signal can accurately obtain effective feedback information and accurately capture the dynamic changes of the first and second voltage signals, improving the dynamic response speed of the drive control circuit. The second voltage signal, as the voltage signal output from the output terminal of the light-emitting drive circuit, participates in the regulation of the second voltage signal as part of the feedback signal. The function of the second voltage signal is to stably follow the static voltage level of the first voltage signal, rather than capturing its dynamic changes. The voltage of the second voltage signal is determined by magnetic coupling. If it is fed back at a high frequency, it will amplify the fluctuations caused by the "coupling difference," which is not conducive to the sensitive adjustment of the drive control circuit. Therefore, providing the low-frequency component of the second voltage signal to the drive controller can suppress low-frequency drift at the secondary output (from the output), ensuring static stability. This allows the drive control circuit to control the on / off states of the first and second switches based on the high-frequency component of the first voltage signal and the low-frequency component of the second voltage signal. This not only improves the sensitivity of the drive control circuit in regulating the second voltage signal but also corrects for low-frequency drift caused by increased core losses in the coupled inductor and slow initial voltage waveguide, ensuring the voltage stability of the second voltage signal.

[0030] In one embodiment, the drive control circuit further includes:

[0031] A third resistor, wherein the first end of the third resistor is connected to the first end of the second resistor, and the second end of the third resistor is connected to the drive controller;

[0032] The first capacitor is connected to the second terminal and the equivalent ground terminal of the third resistor, respectively.

[0033] Beneficial effects: The output impedance of the voltage divider network formed by the first and second resistors is reduced. Since the feedback terminal connected to the second and first ends of the first and second impedances of the drive controller is typically a high-impedance input, this embodiment connects a third resistor between the second and first ends of the first and second impedances and the drive controller. This avoids the impedance mismatch problem caused by direct connection between the drive controller and the second and first ends of the first and second impedances. If the voltage divider node connected to the second and first ends of the first and second resistors experiences high voltage due to initial voltage overshoot or component breakdown, the third resistor between the second and first ends of the first and second impedances and the drive controller can limit the current flowing into the drive controller, preventing large currents from damaging the drive controller and protecting it. Furthermore, the first capacitor is connected to the second terminal and the equivalent ground terminal of the third resistor respectively. Since the capacitive reactance of the first capacitor decreases as the frequency increases, connecting the first capacitor to the second terminal and the equivalent ground terminal of the third resistor respectively can provide a low-impedance path for high-frequency noise in the second voltage signal. This allows the high-frequency noise to pass through the first capacitor to the equivalent ground terminal, preventing it from reaching the drive controller. This avoids the drive controller misjudging the voltage changes of the first and second voltage signals under the interference of high-frequency noise in the second voltage signal, ensuring that the drive control circuit accurately adjusts the second voltage signal.

[0034] In one embodiment, the drive control circuit includes:

[0035] The second filtering unit is connected to the positive voltage output terminal. The second filtering unit is configured to filter out the high-frequency components of the second voltage signal and provide the low-frequency components of the second voltage signal to the drive controller.

[0036] Beneficial Effects: By setting a second filtering unit at the positive voltage output terminal of the light-emitting driving circuit, the second voltage signal output from the positive voltage output terminal of the light-emitting driving circuit can be filtered by the second filtering unit, thereby filtering out the high-frequency components of the second voltage signal and providing the low-frequency components of the second voltage signal to the drive controller. Since the first and second voltage signals are out of phase, when the drive controller superimposes the first and second voltage signals, the high-frequency components of the second voltage signal will reduce the amplitude of the superimposed signal, thus affecting the drive controller's ability to capture the dynamic changes of the first and second voltage signals and reducing the sensitivity of the drive controller. In this embodiment, by filtering out the high-frequency components of the second voltage signal through the second filtering unit, it is ensured that when the drive controller processes the high-frequency components of the first voltage signal and the low-frequency components of the second voltage signal, the interference caused by the high-frequency components of the second voltage signal to the high-frequency components of the first voltage signal can be reduced, thereby improving the sensitivity of the drive controller.

[0037] In one embodiment, the second filtering unit includes:

[0038] The fourth resistor is connected to the positive voltage output terminal and the first terminal of the first resistor, respectively.

[0039] The second capacitor is connected to the secondary input terminal and the first terminal of the first resistor, respectively.

[0040] Beneficial effects: The fourth resistor and the second capacitor constitute a low-pass filter unit. The fourth resistor is connected to the positive voltage output terminal and the first terminal of the first resistor, respectively. The second capacitor is connected to the secondary input terminal and the first terminal of the first resistor, respectively. Since the capacitive reactance of the second capacitor is inversely proportional to the signal frequency, its capacitive reactance is extremely high for the low-frequency components of the second voltage signal. The signal transmission line between the first terminal of the first resistor and the secondary input terminal of the coupling inductor can be approximated as an open circuit. In this case, the low-frequency components of the second voltage signal enter the drive controller through the fourth resistor and the first resistor. For the high-frequency components of the second voltage signal, the capacitive reactance of the second capacitor is extremely low. The signal transmission line between the first terminal of the first resistor and the secondary input terminal of the coupling inductor can be approximated as a short circuit. The high-frequency components of the second voltage signal are passed to the secondary input terminal of the coupling inductor, preventing the drive controller from accessing the high-frequency components of the second voltage signal, thus avoiding affecting the drive controller's judgment of the high-frequency components of the first voltage signal. This improves the response speed and accuracy of the drive controller in adjusting the second voltage signal.

[0041] In one embodiment, the second filtering unit includes:

[0042] The fifth resistor is connected to the positive voltage output terminal and the first terminal of the first resistor, respectively.

[0043] The third capacitor is connected to the first terminal and the equivalent ground terminal of the first resistor, respectively.

[0044] Beneficial Effects: The fifth resistor and the third capacitor form a low-pass filter unit. The fifth resistor is connected to both the positive output terminal and the first terminal of the first resistor. The third capacitor is connected to both the first terminal of the first resistor and the equivalent ground terminal. The second voltage signal is fed into the third capacitor through the fifth resistor. The fifth resistor limits the discharge current of the high-frequency components of the second voltage signal, preventing the high-frequency signal from directly entering the equivalent ground terminal from the positive output terminal through the third capacitor, which could cause an excessively large instantaneous current and damage the capacitor or the drive controller. For the low-frequency components of the second voltage signal, since the third capacitor has a capacitive reactance that is inversely proportional to the signal frequency, its capacitive reactance is much greater than the impedance of the fifth resistor. The low-frequency components of the second voltage signal experience almost no attenuation after passing through the fifth resistor into the drive controller, improving the quality of the low-frequency components of the second voltage signal received by the drive controller. For the high-frequency components of the second voltage signal, since the third capacitor has a capacitive reactance that is inversely proportional to the signal frequency, its capacitive reactance is much smaller than the impedance of the fifth resistor. The voltage division ratio X of the third capacitor and the fifth resistor is... C3 As R5 approaches zero, the high-frequency components of the second voltage signal are significantly attenuated. The fifth resistor amplifies the voltage division ratio difference between the high-frequency and low-frequency components of the second voltage signal, improving the filtering effect of the second filter unit in removing high-frequency components and outputting low-frequency components. Furthermore, the third capacitor is directly connected to the equivalent ground terminal, allowing the high-frequency components of the second voltage signal to be directly connected to the equivalent ground terminal, reducing interference from the high-frequency components of the second voltage signal to other signal transmission lines and improving the stability of the drive control circuit.

[0045] In one embodiment, the rectifier unit includes:

[0046] A cutoff diode, wherein the anode of the cutoff diode is connected to the secondary output terminal of the coupling inductor, and the cathode of the cutoff diode is connected to the forward voltage output terminal and the light-emitting chip;

[0047] Alternatively, the rectifier unit may include:

[0048] A rectifier switch, wherein the first terminal of the rectifier switch is connected to the initial voltage input terminal, and the second terminal of the rectifier switch is connected to the secondary input terminal of the coupling inductor;

[0049] A rectifier controller is connected to the first terminal, the second terminal, and the controlled terminal of the rectifier switch, respectively. The rectifier controller is configured to control the rectifier switch to turn on the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor when the primary coil of the coupled inductor is discharging, and to control the rectifier switch to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor when the primary coil of the coupled inductor is charging.

[0050] Beneficial effects: When the first switch is on and the second switch is off, the current through the primary winding of the coupling inductor increases linearly. Since the primary and secondary windings of the coupling inductor have opposite polarities, the induced voltage in the secondary winding causes the positive (cathode) voltage of the cutoff diode to be lower than the negative (cathode) voltage. The cutoff diode is reverse-biased and therefore cut off, preventing current flow. At this time, the light-emitting drive circuit stops outputting the second voltage signal to the light-emitting chip. When the first switch is off and the second switch is on, since the current in the primary winding of the coupling inductor does not change abruptly, the primary winding forms a freewheeling circuit under the action of the second switch. At this time, the induced voltage in the secondary winding causes the positive (cathode) voltage of the cutoff diode to be higher than the negative (cathode) voltage, causing the cutoff diode to switch to a forward-biased state, thus turning on. Based on this, the energy stored in the coupling inductor can be superimposed on the initial voltage connected to the secondary input terminal, and a second voltage signal can be provided to the light-emitting chip through the negative terminal of the cutoff diode, thereby achieving high-efficiency power supply.

[0051] The first terminal of the rectifier switch is connected to the initial voltage input terminal, and the second terminal of the rectifier switch is connected to the secondary input terminal of the coupled inductor. The rectifier controller is connected to the first terminal, the second terminal, and the controlled terminal of the rectifier switch. The rectifier controller is configured to control the rectifier switch to turn on the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor when the primary coil of the coupled inductor is discharged. This ensures that when the first switch is off and the second switch is on, the secondary input terminal of the coupled inductor is connected to the initial voltage. Under the influence of the change in magnetic flux caused by the increase in the current of the primary coil (primary winding) of the coupled inductor, an isolation voltage is induced, achieving voltage superposition. This results in the second voltage signal provided by the positive voltage output terminal being the sum of the initial voltage and the induced isolation voltage.

[0052] When the primary coil of the coupled inductor is charging, controlling the rectifier switch to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor ensures that, with the first switch on and the second switch off, the primary coil (primary winding) of the coupled inductor converts the electrical energy corresponding to the initial voltage into the magnetic field energy of the coupled inductor core. During this stage, the first switch conducts to establish the primary current of the primary coil (primary winding), allowing the core to accumulate sufficient magnetic field energy. This provides a preparatory step for the subsequent energy release of the secondary coil (secondary winding), preventing the rectifier switch from disrupting the energy storage process of the core, causing energy induction failure or energy waste, and achieving efficient storage of magnetic field energy and stable output of the second voltage signal.

[0053] In one embodiment, the light-emitting driving circuit further includes:

[0054] A fourth capacitor, wherein the first terminal of the fourth capacitor is connected to the primary output terminal, and the second terminal of the fourth capacitor is connected to the equivalent ground terminal;

[0055] The fifth capacitor has its first terminal connected to the positive voltage output terminal and its second terminal connected to the equivalent ground terminal.

[0056] Beneficial effects: The output of the first and second voltage signals of the light-emitting driving circuit relies on the periodic energy storage and release of the coupled inductor. When the first switch is on and the second switch is off, the primary coil (primary winding) of the coupled inductor stores energy through the magnetic core, while the secondary coil (secondary winding) does not generate induced energy. The first terminal of the fourth capacitor is connected to the primary output terminal, and the second terminal of the fourth capacitor is connected to the equivalent ground terminal; the first terminal of the fifth capacitor is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor is connected to the equivalent ground terminal, thus providing energy for the output of the first and second voltage signals. When the first switch is off and the second switch is on, the coupling inductor releases energy. The first voltage signal and the second voltage signal provide output energy through the coupling inductor, the fourth capacitor, and the fifth capacitor. Therefore, in this embodiment, the fourth capacitor connects the primary output terminal and the equivalent ground terminal, and the fifth capacitor connects the secondary output terminal and the equivalent ground terminal. This can compensate for the periodic ripple (frequency consistent with the switching frequency) in the first and second voltage signals caused by the intermittent energy transfer of the light-emitting driving circuit, as well as the voltage drop / overshoot that occurs when the light-emitting chip changes abruptly, thereby improving the stability of the light-emitting driving circuit. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 This is a schematic diagram of the structure of a display device according to an embodiment of this application;

[0059] Figure 2 This is one of the structural schematic diagrams of a backlight module in one embodiment of this application;

[0060] Figure 3 This is a second schematic diagram of the backlight module in one embodiment of this application;

[0061] Figure 4This is one of the structural schematic diagrams of the drive control circuit in one embodiment of this application;

[0062] Figure 5 This is a second schematic diagram of the drive control circuit in one embodiment of this application;

[0063] Figure 6 This is the third schematic diagram of the drive control circuit in one embodiment of this application;

[0064] Figure 7 This is one of the structural schematic diagrams of the second filtering unit in one embodiment of this application;

[0065] Figure 8 This is a second schematic diagram of the structure of the second filtering unit in one embodiment of this application;

[0066] Figure 9 This is one of the structural schematic diagrams of the rectifier unit in one embodiment of this application;

[0067] Figure 10 This is a second schematic diagram of the structure of the rectifier unit in one embodiment of this application;

[0068] Figure 11 This is a second schematic diagram of the structure of the light-emitting driving circuit in one embodiment of this application;

[0069] Figure 12 This is the third schematic diagram of the backlight module in one embodiment of this application;

[0070] Figure 13 This is the fourth schematic diagram of the backlight module in one embodiment of this application;

[0071] Figure 14 This is the fifth schematic diagram of the backlight module in one embodiment of this application;

[0072] Figure 15 This is the sixth schematic diagram of the backlight module in one embodiment of this application.

[0073] Explanation of icon numbers:

[0074] 11: Display panel; 12: Backlight module; 121: Light-emitting chip; 122: Light-emitting driving circuit; 1223: Coupled inductor; 1224: Rectifier unit; 2241: Rectifier controller; 123: Drive control circuit; 1231: First filter unit; 1232: Drive controller; 1233: Second filter unit. Detailed Implementation

[0075] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0076] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0077] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0078] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0079] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0080] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0081] In COT (Constant On-Time) mode, the voltage of the feedback node (FB) is required as a trigger signal to initiate each switching cycle. Therefore, the FB terminal needs to have a sufficiently large and correctly phased output voltage ripple to ensure that the comparator can operate accurately at the valley point.

[0082] However, in this embodiment, the light-emitting driving circuit provides a positive voltage to the light-emitting chip through the secondary output terminal and the positive voltage output terminal. To achieve COT mode, the feedback quantity needs to be taken from the positive voltage output terminal. Since the second voltage signal output from the positive voltage output terminal changes synchronously with the switching cycles of the first and second switching transistors: it exhibits a positive transition when the first switching transistor is off and a negative transition when the first switching transistor is on. Therefore, the waveform of the second voltage signal is out of phase with the actual voltage ripple—the actual voltage ripple rises during the first switching transistor's on period due to inductor charging and decreases during the first switching transistor's off period due to inductor freewheeling and capacitor discharging. This results in the ripple polarity obtained at the FB terminal being opposite to the valley trigger signal required for COT, causing the comparator in the drive control circuit to fail to operate at the correct time and making it impossible to work stably in COT mode.

[0083] Based on this, this application provides a display device. The display device in the embodiments of this application may be a television, mobile phone, tablet computer, monitor, vehicle central control screen, etc., and is not limited thereto.

[0084] See appendix Figure 1 and attached Figure 2 and attached Figure 3 , Figure 1A schematic diagram of the structure of a display device according to an embodiment of this application is shown. Figure 2 One of the structural schematic diagrams of the backlight module 12 in the embodiments of this application is shown. Figure 3 This is a second schematic diagram of the backlight module 12 in an embodiment of this application. An embodiment of this application provides a display device that may include a display panel 11 and a backlight module 12. The display panel 11 is configured for image display. The backlight module 12 is disposed on the light-incident side of the display panel 11. The backlight module 12 is configured to enhance backlighting.

[0085] The backlight module 12 in this embodiment may include a light-emitting chip 121.

[0086] The light-emitting chips 121 can be multiple, and some of the multiple light-emitting chips 121 can emit light of different colors. For example, the multiple light-emitting chips 121 can be multiple red light-emitting chips for emitting red light, multiple green light-emitting chips for emitting green light, and multiple blue light-emitting chips for emitting blue light. Another example is that the multiple light-emitting chips 121 can be multiple red light-emitting chips for emitting red light, multiple green light-emitting chips for emitting green light, multiple blue light-emitting chips for emitting blue light, and multiple yellow light-emitting chips for emitting yellow light. The method is not limited to these examples.

[0087] The backlight module 12 in this embodiment may include a light-emitting driving circuit 122. The light-emitting driving circuit 122 is configured with an initial voltage input terminal and a positive voltage output terminal. The output voltage input terminal is used to connect to the initial voltage Vin. The positive voltage output terminal is connected to the light-emitting chip 121 to provide the light-emitting chip 121 with a second voltage signal Vout2 that is greater than the initial voltage Vin.

[0088] The light-emitting driving circuit 122 in this embodiment may include a first switch Q1, a second switch Q2, a coupling inductor 1223, and a rectifier unit 1224. The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND.

[0089] The coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit 122. The primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1.

[0090] The rectifier unit 1224 is connected to the secondary input terminal of the coupling inductor 1223 or to the secondary output terminal of the coupling inductor 1223 to control the secondary output terminal to provide a second voltage signal Vout2 to the positive voltage output terminal.

[0091] In this embodiment, the first switch Q1 is used to inject input energy into the coupling inductor 1223 in the first stage, and the second switch Q2 is used to provide a freewheeling circuit for the primary coil (primary winding) in the second stage, and simultaneously reflect voltage to turn on the rectifier unit 1224.

[0092] For example, the first switch Q1 and the second switch Q2 can be two independent switches. Alternatively, the first switch Q1 and the second switch Q2 can be integrated into a single switch chip. Yet another example is that the first switch Q1 and the second switch Q2 can also be integrated with other devices, and the configuration is not limited thereto.

[0093] The aforementioned light-emitting driving circuit 122 includes a coupling inductor 1223 comprising a primary coil (primary winding) and a secondary coil (secondary winding), both wound in the same direction. Since the rectifier unit 1224 is connected to either the secondary input terminal or the secondary output terminal of the coupling inductor 1223, the second voltage signal Vout2 output from the secondary output terminal of the coupling inductor 1223 connected to the secondary coil (secondary winding) flips the voltage reference direction once. When the first switch Q1 is turned on and the second switch Q2 is turned off, the primary input terminal of the primary coil (primary winding) is connected to the initial voltage Vin, and the same-name terminal is positive. The secondary input terminal of the secondary coil (secondary winding) is also positive, but the secondary input terminal is disconnected from the initial voltage input terminal through the rectifier unit 1224, or the secondary output terminal is disconnected from the positive voltage output terminal through the rectifier unit 1224. Therefore, at this time, the first voltage signal Vout1 increases, and the second voltage signal Vout2 is not affected by the primary coil (primary winding) and there is no energy transmission. When the first switch Q1 is off and the second switch Q2 is on, the primary coil (primary winding) current freewheels, and the primary input node voltage is close to 0V, lower than the primary output node voltage. The induced voltage in the secondary coil (secondary winding) then reverses direction. The secondary input terminal is connected to the initial voltage input terminal via rectifier unit 1224, or the secondary output terminal is connected to the forward voltage output terminal via rectifier unit 1224. Energy is sent to the secondary output terminal. Therefore, during the phase when the first switch Q1 is off, the first voltage signal Vout1 has a falling edge, while the second voltage signal Vout2 has a rising edge. Since the phases of the first voltage signal Vout1 and the second voltage signal Vout2 are opposite, and the rectifier unit 1224 is located at the secondary input or secondary output of the coupling inductor 1223, the amplitudes of the first voltage signal Vout1 and the second voltage signal Vout2 are different under the impedance of the rectifier unit 1224. Therefore, even though the phases of the first voltage signal Vout1 and the second voltage signal Vout2 are opposite, the drive control circuit 123 can still obtain effective feedback information by superimposing the first voltage signal Vout1 and the second voltage signal Vout2, thereby achieving accurate control of the conduction and disconnection of the first switch Q1 and the second switch Q2.

[0094] During the backlight driving process of the display device, the light-emitting chip 121 emits light of the target brightness under the combined action of forward voltage and driving current. The forward voltage of the light-emitting chip 121 is determined by the semiconductor bandgap, which determines the minimum conduction level of the chip and varies depending on the light-emitting material system (e.g., indium gallium nitride (InGaN) – the forward voltage for white light-emitting chip 121 is approximately 2.8V; aluminum gallium indium phosphide (AlGaInP) – the forward voltage for red light-emitting chip 121 is approximately 2.0V). With a fixed initial voltage Vin connected to the light-emitting driving circuit 122, the forward voltage determines the maximum number of light-emitting chips 121 connected in series, thus affecting the efficiency of the light-emitting driving circuit 122. The brightness of the light-emitting chip 121 is affected by the driving current; for example, the brightness of the light-emitting chip 121 can be positively correlated with the driving current. The backlight intensity provided by the backlight module 12 can be set by the driving current.

[0095] In this circuit, the first switch Q1 and the second switch Q2 are not simultaneously turned on or off. For example, in the first stage (TON stage, conduction stage), the first switch Q1 is turned on, the second switch Q2 is turned off, and the initial voltage Vin is applied to the primary input terminal of the coupling inductor 1223. The current iL1 flowing through the primary coil (primary winding) of the coupling inductor 1223 increases linearly, and energy is stored in the coupling inductor 1223 in the form of magnetization. Because the rectifier unit 1224 is cut off, the current iL2 flowing through the secondary coil (secondary winding) of the coupling inductor is 0. At this time, the second voltage signal Vout2 output from the secondary output terminal provides a positive voltage to the light-emitting chip 121.

[0096] In the second stage (TOFF stage, disconnection stage), the first switch Q1 is turned off, the second switch Q2 is turned on, the voltage across the primary coil (primary winding) is reversed, and the first voltage signal Vout1 is applied in reverse to the primary coil (primary winding), causing iL1 to decrease. The induced voltage in the secondary coil (secondary winding) of the coupled inductor is reversed, and the rectifier unit 1224 is turned on. At this time, the current iL2 through the secondary coil (secondary winding) of the coupled inductor increases, and the second voltage signal Vout2 output from the secondary output provides a positive voltage to the light-emitting chip 121. Since the secondary input is connected to the initial voltage input, the relationship between the second voltage signal Vout2 output from the secondary output and the initial voltage Vin can be expressed as: Vout2≈Vin+D*Vin / N, where Vin is the initial voltage Vin, D is the duty cycle (the proportion of the conduction time of the first switch Q1 in the entire switching cycle), and N is the ratio of the number of turns of the primary coil to the number of turns of the secondary coil (secondary winding).

[0097] The light-emitting driving circuit 122 includes a first switch Q1, a second switch Q2, a coupling inductor 1223, and a rectifier unit 1224. The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND. The coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit 122, and the primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1. The rectifier unit 1224 is connected to the secondary input terminal of the coupling inductor 1223, or to the secondary output terminal of the coupling inductor 1223, to control the secondary output terminal to provide a second voltage signal Vout2 to the positive voltage output terminal. Therefore, the light-emitting driving circuit 122 in this embodiment can function as a Flybuck (isolated step-down) circuit. The light-emitting driving circuit 122 achieves isolation through the coupling inductor 1223. Only magnetic coupling exists between the primary coil and the secondary coil, with no direct electrical connection, thus forming physical isolation. The secondary coil (secondary winding) reference ground can be set independently. Energy is transferred through the magnetic field during the switching cycle, automatically tracking the output voltage of the primary coil (primary winding) without optocoupler feedback, achieving electrical isolation and voltage regulation.

[0098] The backlight module 12 in this embodiment may include a drive control circuit 123. The drive control circuit 123 is connected to the controlled terminal of the first switch Q1, the controlled terminal of the second switch Q2, the primary output terminal and the positive voltage output terminal of the coupling inductor 1223, respectively. The drive control circuit 123 is configured to control the first switch Q1 to turn on or off, and the second switch Q2 to turn on or off, according to the first voltage signal Vout1 and the second voltage signal Vout2, so as to adjust the second voltage signal Vout2.

[0099] For example, the drive control circuit 123 may include a controller and a feedback circuit. The feedback circuit is connected to the positive voltage output terminal and the primary output terminal, and is used to receive the first voltage signal Vout1 and the second voltage signal Vout2, and to fuse the first voltage signal Vout1 and the second voltage signal Vout2 to generate a corresponding feedback voltage signal. The controller is connected to the feedback circuit, the controlled terminal of the first switch Q1, and the controlled terminal of the second switch Q2, and controls the conduction and turn-off of the first switch Q1 and the second switch Q2 according to the feedback voltage signal.

[0100] For example, the drive control circuit 123 can superimpose the first voltage signal Vout1 and the second voltage signal Vout2 to generate a feedback voltage signal. In COT mode, the conduction time of the first switch Q1 changes linearly with the voltage change of the feedback voltage signal. When the ripple of the feedback voltage signal drops to a preset threshold, the drive control circuit 123 outputs a control signal of the response level to the controlled terminal of the first switch Q1, thereby driving the first switch Q1 to conduct for a fixed time T. ON Turn on, and simultaneously control the second switch Q2 for a fixed time T. ON Disconnect, then disconnect the first switch Q1 and turn on the second switch Q2.

[0101] In this embodiment, the light-emitting driving circuit 122 includes a first switch Q1, a second switch Q2, a coupling inductor 1223, and a rectifier unit 1224. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, and the secondary input terminal of the coupling inductor 1223 is directly connected to the initial voltage input terminal or connected to the initial voltage input terminal through the rectifier unit 1224. Therefore, when the light-emitting driving circuit 122 provides the second voltage signal Vout2, it can superimpose the initial voltage Vin and the isolation voltage generated by the coupling inductor 1223 itself, thereby achieving a boost effect where the second voltage signal Vout2 is greater than the initial voltage Vin, and improving the conversion efficiency of the light-emitting driving circuit 122. On the other hand, the drive control circuit 123 is connected to the controlled terminal of the first switch Q1, the controlled terminal of the second switch Q2, the primary output terminal and the positive voltage output terminal of the coupling inductor 1223, respectively. The drive control circuit 123 is configured to control the conduction or cutoff of the first switch Q1 and the second switch Q2 according to the first voltage signal Vout1 and the second voltage signal Vout2, so as to adjust the second voltage signal Vout2. This can overcome the limitation that the second voltage signal Vout2 and the first voltage signal Vout1 are out of phase and cannot participate in the COT mode. Under the combined action of the first voltage signal Vout1 and the second voltage signal Vout2, the drive control circuit 123 controls the conduction or cutoff of the first switch Q1 and the second switch Q2, so that the second voltage signal Vout2 can meet the positive voltage requirement of the light-emitting chip 121 and improve the stability of the backlight drive.

[0102] In some embodiments, the drive control circuit 123 is configured to control the first switch Q1 to turn on or off, and the second switch Q2 to turn on or off, based on the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2.

[0103] In this embodiment, the high-frequency component of the first voltage signal Vout1 is the ripple generated during the switching of the first switch Q1 and the second switch Q2. Its frequency is close to the switching frequency, which can reflect the dynamic changes in the output voltage of the light-emitting driving circuit 122. The energy transfer of the light-emitting driving circuit 122 in this embodiment depends on the switching cycles of the first switch Q1 and the second switch Q2. The voltage changes of the first voltage signal Vout1 and the second voltage signal Vout2 also occur during the switching cycles of the first switch Q1 and the second switch Q2. Since the phase of the second voltage signal Vout2 is opposite to the phase of the first voltage signal Vout1, the high-frequency component of the first voltage signal Vout1 can more quickly and accurately reflect the voltage changes of the first voltage signal Vout1 and the second voltage signal Vout2. The key to the feedback control of the drive control circuit 123 on the light-emitting drive circuit 122 lies in accurately capturing the real-time voltage fluctuations during the switching cycles of the first switch Q1 and the second switch Q2, thereby quickly correcting the imbalance of the coupling inductor 1223 in the energy transfer process. Therefore, the drive control circuit 123 controls the conduction or cutoff of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2, which can improve the timeliness and accuracy of the drive control circuit 123 in adjusting the second voltage signal Vout2.

[0104] In some embodiments, see Appendix Figure 4 , attached Figure 4 This diagram illustrates one of the structural schematics of a drive control circuit 123 according to an embodiment of this application. The drive control circuit 123 in this embodiment includes a first filter unit 1231 and a drive controller 1232.

[0105] The first filtering unit 1231 is connected to the primary output terminal. The first filtering unit 1231 is configured to filter out the low-frequency component of the first voltage signal Vout1 and provide the high-frequency component of the first voltage signal Vout1.

[0106] The drive controller 1232 is connected to the first filter unit 1231, the controlled terminal of the first switch Q1, the controlled terminal of the second switch Q2, and the positive voltage output terminal. It controls the first switch Q1 to turn on or off and the second switch Q2 to turn on or off according to the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2, and adjusts the second voltage signal Vout2.

[0107] For example, the first filtering unit 1231 can be a capacitor. The AC impedance of the capacitor is not a fixed value, but is inversely proportional to the signal frequency. Therefore, the capacitor has different impedances for signals of different frequencies: it presents high impedance to low-frequency components, hindering their passage, and presents low impedance to high-frequency components, allowing them to pass. The capacitor can be connected to both the primary output terminal and the drive controller 1232. The low-frequency component of the first voltage signal Vout1 is filtered out by the capacitor, thereby enabling the drive controller 1232 to receive the high-frequency component of the first voltage signal Vout1.

[0108] In this embodiment, the first filtering unit 1231 is connected to the primary output terminal, and the drive controller 1232 is connected to the first filtering unit 1231, the controlled terminal of the first switch Q1, the controlled terminal of the second switch Q2, and the positive voltage output terminal. The first filtering unit 1231 can filter out the low-frequency component of the first voltage signal Vout1, thereby providing the high-frequency component of the first voltage signal Vout1 to the drive controller 1232. This allows the drive controller 1232 to receive the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2 output from the positive voltage output terminal. Based on the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2, the drive controller 1232 controls the conduction or cutoff of the first switch Q1 and the second switch Q2, thereby improving the sensitivity of the drive control circuit 123 in adjusting the second voltage signal Vout2.

[0109] In some embodiments, see Appendix Figure 5 , attached Figure 5 The second schematic diagram of the drive control circuit 123 in the embodiment of this application is shown. The drive control circuit 123 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected to the positive voltage output terminal; the first end of the second resistor R2 is connected to the second end of the first resistor R1, and the second end of the second resistor R2 is connected to the equivalent ground terminal GND.

[0110] The first resistor R1 and the second resistor R2 are configured to perform voltage division processing on the second voltage signal Vout2, and provide the low-frequency component of the second voltage signal Vout2 to the drive controller 1232.

[0111] The first resistor R1 and the second resistor R2 divide the second voltage signal Vout2, which reduces the amplitude of the second voltage signal Vout2. The drive controller 1232 controls the first switch Q1 and the second switch Q2 to turn on or off based on the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2. When adjusting the second voltage signal Vout2, since the first voltage signal Vout1 and the second voltage signal Vout2 are out of phase, the amplitude of the second voltage signal Vout2 is reduced, which helps to increase the amplitude of the final feedback voltage signal and provide more effective feedback information. This meets the requirements of the drive controller 1232 for feedback signals in COT mode.

[0112] The drive controller 1232 is configured to control the first switch Q1 to turn on or off, and the second switch Q2 to turn on or off, based on the high-frequency component of the first voltage signal Vout1 and the second voltage signal Vout2. Adjusting the second voltage signal Vout2 includes: the drive controller 1232 is configured to control the first switch Q1 to turn on or off, and the second switch Q2 to turn on or off, based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2.

[0113] The second voltage signal Vout2 is the effective voltage signal that actually provides a positive voltage to the light-emitting chip. The first switch Q1 and the second switch Q2 are turned on or off based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2. When adjusting the second voltage signal Vout2, the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2 are superimposed to generate a feedback voltage signal. The drive controller 1232 compares the superimposed feedback voltage signal with a preset threshold. This not only effectively reflects the voltage change of the second voltage signal Vout2, but also ensures that the high-frequency component of the first voltage signal Vout meets the phase requirement of the feedback signal for the drive controller 1232 in COT mode. The drive controller 1232 can adjust the second voltage signal Vout2 more accurately, and the adjusted second voltage signal Vout2 better matches the positive voltage requirement of the light-emitting chip 121.

[0114] In this embodiment, when the light-emitting driving circuit 122 is operating, with the first switch Q1 turned on and the second switch Q2 turned off, the primary coil (primary winding) does not transfer energy to the secondary coil (secondary winding). When the first switch Q1 is turned off and the second switch Q2 is turned on, the primary coil (primary winding) transfers energy to the secondary coil (secondary winding). The primary and secondary coils share a common magnetic core, and the second voltage signal Vout2 is affected by the first voltage signal Vout1 and the number of turns in the primary coil (primary winding). When the first voltage signal Vout1 is stable, the voltage of the second voltage signal Vout2 will automatically stabilize through magnetic flux. Therefore, the primary output terminal can be defined as the master output, and the secondary output terminal can be defined as the slave output. By controlling the conduction time of the first switch Q1 and the second switch Q2 through the high-frequency component of the first voltage signal Vout1, stable control of the second voltage signal Vout2 can be achieved. The second voltage signal Vout2 is determined by the magnetic coupling characteristics of the coupling inductor 1223. It does not directly participate in the control of the conduction time of the first switch Q1 and the second switch Q2, but the second voltage signal Vout2 can characterize the following trend of the second voltage signal Vout2 and reflect the following deviation caused by coupling interference.

[0115] In this embodiment, the first voltage signal Vout1 includes effective feedback information (effective ripple synchronized with the switching cycles of the first switch Q1 and the second switch Q2), but also contains invalid noise. Therefore, extracting the high-frequency component of the first voltage signal Vout1 can accurately obtain effective feedback information and accurately capture the dynamic changes of the first voltage signal Vout1 and the second voltage signal Vout2, thereby improving the dynamic response speed of the drive control circuit 123. The second voltage signal Vout2, as the voltage signal output from the output terminal of the light-emitting drive circuit 122, participates in the adjustment of the second voltage signal Vout2 as part of the feedback signal. The function of the second voltage signal Vout2 is to stably follow the static voltage level of the first voltage signal Vout1, rather than to capture its dynamic changes. The voltage of the second voltage signal Vout2 is determined by magnetic coupling. If high-frequency feedback is provided to it, it will amplify the fluctuations caused by coupling differences, which is not conducive to the sensitive adjustment of the drive control circuit 123. Therefore, providing the low-frequency component of the second voltage signal Vout2 to the drive controller 1232 can suppress the low-frequency drift of the secondary output terminal (from the output) and ensure static stability. This allows the drive control circuit 123 to control the on / off state of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2. This not only improves the sensitivity of the drive control circuit 123 in regulating the second voltage signal Vout2, but also corrects the low-frequency drift caused by the increased core loss of the coupling inductor 1223 and the slow waveguide of the initial voltage Vin through the low-frequency component of the second voltage signal Vout2, thus ensuring the voltage stability of the second voltage signal Vout2.

[0116] In some embodiments, see Appendix Figure 6 , attached Figure 6 The third schematic diagram of the drive control circuit 123 in this embodiment is shown. The drive control circuit 123 in this embodiment also includes a third resistor R3 and a first capacitor C1. The first end of the third resistor R3 is connected to the first end of the second resistor R2, and the second end of the third resistor R3 is connected to the drive controller 1232; the first capacitor C1 is connected to the second end of the third resistor R3 and the equivalent ground terminal GND.

[0117] In this embodiment, the output impedance of the voltage divider network formed by the first resistor R1 and the second resistor R2 is reduced. Since the feedback terminal connected to the second and first ends of the first and second impedances of the drive controller 1232 is typically a high-impedance input, this embodiment connects a third resistor R3 between the second and first ends of the first and second impedances and the drive controller 1232. This avoids impedance mismatch problems caused by direct connection between the drive controller 1232 and the second and first ends of the first and second impedances. If the voltage divider node connecting the second end of the first resistor R1 and the first end of the second resistor R2 experiences high voltage due to initial voltage Vin overshoot or component breakdown, the third resistor R3 between the second and first ends of the first and second impedances and the drive controller 1232 can limit the current flowing into the drive controller 1232, preventing damage from large currents and protecting the drive controller 1232. Furthermore, the first capacitor C1 is connected to the second terminal of the third resistor R3 and the equivalent ground terminal GND respectively. Since the capacitive reactance of the first capacitor C1 decreases as the frequency increases, the connection of the first capacitor C1 to the second terminal of the third resistor R3 and the equivalent ground terminal GND respectively can provide a low impedance path for the high-frequency noise in the second voltage signal Vout2. This allows the high-frequency noise to pass through the first capacitor C1 to the equivalent ground terminal GND, preventing the high-frequency noise from reaching the drive controller 1232. This avoids the drive controller 1232 from misjudging the voltage changes of the first voltage signal Vout1 and the second voltage signal Vout2 under the interference of the high-frequency noise in the second voltage signal Vout2, and ensures that the drive control circuit 123 accurately adjusts the second voltage signal Vout2.

[0118] In some embodiments, the drive control circuit 123 in this application may include a second filter unit 1233. The second filter unit 1233 is connected to the positive voltage output terminal and is configured to filter out the high-frequency components of the second voltage signal Vout2 and provide the low-frequency components of the second voltage signal Vout2 to the drive controller 1232.

[0119] For example, the second filter unit 1233 may have a first terminal, a second terminal and a third terminal. The first terminal of the second filter unit 1233 may be connected to the secondary input terminal of the coupling inductor 1223, the second terminal of the second filter unit 1233 may be connected to the positive voltage output terminal of the light-emitting driving circuit 122, and the third terminal of the third filter unit may be connected to the first terminal of the first resistor R1.

[0120] In another example, the second filter unit 1233 may have a first terminal, a second terminal and a third terminal. The first terminal of the second filter unit 1233 may be connected to the positive voltage output terminal of the light-emitting driving circuit 122, the second terminal of the second filter unit 1233 may be connected to the first terminal of the first resistor R1, and the third terminal of the third filter unit may be connected to the equivalent ground terminal GND.

[0121] It is understood that the connection relationship of the second filter unit 1233 can also be other than the example above, as long as it is ensured that the second filter unit 1233 can perform low-pass filtering of the second voltage signal Vout2.

[0122] In this embodiment, a second filtering unit 1233 is provided at the positive voltage output terminal of the light-emitting driving circuit 122, so that the second voltage signal Vout2 output from the positive voltage output terminal of the light-emitting driving circuit 122 can be filtered by the second filtering unit 1233, thereby filtering out the high-frequency components of the second voltage signal Vout2 and providing the low-frequency components of the second voltage signal Vout2 to the driving controller 1232. Since the first voltage signal Vout1 and the second voltage signal Vout2 are out of phase, when the driving controller 1232 performs superposition processing on the first voltage signal Vout1 and the second voltage signal Vout2, the high-frequency components of the second voltage signal Vout2 will reduce the amplitude of the superimposed signal, thereby affecting the driving controller 1232's ability to capture the dynamic changes of the first voltage signal Vout1 and the second voltage signal Vout2, and reducing the sensitivity of the driving controller 1232. In this embodiment, the high-frequency component of the second voltage signal Vout2 is filtered out by the second filtering unit 1233, so that when the drive controller 1232 processes the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, it can reduce the interference of the high-frequency component of the second voltage signal Vout2 on the high-frequency component of the first voltage signal Vout1, thereby improving the sensitivity of the drive controller 1232.

[0123] In some embodiments, see Appendix Figure 7 , attached Figure 7 This diagram illustrates one of the structural schematics of a second filter unit 1233 according to an embodiment of this application. The second filter unit 1233 in this embodiment may include a fourth resistor R4 and a second capacitor C2. The fourth resistor R4 is connected to both the positive voltage output terminal and the first terminal of the first resistor R1; the second capacitor C2 is connected to both the secondary input terminal and the first terminal of the first resistor R1.

[0124] In this embodiment, the fourth resistor R4 and the second capacitor C2 constitute a low-pass filter unit. The fourth resistor R4 is connected to the positive voltage output terminal and the first terminal of the first resistor R1, respectively. The second capacitor C2 is connected to the secondary input terminal and the first terminal of the first resistor R1, respectively. Since the second capacitor C2 has the characteristic that the capacitive reactance is inversely proportional to the signal frequency, the capacitive reactance of the second capacitor C2 is extremely large for the low-frequency component in the second voltage signal Vout2. The signal transmission line between the first terminal of the first resistor R1 and the secondary input terminal of the coupling inductor 1223 can be approximated as an open circuit. At this time, the low-frequency component in the second voltage signal Vout2 enters the drive controller 1232 through the fourth resistor R4 and the first resistor R1. For the high-frequency component in the second voltage signal Vout2, the capacitive reactance of the second capacitor C2 is extremely small. The signal transmission line between the first end of the first resistor R1 and the secondary input end of the coupling inductor 1223 can be approximated as a short circuit. The high-frequency component of the second voltage signal Vout2 is fed into the secondary input end of the coupling inductor 1223, preventing the drive controller 1232 from accessing the high-frequency component of the second voltage signal Vout2, thereby affecting the drive controller 1232's judgment of the high-frequency component of the first voltage signal Vout1 and improving the response speed and accurate adjustment of the drive controller 1232 in adjusting the second voltage signal Vout2.

[0125] In some embodiments, see appendix Figure 8 , attached Figure 8 This is a second schematic diagram of the structure of the second filter unit 1233 in one embodiment of this application. The second filter unit 1233 in this embodiment may include a fifth resistor R5 and a third capacitor C3. The fifth resistor R5 is connected to the positive voltage output terminal and the first terminal of the first resistor R1, respectively; the third capacitor C3 is connected to the first terminal of the first resistor R1 and the equivalent ground terminal GND, respectively.

[0126] In this embodiment, the fifth resistor R5 and the third capacitor C3 constitute a low-pass filter unit. The fifth resistor R5 is connected to the positive output terminal and the first terminal of the first resistor R1, respectively. The third capacitor C3 is connected to the first terminal of the first resistor R1 and the equivalent ground terminal GND, respectively. The second voltage signal Vout2 is connected to the third capacitor C3 through the fifth resistor R5. The fifth resistor R5 can limit the discharge current of the high-frequency component of the second voltage signal Vout2, preventing the high-frequency signal of the second voltage signal Vout2 from directly connecting to the equivalent ground terminal GND from the positive output terminal through the third capacitor C3, which would cause the current to be too large instantaneously, damaging the capacitor or the drive controller 1232. For the low-frequency component of the second voltage signal Vout2, since the capacitive reactance of the third capacitor C3 is inversely proportional to the signal frequency, the capacitive reactance of the third capacitor C3 is much greater than the impedance of the fifth resistor R5. The low-frequency component of the second voltage signal Vout2 enters the drive controller 1232 with almost no attenuation after passing through the fifth resistor R5, which can improve the quality of the low-frequency component of the second voltage signal Vout2 received by the drive controller 1232. For the high-frequency component of the second voltage signal Vout2, since the capacitive reactance of the third capacitor C3 is inversely proportional to the signal frequency, the capacitive reactance of the third capacitor C3 is much smaller than the impedance of the fifth resistor R5. Therefore, the voltage division ratio X between the third capacitor C3 and the fifth resistor R5 is... C3 As R5 approaches zero, the high-frequency components of the second voltage signal Vout2 are significantly attenuated. The fifth resistor R5 amplifies the voltage division ratio difference between the high-frequency and low-frequency components of the second voltage signal Vout2, improving the filtering effect of the second filter unit 1233 in removing high-frequency components and outputting low-frequency components. Furthermore, the third capacitor C3 is directly connected to the equivalent ground terminal GND, allowing the high-frequency components of the second voltage signal Vout2 to be directly connected to the equivalent ground terminal GND, reducing interference from the high-frequency components of the second voltage signal Vout2 on other signal transmission lines and improving the stability of the drive control circuit 123.

[0127] In some embodiments, see Appendix Figure 9 , attached Figure 9 This diagram illustrates one of the structural schematics of a rectifier unit 1224 according to an embodiment of this application. The rectifier unit 1224 in this embodiment may include a cutoff diode D1. The anode of the cutoff diode D1 is connected to the secondary output terminal of the coupling inductor 1223, and the cathode of the cutoff diode D1 is connected to the forward voltage output terminal and the light-emitting chip 121.

[0128] When the first switch Q1 is on and the second switch Q2 is off, the current through the primary winding of the coupling inductor 1223 increases linearly. Since the primary and secondary windings of the coupling inductor 1223 have opposite polarities, the induced voltage in the secondary winding causes the positive (cathode) voltage of the cutoff diode D1 to be lower than the negative (cathode) voltage. Therefore, the cutoff diode D1 is reverse-biased and cut off, preventing current flow. At this time, the light-emitting drive circuit 122 stops outputting the second voltage signal Vout2 to the light-emitting chip 121. When the first switch Q1 is off and the second switch Q2 is on, since the current in the primary winding of the coupling inductor 1223 does not change abruptly, a freewheeling circuit is formed in the primary winding of the coupling inductor 1223 under the action of the second switch Q2. At this time, the induced voltage in the secondary coil (secondary winding) of the coupling inductor 1223 causes the voltage at the positive (cathode) terminal of the cutoff diode D1 to be higher than the voltage at the negative (cathode) terminal, thus switching the cutoff diode D1 to a forward bias state and turning it on. Based on this, the energy stored in the coupling inductor 1223 can be superimposed on the initial voltage Vin connected to the secondary input terminal, providing a second voltage signal Vout2 to the light-emitting chip 121 through the negative terminal of the cutoff diode D1, thereby achieving high-efficiency power supply.

[0129] Alternatively, in some embodiments, see Appendix Figure 10 , attached Figure 10 This is a second schematic diagram of the structure of a rectifier unit 1224 according to an embodiment of this application. The rectifier unit 1224 may include a rectifier switch and a rectifier controller 2241. The first terminal of the rectifier switch Q3 is connected to the initial voltage input terminal, and the second terminal of the rectifier switch Q3 is connected to the secondary input terminal of the coupling inductor 1223. The rectifier controller 2241 is connected to the first terminal, the second terminal, and the controlled terminal of the rectifier switch Q3, respectively. The rectifier controller 2241 is configured to control the rectifier switch Q3 to conduct the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupling inductor 1223 when the primary coil of the coupling inductor 1223 is discharging, and to control the rectifier switch Q3 to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupling inductor 1223 when the primary coil of the coupling inductor 1223 is charging.

[0130] For example, the rectifier controller 2241 can be powered by the power supply module of the display device to ensure normal operation.

[0131] The primary coil (primary winding) of the coupling inductor 1223 is in a discharging state, which can be understood as the current through the primary coil (primary winding) being unable to maintain its original magnitude (the current of the coupling inductor 1223 cannot change abruptly), and the magnetic flux in the core of the coupling inductor 1223 rapidly decreases, resulting in a weakened magnetic field.

[0132] The primary coil (primary winding) of the coupling inductor 1223 is in a charging state, which can be understood as the current through the primary coil (primary winding) increasing, the magnetic flux of the magnetic core of the coupling inductor 1223 increasing, and the magnetic field strengthening.

[0133] In this embodiment, the rectifier controller 2241 is connected to the first terminal, the second terminal and the controlled terminal of the rectifier switch Q3, respectively, and can sample the voltage and / or current of the first terminal and the second terminal of the rectifier switch Q3 to realize the monitoring of the working status of the rectifier switch Q3 and overcurrent protection.

[0134] For example, the first terminal of the rectifier switch Q3 can be the source. The rectifier controller 2241 can sample the source current of the rectifier switch Q3 to protect it. In cases of abnormal increases in the initial voltage Vin of the light-emitting driver circuit 122 or short circuits in the light-emitting chip 121, the source current of the rectifier switch Q3 may increase sharply. If this exceeds the rated current of the rectifier switch Q3, it may overheat and be damaged due to excessive conduction losses. The rectifier controller 2241 samples the source current of the rectifier switch Q3. If the source current exceeds a preset current threshold, it controls the rectifier switch Q3 to be turned off, thereby protecting it.

[0135] The second terminal of the rectifier switch Q3 can be the drain. In the light-emitting driving circuit 122 of this application embodiment, at the instant the rectifier switch Q3 is turned off, due to problems such as leakage inductance and parasitic capacitance of the coupling inductor 1223, a voltage spike may be generated at the drain of the rectifier switch Q3. If the spike exceeds the withstand voltage of the rectifier switch Q3, it may break down the insulation layer between the source and the drain, leading to the damage of the rectifier switch Q3. Therefore, the rectifier controller 2241 can sample the drain voltage and current of the rectifier switch Q3 to monitor the operating state of the rectifier switch Q3 and protect the rectifier switch Q3. For example, when the drain voltage is close to 0 but the drain current is extremely large, the rectifier controller 2241 can trigger overcurrent protection, turn off the rectifier switch Q3, and / or trigger an alarm. When the drain voltage is close to the initial voltage Vin, but the drain current is close to 0, the rectifier controller 2241 can trigger open circuit protection, turn off the rectifier switch Q3, and / or trigger an alarm.

[0136] The controlled terminal of the rectifier switch Q3 can be the gate. The rectifier controller 2241 can control the rectifier switch Q3 to turn on or off by outputting a control signal of the corresponding level to the rectifier switch Q3.

[0137] In this embodiment, the first terminal of the rectifier switch Q3 is connected to the initial voltage input terminal, and the second terminal of the rectifier switch Q3 is connected to the secondary input terminal of the coupling inductor 1223. The rectifier controller 2241 is connected to the first terminal, the second terminal, and the controlled terminal of the rectifier switch Q3. The rectifier controller 2241 is configured to control the rectifier switch Q3 to conduct the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupling inductor 1223 when the primary coil of the coupling inductor 1223 is discharged. This ensures that when the first switch Q1 is off and the second switch Q2 is on, the secondary input terminal of the coupling inductor 1223 is connected to the initial voltage Vin. Under the action of the change in magnetic flux caused by the increase in the current of the primary coil (primary winding) of the coupling inductor 1223, an isolation voltage is induced, achieving voltage superposition. This makes the second voltage signal Vout2 provided by the positive voltage output terminal the sum of the initial voltage Vin and the induced isolation voltage.

[0138] When the primary coil of the coupling inductor 1223 is charging, the rectifier switch Q3 is controlled to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupling inductor 1223. This ensures that when the first switch Q1 is turned on and the second switch Q2 is turned off, the primary coil (primary winding) of the coupling inductor 1223 converts the electrical energy corresponding to the initial voltage Vin into the magnetic field energy of the coupling inductor 1223 core. During this stage, the first switch Q1 is turned on to establish the primary current of the primary coil (primary winding), allowing the core to accumulate sufficient magnetic field energy. This provides a preparatory step for the subsequent energy release of the secondary coil (secondary winding), preventing the rectifier switch Q3 from disrupting the energy storage process of the core, causing energy induction failure or energy waste. This achieves efficient storage of magnetic field energy and stable output of the second voltage signal Vout2.

[0139] In some embodiments, see Appendix Figure 11 , attached Figure 11 A second schematic diagram of the light-emitting driving circuit 122 in an embodiment of this application is shown. The light-emitting driving circuit 122 in this embodiment may further include a fourth capacitor C4 and a fifth capacitor C5. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground terminal GND; the first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground terminal GND.

[0140] In this embodiment, the outputs of the first voltage signal Vout1 and the second voltage signal Vout2 of the light-emitting driving circuit 122 depend on the periodic energy storage and release of the coupling inductor 1223. When the first switch Q1 is turned on and the second switch Q2 is turned off, the primary coil (primary winding) of the coupling inductor 1223 stores energy through the magnetic core, and the secondary coil (secondary winding) does not generate induced energy. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground terminal GND. The first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground terminal GND, which can provide energy for the outputs of the first voltage signal Vout1 and the second voltage signal Vout2. When the first switch Q1 is off and the second switch Q2 is on, the coupling inductor 1223 releases energy. The first voltage signal Vout1 and the second voltage signal Vout2 provide output energy through the coupling inductor 1223, the fourth capacitor C4, and the fifth capacitor C5. Therefore, in this embodiment, the fourth capacitor C4 connects the primary output terminal and the equivalent ground terminal GND, and the fifth capacitor C5 connects the secondary output terminal and the equivalent ground terminal GND. This can compensate for the defects of periodic ripple (frequency consistent with the switching frequency) in the first voltage signal Vout1 and the second voltage signal Vout2 caused by the intermittent energy transfer of the light-emitting driving circuit 122, and the voltage drop / overshoot that occurs when the light-emitting chip 121 changes abruptly, thereby improving the stability of the light-emitting driving circuit 122.

[0141] In some embodiments, see Appendix Figure 12 , attached Figure 12 This is shown as a third schematic diagram of the backlight module 12 in an embodiment of this application. The backlight module 12 in this embodiment may include a light-emitting chip 121, a light-emitting driving circuit, and a driving control circuit. The light-emitting driving circuit may include a first switch Q1, a second switch Q2, a coupling inductor 1223, a cutoff diode D1, a fourth capacitor C4, and a fifth capacitor C5. The driving control circuit may include a filter capacitor C6, a first resistor R1, a second resistor R2, a fourth resistor R4, a second capacitor C2, and a driving controller 1232.

[0142] The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND; the coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit, and the primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1. The positive terminal of the cutoff diode D1 is connected to the secondary output terminal of the coupling inductor 1223, and the negative terminal of the cutoff diode D1 is connected to the light-emitting chip 121. Filter capacitor C6 is connected to both the primary output terminal and the drive controller 1232. Filter capacitor C6 is configured to filter out the low-frequency component of the first voltage signal Vout1 and provide the high-frequency component of the first voltage signal Vout1 to the drive controller 1232. The first terminal of the first resistor R1 is connected to the positive voltage output terminal; the first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1, and the equivalent ground terminal GND of the second terminal of the second resistor R2 is connected. The fourth resistor R4 is connected to both the positive voltage output terminal and the first terminal of the first resistor R1; the second capacitor C2 is connected to both the secondary input terminal and the first terminal of the first resistor R1. The drive controller 1232 is configured to control the on / off state of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground terminal GND; the first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground terminal GND.

[0143] In some embodiments, see Appendix Figure 13 , attached Figure 13 This is shown as the fourth schematic diagram of the backlight module 12 in this embodiment. The backlight module 12 in this embodiment may include a light-emitting chip 121, a light-emitting driving circuit, and a driving control circuit. The light-emitting driving circuit may include a first switch Q1, a second switch Q2, a coupling inductor 1223, a cutoff diode D1, a fourth capacitor C4, and a fifth capacitor C5. The driving control circuit may include a filter capacitor C6, a first resistor R1, a second resistor R2, a fifth resistor R5, a third capacitor C3, and a driving controller 1232.

[0144] The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND; the coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit, and the primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1. The positive terminal of the cutoff diode D1 is connected to the secondary output terminal of the coupling inductor 1223, and the negative terminal of the cutoff diode D1 is connected to the light-emitting chip 121. Filter capacitor C6 is connected to both the primary output terminal and the drive controller 1232. Filter capacitor C6 is configured to filter out the low-frequency component of the first voltage signal Vout1 and provide the high-frequency component of the first voltage signal Vout1 to the drive controller 1232. The first terminal of the first resistor R1 is connected to the positive voltage output terminal; the first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1, and the equivalent ground terminal GND of the second terminal of the second resistor R2 is connected. The fifth resistor R5 is connected to both the positive voltage output terminal and the first terminal of the first resistor R1; the third capacitor C3 is connected to both the first terminal of the first resistor R1 and the equivalent ground terminal GND. The drive controller 1232 is configured to control the on / off state of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground terminal GND; the first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground terminal GND.

[0145] In some embodiments, see Appendix Figure 14 , attached Figure 14 Fifth schematic diagram of the backlight module 12 in this embodiment is shown. The backlight module 12 in this embodiment may include a light-emitting chip 121, a light-emitting driving circuit, and a driving control circuit. The light-emitting driving circuit may include a first switch Q1, a second switch Q2, a coupling inductor 1223, a rectifier switch Q3 and a rectifier controller, a fourth capacitor C4, and a fifth capacitor C5. The driving control circuit may include a filter capacitor C6, a first resistor R1, a second resistor R2, a fourth resistor R4, a second capacitor C2, and a driving controller 1232.

[0146] The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND; the coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit, and the primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1. The first terminal of rectifier switch Q3 is connected to the initial voltage input terminal, and the second terminal of rectifier switch Q3 is connected to the secondary input terminal of coupling inductor 1223. A rectifier controller is connected to the first terminal, the second terminal, and the controlled terminal of rectifier switch Q3. The rectifier controller is configured to control rectifier switch Q3 to conduct the voltage transmission line between the initial voltage input terminal and the secondary input terminal of coupling inductor 1223 when the primary coil of coupling inductor 1223 is discharging, and to control rectifier switch Q3 to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of coupling inductor 1223 when the primary coil of coupling inductor 1223 is charging. A filter capacitor C6 is connected to the primary output terminal and the drive controller 1232. The filter capacitor C6 is configured to filter out the low-frequency component of the first voltage signal Vout1 and provide the high-frequency component of the first voltage signal Vout1 to the drive controller 1232. The first terminal of the first resistor R1 is connected to the positive voltage output terminal; the first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1, and the second terminal of the second resistor R2 is connected to the equivalent ground GND. The fourth resistor R4 is connected to both the positive voltage output terminal and the first terminal of the first resistor R1; the second capacitor C2 is connected to both the secondary input terminal and the first terminal of the first resistor R1. The drive controller 1232 is configured to control the on / off state of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground GND; the first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground GND.

[0147] In some embodiments, see Appendix Figure 15 , attached Figure 15This is shown as the sixth schematic diagram of the backlight module 12 in this embodiment. The backlight module 12 in this embodiment may include a light-emitting chip 121, a light-emitting driving circuit, and a driving control circuit. The light-emitting driving circuit may include a first switch Q1, a second switch Q2, a coupling inductor 1223, a rectifier switch Q3 and a rectifier controller, a fourth capacitor C4, and a fifth capacitor C5. The driving control circuit may include a filter capacitor C6, a first resistor R1, a second resistor R2, a fourth resistor R4, a second capacitor C2, and a driving controller 1232.

[0148] The first terminal of the first switch Q1 is connected to the initial voltage input terminal; the first terminal of the second switch Q2 is connected to the second terminal of the first switch Q1, and the second terminal of the second switch Q2 is connected to the equivalent ground terminal GND; the coupling inductor 1223 is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor 1223 is connected to the initial voltage input terminal, the second terminal of the first switch Q1, and the first terminal of the second switch Q2, respectively. The secondary output terminal of the coupling inductor 1223 is connected to the positive voltage output terminal of the light-emitting driving circuit, and the primary output terminal of the coupling inductor 1223 is configured to output a first voltage signal Vout1. The first terminal of rectifier switch Q3 is connected to the initial voltage input terminal, and the second terminal of rectifier switch Q3 is connected to the secondary input terminal of coupling inductor 1223. A rectifier controller is connected to the first terminal, the second terminal, and the controlled terminal of rectifier switch Q3. The rectifier controller is configured to control rectifier switch Q3 to conduct the voltage transmission line between the initial voltage input terminal and the secondary input terminal of coupling inductor 1223 when the primary coil of coupling inductor 1223 is discharging, and to control rectifier switch Q3 to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of coupling inductor 1223 when the primary coil of coupling inductor 1223 is charging. A filter capacitor C6 is connected to the primary output terminal and the drive controller 1232. The filter capacitor C6 is configured to filter out the low-frequency component of the first voltage signal Vout1 and provide the high-frequency component of the first voltage signal Vout1 to the drive controller 1232. The first terminal of the first resistor R1 is connected to the positive voltage output terminal; the first terminal of the second resistor R2 is connected to the second terminal of the first resistor R1, and the second terminal of the second resistor R2 is connected to the equivalent ground GND. The fifth resistor R5 is connected to both the positive voltage output terminal and the first terminal of the first resistor R1; the third capacitor C3 is connected to both the first terminal of the first resistor R1 and the equivalent ground GND. The drive controller 1232 is configured to control the on / off state of the first switch Q1 and the second switch Q2 based on the high-frequency component of the first voltage signal Vout1 and the low-frequency component of the second voltage signal Vout2, thereby adjusting the second voltage signal Vout2. The first terminal of the fourth capacitor C4 is connected to the primary output terminal, and the second terminal of the fourth capacitor C4 is connected to the equivalent ground GND; the first terminal of the fifth capacitor C5 is connected to the positive voltage output terminal, and the second terminal of the fifth capacitor C5 is connected to the equivalent ground GND.

[0149] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0150] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A display device, characterized in that, include: The display panel is configured to display images; A backlight module is disposed on the light-incident side of the display panel, and the backlight module is configured to provide backlight; The backlight module includes: LED chip; A light-emitting driving circuit is configured with an initial voltage input terminal and a positive voltage output terminal. The initial voltage input terminal is used to receive an initial voltage; the positive voltage output terminal is connected to the light-emitting chip to provide the light-emitting chip with a second voltage signal greater than the initial voltage. The light-emitting driving circuit includes: A first switching transistor, wherein the first terminal of the first switching transistor is connected to the initial voltage input terminal; The second switch has a first end connected to the second end of the first switch, and the second end of the second switch is connected to the equivalent ground terminal. A coupling inductor is configured with a primary input terminal, a secondary input terminal, a primary output terminal, and a secondary output terminal. The primary input terminal of the coupling inductor is connected to the initial voltage input terminal, the second terminal of the first switch, and the first terminal of the second switch, respectively. The secondary output terminal of the coupling inductor is connected to the positive voltage output terminal of the light-emitting driving circuit. The primary output terminal of the coupling inductor is configured to output a first voltage signal. A rectifier unit is connected to the secondary input terminal of the coupled inductor or to the secondary output terminal of the coupled inductor to control the secondary output terminal to provide a second voltage signal to the positive voltage output terminal; The drive control circuit is connected to the controlled terminal of the first switch, the controlled terminal of the second switch, the primary output terminal of the coupling inductor, and the positive voltage output terminal, respectively. The drive control circuit is configured to control the first switch to turn on or off, and the second switch to turn on or off, according to the first voltage signal and the second voltage signal, so as to adjust the second voltage signal.

2. The display device according to claim 1, characterized in that, The drive control circuit is configured to control the first switch to turn on or off, and the second switch to turn on or off, based on the high-frequency component of the first voltage signal and the second voltage signal, thereby adjusting the second voltage signal.

3. The display device according to claim 2, characterized in that, The drive control circuit includes: A first filtering unit is connected to the primary output terminal. The first filtering unit is configured to filter out the low-frequency component of the first voltage signal and provide the high-frequency component of the first voltage signal. The drive controller is connected to the first filter unit, the controlled terminal of the first switch, the controlled terminal of the second switch, and the positive voltage output terminal. It controls the first switch to turn on or off, and the second switch to turn on or off, based on the high-frequency component of the first voltage signal and the second voltage signal, and adjusts the second voltage signal.

4. The display device according to claim 3, characterized in that, The drive control circuit includes: A first resistor, the first end of which is connected to the positive voltage output terminal; The second resistor has its first end connected to the second end of the first resistor, and the second end of the second resistor is equivalently connected to the first end. The first resistor and the second resistor are configured to perform voltage division processing on the second voltage signal to provide the low-frequency component of the second voltage signal to the drive controller; The drive controller is configured to control the turning on or off of the first switch and the second switch based on the high-frequency component of the first voltage signal and the second voltage signal, wherein adjusting the second voltage signal includes: The drive controller is configured to control the on / off state of the first switch and the second switch based on the high-frequency component of the first voltage signal and the low-frequency component of the second voltage signal, thereby adjusting the second voltage signal.

5. The display device according to claim 4, characterized in that, The drive control circuit also includes: A third resistor, wherein the first end of the third resistor is connected to the first end of the second resistor, and the second end of the third resistor is connected to the drive controller; The first capacitor is connected to the second terminal and the equivalent ground terminal of the third resistor, respectively.

6. The display device according to claim 4, characterized in that, The drive control circuit includes: The second filtering unit is connected to the positive voltage output terminal. The second filtering unit is configured to filter out the high-frequency components of the second voltage signal and provide the low-frequency components of the second voltage signal to the drive controller.

7. The display device according to claim 6, characterized in that, The second filtering unit includes: The fourth resistor is connected to the positive voltage output terminal and the first terminal of the first resistor, respectively. The second capacitor is connected to the secondary input terminal and the first terminal of the first resistor, respectively.

8. The display device according to claim 6, characterized in that, The second filtering unit includes: The fifth resistor is connected to the positive voltage output terminal and the first terminal of the first resistor, respectively. The third capacitor is connected to the first terminal and the equivalent ground terminal of the first resistor, respectively.

9. The display device according to claim 1, characterized in that, The rectifier unit includes: A cutoff diode, wherein the anode of the cutoff diode is connected to the secondary output terminal of the coupling inductor, and the cathode of the cutoff diode is connected to the forward voltage output terminal and the light-emitting chip; Alternatively, the rectifier unit may include: A rectifier switch, wherein the first terminal of the rectifier switch is connected to the initial voltage input terminal, and the second terminal of the rectifier switch is connected to the secondary input terminal of the coupling inductor; A rectifier controller is connected to the first terminal, the second terminal, and the controlled terminal of the rectifier switch, respectively. The rectifier controller is configured to control the rectifier switch to turn on the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor when the primary coil of the coupled inductor is discharging, and to control the rectifier switch to disconnect the voltage transmission line between the initial voltage input terminal and the secondary input terminal of the coupled inductor when the primary coil of the coupled inductor is charging.

10. The display device according to claim 1, characterized in that, The light-emitting driving circuit also includes: A fourth capacitor, wherein the first terminal of the fourth capacitor is connected to the primary output terminal, and the second terminal of the fourth capacitor is connected to the equivalent ground terminal; The fifth capacitor has its first terminal connected to the positive voltage output terminal and its second terminal connected to the equivalent ground terminal.

Images