Power supply method and power supply circuit for display equipment

Abstract

The invention provides a power supply method and a power supply circuit of a display device, which are applied to a power supply architecture, the power supply architecture further comprises a power supply battery and the display device, the display device comprises an OLED screen, the power supply circuit comprises a buck-boost converter, the power supply battery is connected with the power supply circuit, and the power supply circuit is connected with the display device. And the occurrence probability of water ripples is reduced. Wherein the power supply battery is used for transmitting input voltage to the buck-boost converter; the buck-boost converter is used for switching a current mode into a first mode or a second mode according to a magnitude relationship between the input voltage and a voltage threshold value so as to output a target power supply voltage; and supplying power to an OLED screen in the display device through the target power supply voltage, wherein after the current mode is switched from the first mode to the second mode, the switching duration of switching the current mode from the second mode to the first mode is higher than a duration threshold value, and the duration threshold value is determined based on the refresh rate of the display device.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a power supply method and a power supply circuit for a display device. Background Art

[0002] For an organic light emitting diode (OLED) screen, multiple different power supply voltages are required to power it in order to work properly. Generally, a driver chip IC is required to output multiple port voltages to power the OLED screen by inputting a battery voltage. Among them, the output voltage includes a constant positive voltage ELVDD (4.6V), which is used to provide a positive voltage for the light emitting diode to the screen module. The battery voltage generally varies from 3.4V to 4.5V. Currently, a 4.6V ELVDD voltage can be obtained through a boost converter.

[0003] However, the above method may cause voltage ripples, which may cause water ripples to appear on the screen, resulting in a poor user experience. Summary of the invention

[0004] The present application provides a power supply method and a power supply circuit for a display device, which reduce the probability of water ripples occurring.

[0005] In a first aspect, a power supply circuit for a display device is provided, which is applied to a power supply architecture, wherein the power supply architecture also includes a power supply battery and a display device, wherein the display device includes an OLED screen, and the power supply circuit includes a buck-boost converter, wherein the power supply battery is connected to the power supply circuit, and the power supply circuit is connected to the display device, wherein: the power supply battery is used to transmit an input voltage to the buck-boost converter; the buck-boost converter is used to switch a current mode to a first mode or a second mode according to a magnitude relationship between the input voltage and a voltage threshold, so as to output a target power supply voltage; and the OLED screen in the display device is powered by the target power supply voltage; wherein, after switching the current mode from the first mode to the second mode, the switching time for switching the current mode from the second mode to the first mode is higher than a time threshold, and the time threshold is determined based on a refresh rate of the display device.

[0006] In a second aspect, a power supply method for a display device is provided, which is applied to a power supply circuit of a display device in a power supply architecture, wherein the power supply architecture also includes a power supply battery and a display device, and the display device includes an OLED screen. The method includes: obtaining an input voltage; switching a current mode to a first mode or a second mode according to a magnitude relationship between the input voltage and a voltage threshold to output a target power supply voltage; supplying power to the OLED screen through the above-mentioned target power supply voltage; wherein, after switching the current mode from the above-mentioned first mode to the second mode, the switching time for switching the current mode from the above-mentioned second mode to the first mode is higher than a time threshold, and the time threshold is determined based on the refresh rate of the above-mentioned display device.

[0007] In the present application, the power supply circuit of the display device can switch the current mode to the first mode or the second mode through a buck-boost converter according to the magnitude relationship between the input voltage from the power supply battery and the voltage threshold to output a target power supply voltage; and the OLED screen in the display device is powered by the target power supply voltage. Among them, after the current mode is switched from the first mode to the second mode, the switching time of switching the current mode from the second mode to the first mode is higher than the time threshold, and the time threshold is determined based on the refresh rate of the above-mentioned display device. In other words, the present application reduces the frequency of the output voltage by reducing the frequency of mode switching, thereby reducing the probability of water ripples. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic diagram of a power supply architecture provided in an embodiment of the present application;

[0009] Figure 2 is a schematic diagram of a power supply circuit provided in an embodiment of the present application;

[0010] Figure 3 is a schematic diagram of a power supply circuit of a display device provided in an embodiment of the present application;

[0011] Figure 4 is a schematic diagram of another power supply architecture provided in an embodiment of the present application;

[0012] Figure 5 is a schematic flow chart of a power supply method for a display device provided in an embodiment of the present application;

[0013] Figure 6 is a flowchart of a first specific example of a power supply method for a display device provided in an embodiment of the present application;

[0014] Figure 7 is a flowchart of a second specific example of the power supply method for a display device provided in an embodiment of the present application;

[0015] Figure 8It is a schematic diagram of a display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0017] Figure 1 Schematic diagram of a power supply architecture 100 provided in an embodiment of the present application. Figure 1 As shown, the power supply circuit 100 includes a power supply battery 101, a power supply circuit 102 (also referred to as a power management integrated circuit (PMIC)) and a display device 103. The power supply battery 101 is connected to the power supply circuit 102, and the power supply circuit 102 is connected to the display device 103. The display device 103 includes an organic light emitting diode (OLED) screen, and the power supply circuit 102 can obtain an input voltage from the power supply battery 101, and output a target power supply voltage to the above-mentioned display device 103, so as to realize power supply to the OLED screen in the display device 103. It should be understood that the OLED screen requires multiple different power supply voltages to power it in order to work properly. The output voltage includes a constant positive voltage ELVDD (4.6V) (i.e., the above-mentioned target power supply voltage). The voltage of the above-mentioned power supply battery generally varies in the range of 3.4V to 4.5V, and a 4.6V ELVDD voltage can be output through the above-mentioned power supply circuit.

[0018] However, the above method may cause voltage ripples, which may cause water ripples to appear on the screen, resulting in a poor user experience.

[0019] Figure 2 Schematic diagram of a power supply circuit 200 is shown. Figure 2 As shown, the power supply circuit 200 may include a boost converter 201. The boost converter 201 includes an inductor 2011, a first MOS transistor 2012 and a second MOS transistor 2013.

[0020] Exemplarily, when the input voltage of the power supply battery exceeds 4.5V, the first MOS tube 2012 can be complementary to the second MOS tube 2013 to enable the boost converter 201 to operate in a synchronous mode and output the target power supply voltage, i.e., the ELVDD voltage of 4.6V, to realize the power supply of the OLED screen in the above-mentioned display device. However, when the power supply battery is in a slow charging state, the superimposed battery load fluctuation will cause the input voltage of the boost converter to exceed 4.5V. In order to stabilize the ELVDD output voltage to 4.6V, the conduction time of the second MOS tube 2013 of the boost converter 201 is too short. When the conduction time limit of the second MOS tube 2013 is reached, the first MOS tube 2012 will operate in a low drop outregulator (LDO) mode. It should be understood that in the LDO mode, the first MOS tube 2012 is not completely turned on, and a certain voltage drop will be generated on the tube to extend the conduction time of the above-mentioned second MOS tube 2013. However, during the above-mentioned mode switching process, the ELVDD voltage will have a large voltage ripple, that is, when the input voltage changes from below 4.5V to above 4.5V, the boost converter 201 will immediately switch from the synchronous mode to the LDO mode, and when the input voltage switches from above 4.5V to below 4.5V, the boost converter 201 will immediately switch from the LDO mode to the above-mentioned synchronous mode. In other words, when the input voltage frequently jumps around 4.5V, a ripple of a certain frequency will be generated on the ELVDD voltage, causing a water ripple phenomenon of light and dark changes on the screen.

[0021] In view of this, an embodiment of the present application provides a power supply method and a power supply circuit for a display device, wherein the power supply circuit of the display device can switch the current mode to the first mode or the second mode through a step-up / step-down converter according to the magnitude relationship between the input voltage from the power supply battery and the voltage threshold, so as to output a target power supply voltage; and, power the OLED screen in the display device through the target power supply voltage. Among them, after the current mode is switched from the first mode to the second mode, the switching time of switching the current mode from the above-mentioned second mode to the first mode is higher than the time threshold, and the time threshold is determined based on the refresh rate of the above-mentioned display device. In other words, the present application reduces the frequency of the output voltage by reducing the frequency of mode switching, thereby reducing the probability of water ripples.

[0022] It should be understood that the display device involved in the embodiments of the present application may be a mobile phone, a tablet computer, a laptop computer, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a smart screen, an artificial intelligence (AI) speaker, a headset, a terminal in industrial control, a terminal in self driving, a terminal in remote medical surgery, a terminal in a smart grid, a terminal in transportation safety, a terminal in a smart city, a terminal in a smart home, a personal digital assistant (PDA), etc., and the embodiments of the present application are not limited to this.

[0023] In order to facilitate the understanding of the embodiments of the present application, the embodiments of the present application will be described more comprehensively with reference to the relevant drawings below. The preferred embodiments of the embodiments of the present application are given in the drawings. However, the embodiments of the present application can be implemented in many different forms and are not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the embodiments of the present application more thorough and comprehensive. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by technicians in the technical field belonging to the embodiments of the present application. The terms used in the specification of the embodiments of the present application herein are only for the purpose of describing specific embodiments and are not intended to limit the embodiments of the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] In the description of the embodiments of the present application, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the methods or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0025] It is understood that the terms "first", "second", etc. used in this application can be used in this article to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first MOS tube can be referred to as a second MOS tube, and similarly, a second MOS tube can be referred to as a first MOS tube. Both the first MOS tube and the second MOS tube are MOS tubes, but they are not the same MOS tube. And, the "connection" in the specification and claims of this application is an electrical connection.

[0026] It should be noted that, in this application, words such as "exemplarily" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplarily" or "for example" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplarily" or "for example" is intended to present related concepts in a specific way.

[0027] In addition, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can mean: a, or b, or c, or a and b, or a and c, or b and c, or a, b and c, where a, b, c can be single or multiple.

[0028] In order to make the purpose and technical solution of the present application clearer and more intuitive, the power supply method and power supply circuit of the display device provided by the embodiment of the present application will be described in detail below in combination with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

[0029] Figure 3 The schematic diagram of the power supply circuit 300 of the display device provided in this application is as follows Figure 3 As shown, the power supply circuit 300 of the display device may include a buck-boost converter 301. The buck-boost converter 301 may be composed of a first MOS transistor 3011, a second MOS transistor 3012, a third MOS transistor 3013, a fourth MOS transistor 3014 and an inductor 3015. Figure 3As shown, the first MOS tube 3011 can be connected in series with the second MOS tube 3012 to form a first series branch, the third MOS tube 3013 and the fourth MOS tube 3014 can be connected in series to form a second series branch, the second series branch and the first series branch are connected in parallel and connected through the inductor 3015.

[0030] It should be understood that the power supply circuit of the display device can be in two different modes, such as a first mode and a second mode. The power supply circuit of the display device can select to switch to a corresponding mode according to different input voltages to output a target power supply voltage in the corresponding mode.

[0031] Exemplarily, the power supply circuit of the display device can switch the current mode to the first mode when the input voltage is less than the voltage threshold so as to maintain the output target power supply voltage; alternatively, the power supply circuit of the display device can switch the current mode to the second mode when the input voltage is greater than or less than the voltage threshold so as to maintain the output target power supply voltage.

[0032] Figure 4 Schematic diagram of the power supply architecture 400 provided in this application. Figure 4 As shown, the power supply architecture 400 includes a power supply battery 401, a power supply circuit 402 of a display device, and a display device 403. The display device 403 includes an OLED screen 4031, and the power supply circuit 402 of the display device includes a buck-boost converter 4021 composed of a first MOS transistor 40211 (also represented by Q140211), a second MOS transistor 40212 (also represented by Q2 40212), a third MOS transistor 40213 (also represented by Q340213), a fourth MOS transistor 40214 (also represented by Q4 40214) and an inductor 40215 (also represented by L 40215). The connection relationship between the multiple circuit elements can be referred to in the above Figure 3 The description is not repeated here to avoid repetition, where:

[0033] The power supply battery 401 is used to transmit the input voltage V to the buck-boost converter 4021 in the power supply circuit 402 of the display device. in .

[0034] The step-up / step-down converter 4021 is used to adjust the input voltage V in With voltage threshold V th The current mode is switched to the first mode or the second mode to output the target supply voltage V out ; and, through the target supply voltage V outPower is supplied to the OLED screen 4031 in the display device 403 .

[0035] Exemplarily, the buck-boost converter 4021 may determine the input voltage V in From less than the voltage threshold V th changes to be greater than the voltage threshold V th In other words, the step-up / step-down converter 4021 can switch the current mode to the second mode when the input voltage V in From low to high crossing above the voltage threshold V th In this case, the current mode is switched from the first mode to the second mode.

[0036] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold. In other words, when the step-up / step-down converter 4021 determines the input voltage V in From less than the voltage threshold V th changes to be greater than the voltage threshold V th In the case of switching the current mode to the second mode, in order to ensure that the input voltage V in Less than the voltage threshold V th The target supply voltage V can be maintained at the output out In order to achieve efficient power supply to the OLED screen in the display device 403, the current mode may be the first mode.

[0037] Exemplarily, the buck-boost converter 4021 may also determine the input voltage V in From a voltage greater than the above threshold V th changes to be less than the voltage threshold V th In the case of , the current mode is switched to the first mode. That is, the buck-boost converter 4021 can determine the input voltage V in From high to low crossing voltage threshold V th In this case, the current mode is switched from the second mode to the above-mentioned first mode.

[0038] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold. in From a voltage greater than the above threshold V th changes to be less than the voltage threshold V thIn the case of switching the current mode to the first mode, in order to ensure that the input voltage V in Greater than the voltage threshold V th The target supply voltage V can be maintained at the output out To realize power supply to the OLED screen in the display device 403, the current mode may be the second mode.

[0039] In one possible implementation, the buck-boost converter 4021 can make the first MOS tube 40211 in a normally on state, and the third MOS tube 40213 and the fourth MOS tube 40214 are alternately turned on to switch the current mode to the first mode, and realize the output of the target power supply voltage in the first mode.

[0040] Exemplarily, the buck-boost converter 4021 can make the third MOS transistor 40213 turn on for a period of time, and then replace it with the fourth MOS transistor 40214 to achieve alternating conduction between the third MOS transistor 40213 and the fourth MOS transistor 40214.

[0041] Exemplarily, the buck-boost converter 4021 may also turn on the fourth MOS tube 40214 for a period of time and then replace it with the third MOS tube 40213 to achieve alternating conduction between the third MOS tube 40213 and the fourth MOS tube 40214, which is not limited in the present application.

[0042] Exemplarily, the buck-boost converter 4021 may also enable the second MOS tube 40212 to replace the first MOS tube 40211 in a normally on state, that is, the second MOS tube 40212 is in a normally on state, the first MOS tube 40211 is in a normally closed state, and the third MOS tube 40213 and the fourth MOS tube 40214 are alternately turned on to switch the current mode to the first mode, and realize the output of the target power supply voltage in the first mode, which is not limited in the present application.

[0043] In another possible implementation, the buck-boost converter 4021 can also make the first MOS tube 40211 and the second MOS tube 40212 alternately turned on, and make the third MOS tube 40213 and the fourth MOS tube 40214 alternately turned on, so as to switch the current mode to the second mode, and realize the output of the target power supply voltage in the second mode.

[0044] Exemplarily, the buck-boost converter 4021 can make the first MOS transistor 40211 turn on for a period of time, and then replace it with the second MOS transistor 40212, and turn them on cyclically in this order to achieve alternating conduction between the first MOS transistor 40211 and the second MOS transistor 40212. The third MOS transistor 40213 can also be turned on for a period of time, and then replaced with the fourth MOS transistor 40214, and turn them on cyclically in this order to achieve alternating conduction between the third MOS transistor 40213 and the fourth MOS transistor 40214. The first MOS transistor 40211 can be turned on synchronously with the third MOS transistor 40213, and the second MOS transistor 40212 can be turned on synchronously with the fourth MOS transistor 40214, which is not limited in the present application.

[0045] Exemplarily, the buck-boost converter 4021 may also make the first MOS transistor 40211 turned on for a period of time, and then replace it with the second MOS transistor 40212 turned on, and cyclically turn it on in this order to achieve alternating conduction between the first MOS transistor 40211 and the second MOS transistor 40212. The fourth MOS transistor 40214 may also be turned on for a period of time, and then replaced with the third MOS transistor 40213 turned on, and cyclically turn it on in this order to achieve alternating conduction between the third MOS transistor 40213 and the fourth MOS transistor 40214. The first MOS transistor 40211 may be turned on synchronously with the fourth MOS transistor 40214, and the second MOS transistor 40212 may be turned on synchronously with the third MOS transistor 40213, which is not limited in the present application.

[0046] Exemplarily, the buck-boost converter 4021 may also make the second MOS transistor 40212 turn on for a period of time, and then replace it with the first MOS transistor 40211 to turn on, and cyclically turn on in this order to achieve alternating conduction between the first MOS transistor 40211 and the second MOS transistor 40212. The fourth MOS transistor 40214 may also be turned on for a period of time, and then replaced with the third MOS transistor 40213 to turn on, and cyclically turn on in this order to achieve alternating conduction between the third MOS transistor 40213 and the fourth MOS transistor 40214. The first MOS transistor 40211 may be turned on synchronously with the third MOS transistor 40213, and the second MOS transistor 40212 may be turned on synchronously with the fourth MOS transistor 40214, which is not limited in the present application.

[0047] Exemplarily, the buck-boost converter 4021 may also make the second MOS transistor 40212 turn on for a period of time, and then replace it with the first MOS transistor 40211, and turn it on cyclically in this order to achieve alternating conduction between the first MOS transistor 40211 and the second MOS transistor 40212. The third MOS transistor 40213 may also be turned on for a period of time, and then replaced with the fourth MOS transistor 40214, and turn it on cyclically in this order to achieve alternating conduction between the third MOS transistor 40213 and the fourth MOS transistor 40214. The first MOS transistor 40211 may be turned on synchronously with the fourth MOS transistor 40214, and the second MOS transistor 40212 may be turned on synchronously with the third MOS transistor 40213, which is not limited in the present application.

[0048] It should be understood that after the buck-boost converter 4021 switches the current mode from the first mode to the second mode, the switching time for switching the current mode from the second mode to the first mode is higher than the time threshold, which can be determined based on the refresh rate of the display device.

[0049] It should also be understood that the power supply circuit of the display device shown above is merely exemplary and the present application does not limit this.

[0050] Exemplarily, the first MOS transistor 40211 may also be connected in series with the third MOS transistor 40213 to form a first series branch, the second MOS transistor 40212 and the fourth MOS transistor 40214 may be connected in series to form a second series branch, the second series branch is connected in parallel with the first series branch, and is connected through the inductor 40215. Alternatively, the first MOS transistor 40211 may also be connected in series with the fourth MOS transistor 40214 to form a first series branch, the second MOS transistor 40212 and the third MOS transistor 40213 may be connected in series to form a second series branch, the second series branch is connected in parallel with the first series branch, and is connected through the inductor 40215, which is not limited in the present application.

[0051] Figure 5 Schematic diagram of a power supply method 500 for a display device provided in the present application. The method 500 can be applied to a power supply circuit of a display device in a charging architecture, such as the above Figure 3 , Figure 4 The power supply circuit of the display device shown in FIG. Figure 5 As shown, the method 500 includes the following steps:

[0052] S501, a power supply circuit of a display device obtains an input voltage from a power supply battery through a buck-boost converter.

[0053] S502, the power supply circuit of the display device switches the current mode to the first mode or the second mode through the step-up / step-down converter according to the magnitude relationship between the input voltage and the voltage threshold, so as to output the target power supply voltage.

[0054] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold.

[0055] Exemplarily, the voltage threshold may also be referred to as a switching point voltage, which may be expressed as V th , can be taken as 4.5V. The above input voltage can be expressed as V in , the target supply voltage of the above output can be expressed as V out The power supply circuit of the display device can determine the above input voltage V through the step-up and step-down converter. in From a voltage greater than the above threshold V th changes to be less than the voltage threshold V th In the case of, the current mode is switched to the first mode. Alternatively, after determining the input voltage V in From less than the voltage threshold V th changes to be greater than the voltage threshold V th In the case of a fault, the current mode is switched to the second mode.

[0056] It should be understood that after the current mode is switched from the first mode to the second mode, the switching time of switching the current mode from the above mode to the first mode is greater than the time threshold. The time threshold may be determined based on the refresh rate of the above display device to avoid frequent mode switching resulting in output of a voltage with a high fluctuation frequency, thereby increasing the probability of water ripples.

[0057] S503, the power supply circuit of the display device supplies power to the OLED screen in the display device based on the target power supply voltage through a buck-boost converter.

[0058] It should be understood that the OLED screen requires multiple different power supply voltages to power it to work properly. Among them, the multiple different power supply voltages include the above-mentioned target power supply voltage V output by this application. out , that is, a constant positive voltage ELVDD of 4.6V.

[0059] In the present application, the power supply circuit of the display device can switch the current mode to the first mode or the second mode through a buck-boost converter according to the magnitude relationship between the input voltage from the power supply battery and the voltage threshold to output a target power supply voltage; and the OLED screen in the display device is powered by the target power supply voltage. Among them, after the current mode is switched from the first mode to the second mode, the switching time of switching the current mode from the second mode to the first mode is higher than the time threshold, and the time threshold is determined based on the refresh rate of the above-mentioned display device. In other words, the present application reduces the frequency of the output voltage by reducing the frequency of mode switching, thereby reducing the probability of water ripples.

[0060] Figure 6 Schematic diagram of a power supply method 600 for a display device provided in the present application. The method 600 can be applied to a power supply circuit of a display device in a charging architecture. Figure 6 As shown, the method 600 includes the following steps:

[0061] S601: A power supply circuit of a display device obtains an input voltage from a power supply battery through a step-up / step-down converter.

[0062] S602: The power supply circuit of the display device determines the magnitude relationship between the input voltage and the voltage threshold through a step-up / step-down converter.

[0063] Exemplarily, the voltage threshold may also be referred to as a switching point voltage, which may be expressed as V th , can be taken as 4.6V. The above input voltage can be expressed as V in The power supply circuit of the display device can compare the above input voltage with the voltage threshold through a step-up / step-down converter to determine the magnitude relationship between them.

[0064] S603, when it is determined that the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the power supply circuit of the display device obtains the time interval between the last switching of the previous current mode from the first mode to the second mode and then from the second mode to the first mode through the step-up / step-down converter.

[0065] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold. in From a voltage greater than the above threshold V th changes to be less than the voltage threshold V th In the case of obtaining the above-mentioned interval time, it can be determined before the above-mentioned S603 that in order to ensure that the input voltage V in Greater than the voltage threshold V thThe target supply voltage V can be maintained at the output out To realize power supply to the OLED screen in the display device, the current mode may be the second mode.

[0066] S604: The power supply circuit of the display device determines the magnitude relationship between the interval time and the above-mentioned time threshold through a step-up / step-down converter.

[0067] It should be understood that the time threshold is determined based on the refresh rate of the display device, such as the refresh rate of the OLED screen mentioned above.

[0068] S605 , when the interval time is greater than the time threshold, the power supply circuit of the display device switches the current mode from the second mode to the first mode through the buck-boost converter to output the target power supply voltage.

[0069] It should be understood that at the above input voltage V in is less than the above voltage threshold V th In the case of , both modes can output the target supply voltage V out To realize the power supply of the OLED screen in the display device. However, in order to achieve more efficient charging, the present application in is less than the above voltage threshold V th In this case, the first mode is preferred, that is, the current mode is switched to the above-mentioned first mode to output the target power supply voltage for power supply.

[0070] S606: The power supply circuit of the display device supplies power to the OLED screen of the display device based on the target power supply voltage through a buck-boost converter.

[0071] It should be understood that the OLED screen requires multiple different power supply voltages to power it to work properly. Among them, the multiple different power supply voltages include the above-mentioned target power supply voltage V output by this application. out , that is, a constant positive voltage ELVDD of 4.6V.

[0072] Optionally, following S602, when it is determined that the input voltage changes from less than the voltage threshold to greater than the voltage threshold, the power supply circuit of the display device can also execute S607 through the buck-boost converter, that is, switch the current mode from the first mode to the second mode to output the target power supply voltage.

[0073] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold. That is, when it is determined that the input voltage crosses the voltage threshold from low to high, that is, the input voltage V inGreater than the above voltage threshold of 4.5V V th In order to maintain the output target supply voltage V out , the current mode can be switched from the first mode to the above-mentioned second mode.

[0074] It should also be understood that before the above S607, that is, before the current mode is switched to the second mode, in order to ensure that the input voltage V in Less than the voltage threshold V th The target supply voltage V can be maintained at the output out In order to achieve efficient power supply to the OLED screen in the display device, the current mode may be the first mode.

[0075] Optionally, following the above S604, when the above interval time is less than or equal to the time threshold, the power supply circuit of the display device can also maintain the current mode as the second mode through the buck-boost converter to output the target power supply voltage.

[0076] It should be understood that the more frequent the mode switching, the higher the fluctuation frequency of the output voltage, and thus the higher the probability of water ripples appearing, and the easier it is for users to notice. Therefore, the present application can keep the current mode unchanged when the above interval time is less than or equal to the time threshold, so as to reduce the frequency of mode switching, so that the probability of water ripples appearing decreases as the fluctuation frequency of the output voltage decreases.

[0077] Optionally, following the above S604, when the above interval time is less than or equal to the time threshold, the power supply circuit of the display device may further perform S608 and S609 through the step-up / step-down converter.

[0078] S608, the power supply circuit of the display device obtains a new duration through the buck-boost converter, and determines whether the input voltage is lower than the voltage threshold when the sum of the interval time and the new time is greater than or equal to the time threshold.

[0079] S609: When it is determined that the input voltage is lower than the voltage threshold, the power supply circuit of the display device switches the current mode from the second mode to the first mode through the buck-boost converter.

[0080] It should be understood that in order to avoid frequent mode switching resulting in the output of a voltage with a high fluctuation frequency, thereby increasing the probability of water ripples, the present application can perform a mode switching operation when the sum of the above interval time and the new time is greater than or equal to the above time threshold, so as to reduce the mode switching frequency and reduce the probability of water ripples.

[0081] It should be understood that the present application can also perform the above-mentioned mode switching operation according to the current charging state to maintain the output target supply voltage under the input voltage corresponding to different charging states, so as to implement the power supply method of the display device provided by the present application.

[0082] Figure 7 Schematic diagram of a power supply method 700 for a display device provided in the present application. Meanwhile, the method 700 can be applied to a power supply circuit of a display device in a charging architecture. Figure 7 As shown, the method 700 includes the following steps:

[0083] S701, a power supply circuit of a display device obtains an input voltage from a power supply battery through a step-up / step-down converter.

[0084] S702: The power supply circuit of the display device determines the magnitude relationship between the input voltage and the voltage threshold through a step-up / step-down converter.

[0085] Exemplarily, the voltage threshold may also be referred to as a switching point voltage, which may be expressed as V th , can be taken as 4.5V. The above input voltage can be expressed as V in The power supply circuit of the display device can compare the above input voltage with the voltage threshold through a step-up / step-down converter to determine the magnitude relationship between them.

[0086] S703: When it is determined that the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the power supply circuit of the display device obtains the actual charging time through the step-up / step-down converter.

[0087] It should be understood that the first mode can be used only to maintain the output target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output target supply voltage when the input voltage is greater than or less than the voltage threshold. in From a voltage greater than the above threshold V th changes to be less than the voltage threshold V th In the case of obtaining the actual charging time, it can be determined before the above S703 to ensure that the input voltage V in Greater than the voltage threshold V th The target supply voltage V can be maintained at the output out To realize power supply to the OLED screen in the display device, the current mode may be the second mode.

[0088] S704: The power supply circuit of the display device determines whether it is currently in a preset charging state based on the above charging time through a buck-boost converter.

[0089] It should be understood that the charging process may include multiple different charging stages or charging states. For example, the preset charging state may be a slow charging state of the power supply battery or a charging state within a preset time period from the slow charging state.

[0090] S705: When the current charging state is not a preset charging state, the power supply circuit of the display device switches the current mode from the second mode to the first mode through a step-up / step-down converter to output a target power supply voltage.

[0091] Exemplarily, corresponding to the above S704, when the above preset charging state can be a slow charging state of the power supply battery or a charging state within a preset time period from the slow charging state, correspondingly, the non-preset charging state can be a non-slow charging state or a charging state within a non-preset time period from the slow charging state.

[0092] It should be understood that when the current charging state is not the preset charging state, the input voltage V in Typically, the voltage threshold V can be kept below 4.5V. th That is, in order to achieve high-efficiency power supply, the current mode can be switched from the second mode to the first mode to output the target power supply voltage.

[0093] S706: The power supply circuit of the display device supplies power to the OLED screen of the display device based on the target power supply voltage through the buck-boost converter.

[0094] As above, the OLED screen needs multiple different power supply voltages to power it to work properly. Among them, the multiple different power supply voltages include the above-mentioned target power supply voltage V output by this application. out , that is, a constant positive voltage ELVDD of 4.6V.

[0095] Optionally, following S704, when the current charging state is a preset charging state, the power supply circuit of the display device may further execute S707 through the buck-boost converter, that is, maintain the current mode as the second mode to output the target power supply voltage.

[0096] It should be understood that in the slow charging state, the input voltage V in Exceeding the voltage threshold of 4.5V V th Therefore, in the case where it is determined that the current charging state is the above-mentioned preset charging state, in order to avoid frequent switching of modes, the application can maintain the above-mentioned current mode as the second mode, output the target power supply, so as to realize the power supply to the OLED screen of the above-mentioned display device.

[0097] For example, if the current charging state is a charging state within a preset time period from the slow charging state included in the above-mentioned preset charging state, in this case, although the currently determined input voltage V in Less than the voltage threshold V th , but in the slow charging state that is about to enter, the input voltage V in will exceed 4.5V, and the first mode is only used for input voltages above V in is less than the above voltage threshold V th In other words, if the above charging state is not taken into account, it will be necessary to switch from the second mode to the first mode and then from the first mode to the second mode in a short period of time, resulting in frequent mode switching and increasing the probability of water ripples.

[0098] It should be understood that the present application can also combine the charging status and the above-obtained time interval between the last switching of the previous current mode from the first mode to the second mode and then from the second mode to the first mode to perform the above-mentioned mode switching operation to further reduce the mode switching frequency.

[0099] In one possible case, when it is determined that the above-mentioned time interval is greater than the above-mentioned time threshold, the power supply circuit of the display device can also determine the current charging state through the step-up / step-down converter, and when the current charging state is the above-mentioned non-preset charging state, switch from the above-mentioned second mode to the first mode.

[0100] Exemplarily, when it is determined that the time interval is greater than the time threshold and the current charging state is the non-preset charging state, the power supply circuit of the display device can switch from the second mode to the first mode through the buck-boost converter. in exceeds 4.5V for a short time, and the first mode is only used when the input voltage above V in is less than the above voltage threshold V th In this case, the target power supply voltage is maintained, resulting in the need to switch the current mode from the second mode to the first mode and then from the first mode to the second mode in a short period of time, resulting in frequent mode switching and increasing the probability of water ripples.

[0101] In another possible case, when the current charging state is the preset charging state, the power supply circuit of the display device can also maintain the second mode switching through the buck-boost converter to further reduce the frequency of mode switching and reduce the probability of water ripples.

[0102] It should be understood that the above-mentioned power supply battery, OLED screen and the power supply circuit of the display device provided in this application can be set in different devices.

[0103] Exemplarily, the power supply battery and the power supply circuit of the display device may be arranged in a power supply device, and the OLED screen is located in the display device.

[0104] Optionally, the present application may also set the above-mentioned power supply battery, OLED screen and the power supply circuit of the display device provided by the present application in the same device, such as a display device, to implement the power supply method of the display device provided by the present application, and the present application does not limit this.

[0105] Figure 8 Schematic diagram of a display device 800 provided in this application. Figure 8 As shown, the display device 800 includes a power supply battery 801, a power supply circuit 802 of the display device, and an OLED screen. The power supply circuit of the display device may include a buck-boost converter 8021, and the buck-boost converter 8021 may be composed of a first MOS tube 80211 (Q1 80211), a second MOS tube 80212 (Q2 802112), a third MOS tube 80213 (Q3 80213), a fourth MOS tube 80214 (Q41 80214) and an inductor 80215 (L 80215). Figure 8 As shown, the first MOS tube 80211 can be connected in series with the second MOS tube 80212 to form a first series branch, the third MOS tube 80213 and the fourth MOS tube 80214 can be connected in series to form a second series branch, the second series branch and the first series branch are connected in parallel and connected through the inductor 80215.

[0106] It should be understood that Figure 8 The display device 800 shown is merely exemplary and is not limited in this application.

[0107] It should also be understood that the above embodiments may be coupled to each other, and this application does not limit this. Moreover, the size of the sequence number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0108] The above contents are further detailed descriptions of the embodiments of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A power supply circuit for a display device, characterized in that: Applied to a power supply architecture, the power supply architecture further includes a power supply battery and a display device, the display device includes an OLED screen, the power supply circuit includes a step-up / step-down converter, the power supply battery is connected to the power supply circuit, and the power supply circuit is connected to the display device, wherein: The power supply battery is used to transmit input voltage to the buck-boost converter; The buck-boost converter is used to switch the current mode to the first mode or the second mode according to the magnitude relationship between the input voltage and the voltage threshold, so as to output a target power supply voltage; and to power the OLED screen in the display device through the target power supply voltage; Among them, after the current mode is switched from the first mode to the second mode, the switching time for switching the current mode from the second mode to the first mode is higher than a time threshold, and the time threshold is determined based on the refresh rate of the display device.

2. The power supply circuit according to claim 1, characterized in that: The first mode is used to maintain the output of the target supply voltage only when the input voltage is less than the voltage threshold; the second mode is used to maintain the output of the target supply voltage when the input voltage is greater than or less than the voltage threshold.

3. The power supply circuit according to claim 1, characterized in that: The buck-boost converter is used for: When it is determined that the input voltage changes from being less than the voltage threshold to being greater than the voltage threshold, switching the current mode from the first mode to the second mode; or, When it is determined that the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the current mode is switched from the second mode to the first mode.

4. The power supply circuit according to claim 3, characterized in that: The buck-boost converter is used for: Obtaining the time interval between the last switching of the previous current mode from the first mode to the second mode and then from the second mode to the first mode; Determine the magnitude relationship between the interval time and the time threshold; When the interval time is greater than the time threshold, the current mode is switched from the second mode to the first mode.

5. The power supply circuit according to claim 4, characterized in that: The buck-boost converter is used for: When the interval time is less than or equal to the time threshold, the current mode is maintained as the second mode.

6. The power supply circuit according to claim 5, characterized in that: The buck-boost converter is used for: When the sum of the interval time and the new time is greater than or equal to the time threshold, determining whether the input voltage is lower than the voltage threshold; When it is determined that the input voltage is lower than the voltage threshold, the current mode is switched from the second mode to the first mode.

7. The power supply circuit according to claim 3, characterized in that: The buck-boost converter is used for: Get the actual charging time; Determining a current charging state based on the actual charging time; Based on the current charging state, determining whether to switch the current mode from the second mode to the first mode; In a case where the previous charging state is a non-preset charging state, the current mode is switched from the second mode to the first mode.

8. The power supply circuit according to claim 7, characterized in that: The buck-boost converter is used for: When the current charging state is a preset charging state, maintaining the current mode as the second mode; Among them, the preset charging state is a slow charging state or a charging state within a preset time period from the slow charging state; the non-preset charging state is a non-slow charging state or a charging state within a non-preset time period from the slow charging state.

9. The power supply circuit according to any one of claims 1 to 8, characterized in that: The buck-boost converter is composed of a first MOS transistor, a second MOS transistor, a third MOS transistor, a fourth MOS transistor and an inductor, the first MOS transistor and the second MOS transistor are connected in series to form a first series branch, the third MOS transistor and the fourth MOS transistor are connected in series to form a second series branch, the first series branch and the second series branch are connected in parallel and connected through the inductor; Among them, in the first mode, the first MOS tube is always turned on, and the third MOS tube and the fourth MOS tube are turned on alternately; in the second mode, the first MOS tube and the second MOS tube are turned on alternately, and the third MOS tube and the fourth MOS tube are turned on alternately.

10. A power supply method for a display device, characterized in that: A power supply circuit for a display device in a power supply architecture, wherein the power supply architecture further includes a power supply battery and a display device, wherein the display device includes an OLED screen, and the method includes: Obtaining input voltage from the power supply battery; According to the magnitude relationship between the input voltage and the voltage threshold, the current mode is switched to the first mode or the second mode to output the target supply voltage; Powering the OLED screen in the display device via the target power supply voltage; Among them, after the current mode is switched from the first mode to the second mode, the switching time for switching the current mode from the second mode to the first mode is higher than a time threshold, and the time threshold is determined based on the refresh rate of the display device.

11. The method according to claim 10, characterized in that The first mode is used to maintain the output of the target supply voltage only when the input voltage is less than the voltage threshold; the second mode is used to maintain the output of the target supply voltage when the input voltage is greater than or less than the voltage threshold.

12. The method according to claim 10, characterized in that The step of switching the current mode to the first mode or the second mode according to the magnitude relationship between the input voltage and the voltage threshold comprises: When it is determined that the input voltage changes from being less than the voltage threshold to being greater than the voltage threshold, switching the current mode from the first mode to the second mode; or, When it is determined that the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the current mode is switched from the second mode to the first mode.

13. The method according to claim 12, characterized in that Before switching the current mode from the second mode to the first mode, the method further includes: Obtaining the time interval between the last switching of the previous current mode from the first mode to the second mode and then from the second mode to the first mode; Determine the magnitude relationship between the interval time and the time threshold; Switching the current mode from the second mode to the first mode includes: When the interval time is greater than the time threshold, the current mode is switched from the second mode to the first mode.

14. The method according to claim 13, characterized in that The method further comprises: When the interval time is less than or equal to the time threshold, the current mode is maintained as the second mode.

15. The method according to claim 14, characterized in that The method further comprises: The timer gets a new duration; When the sum of the interval time and the new time is greater than or equal to the time threshold, determining whether the input voltage is less than the voltage threshold; When it is determined that the input voltage is less than the voltage threshold, the current mode is changed from the second mode to the first mode.

16. The method according to claim 12, characterized in that Before switching the current mode from the second mode to the first mode when it is determined that the input voltage is less than the voltage threshold, the method further includes: Get the actual charging time; Determining a current charging state based on the actual charging time; Based on the current charging state, determining whether to switch the current mode from the second mode to the first mode; The step of switching the current mode from the second mode to the first mode when determining that the input voltage is less than the voltage threshold comprises: In a case where the previous charging state is a non-preset charging state, the current mode is switched from the second mode to the first mode.

17. The method according to claim 16, characterized in that The method further comprises: When the current charging state is a preset charging state, maintaining the current mode as the second mode; Among them, the preset charging state is a slow charging state or a charging state within a preset time period from the slow charging state; the non-preset charging state is a non-slow charging state or a charging state within a non-preset time period from the slow charging state.

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