Power supply circuit and control method thereof, power supply chip and display device

Abstract

The invention discloses a power supply circuit and a control method thereof, a power supply chip and a display device. The power supply circuit comprises an energy storage module which is connected between the input end and the output end of the power supply circuit; the switch module is connected with the energy storage module, and in a first state, the output end of the power supply circuit outputs current; and in the second state, the output end of the power supply circuit inputs current. The power supply circuit is optimized, and the display effect is improved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and particularly to a power supply circuit, a control method thereof, a power supply chip, and a display device. Background Art

[0002] With the continuous iteration and update of display devices, the power supply requirements for display devices are also constantly changing. Since different display devices have different power supply requirements, when the power supply circuit fails to meet the power supply requirements of the display device, it will have a greater impact on the display effect. Summary of the Invention

[0003] The present invention provides a power supply circuit, a control method thereof, a power supply chip, and a display device to optimize the power supply circuit and improve the display effect.

[0004] According to one aspect of the present invention, there is provided a power supply circuit, comprising:

[0005] An energy storage module connected between the input end and the output end of the power supply circuit;

[0006] A switching module connected to the energy storage module. In the first state, the output end of the power supply circuit outputs current; in the second state, the output end of the power supply circuit inputs current.

[0007] Optionally, the switching module is used to adjust the output voltage of the energy storage module according to a control signal; wherein, when the duty cycle of the control signal is different, the output voltage of the energy storage module is different.

[0008] Optionally, the energy storage module includes: a first energy storage unit, a second energy storage unit, and a third energy storage unit;

[0009] The first end of the first energy storage unit is connected to the input end of the power supply circuit at a first node, the second end of the first energy storage unit is connected to the first end of the third energy storage unit at a second node, the second end of the third energy storage unit is connected to the first end of the second energy storage unit at a third node, and the second end of the second energy storage unit is connected to the output end of the power supply circuit at a fourth node;

[0010] The first energy storage unit, the second energy storage unit, and the third energy storage unit are used to store or release electric energy; wherein, the first energy storage unit and the second energy storage unit store or release electric energy simultaneously;

[0011] Preferably, the first energy storage unit includes: a first inductor; the second energy storage unit includes: a first capacitor; the third energy storage unit includes: a second inductor;

[0012] The first end of the first inductor is connected to the first node, the second end of the first inductor is connected to the first end of the first capacitor at the second node, the second end of the first capacitor is connected to the first end of the second inductor at the third node, and the second end of the second inductor is connected to the output end of the power supply circuit at the fourth node; the like-named ends of the first inductor and the second inductor are associated.

[0013] Optionally, the switching module includes: a first switching unit and a second switching unit;

[0014] The first end of the first switching unit is connected to the second end of the first energy storage unit at the second node, and the second end of the first switching unit is grounded;

[0015] The first end of the second switching unit is connected to the first node, and the second end of the second switching unit is connected to the first end of the second energy storage unit at the third node;

[0016] Preferably, the output end of the power supply circuit is used to connect to a load;

[0017] Before the load is powered on, when the first switching unit is turned on, it is used to control the first energy storage unit and the second energy storage unit to release electric energy, and the third energy storage unit stores electric energy;

[0018] When the second switching unit is turned on, it is used to control the first energy storage unit and the second energy storage unit to store electric energy;

[0019] After the load is powered on, when the first switching unit is turned on, it is used to control the first energy storage unit and the second energy storage unit to store electric energy;

[0020] When the second switching unit is turned on, it is used to control the first energy storage unit and the second energy storage unit to release electric energy, and the third energy storage unit stores electric energy;

[0021] Preferably, the state before the load is powered on is the first state; the state after the load is powered on is the second state;

[0022] Preferably, the first switching unit includes: a first transistor, and the second switching unit includes a second transistor; the first end of the first transistor is connected to the second end of the first energy storage unit at the second node, and the second end of the first transistor is grounded; the first end of the second transistor is connected to the input end of the power supply circuit at the first node, and the second end of the second transistor is connected to the first end of the second energy storage unit at the third node;

[0023] When the duty cycle of the control terminal signal of the first transistor is greater than a first preset threshold, the energy storage module outputs a negative voltage to the output terminal of the power supply circuit;

[0024] When the duty cycle of the control terminal signal of the first transistor is equal to the first preset threshold, the energy storage module outputs a zero voltage to the output terminal of the power supply circuit;

[0025] When the duty cycle of the control terminal signal of the first transistor is less than the first preset threshold, the energy storage module outputs a positive voltage to the output terminal of the power supply circuit;

[0026] Preferably, the first transistor and the second transistor are used to conduct or cut off according to their respective duty cycles; wherein, the duty cycle of the second transistor is complementary to the duty cycle of the first transistor;

[0027] Preferably, the on-off states of the first transistor and the second transistor are different.

[0028] Optionally, the power supply circuit further includes: a first filtering unit and a second filtering unit;

[0029] The first end of the first filtering unit is connected to the input end of the power supply circuit at the first node, and the second end of the first filtering unit is grounded; the first end of the second filtering unit is connected to the output end of the power supply circuit at the fourth node, and the second end of the second filtering unit is grounded.

[0030] According to another aspect of the present invention, there is provided a control method for a power supply circuit, the power supply circuit including: an energy storage module and a switching module; the energy storage module is connected between the input end and the output end of the power supply circuit; the switching module is connected to the energy storage module;

[0031] The control method of the power supply circuit includes:

[0032] Before the load is powered on, the energy storage module outputs current through the output terminal of the power supply circuit;

[0033] After the load is powered on, the current in the load is input through the output terminal of the power supply circuit.

[0034] Optionally, the step of before the load is powered on, the energy storage module outputs current through the output terminal of the power supply circuit includes:

[0035] Controlling the first switch unit to conduct and the second switch unit to cut off, so that the first energy storage unit and the second energy storage unit release electric energy, and the third energy storage unit stores electric energy;

[0036] Control the first switching unit to turn off and the second switching unit to turn on, so that the first energy storage unit and the second energy storage unit store electrical energy.

[0037] After the load is powered on, the current in the load is input through the output terminal of the power supply circuit, including:

[0038] Control the first switching unit to turn on and the second switching unit to turn off, so that the first energy storage unit and the second energy storage unit store electrical energy;

[0039] Control the first switching unit to turn off and the second switching unit to turn on, so that the first energy storage unit and the second energy storage unit release electrical energy, and the third energy storage unit stores electrical energy.

[0040] Optionally, the control method of the power supply circuit further includes:

[0041] When the duty cycle of the control terminal signal of the first transistor is greater than the first preset threshold, the energy storage module outputs a negative voltage to the output terminal of the power supply circuit;

[0042] When the duty cycle of the control terminal signal of the first transistor is equal to the first preset threshold, the energy storage module outputs a zero voltage to the output terminal of the power supply circuit;

[0043] When the duty cycle of the control terminal signal of the first transistor is less than the first preset threshold, the energy storage module outputs a positive voltage to the output terminal of the power supply circuit.

[0044] According to another aspect of the present invention, there is provided a power supply chip, including: the power supply circuit according to any embodiment of the present invention.

[0045] According to another aspect of the present invention, there is provided a display device, including: a display panel and the power supply chip according to any embodiment of the present invention.

[0046] The technical solution provided by the embodiments of the present invention can control the energy storage module to store or release electrical energy by setting a switching module, so as to adjust the voltage at the output terminal of the power supply circuit. For example, when the output voltage at the output terminal of the power supply circuit is a positive voltage, by powering on the second power supply voltage before the first power supply voltage, the power supply circuit has a source function and realizes the output of current. When the first power supply voltage is powered on, the power supply circuit has a sink function and realizes the input of current. Therefore, the power supply circuit provided by the present invention has more functions and has a better display effect.

[0047] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become readily apparent from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0049] Figure 1 is a schematic structural diagram of a power supply circuit provided according to an embodiment of the present invention;

[0050] Figure 2 is a schematic structural diagram of another power supply circuit provided according to an embodiment of the present invention;

[0051] Figure 3 is a schematic structural diagram of yet another power supply circuit provided according to an embodiment of the present invention;

[0052] Figure 4 is a power supply timing diagram of a power supply circuit provided according to an embodiment of the present invention;

[0053] Figure 5 is a simulation diagram of the output voltage and duty cycle of a power supply circuit provided according to an embodiment of the present invention;

[0054] Figure 6 is a simulation waveform diagram of the output voltage of a power supply circuit provided according to an embodiment of the present invention;

[0055] Figure 7 is a simulation waveform diagram of the output voltage of another power supply circuit provided according to an embodiment of the present invention;

[0056] Figure 8 is a simulation waveform diagram of the output voltage of yet another power supply circuit provided according to an embodiment of the present invention;

[0057] Figure 9 is a schematic diagram of the current flow direction in the first stage of a power supply circuit provided according to an embodiment of the present invention;

[0058] Figure 10 is a schematic diagram of the current flow direction in the second stage of a power supply circuit provided according to an embodiment of the present invention;

[0059] Figure 11 is a flowchart of a control method for a power supply circuit provided according to an embodiment of the present invention;

[0060] Figure 12 It is a flowchart of a specific implementation method of S110 provided according to an embodiment of the present invention;

[0061] Figure 13 It is a flowchart of a specific implementation method of S120 provided according to an embodiment of the present invention;

[0062] Figure 14 It is a schematic structural diagram of a display device provided according to an embodiment of the present invention. Detailed implementation manners

[0063] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0064] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0065] The embodiment of the present invention provides a power supply circuit, which can be integrated into a power supply chip. Figure 1 It is a schematic structural diagram of a power supply circuit provided according to an embodiment of the present invention. Refer to Figure 1 , this power supply circuit includes: an energy storage module 1 and a switching module 2. The energy storage module 1 is connected between the input terminal Vin and the output terminal Vout of the power supply circuit. The switching module 2 is connected to the energy storage module 1. In the first state, the output terminal Vout of the power supply circuit outputs current; in the second state, the output terminal Vout of the power supply circuit inputs current.

[0066] The power supply circuit provided by the embodiments of the present invention can be applied to a display device. The display device includes a display panel, and the display panel includes a plurality of sub-pixels and a plurality of signal lines. The sub-pixel includes a pixel circuit and a light-emitting element. The pixel circuit is connected to the light-emitting element, and the pixel circuit is configured to drive the light-emitting element to emit light for display. The light-emitting element may include at least one of a red light-emitting element, a green light-emitting element, a blue light-emitting element, and a white light-emitting element. The plurality of signal lines include a first power supply line and a second power supply line. The pixel circuit and the light-emitting element are connected between the first power supply line and the second power supply line, and the pixel circuit and the light-emitting element operate based on the power supply voltages provided by the first power supply line and the second power supply line. For example, the pixel circuit is connected to the first power supply line, the first electrode of the light-emitting element is connected to the pixel circuit, and the second electrode of the light-emitting element is connected to the second power supply line. The first power supply line transmits a first power supply voltage, and the second power supply line transmits a second power supply voltage. In some exemplary embodiments, the first power supply voltage is a high-level voltage, and the second power supply voltage is a low-level voltage. The first power supply voltage is higher than the second power supply voltage.

[0067] Wherein, the pixel circuit includes a transistor and a capacitor. In some exemplary embodiments, the pixel circuit applied to the display panel may adopt a pixel circuit in the form of 7T1C, etc. The 7T1C pixel circuit includes a circuit composed of 7 transistors and 1 capacitor. The type of the transistor in the pixel circuit may be a low-temperature polycrystalline silicon thin-film transistor, or an oxide thin-film transistor, or a combination of a low-temperature polycrystalline silicon thin-film transistor and an oxide thin-film transistor. The active layer of the low-temperature polycrystalline silicon thin-film transistor adopts low-temperature poly-silicon (LTPS), and the active layer of the oxide thin-film transistor adopts an oxide, such as indium gallium zinc oxide (IGZO). When different transistors are used in the display panel, the required power supply voltages are different. For example, the magnitude of the required power supply voltage, the output or input drive current, etc. are different. When the display panel operates in different display modes, the required power supply voltages may also be different.

[0068] In some exemplary embodiments, the power supply circuit may be integrated in a power supply chip. The first power supply port of the power supply chip is connected to the first power supply line, the second power supply port of the power supply chip is connected to the second power supply line, and the output end of the power supply circuit is connected to the second power supply port. The power supply circuit can provide different power supply voltages for the display panel.

[0069] Exemplarily, the switch module 2 may include a plurality of switch units, and the switch units may include types such as transistors. The energy storage module 1 may include a plurality of energy storage units, and the energy storage units may include types such as capacitors and inductors. The switch module 2 can control the on / off states of the respective switch units, and thereby control the states of the respective energy storage units for storing or releasing electrical energy, thereby achieving voltage regulation of the output terminal Vout of the power supply circuit. Exemplarily, the output terminal Vout of the power supply circuit can output a positive voltage.

[0070] To ensure reliable power consumption of the sub-pixels when the output terminal Vout of the power supply circuit outputs a positive voltage, the second power supply voltage transmitted by the second power supply line can supply power to the sub-pixels prior to the first power supply voltage transmitted by the first power supply line, where the line connected to the output terminal Vout of the power supply circuit is the second power supply line. That is, in the first state, the second power supply voltage connected to the sub-pixel is a positive voltage, the first power supply voltage connected to the sub-pixel is 0, and the voltage in the second power supply line is higher than the voltage in the first power supply line. Therefore, the power supply circuit can output current through the output terminal Vout, and the power supply circuit has a source function. Exemplarily, the output terminal Vout can be connected to the ground terminal, so that the current output by the output terminal Vout can directly flow into the ground terminal.

[0071] When the second power supply voltage is fully established and the second power supply voltage is in a stable state, the first power supply voltage is used to supply power to the sub-pixels. That is, in the second state, both the first power supply voltage and the second power supply voltage of the sub-pixel are positive voltages, and the first power supply voltage is higher than the second power supply voltage. The current flows from the sub-pixel into the second power supply line through the first power supply line, causing the current at the output terminal Vout of the power supply circuit to reverse and input into the power supply circuit through the output terminal Vout of the power supply circuit. Since the second power supply voltage has been fully established and the second power supply voltage is in a stable state, that is, the power supply circuit is in a stable power supply state, the power supply circuit has a good ability to receive current. At this time, even if the current is input into the power supply circuit through the output terminal Vout of the power supply circuit, it will not cause damage to the power supply circuit. Therefore, the power supply circuit also has a sink function.

[0072] Compared with the prior art method of first powering on with the first power supply voltage and then powering on with the second power supply voltage, or the method of powering on with the first power supply voltage and the second power supply voltage simultaneously, if the second power supply voltage is a positive voltage, during the power-on stage of the second power supply voltage, since the voltage is not fully established, at this time, if the current input into the power supply circuit through the output terminal Vout is too large, the power supply circuit may be damaged due to its inability to withstand the current, causing abnormalities in the display panel during the process of lighting up the screen. Therefore, the power-on power supply provided by the prior art is only applicable to sub-pixels with a second power supply voltage of a negative voltage or 0 voltage.

[0073] In the technical solution provided by the embodiment of the present invention, by setting a switching module, the energy storage module can be controlled to store or release electric energy, so as to adjust the voltage at the output end of the power supply circuit. For example, when the output voltage at the output end of the power supply circuit is a positive voltage, by powering on the second power supply voltage before the first power supply voltage, the power supply circuit has the source function, realizing the output of current. When the first power supply voltage is powered on, the power supply circuit has the sink function, realizing the input of current. Therefore, the power supply circuit provided by the present invention has more functions and has a better display effect.

[0074] Continuing to refer to Figure 1 , based on the above embodiments, optionally, the switching module 2 is used to adjust the output voltage of the energy storage module 1 according to the duty cycle of the control signal; wherein, when the duty cycle of the control signal is different, the output voltage of the energy storage module 1 is different.

[0075] Specifically, when the switching module 2 receives the control signal, the signal can act on each switching unit in the switching module 2, and each switching unit can be turned on or off according to the duty cycle of the control signal. Since the switching module 2 is connected to the energy storage module 1, the on or off of each switching unit can control each energy storage unit in the energy storage module 1 to store or release electric energy. By storing or releasing electric energy by each energy storage unit, the energy storage module 1 can output different magnitudes of voltage, thereby realizing the adjustment of the output voltage of the output end Vout of the power supply circuit.

[0076] Exemplarily, when the duty cycle provided by the control signal is less than 0.5, the output end Vout of the power supply circuit outputs a positive voltage. When the duty cycle provided by the control signal is equal to 0.5, the voltage output by the output end Vout of the power supply circuit is 0V. When the duty cycle provided by the control signal is greater than 0.5, the output end Vout of the power supply circuit outputs a negative voltage. Therefore, the switching module 2 can control the power supply circuit to switch between positive voltage, negative voltage and 0 voltage according to different control signals.

[0077] In another implementation manner, when the duty cycle provided by the control signal is fixed, by adjusting the input voltage of the input end Vin of the power supply circuit, the output voltage of the output end Vout can also be adjusted.

[0078] In the technical solution provided by the embodiment of the present invention, the switching module can control the energy storage module to store or release electric energy according to different control signals, so as to adjust the voltage at the output end of the power supply circuit, thereby realizing the switching between positive voltage, 0 voltage and negative voltage at the output end of the power supply circuit, making the power supply circuit have higher applicability and can be applied to various sub-pixels with different power consumption requirements.

[0079] Figure 2Schematic diagram of another power supply circuit provided by an embodiment of the present invention. Refer to Figure 2 , based on the above embodiments, optionally, the energy storage module 1 includes: a first energy storage unit 11, a second energy storage unit 12, and a third energy storage unit 13. The first end of the first energy storage unit 11 is connected to the input end Vin of the power supply circuit at a first node, the second end of the first energy storage unit 11 is connected to the first end of the third energy storage unit 13 at a second node, the second end of the third energy storage unit 13 is connected to the first end of the second energy storage unit 12 at a third node, and the second end of the second energy storage unit 12 is connected to the output end Vout of the power supply circuit at a fourth node. The first energy storage unit 11, the second energy storage unit 12, and the third energy storage unit 13 are used to store or release electric energy; wherein, the first energy storage unit 11 and the second energy storage unit 12 store or release electric energy simultaneously.

[0080] Among them, the first energy storage unit 11, the second energy storage unit 12, and the third energy storage unit 13 can store or release electric energy according to different switching states of the switching module 2. So that the switching module 2 adjusts the voltage of the output end Vout of the power supply circuit through different control signals.

[0081] Specifically, when the second power supply voltage ELVSS is powered on and the first power supply voltage ELVDD is not powered on, the switching module 2 can supply power to the second energy storage unit 12 from the input end Vin of the power supply circuit according to the control signal, and the second energy storage unit 12 starts to store energy. At this time, the current in the power supply circuit passes through the switching module 2 and the second energy storage unit 12 and is then output from the output end Vout of the power supply circuit to the ground terminal. The second energy storage unit 12 and the first energy storage unit 11 can be inductors with associated same-name terminals. Therefore, when the second energy storage unit 12 stores energy, the first energy storage unit 11 can also store energy simultaneously.

[0082] As the switching module 2 switches the conduction or cutoff of each switching unit according to the control signal, the first energy storage unit 11 and the second energy storage unit 12 switch from the energy storage state to the electric energy release state, and supply power to the third energy storage unit 13 through the second energy storage unit 12, and the third energy storage unit 13 starts to store energy.

[0083] When the second energy storage unit 12 stores or releases electric energy, the direction of its current flow is always towards the output end Vout of the power supply circuit. Therefore, when the second power supply voltage ELVSS is powered on and the first power supply voltage ELVDD is not powered on, the power supply circuit has the source function.

[0084] When both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, the switch module 2 can discharge the first energy storage unit 11 and the second energy storage unit 12 according to the control signal. At the same time, the third energy storage unit 13 receives the electrical energy of the second energy storage unit 12 for charging. At this time, the current in the sub-pixel 3 is input into the power supply circuit through the output terminal Vout of the power supply circuit.

[0085] As the switch module 2 switches the conduction or cutoff of each switch unit according to the control signal, the first energy storage unit 11 and the second energy storage unit 12 switch from the state of releasing electrical energy to the energy storage state. The first energy storage unit 11 stores energy according to the electrical energy input from the input terminal Vin of the power supply circuit, and at the same time, the second energy storage unit 12 also starts to store energy.

[0086] When the second energy storage unit 12 stores or releases electrical energy, the direction of its current flow is from the sub-pixel 3 to the output terminal Vout of the power supply circuit. Therefore, when both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, the power supply circuit has a sink function.

[0087] The power supply circuit provided by the embodiment of the present invention has a source function when the second power supply voltage is powered on and the first power supply voltage is not powered on, that is, the power supply circuit outputs current through the output terminal. When both the second power supply voltage and the first power supply voltage are powered on, it has a sink function, that is, current can be input to the output terminal of the power supply circuit. The present invention enables the power supply circuit to have more functions and is applicable to sub-pixels with a positive voltage requirement for the second power supply voltage.

[0088] Continue to refer to Figure 2 , on the basis of the above embodiments, optionally, the switch module 2 includes: a first switch unit 21 and a second switch unit 22. The first end of the first switch unit 21 is connected to the second end of the first energy storage unit 11 at a second node, and the second end of the first switch unit 21 is grounded. The first end of the second switch unit 22 is connected to the input terminal Vin of the power supply circuit, and the second end of the second switch unit 22 is connected to the first end of the second energy storage unit 12 at a third node.

[0089] Wherein, the first switch unit 21 and the second switch unit 22 can be turned on or off according to the control signal. Exemplarily, the first switch unit 21 and the second switch unit 22 are not turned on or off simultaneously. When the first switch unit 21 is turned on, the second switch unit 22 is in the off state; when the first switch unit 21 is turned off, the second switch unit 22 is in the on state.

[0090] Specifically, during the power-on stage of the second power supply voltage ELVSS, the voltage of the second power supply voltage ELVSS gradually rises from 0 to a stable voltage value. At this time, the first power supply voltage ELVDD is in an unpowered state and the first power supply voltage ELVDD is 0. Therefore, the second power supply voltage ELVSS is higher than the first power supply voltage ELVDD. When the first switching unit 21 is turned off and the second switching unit 22 is turned on, the input terminal Vin of the power supply circuit supplies power to the second energy storage unit 12 through the second switching unit 22, and the second energy storage unit 12 starts to store energy. The second energy storage unit 12 and the first energy storage unit 11 can be inductors with associated same-named terminals. Therefore, the first energy storage unit 11 also stores energy. The third energy storage unit 13 also stores energy due to different voltage drops across its two ends.

[0091] During this stage, if the energy stored in the third energy storage unit 13 is sufficient, the third energy storage unit 13 can also supply power to the first energy storage unit 11 instead of the input terminal Vin of the power supply circuit. At the same time, the second energy storage unit 12 also stores energy. At this time, the current flow direction in the power supply circuit is from the second energy storage unit 12 to the output terminal Vout of the power supply circuit.

[0092] When the first switching unit 21 is turned on and the second switching unit 22 is turned off, the first energy storage unit 11 and the second energy storage unit 12 start to release electrical energy and supply power to the third energy storage unit 13 through the second energy storage unit 12, and the third energy storage unit 13 starts to store energy. At this time, the current flow direction of the second energy storage unit 12 remains unchanged and outputs current through the output terminal Vout of the power supply circuit. Therefore, during the power-on stage of the second power supply voltage ELVSS, the on-off states of the first switching unit 21 and the second switching unit 22 do not affect the current flow direction of the output terminal Vout of the power supply circuit, and the power supply circuit always has a source function.

[0093] When both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, the first power supply voltage ELVDD is higher than the second power supply voltage ELVSS. When the first switching unit 21 is turned off and the second switching unit 22 is turned on, the first energy storage unit 11 and the second energy storage unit 12 release electrical energy, and the first energy storage unit 11 supplies power to the third energy storage unit 13, and the third energy storage unit 13 starts to store energy. Since the first power supply voltage ELVDD is higher than the second power supply voltage ELVSS, current can pass through the sub-pixel 3 to the output terminal Vout of the power supply circuit.

[0094] When the first switching unit 21 is turned on and the second switching unit 22 is turned off, the input terminal Vin of the power supply circuit supplies power to the first energy storage unit 11, and the first energy storage unit 11 starts to store energy. At the same time, the second energy storage unit 12 also stores energy.

[0095] At this stage, when the energy stored in the third energy storage unit 13 is sufficient, the third energy storage unit 13 can also replace the input terminal Vin of the power supply circuit and supply power to the second energy storage unit 12. At the same time, the first energy storage unit 11 also stores energy. At this time, the current flow direction of the second energy storage unit 12 remains unchanged. Therefore, when both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, the on-off states of the first switch unit 21 and the second switch unit 22 do not affect the current flow direction of the output terminal Vout of the power supply circuit, and the power supply circuit always has a sink function.

[0096] Figure 3 FIG. is a schematic structural diagram of another power supply circuit provided by an embodiment of the present invention. Combining Figure 2 and Figure 3 , on the basis of the above embodiments, optionally, the power supply circuit further includes: a first filtering unit 41 and a second filtering unit 42. The first end of the first filtering unit 41 is connected to the input terminal Vin of the power supply circuit at a first node, and the second end of the first filtering unit 41 is grounded; the first end of the second filtering unit 42 is connected to the output terminal Vout of the power supply circuit at a fourth node, and the second end of the second filtering unit 42 is grounded.

[0097] Wherein, the first filtering unit 41 may include a second capacitor C2, and the second filtering unit 42 may include a third capacitor C3. The second capacitor C2 can be used to filter the input voltage of the input terminal Vin of the power supply circuit, and the third capacitor C3 can be used to filter the output voltage of the output terminal Vout of the power supply circuit. By providing the first filtering unit 41 and the second filtering unit 42, the power supply stability of the power supply circuit can be improved.

[0098] Continuing to refer to Figure 3 , on the basis of the above embodiments, optionally, the first energy storage unit 11 includes: a first inductor L1; the second energy storage unit 12 includes: a first capacitor C1; the third energy storage unit 13 includes: a second inductor L2. The first end of the first inductor L1 is connected to the first node, the second end of the first inductor L1 is connected to the first end of the first capacitor C1 at a second node, the second end of the first capacitor C1 is connected to the first end of the second inductor L2 at a third node, and the second end of the second inductor L2 is connected to the output terminal Vout of the power supply circuit at a fourth node; the same-named ends of the first inductor L1 and the second inductor L2 are associated.

[0099] Among them, the first inductor L1 and the second inductor L2 are associated with the same-named terminals. Exemplarily, one end of the first inductor L1 close to the input terminal Vin of the power supply circuit and one end of the second inductor L2 close to the output terminal Vout of the power supply circuit can be used as the same-named terminals. Therefore, when one of the first inductor L1 or the second inductor L2 stores energy, due to the interaction of magnetic fields, the other inductor can also store energy simultaneously. Also, since both the first inductor L1 and the second inductor L2 are connected to the first capacitor C1, when the first inductor L1 or the second inductor L2 discharges, the first inductor L1 or the second inductor L2 can output a current in the form of a triangular wave, which can be equivalent to an alternating current and can charge the first capacitor C1.

[0100] By charging and discharging the first inductor L1, the second inductor L2 or the first capacitor C1, the present invention can achieve voltage regulation of the output terminal Vout of the power supply circuit. This regulation method is simple and has good controllability.

[0101] Figure 4 For the power supply timing diagram of a power supply circuit provided by an embodiment of the present invention, in combination with Figure 3 and Figure 4 , when the second power supply voltage ELVSS starts to power on and after a delay of T_Delay time, the first power supply voltage ELVDD starts to power on.

[0102] Among them, within the time of T_Delay, the voltage of the second power supply voltage ELVSS gradually rises from 0 to a stable voltage state. In this timing, the second power supply voltage ELVSS of sub-pixel 3 is higher than the first power supply voltage ELVDD, and the current in the power supply circuit is output through the output terminal Vout of the power supply circuit, and the power supply circuit has a source function.

[0103] When the delay of T_Delay time has passed, the second power supply voltage ELVSS is fully established and in a stable power supply state. At this time, the first power supply voltage ELVDD powers on. Since the first power supply voltage ELVDD is higher than the second power supply voltage ELVSS, the current in sub-pixel 3 flows from the first power line to the second power line and is input into the power supply circuit through the output terminal Vout of the power supply circuit, and the power supply circuit has a sink function.

[0104] If it is necessary to continue to boost the first power supply voltage ELVDD and the second power supply voltage ELVSS, since both the second power supply voltage ELVSS and the first power supply voltage ELVDD are in a stable power supply state, the power supply circuit has a good ability to receive current, and it can be controlled that the first power supply voltage ELVDD boosts first before the second power supply voltage ELVSS, and at this time the power supply circuit still maintains a stable power supply state.

[0105] Continue to refer to Figure 3, based on the above embodiments, optionally, the first switching unit 21 includes: a first transistor Q1, and the second switching unit 22 includes: a second transistor Q2; a first end of the first transistor Q1 is connected to a second end of the first energy storage unit 11 at a second node, and a second end of the first transistor Q1 is grounded; a first end of the second transistor Q2 is connected to an input end Vin of the power supply circuit at a first node, and a second end of the second transistor Q2 is connected to a first end of the second energy storage unit 12 at a third node. When the duty cycle of the control signal of the first transistor Q1 is greater than a first preset threshold, the energy storage module outputs a negative voltage to an output end Vout of the power supply circuit. When the duty cycle of the control signal of the first transistor Q1 is equal to the first preset threshold, the energy storage module outputs a zero voltage to the output end Vout of the power supply circuit. When the duty cycle of the control signal of the first transistor Q1 is less than the first preset threshold, the energy storage module outputs a positive voltage to the output end Vout of the power supply circuit.

[0106] Wherein, the first transistor Q1 and the second transistor Q2 are used to conduct or turn off according to their respective duty cycles. The duty cycle refers to the ratio of the time when the signal is at a high level to the entire cycle time within one cycle. Exemplarily, when the control signal is at a high level, the transistor conducts. Different on-off states of the first transistor Q1 and the second transistor Q2 can be used to adjust the charge and discharge states of the first inductor L1, the second inductor L2, and the first capacitor C1, and further adjust the output voltage of the output end Vout of the power supply circuit.

[0107] When the second power supply voltage ELVSS is powered on and the first power supply voltage ELVDD is not powered on, if the first transistor Q1 is turned off and the second transistor Q2 is turned on, the second inductor L2 stores energy. Due to the association of the same-named terminals of the first inductor L1 and the second inductor L2, the first inductor L1 stores energy simultaneously. If the first transistor Q2 is turned on and the second transistor Q2 is turned off, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy.

[0108] When both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, if the first transistor Q1 is turned off and the second transistor Q2 is turned on, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy. If the first transistor Q2 is turned on and the second transistor Q2 is turned off, the first inductor L1 and the second inductor L2 store energy.

[0109] The voltage of the power supply circuit will be specifically described below according to the on-off states of the first transistor Q1 and the second transistor Q2.

[0110] When the first transistor Q1 is turned on and the second transistor Q2 is turned off,

[0111] V A = 0;

[0112] V L1 = V 1 - 0 = V 1 ;

[0113] V L2 = -V 1 ;

[0114] V B = V L2 + V 2 = V 2 - V 1 ;

[0115] V C1 = V A - V B = V L2 + V 2 = V 1 - V 2 ;

[0116] When the first transistor Q1 is turned off and the second transistor Q2 is turned on,

[0117] V B = V 1 ;

[0118] V L2 = V 1 - V 2 ;

[0119] V C1 = V 1 - V 2 ;

[0120] V A = V B + V C1 = 2V 1 - V 2 ;

[0121] V L1 = V 1 - V A = V 2 - V 1 ;

[0122] where, V A is the voltage at point A, V B is the voltage at point B, V L1 is the voltage across the first inductor L1, V L2 is the voltage across the second inductor L2, V C1 is the voltage across the first capacitor C1, V 2 is the output voltage at the output terminal of the power supply circuit, V 1 is the input voltage at the input terminal of the power supply circuit.

[0123] Based on the above formula and the volt - second balance, the following derivation is as follows:

[0124] V 1 ×D×T S +(V 2 -V 1 )×(1 - D)×T S =0;

[0125] V 2 / Vin=(2D - 1) / (D - 1)=(1 - 2D) / (1 - D);

[0126] D=(V 1 -V 2 ) / (2V 1 -V 2 );

[0127] Where D is the duty cycle of the first transistor Q1, and T S is the conduction period of the first transistor Q1.

[0128] According to the above - derived formula for simulation, Figure 5 it is a simulation diagram of the output voltage and duty cycle of a power supply circuit provided by an embodiment of the present invention. Refer to Figure 5 , the abscissa X represents the duty cycle of the first transistor Q1, and the ordinate Y represents the output voltage V 2 of the output terminal of the power supply circuit.

[0129] Among them, the first curve 51 is the simulation curve when V 1 =2.5V, the second curve 52 is the simulation curve when V 1 =12V, and the third curve 53 is the simulation curve when V 1 =25V. It can be seen from Figure 5 that when the duty cycle D of the first transistor Q1 = 0.5, the output voltage V 2 of the output terminal of the power supply circuit = 0. When D < 0.5, V 2 >0. When D > 0.5, V 2 <0. Therefore, by adjusting the duty cycle of the first transistor Q1, the adjustment of the positive voltage, negative voltage, and 0 voltage of the output terminal Vout of the power supply circuit can be achieved.

[0130] When D < 0.5 and the input terminal Vin has different input voltages, the output voltage of the output terminal Vout is a positive voltage. When D > 0.5 and the input terminal Vin has different input voltages, the output voltage of the output terminal Vout is a negative voltage. When D = 0.5 and the input terminal Vin has different input voltages, the output voltage of the output terminal Vout is 0. Therefore, the adjustment of the positive voltage and the negative voltage by the duty cycle is not affected by the input voltage of the input terminal Vin of the power supply circuit.

[0131] In the process of adjusting the voltage by the duty cycle of the present invention, the voltage change process is smooth and there will be no instantaneous rise or fall, thereby realizing seamless adjustment and switching of the output voltage, and having a good adjustment effect.

[0132] Table 1 is a relationship table of an output voltage and a duty cycle provided according to the present invention.

[0133] Table 1

[0134] <![CDATA[V 1 (V)]]> D <![CDATA[V 2 (V)]]> 3.3 0.2 2.48 3.3 0.5 0 3.3 0.7 -4.40 12 0.25 8.00 12 0.5 0 12 0.572 -4.04 22 0.25 14.67 22 0.5 0 22 0.55 -4.89

[0135] Referring to Table 1, the output voltage V of the output terminal of the power supply circuit in Table 1 2 can be calculated by the above formula:

[0136] D = (V 1 - V 2 ) / (2V 1 - V 2 ).

[0137] And this value is the theoretical value. To verify the accuracy of the output voltage, taking D = 0.2 and V 1 = 3.3V as an example for simulation, the obtained simulation diagram is as Figure 6 shown. Referring to Figure 6 , the abscissa represents the time t, and the ordinate represents the output voltage V of the output terminal of the power supply circuit 2 . The output voltage V 2 gradually tends to be stable after a delay of 0.5s, and the output voltage V 2 is about 2.48V, which is consistent with the calculated value.

[0138] Taking D = 0.5 and V 1 = 12V as an example for simulation, the obtained simulation diagram is as Figure 7 shown. Referring to Figure 7 , the output voltage V 2 gradually tends to be stable after a delay of 0.5s, and the output voltage V 2 is about 0V, which is consistent with the calculated value.

[0139] Taking D = 0.55 and V 1Taking = 22V as an example for simulation, the obtained simulation diagram is as follows Figure 8 as shown, referring to Figure 8 , the output voltage V 2 gradually stabilizes after a delay of 0.5s, and the output voltage V 2 is approximately -4.89V, which is consistent with the calculated value.

[0140] Therefore, by adjusting the duty cycle of the control signal of the first transistor Q1, the present invention can achieve the adjustment of the positive voltage, 0 voltage, and negative voltage of the output terminal Vout of the power supply circuit.

[0141] In this embodiment, the first preset threshold is 0.5, which is not a limitation of the present invention. In other embodiments, the first preset threshold can be set to different values according to different transistors.

[0142] Based on the above embodiments, optionally, the first transistor Q1 and the second transistor Q2 are used to conduct or turn off according to their respective duty cycles. Among them, the duty cycle of the second transistor Q2 is complementary to the duty cycle of the first transistor Q1, and the on-off states of the first transistor Q1 and the second transistor Q2 are different. That is, when the first transistor Q1 is turned on, the second transistor Q2 is in the off state; when the first transistor Q1 is turned off, the second transistor Q2 is in the on state.

[0143] Exemplarily, when the duty cycle of the first transistor Q1 is D and the conduction period is T S , the conduction period of the second transistor Q1 is also T S , and the duty cycle is 1 - D.

[0144] Figure 9 is a schematic diagram of the current flow direction in the first stage of a power supply circuit provided by an embodiment of the present invention. Referring to Figure 9 , based on the above embodiments, optionally, the output terminal Vout of the power supply circuit is used to connect a load. Before the load is powered on, the first switch unit 21 is used to control the first energy storage unit 11 and the second energy storage unit 12 to release electrical energy and the third energy storage unit 13 to store electrical energy when it is turned on. The second switch unit 22 is used to control the first energy storage unit 11 and the second energy storage unit 12 to store electrical energy when it is turned on.

[0145] Among them, the load includes sub-pixels 3. Before the load is powered on, it is in the first state, that is, the moment when the first power supply voltage ELVDD is not powered on. Therefore, the first stage is the independent power supply stage of the second power supply voltage ELVSS. In this stage, the first power supply voltage ELVDD is not powered on, the first power supply voltage ELVDD is 0, and the second power supply voltage ELVSS gradually rises from 0 to a stable voltage state.

[0146] In the first stage, the first switching unit 21 and the second switching unit 22 are turned on or off according to the control signal. When the first switching unit 21 is turned on and the second switching unit 22 is turned off, the first energy storage unit 11 starts to release electrical energy, and the current is input to the ground terminal through the first switching unit 21. At the same time, the second energy storage unit 12 also starts to release electrical energy. The energy storage unit 12 can output a current in the form of a triangular wave, which can be equivalent to an alternating current. After the current passes through the third capacitor C3, it flows back to the third energy storage unit 13 through the first switching unit 21, so that the third energy storage unit 13 stores electrical energy.

[0147] When the first switching unit 21 is turned off and the second switching unit 22 is turned on, the input terminal Vin of the power supply circuit charges the second energy storage unit 12 through the second switching unit 22. The second energy storage unit 12 stores electrical energy, and the current of the power supply circuit is output through the output terminal Vout. At the same time, the first energy storage unit 11 also stores electrical energy.

[0148] The power supply circuit provided by the embodiment of the present invention can provide a second power supply voltage greater than 0 to the second power supply line. Before the first moment, the current of the power supply circuit can be output to the output terminal of the power supply circuit through the second end of the second filtering unit. The current output from the output terminal of the power supply circuit is the source function of the power supply circuit. After the power supply of the second power supply voltage is stable, the first power supply voltage is powered on, so that the power-on of the first power supply voltage will not affect the stable power supply of the second power supply voltage.

[0149] Figure 10 It is a schematic diagram of the current flow direction in the second stage of a power supply circuit provided by an embodiment of the present invention. Refer to Figure 10 On the basis of the above embodiments, optionally, when the load is powered on, the first switching unit 21 is used to control the first energy storage unit 11 and the second energy storage unit 12 to store electrical energy when it is turned on. The second switching unit 22 is used to control the first energy storage unit 11 and the second energy storage unit 12 to release electrical energy and the third energy storage unit 13 to store electrical energy when it is turned on.

[0150] Among them, after the load is powered on, it is in the second state, that is, after the second power supply voltage ELVSS is fully established, the second power supply voltage ELVSS is in a stable voltage state. At this time, the first power supply voltage ELVDD of the load can be powered on and the sub-pixel 3 can be powered.

[0151] When the first switching unit 21 is turned on and the second switching unit 22 is turned off, the input terminal Vin of the power supply circuit charges the first energy storage unit 11. The first energy storage unit 11 stores electrical energy, and the current output by the first energy storage unit 11 is input to the ground terminal through the first switching unit 21. At the same time, the second energy storage unit 12 also stores electrical energy. At this time, the current flowing through the sub-pixel 3 in the first power supply line is input to the power supply circuit through the output terminal Vout.

[0152] When the first switching unit 21 is turned off and the second switching unit 22 is turned on, the first energy storage unit 11 starts to release electrical energy and charge the third energy storage unit 13, and the current flows back to the first energy storage unit 11 through the second switching unit 22. At the same time, the second energy storage unit 12 also starts to release electrical energy, and the current is input to the ground terminal through the second switching unit 22 and the second capacitor C2. At this time, the current flowing through the first power line of the sub-pixel 3 remains in the state of being input to the power supply circuit through the output terminal Vout.

[0153] In the embodiment of the present invention, the power supply circuit powers on the second power supply voltage before the first power supply voltage, so that the power supply circuit has a source function and realizes the output of current. When the voltage of the second power supply voltage is stable, the first power supply voltage is powered on. At this time, the current is input to the power supply circuit through the output terminal of the power supply circuit, and the power supply circuit has a sink function. Therefore, the power supply circuit provided by the present invention has both sink and source functions, and the power supply circuit can operate stably when the current is output or input from the output terminal of the power supply circuit, and has high applicability and safety.

[0154] The embodiment of the present invention provides a control method for a power supply circuit. This method can be executed by a display device and can be implemented in the form of software and / or hardware. Figure 11 It is a flowchart of a control method for a power supply circuit provided by an embodiment of the present invention. Refer to Figure 11 , the control method of the power supply circuit includes:

[0155] S110. Before the load is powered on, the energy storage module outputs current through the output terminal of the power supply circuit.

[0156] Among them, in combination with Figure 9 and Figure 11 , before the load is powered on, the first power supply voltage ELVDD is not powered on, and the second power supply voltage ELVSS gradually rises from 0 to a stable voltage state.

[0157] When the first transistor Q1 is turned off and the second transistor Q2 is turned on, the input terminal Vin of the power supply circuit supplies power to the second inductor L2 through the second transistor Q2, and the first inductor L2 stores energy. Because the first inductor L1 and the second inductor L2 are associated with the same-named terminals, the first inductor L1 also stores energy at the same time. At this time, the current of the second inductor L2 can be output through the output terminal Vout of the power supply circuit.

[0158] When the first transistor Q1 is turned on and the second transistor Q2 is turned off, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy. At this time, the current direction of the second inductor L2 remains unchanged and still outputs through the output terminal Vout of the power supply circuit.

[0159] Therefore, before the load is powered on, the energy storage module can output current to the output terminal Vout of the power supply circuit through the second inductor L2, and the power supply circuit has the source function.

[0160] S120. After the load is powered on, the current in the load is input through the output terminal of the power supply circuit.

[0161] Among them, combined with Figure 10 and Figure 11 , after the load is powered on, both the second power supply voltage ELVSS and the first power supply voltage ELVDD are in the powered-on state.

[0162] When the first transistor Q1 is turned on and the second transistor Q2 is turned off, the input terminal Vin of the power supply circuit supplies power to the first inductor L1, and the first inductor L1 stores energy. Due to the homonymous terminal association between the first inductor L1 and the second inductor L2, the second inductor L2 also stores energy at the same time. At this time, the current of the sub-pixel 3 flows into the power supply circuit through the output terminal Vout of the power supply circuit.

[0163] When the first transistor Q1 is turned off and the second transistor Q2 is turned on, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy. At this time, the current flow direction of the output terminal Vout of the power supply circuit remains unchanged, and still flows into the power supply circuit through the output terminal Vout of the power supply circuit, and the power supply circuit has the sink function.

[0164] The power supply circuit provided by the embodiment of the present invention has two functions of sink and source, and has high applicability. And when the second power supply voltage is positive, the power supply mode in which the second power supply voltage precedes the first power supply voltage enables the power supply circuit to power on the first power supply voltage after being in a stable power supply state. The power supply circuit has a good ability to receive current and can maintain stable operation when the current is input from the output terminal of the power supply circuit. The power supply circuit will not be damaged due to the power on of the first power supply voltage, and has high reliability.

[0165] Figure 11 It is a flowchart of a specific implementation method of an S110 provided by an embodiment of the present invention. Refer to Figure 11 , on the basis of the above embodiments, optionally, S110. Before the load is powered on, the energy storage module outputs current through the output terminal of the power supply circuit, including:

[0166] S111. Control the first switch unit to be turned on and the second switch unit to be turned off, so that the first energy storage unit and the second energy storage unit release electrical energy, and the third energy storage unit stores electrical energy.

[0167] Among them, when in the power-on stage of the second power supply voltage, the first power supply voltage is 0. When the first switch unit is turned on and the second switch unit is turned off, the first energy storage unit and the second energy storage unit start to release electrical energy, and the third energy storage unit is charged. At this time, the power supply circuit outputs current through the output terminal, and the power supply circuit has the source function.

[0168] S112. Control the first switch unit to turn off and the second switch unit to turn on, so that the first energy storage unit and the second energy storage unit store electrical energy.

[0169] Among them, when the first switch unit is turned off and the second switch unit is turned on, the input terminal of the power supply circuit charges the second energy storage unit through the second switch unit, the second energy storage unit stores electrical energy, and the first energy storage unit also stores electrical energy at the same time. At this time, the power supply circuit still outputs current through the output terminal, and the power supply circuit has the source function.

[0170] Figure 12 It is a flowchart of a specific implementation method of S120 provided by an embodiment of the present invention. Refer to Figure 12 , on the basis of the above embodiments, optionally, S120. When the load is powered on, the current in the load is input through the output terminal of the power supply circuit, including:

[0171] S121. Control the first switch unit to turn on and the second switch unit to turn off, so that the first energy storage unit and the second energy storage unit store electrical energy.

[0172] Among them, after the first moment, the first power supply voltage is powered on, and at this time the first power supply voltage is higher than the second power supply voltage.

[0173] When the first switch unit is turned on and the second switch unit is turned off, the input terminal of the power supply circuit charges the first energy storage unit, the first energy storage unit stores electrical energy, and the second energy storage unit also stores electrical energy at the same time. At this time, the sub-pixel inputs current to the output terminal of the power supply circuit, and the power supply circuit has the sink function.

[0174] S122. Control the first switch unit to turn off and the second switch unit to turn on, so that the first energy storage unit and the second energy storage unit release electrical energy, and the third energy storage unit stores electrical energy.

[0175] Among them, when the first switch unit is turned off and the second switch unit is turned on, the first energy storage unit and the second energy storage unit start to release electrical energy, and the third energy storage unit is charged. Because the first power supply voltage is higher than the second power supply voltage, the current will start from the first power line and pass through the sub-pixel to input to the output terminal of the power supply circuit. At this time, the sub-pixel inputs current to the output terminal of the power supply circuit, and the power supply circuit has the sink function.

[0176] By providing a first switching unit and a second switching unit, the present invention realizes the charge and discharge control of a first energy storage unit, a second energy storage unit, and a third energy storage unit, and can operate stably when current is output from or input to the output terminal Vout of the power supply circuit, having high applicability.

[0177] Based on the above embodiments, optionally, the control method of the power supply circuit further includes: when the duty cycle of the control terminal signal of the first transistor is greater than a first preset threshold, the energy storage module outputs a negative voltage to the output terminal of the power supply circuit. When the duty cycle of the control terminal signal of the first transistor is equal to the first preset threshold, the energy storage module outputs a zero voltage to the output terminal of the power supply circuit. When the duty cycle of the control terminal signal of the first transistor is less than the first preset threshold, the energy storage module outputs a positive voltage to the output terminal of the power supply circuit.

[0178] Wherein, the first transistor Q1 and the second transistor Q2 are used to conduct or cut off according to the control signal. Different on-off states of the first transistor Q1 and the second transistor Q2 can be used to adjust the charge and discharge states of the first inductor L1, the second inductor L2, and the first capacitor C1, and further adjust the output voltage of the output terminal Vout of the power supply circuit.

[0179] When the second power supply voltage ELVSS is powered on and the first power supply voltage ELVDD is not powered on, if the first transistor Q1 is turned off and the second transistor Q2 is turned on, the second inductor L2 stores energy. Because the first inductor L1 and the second inductor L2 have a common terminal connection, the first inductor L1 stores energy simultaneously. If the first transistor Q2 is turned on and the second transistor Q2 is turned off, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy.

[0180] When both the second power supply voltage ELVSS and the first power supply voltage ELVDD are powered on, if the first transistor Q1 is turned off and the second transistor Q2 is turned on, the first inductor L1 and the second inductor L2 release electrical energy, and the first capacitor C1 stores energy. If the first transistor Q2 is turned on and the second transistor Q2 is turned off, the first inductor L1 and the second inductor L2 store energy.

[0181] An embodiment of the present invention provides a power chip. The chip includes: the power supply circuit provided in any embodiment of the present invention, which has beneficial effects similar to those of the power supply circuit and will not be elaborated here.

[0182] An embodiment of the present invention provides a display device. Figure 14 It is a schematic structural diagram of a display device provided by an embodiment of the present invention. Refer to Figure 14, the device includes: a display panel 6 and a power supply chip 7 provided in any embodiment of the present invention, which has beneficial effects similar to those of the power supply chip and will not be elaborated here. Among them, the first power supply port of the power supply chip 7 is connected to a first power supply line, the second power supply port of the power supply chip 7 is connected to a second power supply line, and the second power supply line can also be connected to the ground port GND of the power supply chip 7. The display panel 6 can be connected with a timing controller 8 (TCON, Timing Controller) for controlling the display panel 6 to display correct and stable images.

[0183] It should be understood that various forms of the processes shown above can be used, steps can be reordered, added or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is made herein.

[0184] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub - combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A power supply circuit, characterized in that: include: An energy storage module connected between the input end and the output end of the power supply circuit; A switch module is connected to the energy storage module. In a first state, the switch module controls the energy storage module to output current through the output end of the power supply circuit; in a second state, the switch module controls the energy storage module to input current through the output end of the power supply circuit.

2. The power supply circuit according to claim 1, characterized in that: The switch module is used to adjust the output voltage of the energy storage module according to the duty cycle of the control signal; wherein, when the duty cycle of the control signal is different, the output voltage of the energy storage module is different.

3. The power supply circuit according to claim 1, characterized in that: The energy storage module comprises: a first energy storage unit, a second energy storage unit and a third energy storage unit; The first end of the first energy storage unit and the input end of the power supply circuit are connected to a first node, the second end of the first energy storage unit and the first end of the third energy storage unit are connected to a second node, the second end of the third energy storage unit and the first end of the second energy storage unit are connected to a third node, and the second end of the second energy storage unit and the output end of the power supply circuit are connected to a fourth node; The first energy storage unit, the second energy storage unit and the third energy storage unit are used to store or release electrical energy; wherein the first energy storage unit and the second energy storage unit store or release electrical energy simultaneously; Preferably, the first energy storage unit includes: a first inductor; the second energy storage unit includes: a first capacitor; the third energy storage unit includes: a second inductor; The first end of the first inductor is connected to the first node, the second end of the first inductor and the first end of the first capacitor are connected to the second node, the second end of the first capacitor and the first end of the second inductor are connected to the third node, and the second end of the second inductor and the output end of the power supply circuit are connected to the fourth node; the first inductor and the second inductor have the same-name ends associated.

4. The power supply circuit according to claim 3, characterized in that: The switch module comprises: a first switch unit and a second switch unit; The first end of the first switch unit and the second end of the first energy storage unit are connected to the second node, and the second end of the first switch unit is grounded; The first end of the second switch unit is connected to the first node, and the second end of the second switch unit and the first end of the second energy storage unit are connected to the third node; Preferably, the output end of the power supply circuit is used to connect a load; Before the load is powered on, the first switch unit is used to control the first energy storage unit and the second energy storage unit to release electric energy, and the third energy storage unit to store electric energy when it is turned on; The second switch unit is used to control the first energy storage unit and the second energy storage unit to store electric energy when being turned on; When the load is powered on, the first switch unit is used to control the first energy storage unit and the second energy storage unit to store electric energy when being turned on; The second switch unit is used to control the first energy storage unit and the second energy storage unit to release electric energy and the third energy storage unit to store electric energy when being turned on; Preferably, the load is in the first state before being powered on; and is in the second state after being powered on; Preferably, the first switch unit includes: a first transistor, and the second switch unit includes a second transistor; the first end of the first transistor and the second end of the first energy storage unit are connected to the second node, and the second end of the first transistor is grounded; the first end of the second transistor and the input end of the power supply circuit are connected to the first node, and the second end of the second transistor and the first end of the second energy storage unit are connected to the third node; When the duty cycle of the control terminal signal of the first transistor is greater than a first preset threshold, the energy storage module outputs a negative voltage to the output terminal of the power supply circuit; When the duty cycle of the control terminal signal of the first transistor is equal to the first preset threshold, the energy storage module outputs zero voltage to the output terminal of the power supply circuit; When the duty cycle of the control terminal signal of the first transistor is less than the first preset threshold, the energy storage module outputs a positive voltage to the output terminal of the power supply circuit; Preferably, the first transistor and the second transistor are used to be turned on or off according to their respective duty cycles; wherein the duty cycle of the second transistor is complementary to the duty cycle of the first transistor; Preferably, the first transistor and the second transistor have different on / off states.

5. The power supply circuit according to claim 3, characterized in that: The power supply circuit further includes: a first filtering unit and a second filtering unit; The first end of the first filter unit and the input end of the power supply circuit are connected to the first node, and the second end of the first filter unit is grounded; the first end of the second filter unit and the output end of the power supply circuit are connected to the fourth node, and the second end of the second filter unit is grounded.

6. A method for controlling a power supply circuit, characterized in that: The power supply circuit comprises: an energy storage module and a switch module; the energy storage module is connected between the input end and the output end of the power supply circuit; the switch module is connected to the energy storage module; The control method of the power supply circuit comprises: Before the load is powered on, the energy storage module outputs current through the output end of the power supply circuit; When the load is powered on, the current in the load is input through the output end of the power supply circuit.

7. The control method of the power supply circuit according to claim 6, characterized in that: Before the load is powered on, the energy storage module outputs current through the output end of the power supply circuit, including: Controlling the first switch unit to be turned on and the second switch unit to be turned off, so that the first energy storage unit and the second energy storage unit release electric energy, and the third energy storage unit stores electric energy; Controlling the first switch unit to turn off and the second switch unit to turn on, so that the first energy storage unit and the second energy storage unit store electrical energy; When the load is powered on, the current in the load is input through the output end of the power supply circuit, including: Controlling the first switch unit to be turned on and the second switch unit to be turned off, so that the first energy storage unit and the second energy storage unit store electrical energy; The first switch unit is controlled to be turned off and the second switch unit is controlled to be turned on, so that the first energy storage unit and the second energy storage unit release electric energy, and the third energy storage unit stores electric energy.

8. The control method of the power supply circuit according to claim 6, characterized in that: The control method of the power supply circuit further includes: When the duty cycle of the control terminal signal of the first transistor is greater than a first preset threshold, the energy storage module outputs a negative voltage to the output terminal of the power supply circuit; When the duty cycle of the control terminal signal of the first transistor is equal to the first preset threshold, the energy storage module outputs zero voltage to the output terminal of the power supply circuit; When the duty cycle of the control terminal signal of the first transistor is less than the first preset threshold, the energy storage module outputs a positive voltage to the output terminal of the power supply circuit.

9. A power chip, characterized in that: include: The power supply circuit according to any one of claims 1 to 5.

10. A display device, characterized in that: include: A display panel and the power chip as claimed in claim 9.

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