Power supply control circuit, power management chip and display module

Abstract

The invention discloses a power supply control circuit, a power management chip and a display module. The power supply control circuit comprises a voltage input end, a first power output end, a second power output end, a voltage conversion module, a voltage division module and a feedback module, the voltage conversion module is used for converting an input voltage of the voltage input end into a first power supply voltage and outputting the first power supply voltage to the first power supply output end; a first end of the voltage division module is electrically connected with a first power supply output end, a voltage division output end of the voltage division module is electrically connected with the second power supply output end, the voltage division module is used for dividing the first power supply voltage into second power supply voltage, and the second power supply voltage is output by the voltage division output end; and the feedback module is used for controlling the output of the voltage conversion module according to the first power supply voltage feedback. According to the invention, the problem of screen lighting abnormity of the display panel when the power supply control circuit is applied to the display panel can be improved.

Description

Technical Field

[0001] The present invention relates to the field of power supply technology, and in particular to a power supply control circuit, a power management chip and a display module. Background Art

[0002] Power supply control circuits have important applications in the field of modern electronic technology. For example, they can provide power for light-emitting elements in display panels.

[0003] However, when the power supply control circuit in the related art supplies power to the display panel, the display panel is prone to abnormal screen dots. Summary of the Invention

[0004] The present invention provides a power supply control circuit, a power management chip and a display module to improve the problem of abnormal screen dots on a display panel when the power supply control circuit is applied to the display panel.

[0005] According to one aspect of the present invention, there is provided a power supply control circuit, the power supply control circuit comprising:

[0006] A voltage input terminal, a first power output terminal, a second power output terminal, a voltage conversion module, a voltage dividing module and a feedback module;

[0007] The voltage conversion module is used to convert the input voltage of the voltage input end into a first power supply voltage and output the first power supply voltage to the first power supply output end;

[0008] The first end of the voltage divider module is electrically connected to the first power output end, and the voltage divider output end of the voltage divider module is electrically connected to the second power output end. The voltage divider module is used to divide the first power voltage into a second power voltage and output it through the voltage divider output end;

[0009] The feedback module is used to control the output of the voltage conversion module according to the first power supply voltage feedback.

[0010] Optionally, the power supply control circuit further includes an enabling switch module, and the voltage-dividing output terminal is electrically connected to the second power supply output terminal via the enabling switch module; the enabling switch module is configured to be turned on when its control terminal is enabled;

[0011] Preferably, the first end of the enabling switch module is electrically connected to the voltage divider output end, the second end of the enabling switch module is electrically connected to the second power supply output end, and the control end of the enabling switch module is used to receive an enabling signal;

[0012] Preferably, the first power output terminal is used to be electrically connected to the first electrode of the light-emitting element in the display panel;

[0013] Preferably, the second power output terminal is used to be electrically connected to the second electrode of the light-emitting element in the display panel.

[0014] Optionally, the power supply control circuit further includes a selection module, and the enabling switch module is electrically connected to the second power supply output terminal through the selection module; wherein a first terminal of the selection module is electrically connected to the enabling switch module, a second terminal of the selection module is electrically connected to a ground terminal of the power supply control circuit, and a common terminal of the selection module is electrically connected to the second power supply output terminal;

[0015] Preferably, the first end of the selection module is electrically connected to the second end of the enabling switch module.

[0016] Optionally, the voltage divider module includes a first variable resistor unit and a second variable resistor unit, wherein a first end of the first variable resistor unit is electrically connected to the first power supply output terminal, a second end of the first variable resistor unit is electrically connected to the voltage divider output terminal, a first end of the second variable resistor unit is electrically connected to the voltage divider output terminal, and a second end of the second variable resistor unit is electrically connected to the ground terminal;

[0017] Preferably, the power supply control circuit further includes a communication unit, a calculation unit, a first resistance adjustment unit, and a second resistance adjustment unit; the communication unit is used to receive a resistance adjustment signal, the input end of the calculation unit is electrically connected to the communication unit, and the calculation unit is used to generate a first control signal and a second control signal based on the resistance adjustment signal;

[0018] The first resistance adjusting unit is electrically connected to the output terminal of the calculation unit and the control terminal of the first variable resistance unit, and the first resistance adjusting unit is used to adjust the resistance of the first variable resistance unit according to the first control signal;

[0019] The second resistance adjusting unit is electrically connected to the output end of the calculation unit and the control end of the second variable resistance unit, and the second resistance adjusting unit is used to adjust the resistance of the second variable resistance unit according to the second control signal.

[0020] Optionally, the feedback input end of the feedback module is electrically connected to the voltage divider output end, and the output end of the feedback module is electrically connected to the voltage conversion module; the feedback module is used to compare the divided voltage at the voltage divider output end with a reference voltage, generate a corresponding pulse width control signal according to the comparison result, and output the pulse width control signal to the voltage conversion module.

[0021] Optionally, the feedback module includes: an error amplification unit, a zero-pole compensation unit, a comparison unit and a sampling unit;

[0022] The first input terminal of the error amplifying unit is electrically connected to the feedback input terminal, the second input terminal of the error amplifying unit is connected to the reference voltage, and the output terminal of the error amplifying unit is electrically connected to the first input terminal of the comparison unit;

[0023] The pole-zero compensation unit is electrically connected to the first input terminal of the error amplification unit and the output terminal of the error amplification unit, and the pole-zero compensation unit is used to compensate for the zeros and poles of the feedback module;

[0024] The sampling unit is used to sample the current of the voltage input terminal and generate a sawtooth wave, and the second input terminal of the comparison unit is connected to the sawtooth wave; the output terminal of the comparison unit is electrically connected to the voltage conversion module;

[0025] Preferably, the pole-zero compensation unit comprises a type III compensator;

[0026] Preferably, the feedback module further includes a latch unit, and the output end of the comparison unit is electrically connected to the voltage conversion module through the latch unit.

[0027] Optionally, the voltage conversion module includes a first transistor, a diode, an inductor, and a first capacitor, wherein a first end of the first transistor is electrically connected to the voltage input end, a second end of the first transistor is electrically connected to a first end of the inductor, and a second end of the inductor is electrically connected to the first power output end;

[0028] The cathode of the diode is electrically connected to the second end of the first transistor, and the anode of the diode is electrically connected to the reference ground terminal of the voltage conversion module;

[0029] The first end of the first capacitor is electrically connected to the second end of the inductor, and the second end of the first capacitor is electrically connected to the reference ground end.

[0030] Optionally, the power supply control circuit further includes a processing module, and the processing module is used to configure parameters of the power supply control circuit;

[0031] Preferably, the parameters of the power supply control circuit include parameters of at least one of the voltage divider module and the feedback module;

[0032] Preferably, the power supply control circuit further includes a storage module, in which a correspondence between the parameters of the power supply control circuit and the load current of the power supply control circuit is stored; the processing module is used to call the parameters of the voltage divider module in the storage module to configure the power supply control circuit according to the load current of the power supply control module;

[0033] Preferably, the corresponding relationship between the parameters of the power supply control circuit and the load current of the power supply control circuit is obtained by the following method:

[0034] Determining a maximum current, a minimum current, a first power supply voltage, and a second power supply voltage corresponding to a load of the power supply control circuit;

[0035] The current to be calculated is obtained by traversing at preset intervals within the range of the minimum value of the current and the maximum value of the current, and the parameters of the power supply control circuit corresponding to the current to be calculated are calculated according to the current to be calculated, the first power supply voltage and the second power supply voltage.

[0036] According to another aspect of the present invention, a power management chip is provided, wherein the power management chip includes the power supply control circuit as described above.

[0037] According to another aspect of the present invention, a display module is provided, comprising the power management chip and a display panel as described above;

[0038] The display panel includes a plurality of light emitting elements, the first power output end is electrically connected to the first ends of the light emitting elements, and the second power output end is electrically connected to the second ends of the light emitting elements.

[0039] The technical solution of the embodiment of the present invention adopts a power supply control circuit including a voltage input terminal, a first power supply output terminal, a second power supply output terminal, a voltage conversion module, a voltage divider module, and a feedback module. The voltage conversion module is used to convert the input voltage of the voltage input terminal into a first power supply voltage and output it to the first power supply output terminal. The first terminal of the voltage divider module is electrically connected to the first power supply output terminal, and the voltage divider output terminal of the voltage divider module is electrically connected to the second power supply output terminal. The voltage divider module is used to divide the first power supply voltage into a second power supply voltage, which is output from the voltage divider output terminal. The feedback module is used to feedback control the output of the voltage conversion module based on the first power supply voltage. The voltage divider module divides the first power supply voltage output from the first power supply output terminal to generate a second power supply voltage, which is output from the second power supply output terminal. Therefore, a single power supply control circuit can generate two power supply voltages greater than zero. The first power supply output terminal outputs a source current, while the second power supply output terminal has a sink current. The current output from the first power supply output terminal can flow to the second power supply output terminal, that is, the second power supply output terminal has the ability to sink current, thereby avoiding the problem of abnormal dot screen when the power supply control circuit is applied to a display panel.

[0040] 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 intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 A schematic diagram of the circuit structure of a power supply control circuit provided in an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of a circuit structure in which a power supply control circuit is connected to a display panel according to an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of the circuit structure of another power supply control circuit provided in an embodiment of the present invention;

[0045] Figure 4 A schematic diagram of the circuit structure of another power supply control circuit provided in an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of the circuit structure of another power supply control circuit provided in an embodiment of the present invention;

[0047] Figure 6 A schematic diagram of the circuit structure of another power supply control circuit provided in an embodiment of the present invention;

[0048] Figure 7 A schematic diagram of the circuit structure of a type III compensator provided by an embodiment of the present invention;

[0049] Figure 8 A flowchart of a method for obtaining a corresponding relationship between parameters of a power supply control circuit and a load current of the power supply control circuit provided by an embodiment of the present invention;

[0050] Figure 9 A schematic structural diagram of a display module provided by an embodiment of the present invention;

[0051] Figure 10 A schematic structural diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0053] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0054] When the power supply control circuit in the related art is applied to the display panel, the display panel has the problem of abnormal screen dots. After a lot of research, the inventor found that the reason for this technical problem is that for the display panel using oxide transistors, it is necessary to require that the voltages input to the first power input terminal and the second power input terminal of the pixel circuit in the display panel are both positive voltages. However, the power supply control circuit in the related art, after connecting the first power input terminal and the second power input terminal of the pixel circuit, the first power input terminal and the second power input terminal are both positive voltages, and relative to the ground terminal of the display panel and / or the ground terminal of the power supply control circuit, the current direction between the first power input terminal and the ground terminal is from the first power input terminal to the ground terminal; the current direction between the second power input terminal and the ground terminal is from the second power input terminal to the ground terminal. In other words, a current loop cannot be formed between the first power input terminal and the second power input terminal, resulting in the problem of abnormal screen dots.

[0055] In view of the above technical problems, the present invention proposes the following solutions:

[0056] Figure 1 A schematic diagram of a power supply control circuit according to an embodiment of the present invention is provided. Figure 1 The power supply control circuit includes: a voltage input terminal Vin, a first power output terminal ELVDD, a second power output terminal ELVSS, a voltage conversion module 11, a voltage divider module 12, and a feedback module 13; the voltage conversion module 13 is used to convert the voltage input from the voltage input terminal Vin into a first power voltage and output it to the first power output terminal ELVDD; the first terminal of the voltage divider module 12 is electrically connected to the first power output terminal ELVDD, and the voltage divider output terminal of the voltage divider module 12 is electrically connected to the second power output terminal ELVSS. The voltage divider module 12 is used to divide the first power voltage into a second power voltage and output it from the voltage divider output terminal; the feedback module 13 is used to control the output of the voltage conversion module 11 based on the first power voltage feedback.

[0057] Specifically, the power supply control circuit can be applied to a display panel to provide a power supply signal to a light-emitting element in the display panel. More specifically, the pixel circuit in the display panel is a pixel circuit including an oxide transistor, and the first power supply output terminal ELVDD and the second power supply output terminal ELVSS are respectively used to provide a first power supply signal and a second power supply signal to the pixel circuit. The first power supply signal is greater than the second power supply signal.

[0058] The voltage input terminal Vin can be connected to an external power source, such as a battery. The voltage conversion module 11 can convert the DC signal input from the external power source into a power supply voltage suitable for the pixel circuit in the display panel, namely, a first power supply voltage, and output it to the pixel circuit. The voltage conversion module 11 can be, for example, a step-up converter or a step-down converter that converts the input voltage into the first power supply voltage. In other embodiments, the voltage conversion module 11 can also convert the input voltage into other voltages required by the display panel, such as an initialization voltage.

[0059] Feedback module 13 can control the output of voltage conversion module 11 based on the first power supply voltage feedback, thereby ensuring that voltage conversion module 11 stably outputs the first power supply voltage. In other words, when the first power supply voltage fluctuates, feedback module 13 can promptly adjust the parameters of voltage conversion module 11 to stabilize the first power supply voltage.

[0060] In this embodiment, the power supply control circuit further includes a voltage divider module 12, which divides the first power supply voltage on the first power supply output terminal ELVDD and outputs a second power supply voltage from the voltage divider output terminal, wherein the second power supply voltage is less than the first power supply voltage. The first power supply voltage and the second power supply voltage are both greater than zero. Therefore, a power supply control circuit can be used to provide two power supply voltages greater than zero for a pixel circuit including an oxide transistor, thereby reducing the area of ​​the power supply control circuit and reducing costs. The current output from the first power supply output terminal ELVDD is a source current. In addition, if Figure 2 As shown, Figure 2 Schematic diagram of a circuit structure of a power supply control circuit connected to a display panel according to an embodiment of the present invention. Since the second power supply voltage is output after the first power supply voltage is divided, after the first power supply output terminal ELVDD and the second power supply output terminal ELVSS are connected to the display panel 20, the current direction is as follows: Figure 2As shown by the arrow in the middle. That is, the current flows from the first power output terminal ELVDD into the display panel, and flows from the display panel to the second power output terminal ELVSS, and finally flows from the second power output terminal ELVSS to the inside of the power supply control circuit, forming a closed loop through the ground terminal. In other words, in the power supply control circuit of this embodiment, the second power output terminal ELVSS can not only output a positive power supply voltage, but also has the ability to sink current. The current output by the first power output terminal ELVDD can flow into the second power output terminal ELVSS to form a current loop, thereby improving the point screen abnormality problem caused by the power supply control circuit being applied to the display panel.

[0061] The technical solution of this embodiment adopts a power supply control circuit including a voltage input terminal, a first power supply output terminal, a second power supply output terminal, a voltage conversion module, a voltage divider module, and a feedback module. The voltage conversion module is used to convert the input voltage of the voltage input terminal into a first power supply voltage and output it to the first power supply output terminal. The first terminal of the voltage divider module is electrically connected to the first power supply output terminal, and the voltage divider output terminal of the voltage divider module is electrically connected to the second power supply output terminal. The voltage divider module is used to divide the first power supply voltage into a second power supply voltage, which is output from the voltage divider output terminal. The feedback module is used to feedback control the output of the voltage conversion module based on the first power supply voltage. The voltage divider module divides the first power supply voltage output from the first power supply output terminal to generate a second power supply voltage, which is output from the second power supply output terminal. Therefore, a single power supply control circuit can generate two power supply voltages greater than zero. The first power supply output terminal outputs a source current, while the second power supply output terminal has a sink current. The current output from the first power supply output terminal can flow to the second power supply output terminal, that is, the second power supply output terminal has the ability to sink current, thereby avoiding the problem of abnormal dot screen when the power supply control circuit is applied to a display panel.

[0062] Optionally, Figure 3 A schematic diagram of a circuit structure of another power supply control circuit provided in an embodiment of the present invention is provided. Figure 3 The power supply control circuit further includes an enabling switch module 14 , through which the voltage-dividing output terminal is electrically connected to the second power supply output terminal ELVDD; the enabling switch module 14 is configured to be turned on when its control terminal is enabled.

[0063] Specifically, if Figure 3As shown, the first end of the enable switch module 14 is electrically connected to the voltage divider output terminal, the second end of the enable switch module 14 is electrically connected to the second power supply output terminal ELVSS, and the control end of the enable switch module 14 is electrically connected to the enable terminal ELVDD_EN of the power supply control circuit. The enable terminal ELVDD_EN of the power supply control circuit is used to input an enable signal. When the enable terminal ELVDD_EN is enabled, the first and second ends of the enable switch module 14 are conductive, thereby electrically connecting the voltage divider output terminal of the voltage divider module 12 to the second power supply output terminal ELVSS. At this time, the power supply control circuit can output the second power supply voltage from the second power supply output terminal ELVSS. When the enable terminal ELVDD_EN is not enabled, the enable switch module 14 is turned off. At this time, the path between the voltage divider output terminal of the voltage divider module 12 and the second power supply output terminal ELVSS is cut off, and the power supply control circuit cannot output the second power supply voltage from the second power supply output terminal ELVSS. In this embodiment, by providing an enable switch module 14, it is possible to selectively control whether the second power output terminal ELVSS of the power supply control circuit outputs the second power supply voltage, thereby improving the flexibility of the power supply control circuit. For example, in some embodiments, the first power signal required by the pixel circuit is a voltage greater than zero, and the second power signal is a voltage less than zero. In this case, two power supply control circuits can provide power signals to the pixel circuit. The power supply control circuit can control the enable switch module 14 to be disabled, thereby preventing the second power output terminal ELVSS from outputting.

[0064] Optionally, Figure 4 A schematic diagram of a circuit structure of another power supply control circuit provided in an embodiment of the present invention is provided. Figure 4 The power supply control circuit further includes a selection module 15, through which the enabling switch module 14 is electrically connected to the second power supply output terminal ELVSS; wherein a first end of the selection module 15 is electrically connected to the enabling switch module 14, a second end of the selection module 15 is electrically connected to the ground terminal of the power supply control circuit, and a common end of the selection module 15 is electrically connected to the second power supply output terminal ELVSS.

[0065] Specifically, the first end of the selection module 15 is electrically connected to the second end of the enable switch module 14. The selection module 15 is used to connect its first end and its common end, or connect its second end and its common end, according to the signal of its control end. When the first end of the selection module 15 and its common end are connected, the second power output end ELVSS can provide a second power signal greater than zero for the pixel circuit. When the second end of the selection module 15 and its common end are connected, the second power output end ELVSS can provide a second power signal equal to zero for the pixel circuit. By setting the selection module 15, the power supply control circuit can provide two different second power signals for the pixel circuit, and the compatibility of the power supply control circuit can be further improved.

[0066] Optionally, Figure 5 A schematic diagram of a circuit structure of another power supply control circuit provided in an embodiment of the present invention is provided. Figure 5 The voltage divider module 12 includes a first variable resistor unit R1 and a second variable resistor unit R2; a first end of the first variable resistor unit R1 is electrically connected to the first power output terminal ELVDD, and a second end of the first variable resistor unit R1 is electrically connected to the voltage divider output terminal; a first end of the second variable resistor unit R2 is electrically connected to the voltage divider output terminal, and a second end of the second variable resistor unit R2 is electrically connected to the ground terminal.

[0067] Specifically, the voltage divider module 12 utilizes the voltage dividing effect of the first variable resistor unit R1 and the second variable resistor unit R2 to divide the first power supply voltage and output it. The function of the voltage divider module 12 can be realized by two variable resistor units, the circuit structure is simple, and it is easier to implement. In addition, the first power supply voltage and the second power supply voltage required by the pixel circuit may be adjusted as needed. The proportional relationship between the first power supply voltage and the second power supply voltage may be different, and the required second power supply voltage can be obtained by adjusting at least one of the first variable resistor unit R1 and the second variable resistor unit R2. When the load current of the power supply control circuit is different, the first variable resistor unit R1 and the second variable resistor unit R2 also need to be adjusted to match the load current. For example, when the power supply control circuit is applied to the display panel, the values ​​of the first variable resistor R1 and the second variable resistor R2 are determined according to the expected value of the first power supply voltage (expressed as ELVDD1), the expected value of the second power supply voltage (expressed as ELVSS1) and the current of the pixel circuit (expressed as EL). Among them, R1 = Rall - R2. More specifically, the maximum and minimum values ​​of the pixel circuit's current can be first obtained. The pixel circuit's current is then divided into several parts between the maximum and minimum values. Each pixel circuit's current corresponds to a value of the first variable resistor R1 and a value of the second variable resistor R2. Once the pixel circuit's current is determined, the values ​​of the first variable resistor R1 and the second variable resistor R2 can be determined. It will be understood that the pixel circuit's current corresponds to the brightness of the light-emitting element in the pixel circuit.

[0068] Optionally, Figure 6 A schematic diagram of a circuit structure of another power supply control circuit provided in an embodiment of the present invention is provided. Figure 6The power supply control circuit further includes a communication unit 16, a calculation unit 17, a first resistance adjustment unit 18, and a second resistance adjustment unit 19; the communication unit 16 is used to receive a resistance adjustment signal, the input end of the calculation unit 17 is electrically connected to the communication unit 16, and the calculation unit 17 is used to generate a first control signal and a second control signal based on the resistance adjustment signal; the first resistance adjustment unit 18 is electrically connected to the output end of the calculation unit 17 and the control end of the first variable resistance unit R1, and the first resistance adjustment unit 18 is used to adjust the resistance of the first variable resistance unit R1 according to the first control signal; the second resistance adjustment unit 19 is electrically connected to the output end of the calculation unit 17 and the control end of the second variable resistance unit R2, and the second resistance adjustment unit 19 is used to adjust the resistance of the second variable resistance unit R2 according to the second control signal.

[0069] Specifically, the communication unit 16 is, for example, an IIC communication unit, capable of receiving IIC communication signals, that is, receiving resistance adjustment signals. The resistance adjustment signal can be output by, for example, a driving circuit of a mainboard or display panel. The calculation unit 17 calculates the resistance values ​​of the first variable resistor unit R1 and the second variable resistor unit R2 based on the resistance adjustment signal, and adjusts the resistance value of the first variable resistor R1 via the first resistance adjustment unit 18, and adjusts the resistance value of the second variable resistor unit R2 via the second resistance adjustment voltage 19. The first resistance adjustment unit 18 and the first variable resistor unit R1 can constitute a digital potentiometer, and the first resistance adjustment unit 18 can be composed of, for example, multiple switches. The first variable resistor unit R1 is composed of multiple resistors connected in series and / or in parallel, and its effective resistance value is changed under the control of the first resistance adjustment unit 18. The specific structure of the digital potentiometer is well known to those skilled in the art and will not be repeated here. Similarly, the second resistance adjustment unit 19 and the second variable resistor unit R2 can constitute a digital potentiometer, and the second resistance adjustment unit 19 can be composed of, for example, multiple switches. The second variable resistance unit R2 is composed of a plurality of resistors connected in series and / or in parallel, and is controlled by the second resistance adjustment unit 19 to change its effective resistance value.

[0070] Optionally, continue to refer to Figure 6 The feedback module 13 includes: an error amplification unit DA, a zero-pole compensation unit 131, a comparison unit 132, and a sampling unit; a first input terminal of the error amplification unit EA is electrically connected to the feedback input terminal, a second input terminal of the error amplification unit EA is connected to the reference voltage Vref, and an output terminal of the error amplification unit EA is electrically connected to the first input terminal of the comparison unit 132; a zero-pole compensation unit 131 is electrically connected to the first input terminal and the output terminal of the error amplification unit EA, and is used to compensate for the zeros and poles of the feedback module 13;

[0071] The sampling unit is used to sample the input current of the voltage input terminal Vin and generate a sawtooth wave; the second input terminal of the comparison unit 132 is connected to the sawtooth wave; and the output terminal of the comparison unit 132 is electrically connected to the voltage conversion module 11 .

[0072] Specifically, the feedback module 13 is used to sample the voltage output from the first power supply output terminal ELVDD and then provide feedback control to the voltage conversion module 11. In this embodiment, the voltage divider module 12 can be used as the voltage sampling unit of the feedback module 13, eliminating the need for an additional voltage sampling unit for the feedback module 13. This can further reduce the number of components in the power supply control circuit and help save the required area of ​​the power supply control circuit. In this embodiment, the signal input to the feedback input terminal of the feedback module 13 is differentially amplified with the second power supply voltage. The second power supply voltage is differentially amplified with a reference voltage to generate a comparison signal. In addition, the zero-pole compensation unit 131 can compensate for the zeros and poles of the feedback module loop, improving the stability of the power supply control circuit. The sampling unit includes a current sampler 133 and a gain unit 134. The current sampler 133 is used to sample the current at the voltage input terminal Vin and generate a sawtooth waveform after passing through the gain module 134. This sawtooth waveform is output to the second input terminal of the comparison unit 132. The comparison unit 132 compares the comparison signal output by the error amplification unit EA with the sawtooth wave to generate a pulse width modulation signal. The pulse width modulation signal can be used to control the voltage conversion module 11 .

[0073] Optionally, continue to refer to Figure 6 The feedback module 13 further includes a latch unit 135 , and the output end of the comparison unit 132 is electrically connected to the voltage conversion module 11 through the latch unit 135 .

[0074] Specifically, when the output state of the comparison unit 132 is critical, repetition is likely to occur. By providing the latch unit 135, the voltage conversion module 11 is controlled cycle by cycle, thereby preventing the voltage conversion module 11 from experiencing an unstable state. For example, the latch unit 135 may be an RS trigger.

[0075] Optionally, in some embodiments, the feedback module 13 , the communication unit 16 , the calculation unit 17 , the first resistance adjustment unit 18 , and the second resistance adjustment unit 19 may be integrated into a power controller.

[0076] Optionally, Figure 7 A schematic diagram of the circuit structure of a type III compensator provided by an embodiment of the present invention, referring to Figure 6 and Figure 7In this embodiment, the voltage divider module 12, the zero-pole compensation unit 131, and the error amplifier unit EA constitute a type III compensator. Specifically, the type III compensator can compensate for three poles and two zeros, has a high phase gain, and can improve the gain margin and phase margin of the power supply control circuit.

[0077] Optionally, continue to refer to Figure 6 The voltage conversion module 11 includes a first transistor M1, a diode D, an inductor L and a first capacitor C1; the first end of the first transistor M1 is electrically connected to the voltage input terminal Vin, the second end of the first transistor M1 is electrically connected to the first end of the inductor L, and the second end of the inductor L is electrically connected to the first power supply output terminal ELVDD; the cathode of the diode D is electrically connected to the second end of the first transistor M1, and the anode of the diode D is electrically connected to the reference ground terminal of the voltage conversion module 11; the first end of the first capacitor C1 is electrically connected to the second end of the inductor L, and the second end of the first capacitor C1 is electrically connected to the reference ground terminal.

[0078] Specifically, the control terminal of the first transistor M1 serves as the control terminal of the voltage conversion module 11 and is used to receive the pulse width modulation signal. The control terminal of the first transistor M1 is electrically connected to the Q terminal of the latch unit 135. Alternatively, when the feedback module 13 does not include the latch unit 135, the control terminal of the first transistor M1 is electrically connected to the output terminal of the comparison unit 132. The specific operating principle of the voltage conversion module 11 is well known to those skilled in the art and will not be described in detail here. Of course, in other embodiments, the voltage conversion module 11 can also have other structures.

[0079] For example, refer to Figure 7 The zero-pole compensation unit 131 includes a second capacitor C2, a third capacitor C3, a fifth capacitor C5, a third resistor R3, and a fourth resistor R4. The first end of the fifth capacitor C5 is electrically connected to the first power supply output terminal ELVDD, the second end of the fifth capacitor C5 is electrically connected to the first end of the third resistor R3, and the second end of the third resistor R3 is electrically connected to the first input terminal of the error amplifier unit EA. The first end of the second capacitor C2 is electrically connected to the output terminal of the error amplifier unit EA, and the second end of the second capacitor C2 is electrically connected to the first input terminal of the error amplifier unit EA. The first end of the third capacitor C3 is electrically connected to the output terminal of the error amplifier unit EA, the second end of the third capacitor C3 is electrically connected to the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is electrically connected to the first input terminal of the error amplifier unit EA.

[0080] It should be noted that the zero-pole compensation unit 131 may also be other types of compensation circuits.

[0081] Optionally, refer to Figure 6The enabling switch module 14 includes a second transistor M2, the first end of the second transistor M2 serves as the first end of the enabling switch module 14, the second end of the second transistor M2 serves as the second end of the enabling switch module M2, and the control end of the second transistor M2 serves as the control end of the enabling switch module M2.

[0082] Optionally, continue to refer to Figure 6 The selection module 15 includes a two-way selector K2, a first end of the two-way selector K2 serves as a first end of the selection module 15, a second end of the two-way selector K2 serves as a second end of the selection module 15, and a common end of the two-way selector K2 serves as a common end of the selection module 15.

[0083] Optionally, continue to refer to Figure 6 The power supply control circuit further includes a sixth capacitor C6, a first end of the sixth capacitor C6 is electrically connected to the first power output terminal ELVDD, a second end of the sixth capacitor C6 is grounded, and the sixth capacitor C6 is used to filter the output signal of the first power output terminal ELVDD.

[0084] Optionally, continue to refer to Figure 6 The power supply control circuit further includes a seventh capacitor C7, a first end of the seventh capacitor C7 is electrically connected to the second power output terminal ELVSS, a second end of the seventh capacitor C7 is grounded, and the seventh capacitor C7 is used to filter the output signal of the second power output terminal ELVSS.

[0085] Optionally, the power supply control circuit further includes a processing module, and the processing module is used to configure parameters of the power supply control circuit.

[0086] Specifically, the parameters of the power supply control circuit include parameters of at least one of the voltage divider module 12 and the feedback module 13. The processing module is, for example, a DSP. The power supply control circuit may further include a storage module that stores a correspondence between the power supply control circuit parameters and the load current of the power supply control circuit. The processing module is configured to retrieve the power supply control circuit parameters from the storage module based on the load current of the power supply control circuit, thereby improving response speed.

[0087] Optionally, the storage module stores the corresponding relationship between the parameters of the voltage divider module 12 and the load current of the power supply control circuit; the processing module is used to call the parameters of the voltage divider module in the storage module according to the load current of the power supply control module to configure the voltage divider module. More specifically, the load current of the power supply control circuit can be the current of the pixel circuit in the display panel, and the parameters of the voltage divider module are the resistances of the first adjustable resistor R1 and the second adjustable resistor R2 in the voltage divider module. In this embodiment, for each load current of the power supply control circuit, the corresponding parameters of the voltage divider module are pre-stored in the storage module. After the load current of the power supply control circuit is determined, the relevant parameters stored in the storage module can be directly called, thereby improving the response speed of the power supply control circuit.

[0088] In some embodiments, optionally, the storage module stores a correspondence between the parameters of the feedback module and the load current of the power supply control circuit; the processing module is used to call the parameters of the feedback module in the storage module according to the load current of the power supply control circuit to configure the feedback module. The parameters of the feedback module specifically include the parameters of each component in the zero-pole compensation unit. In this embodiment, the parameters of each component in the zero-pole compensation unit are adjustable. Similar to the adjustment of the voltage divider module, in this embodiment, for each load current of the power supply control circuit, the storage module pre-stores the corresponding feedback module parameters. After determining the load current of the power supply control circuit, the relevant parameters stored in the storage module can be directly called, thereby improving the response speed of the power supply control circuit.

[0089] Optionally, Figure 8 A flowchart of a method for obtaining a corresponding relationship between a parameter of a power supply control circuit and a load current of the power supply control circuit provided by an embodiment of the present invention, with reference to Figure 8 The method for obtaining the corresponding relationship includes:

[0090] Step S110, determining a maximum current, a minimum current, a first power supply voltage, and a second power supply voltage corresponding to a load of the power supply control circuit;

[0091] Specifically, the load is, for example, a display panel. The first power supply voltage is also the first power supply signal required by the pixel circuit, and the second power supply voltage is also the second power supply signal required by the pixel circuit. The maximum current is, for example, the load current corresponding to when all pixel circuits in the display panel are at the maximum grayscale. The minimum current is, for example, the load current corresponding to when all pixel circuits in the display panel are at the minimum grayscale.

[0092] In step S120 , the current to be calculated is acquired at preset intervals within the range between the minimum current and the maximum current, and parameters of the power supply control circuit corresponding to the current to be calculated are calculated according to the current to be calculated, the first power supply voltage, and the second power supply voltage.

[0093] Specifically, for the parameters of the storage module, the above-mentioned R1 = Rall - R2, where EL is the current to be calculated in this embodiment. EL takes values ​​at preset intervals between the minimum and maximum values ​​of the current. The maximum value of EL is the maximum value of the current, and the minimum value of EL is the minimum value of the current.

[0094] The parameters of the feedback module, that is, the parameters of the zero-pole compensation unit, can be calculated through the transfer function of the feedback module and the zero-pole. For example, for the type III compensator, its transfer function is Thus, the relationship between zero poles and compensation parameters can be obtained: Among them, w z1 and w z2 is zero point, w p0 , w p1 and w p2 Based on the inferred zeros and poles and the above formula, the relevant parameters of the feedback module can be calculated.

[0095] The present invention further provides a power management chip, which includes the power supply control circuit provided by any embodiment of the present invention. Since the power management chip provided by an embodiment of the present invention includes the power supply control circuit provided by any embodiment of the present invention, it also has the same beneficial effects, which will not be described in detail here.

[0096] The present invention also provides a display module, such as Figure 9 As shown, Figure 9 This is a schematic diagram of the structure of a display module provided in an embodiment of the present invention. The display module includes a power management chip 30 and a display panel 20. The display panel includes multiple light-emitting elements (not shown). A first power output terminal ELVDD is electrically connected to the first terminals of the light-emitting elements, and a second power output terminal ELVSS is electrically connected to the second terminals of the light-emitting elements.

[0097] Specifically, the first end of the light emitting element is, for example, an anode, and the second end is, for example, a cathode. The display module provided by the embodiment of the present invention includes the power supply control circuit provided by the embodiment of the present invention, and thus has the same beneficial effects, which will not be described in detail here.

[0098] The present invention also provides a display device, such as Figure 10 As shown, Figure 10This is a schematic diagram of the structure of a display device provided in an embodiment of the present invention. The display device includes the display module provided in any embodiment of the present invention. The display device can be a mobile phone, tablet computer, MP3 player, MP4 player, smart watch, smart helmet, or other wearable device. Because it includes the display module provided in any embodiment of the present invention, it also has the same beneficial effects, and will not be described in detail here.

[0099] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0100] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A power supply control circuit, characterized in that: The power supply control circuit includes: A voltage input terminal, a first power output terminal, a second power output terminal, a voltage conversion module, a voltage dividing module and a feedback module; The voltage conversion module is used to convert the input voltage of the voltage input end into a first power supply voltage and output the first power supply voltage to the first power supply output end; The first end of the voltage divider module is electrically connected to the first power output end, and the voltage divider output end of the voltage divider module is electrically connected to the second power output end. The voltage divider module is used to divide the first power voltage into a second power voltage and output it through the voltage divider output end; The feedback module is used to control the output of the voltage conversion module according to the first power supply voltage feedback; The power supply control circuit further includes an enabling switch module, through which the voltage-dividing output terminal is electrically connected to the second power supply output terminal; the enabling switch module is configured to be turned on when its control terminal is enabled.

2. The power supply control circuit according to claim 1, characterized in that: The first end of the enabling switch module is electrically connected to the voltage divider output end, the second end of the enabling switch module is electrically connected to the second power supply output end, and the control end of the enabling switch module is used to receive an enabling signal; Preferably, the first power output terminal is used to be electrically connected to the first electrode of the light-emitting element in the display panel; Preferably, the second power output terminal is used to be electrically connected to the second electrode of the light-emitting element in the display panel.

3. The power supply control circuit according to claim 2, characterized in that: The power supply control circuit further includes a selection module, and the enabling switch module is electrically connected to the second power supply output terminal through the selection module; wherein a first terminal of the selection module is electrically connected to the enabling switch module, a second terminal of the selection module is electrically connected to the ground terminal of the power supply control circuit, and a common terminal of the selection module is electrically connected to the second power supply output terminal; Preferably, the first end of the selection module is electrically connected to the second end of the enabling switch module.

4. The power supply control circuit according to claim 1, wherein: The voltage divider module includes a first variable resistor unit and a second variable resistor unit, wherein the first end of the first variable resistor unit is electrically connected to the first power supply output end, the second end of the first variable resistor unit is electrically connected to the voltage divider output end, the first end of the second variable resistor unit is electrically connected to the voltage divider output end, and the second end of the second variable resistor unit is electrically connected to the ground end; Preferably, the power supply control circuit further includes a communication unit, a calculation unit, a first resistance adjustment unit, and a second resistance adjustment unit; the communication unit is used to receive a resistance adjustment signal, the input end of the calculation unit is electrically connected to the communication unit, and the calculation unit is used to generate a first control signal and a second control signal based on the resistance adjustment signal; The first resistance adjusting unit is electrically connected to the output terminal of the calculation unit and the control terminal of the first variable resistance unit, and the first resistance adjusting unit is used to adjust the resistance of the first variable resistance unit according to the first control signal; The second resistance adjusting unit is electrically connected to the output end of the calculation unit and the control end of the second variable resistance unit, and the second resistance adjusting unit is used to adjust the resistance of the second variable resistance unit according to the second control signal.

5. The power supply control circuit according to claim 1, wherein: The feedback input end of the feedback module is electrically connected to the voltage divider output end, and the output end of the feedback module is electrically connected to the voltage conversion module; the feedback module is used to compare the divided voltage at the voltage divider output end with a reference voltage, generate a corresponding pulse width control signal according to the comparison result, and output the pulse width control signal to the voltage conversion module.

6. The power supply control circuit according to claim 5, characterized in that: The feedback module includes: an error amplification unit, a zero-pole compensation unit, a comparison unit and a sampling unit; The first input terminal of the error amplifying unit is electrically connected to the feedback input terminal, the second input terminal of the error amplifying unit is connected to the reference voltage, and the output terminal of the error amplifying unit is electrically connected to the first input terminal of the comparison unit; The pole-zero compensation unit is electrically connected to the first input terminal of the error amplification unit and the output terminal of the error amplification unit, and the pole-zero compensation unit is used to compensate for the zeros and poles of the feedback module; The sampling unit is used to sample the current of the voltage input terminal and generate a sawtooth wave, and the second input terminal of the comparison unit is connected to the sawtooth wave; the output terminal of the comparison unit is electrically connected to the voltage conversion module; Preferably, the pole-zero compensation unit comprises a type III compensator; Preferably, the feedback module further includes a latch unit, and the output end of the comparison unit is electrically connected to the voltage conversion module through the latch unit.

7. The power supply control circuit according to claim 1, characterized in that: The voltage conversion module includes a first transistor, a diode, an inductor, and a first capacitor, wherein a first end of the first transistor is electrically connected to the voltage input end, a second end of the first transistor is electrically connected to a first end of the inductor, and a second end of the inductor is electrically connected to the first power output end; The cathode of the diode is electrically connected to the second end of the first transistor, and the anode of the diode is electrically connected to the reference ground terminal of the voltage conversion module; The first end of the first capacitor is electrically connected to the second end of the inductor, and the second end of the first capacitor is electrically connected to the reference ground end.

8. The power supply control circuit according to claim 1, wherein: The power supply control circuit further includes a processing module, and the processing module is used to configure parameters of the power supply control circuit; Preferably, the parameters of the power supply control circuit include parameters of at least one of the voltage divider module and the feedback module; Preferably, the power supply control circuit further includes a storage module, in which a correspondence between the parameters of the power supply control circuit and the load current of the power supply control circuit is stored; the processing module is used to call the parameters of the voltage divider module in the storage module to configure the power supply control circuit according to the load current of the power supply control module; Preferably, the corresponding relationship between the parameters of the power supply control circuit and the load current of the power supply control circuit is obtained by the following method: Determining a maximum current, a minimum current, a first power supply voltage, and a second power supply voltage corresponding to a load of the power supply control circuit; The current to be calculated is obtained by traversing at preset intervals within the range of the minimum value of the current and the maximum value of the current, and the parameters of the power supply control circuit corresponding to the current to be calculated are calculated according to the current to be calculated, the first power supply voltage and the second power supply voltage.

9. A power management chip, characterized in that: The power management chip includes the power supply control circuit according to any one of claims 1 to 8.

10. A display module, characterized in that: The display module comprises the power management chip and the display panel according to claim 9; The display panel includes a plurality of light emitting elements, the first power output end is electrically connected to the first ends of the light emitting elements, and the second power output end is electrically connected to the second ends of the light emitting elements.

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