Power management system and display panel

Abstract

The invention provides a power management system and a display panel, and belongs to the technical field of display. The power management system comprises a test voltage generation sub-circuit which is configured to generate a corresponding test voltage based on an external environment temperature; the first comparison sub-circuit is configured to judge whether the external environment temperature is in a normal temperature section or a high temperature section based on a comparison result of the test voltage and a first reference voltage so as to generate a corresponding first control voltage; and the working level output sub-circuit is configured to output a corresponding working level signal based on the first control voltage.

Description

Power management system and display panel Technical Field

[0001] The present disclosure belongs to the field of display technology, and particularly relates to a power management system and a display panel. Background Art

[0002] With the continuous development of display technology and the increasing refresh rates of display products, heating issues are becoming increasingly serious in the wiring areas of display panels' corners. Wiring in the corners of display panels typically contains drive signal lines or circuits. Due to the high refresh rate, heating issues are easily caused by current effects, which in turn affect signal transmission, resulting in poor display quality and even a serious reduction in the reliability of the display panel.

[0003] Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art and provides a power management system and a display panel.

[0005] In a first aspect, an embodiment of the present disclosure provides a power management system, comprising:

[0006] A test voltage generating subcircuit is configured to generate a corresponding test voltage based on an external ambient temperature;

[0007] a first comparison subcircuit configured to determine whether the ambient temperature is in a normal temperature range or a high temperature range based on a comparison result between the test voltage and a first reference voltage, so as to generate a corresponding first control voltage;

[0008] The working level output sub-circuit is configured to output a corresponding working level signal based on the first control voltage.

[0009] Wherein, the power management system further includes:

[0010] a second comparison subcircuit configured to determine whether the ambient temperature is in a low temperature range based on a comparison result between the test voltage and a second reference voltage, so as to generate a corresponding second control voltage;

[0011] The working level output sub-circuit is further configured to output a corresponding working level signal according to the first control voltage and the second control voltage.

[0012] Wherein, the second comparison sub-circuit includes: a second comparator, a second transistor and a second resistor;

[0013] The non-inverting input terminal of the second comparator is connected to the second reference voltage terminal, the inverting input terminal is connected to the test voltage generation sub-circuit, and the output terminal is connected to the control electrode of the second transistor; the first electrode of the second transistor is connected to the first power supply voltage terminal through the second resistor, and the second electrode is connected to the second power supply voltage terminal.

[0014] Wherein, the second comparison circuit further includes a fifth resistor and a sixth resistor;

[0015] The fifth resistor is connected between the second reference voltage terminal and the non-inverting input terminal of the second comparator; and the sixth resistor is connected between the non-inverting input terminal and the output terminal of the second comparator.

[0016] The power management system further includes a second reference voltage generating sub-circuit configured to generate the second reference voltage based on the third power supply voltage.

[0017] Wherein, the second reference voltage generating sub-circuit includes a ninth resistor and a tenth resistor;

[0018] The first end of the ninth resistor is connected to the third power supply voltage terminal, the second end is connected to the first end of the tenth resistor, the second end of the tenth resistor is connected to the fourth power supply voltage terminal, and the second end of the ninth resistor and the first end of the tenth resistor are both electrically connected to the non-inverting input terminal of the second comparator.

[0019] Among them, the working level output sub-circuit includes a timing control module and a power management module; the timing control module is configured to determine whether the external ambient temperature is in the low temperature section, the normal temperature section or the high temperature section based on the first control voltage and the second control voltage, so as to control the power management module to output the corresponding working level signal.

[0020] Among them, the timing control module is specifically configured to determine whether the external ambient temperature is in the low temperature section, the normal temperature section or the high temperature section based on the first control voltage and the second control voltage, control the power management module to a preset adjustment period, and periodically adjust the output working level signal according to the preset adjustment value until the corresponding working level signal is output.

[0021] Wherein, the timing control module and the power management module are connected via I2C communication.

[0022] Wherein, the working level output sub-circuit includes a low temperature compensation module and a power management module;

[0023] The low temperature compensation module is configured to control the power management module to output a corresponding working level signal in response to the external environment temperature being in the low temperature range.

[0024] Among them, the working level output sub-circuit also includes a timing control module; the timing control module is configured to determine whether the external ambient temperature is in the normal temperature range or the high temperature range based on the first control voltage, so as to control the output of the corresponding working level signal of the power management module.

[0025] Among them, the timing control module is specifically configured to determine whether the external ambient temperature is in the normal temperature range or the high temperature range based on the first control voltage, control the power management module to a preset adjustment period, and periodically adjust the output working level signal according to the preset adjustment value until the corresponding working level signal is output.

[0026] Wherein, the timing control module and the power management module are connected via I2C communication.

[0027] Wherein, the first comparison sub-circuit includes a first comparator, a first transistor and a first resistor;

[0028] The non-inverting input terminal of the first comparator is connected to the first reference voltage terminal, the inverting input terminal is connected to the test voltage generation sub-circuit, and the output terminal is connected to the control electrode of the first transistor; the first electrode of the first transistor is connected to the first power supply voltage terminal through the first resistor, and the second electrode is connected to the second power supply voltage terminal.

[0029] Wherein, the first comparison circuit further includes a third resistor and a fourth resistor;

[0030] The third resistor is connected between the first reference voltage terminal and the non-inverting input terminal of the first comparator; and the fourth resistor is connected between the non-inverting input terminal and the output terminal of the first comparator.

[0031] The power management system further includes a first reference voltage generating sub-circuit configured to generate the first reference voltage based on a third power supply voltage.

[0032] Wherein, the first reference voltage generating subcircuit includes a seventh resistor and an eighth resistor;

[0033] The first end of the seventh resistor is connected to the third power supply voltage terminal, the second end is connected to the first end of the eighth resistor, the second end of the eighth resistor is connected to the fourth power supply voltage terminal, and the second end of the seventh resistor and the first end of the eighth resistor are both electrically connected to the non-inverting input terminal of the first comparator.

[0034] Wherein, the test voltage generating subcircuit includes a thermistor and a voltage dividing resistor;

[0035] The first end of the voltage divider resistor is connected to the third power supply voltage end, the second end is connected to the first end of the thermistor, the second end of the thermistor is connected to the fourth power supply voltage end, and the second end of the voltage divider resistor and the first end of the thermistor are connected at the same time, and are configured to output the test voltage.

[0036] In a second aspect, an embodiment of the present disclosure provides a display panel comprising any of the power management systems described above.

[0037] Among them, the display panel also includes a gate drive circuit, the working level signal output by the power management system is a high level signal, and the working level output subcircuit of the power management system is connected to the high level signal end of each shift register in the gate drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG1 is a schematic diagram of a first exemplary power management system according to an embodiment of the present disclosure.

[0039] FIG2 is a diagram showing the relationship between test voltage and temperature in a first example of an embodiment of the present disclosure.

[0040] FIG3 is a schematic diagram of a first comparison sub-circuit and a second comparison sub-circuit of a first example of an embodiment of the present disclosure.

[0041] FIG. 4 is a diagram showing the relationship between the voltage of the high-level signal VGH and the temperature according to a first example of an embodiment of the present disclosure.

[0042] FIG5 is a partial schematic diagram of a first exemplary power management system according to an embodiment of the present disclosure.

[0043] FIG6 is an output waveform diagram of the first output sub-circuit of the first example of the embodiment of the present disclosure.

[0044] FIG. 7 is a diagram showing the relationship between the voltage of the high-level signal VGH and the temperature after optimization according to the first example of the embodiment of the present disclosure.

[0045] FIG8 is a partial schematic diagram of a first exemplary power management system according to an embodiment of the present disclosure.

[0046] FIG9 is a schematic diagram of a second exemplary power management system according to an embodiment of the present disclosure.

[0047] FIG10 is a diagram showing the relationship between the voltage of the high-level signal VGH and the temperature after optimization according to the second example of the embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0049] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0050] Before describing the embodiments of the present disclosure, it should be noted that the operating level signal output by the power management system of the present disclosure embodiment can be a positive voltage signal or a negative voltage signal, wherein the positive voltage signal is referred to as a high-level signal and the negative voltage signal is referred to as a low-level signal. In the embodiments of the present disclosure, only the operating level signal is described as a high-level signal. At the same time, the high-level signal output by the power management system of the present disclosure embodiment is mainly used in the various shift registers of the gate drive circuit of the display panel as an example. However, it should be understood that this does not constitute a limitation on the scope of protection of the embodiments of the present disclosure. In the disclosed embodiment, the thermistor in the test voltage generation subcircuit is a thermistor with a negative temperature coefficient. At this time, the test voltage generated when the external ambient temperature is in the low temperature section is the highest, the test voltage generated in the normal temperature section is the second lowest, and the test voltage generated in the high temperature section is the lowest. In the embodiments of the present disclosure, the first power supply voltage is larger than the second power supply voltage, and the third power supply voltage is larger than the fourth power supply voltage.

[0051] In the existing technology, for conventional products, a constant high-level signal VGH can meet the requirements. However, for high-end products with high resolution and high refresh rate, there is a risk of insufficient high-level signal margin in low-temperature environments and excessively high PLG temperature in high-temperature environments. At this time, temperature compensation is required to ensure that the display panel is in the best condition under various ambient temperature changes.

[0052] The inventors have discovered that existing products only have a low-temperature compensation function. The power management chip can only perform low-temperature compensation on the output high-level signal VGH according to temperature changes. That is, as shown in Figure XX, it can only achieve a high-level voltage of two steps, with a linear change in the middle part.

[0053] For high-resolution, high-refresh-rate α-Si products, charging rates are inherently challenging. Low-temperature environments present the risk of insufficient VGH margin for high-level signals, while high-temperature PLG temperatures can overheat and even burn out the Pol. Considering the TFT characteristic curve, carrier mobility decreases in the low-temperature range, shifting the TFT characteristic curve to the right; while carrier mobility increases in the high-temperature range, shifting the TFT characteristic curve to the left.

[0054] In a high-temperature environment, at the same high-level VGH voltage, Ids decreases, and the pixel voltage of the liquid crystal decreases. As time goes by, the accumulated voltage loss increases, causing the display to fail to start normally. From the perspective of the liquid crystal, in a low-temperature environment, the rotation speed of the liquid crystal molecules decreases, and normal liquid crystal deflection cannot be achieved. The above factors lead to a low-temperature reliability black screen, which can be solved by increasing the high-level VGH voltage.

[0055] In a high-temperature environment, excessively high temperatures put the liquid crystal at risk of exceeding the clearing point. Changes in the liquid crystal state directly lead to abnormal display images and are usually irreversible, resulting in poor display and even Pol burning. This usually occurs at corners where the PLG temperature is higher. The wiring there is complex, and within the limited space, only narrow wiring can be designed, resulting in increased resistance and heat accumulation. This problem also exists in the application of extremely narrow-framed products. This problem can be solved by reducing the high-level VGH voltage. According to the TFT characteristic curve, a smaller voltage can achieve the same display effect at high temperatures, and the service life of the device can also be increased. In addition to this problem in products with high resolution and high refresh rate, the PLG temperature of extremely narrow-framed products also faces severe tests.

[0056] Existing high-end power management chips (PMICs) have a compensation function for the increased high-level VGH at low temperatures, but the industry currently lacks a function for reducing the high-level VGH voltage in high-temperature environments. Therefore, the embodiments of the present disclosure provide the following technical solutions.

[0057] In a first aspect, embodiments of the present disclosure provide a power management system capable of adjusting an output high-level signal based on a determination of whether the ambient temperature is in a low-temperature range, a normal-temperature range, or a high-temperature range, to output a high-level signal adapted to the ambient temperature. In embodiments of the present disclosure, the power management chip is configured to initially output a high-level signal corresponding to a low-temperature range or a normal-temperature range by default. The power management system in embodiments of the present disclosure is described below with reference to specific examples.

[0058] The first example: In this example, the power management system initially defaults to outputting a high-level signal corresponding to the low-temperature section. Figure 1 is a schematic diagram of the power management system of the first example of an embodiment of the present disclosure; as shown in Figure 1, the power management system includes a test voltage generation subcircuit 11, a first comparison subcircuit 12, a second comparison subcircuit 14, and a working level output subcircuit 13. Among them, the test voltage generation subcircuit 11 is configured to generate a corresponding test voltage based on the third power supply voltage VDD2 and according to the external ambient temperature. The first comparison subcircuit 12 is configured to determine whether the external ambient temperature is in the normal temperature section or the high temperature section based on the comparison result of the test voltage and the first reference voltage Vref1, so as to generate a corresponding first control voltage. The second comparison subcircuit 14 is configured to determine whether the external ambient temperature is in the low-temperature section based on the comparison result of the test voltage and the second reference voltage Vref2, so as to generate a second control voltage. The working level output subcircuit 13 includes a timing control module 131 and a power management module 132; the timing control module 131 is configured to determine whether the external ambient temperature is in the low temperature range, the normal temperature range or the high temperature range based on the first control voltage and the second control voltage, so as to control the power management module 132 to output the corresponding working level signal.

[0059] For example, FIG2 is a diagram showing the relationship between the test voltage and temperature of the first example of the embodiment of the present disclosure; as shown in FIG2, the low temperature section is when the ambient temperature is less than or equal to 0°C, the normal temperature section is when the ambient temperature is between 0°C and 50°C, and the high temperature section is when the ambient temperature is greater than or equal to 50°C. Among them, the first reference voltage Vref1 is the test voltage V generated by the test voltage generating subcircuit 11 when the ambient temperature is 0°C. FB_0 The second reference voltage Vref2 is the test voltage V generated by the test voltage generation sub-circuit 11 when the ambient temperature is 50°C. FB_50 .

[0060] In the first case, when the ambient temperature is less than or equal to 0°C, the test voltage generated by the test voltage generating sub-circuit 11 is greater than V FB_0 , that is, greater than the second reference voltage Vref2, the second comparison sub-circuit 14 then determines that the ambient temperature is in the low temperature range based on the comparison result, and for example, the output second control voltage is the first power supply voltage VDD1. At the same time, the second control voltage output by the second comparison sub-circuit 14 is the second power supply voltage VSS1. The timing control module 131 controls the power management module 132 to output a high-level signal corresponding to the low temperature range based on the outputs of the first comparison sub-circuit 12 and the second comparison sub-circuit 14.

[0061] In the second case, when the ambient temperature is greater than 0°C and less than 50°C, the test voltage generated by the test voltage generating sub-circuit 11 is less than VFB_0 , that is, less than the second reference voltage Vref2, the second comparison sub-circuit 14 then determines that the ambient temperature is in a non-low temperature range, that is, in a normal temperature range or a high temperature range, and for example, the output second control voltage is the second power supply voltage VSS1. The test voltage generated by the test voltage generation sub-circuit 11 is greater than V FB_50 , that is, greater than the first reference voltage Vref1, at this time, the first comparison sub-circuit 12 determines that it is not in the high temperature section, that is, it is in the low temperature section or the normal temperature section. For example, the output first control voltage is the second power supply voltage VSS1, and according to the first comparison sub-circuit 12 and the second comparison sub-circuit 14, it can be determined that the external ambient temperature is in the normal temperature section. The timing control module 131 controls the power management module 132 to output a high-level signal corresponding to the low temperature section according to the outputs of the first comparison sub-circuit 12 and the second comparison sub-circuit 14.

[0062] In the third case, when the ambient temperature is greater than 50°C, the test voltage generated by the test voltage generating sub-circuit 11 is less than V FB_50 , that is, less than the first reference voltage Vref1, and of course also less than the second reference voltage Vref2. At this time, the second comparison sub-circuit 14 determines that the external ambient temperature is in a non-low temperature range, that is, in a normal temperature range or a high temperature range. For example, the output second control voltage is the second power supply voltage VSS1. The test voltage generated by the test voltage generation sub-circuit 11 is less than V FB_50 , that is, less than the first reference voltage Vref1, at this time, the first comparison sub-circuit 12 determines that it is in the high temperature section, for example, the output first control voltage is the first power supply voltage VDD1, and according to the first comparison sub-circuit 12 and the second comparison sub-circuit 14, it can be determined that the external ambient temperature is in the normal temperature section. The timing control module 131 controls the power management module 132 to output a high-level signal corresponding to the low temperature section according to the outputs of the first comparison sub-circuit 12 and the second comparison sub-circuit 14.

[0063] In some examples, FIG3 is a schematic diagram of a first comparison subcircuit 12 and a second comparison subcircuit 14 of a first example of an embodiment of the present disclosure. As shown in FIG3 , the first comparison subcircuit 12 includes a first comparator OP1, a first resistor R1, and a first transistor. The first comparator OP1 has a non-inverting input connected to a first reference voltage terminal Ref1, an inverting input connected to a test voltage generation subcircuit 11, and an output connected to a control electrode of the first transistor. The first electrode of the first transistor is connected to a first power supply voltage VDD1 via a first resistor R1, and a second electrode is connected to a second power supply voltage VSS1.

[0064] 2 and 3 , when the test voltage generated by the test voltage generation subcircuit 11 is greater than the first reference voltage Vref1, the ambient temperature is either in the low temperature range or the normal temperature range, the output terminal of the first comparator OP1 outputs a low level L, the first transistor is turned off, and the first control voltage outputted by the first signal output terminal output1 is the first power supply voltage VDD1. When the test voltage generated by the test voltage generation subcircuit 11 is less than the first reference voltage Vref1, the ambient temperature is either in the high temperature range, the output terminal of the first comparator OP1 outputs a high level H, the first transistor is turned on, and the first control voltage outputted by the first signal output terminal output1 is the second power supply voltage VSS1.

[0065] In some examples, with continued reference to FIG3 , the second comparison sub-circuit 14 includes a second comparator OP2, a second resistor R2, and a second transistor. The second comparator OP2 has a non-inverting input connected to the second reference voltage terminal Ref2, an inverting input connected to the test voltage generation sub-circuit 11, and an output connected to the control electrode of the second transistor. The first electrode of the second transistor is connected to the first power supply voltage VDD1 via the second resistor R2, and the second electrode is connected to the second power supply voltage VSS1.

[0066] 2 and 3 , when the test voltage generated by the test voltage generation subcircuit 11 is greater than the second reference voltage Vref2, the ambient temperature is in the low temperature range, the output terminal of the second comparator OP2 outputs a low level L, the second transistor is turned off, and the second control voltage output by the second signal output terminal output2 is the first power supply voltage VDD1. When the test voltage generated by the test voltage generation subcircuit 11 is less than the second reference voltage Vref2, the ambient temperature is in the normal temperature range or the high temperature range, the output terminal of the second comparator OP2 outputs a high level H, the second transistor is turned on, and the second control voltage output by the second signal output terminal output2 is the second power supply voltage VSS1.

[0067] Furthermore, FIG4 is a diagram showing the relationship between the voltage of the high-level signal VGH and temperature according to a first example of an embodiment of the present disclosure. As shown in FIG4 , when the first comparison sub-circuit 12 includes the aforementioned first comparator OP1, the first transistor, and the first resistor R1, and the second comparison sub-circuit 14 includes the second comparator OP2, the second transistor, and the second resistor R2, the first signal output terminal output1 of the first sub-circuit and the second signal output terminal output2 of the second comparison sub-circuit 14 are respectively connected to the timing control module 131 via two IO (input / output) interfaces. In this way, when the first control voltage received by the timing control module 131 is the second power supply voltage VSS1 and the second control voltage is the first power supply voltage VDD1, the power management module 132 is controlled to output a high-level signal corresponding to the low-temperature range (i.e., 41V in the figure). When the first control voltage received by the timing control module 131 is the second power supply voltage VSS1 and the second control voltage is the second power supply voltage VDD1, the power management module 132 is controlled to output a high-level signal corresponding to the normal temperature range (i.e., 32V in the figure). When the first control voltage received by the timing control module 131 is the first power voltage VDD1 and the second control voltage is the second power voltage VSS1 , the power management module 132 is controlled to output a high level signal corresponding to the high temperature range (ie, 27V in the figure).

[0068] In some examples, FIG5 is a partial schematic diagram of a power management system of a first example of an embodiment of the present disclosure; as shown in FIG5, the first comparison subcircuit 12 includes not only the first comparator OP1, the first transistor and the first resistor R1 described above, but also includes a third resistor R3 and a fourth resistor R4, the third resistor R3 being connected between the first reference voltage terminal Ref1 and the non-inverting input terminal of the first comparator OP1; and the fourth resistor R4 being connected between the non-inverting input terminal and the output terminal of the first comparator OP1. The addition of the third resistor R3 and the fourth resistor R4 can achieve inverting input hysteresis, thereby effectively avoiding the problem that when the external link temperature fluctuates near the critical point temperature (for example, when the external ambient temperature fluctuates at 49°C, 50°C, or 51°C), the test voltage input to the non-inverting input terminal of the first comparator OP1 is unstable and jitters, the output terminal of the first comparator OP1 is unstable, thereby causing the high-level signal output by the power management module 132 to jitter.

[0069] Specifically, the first reference voltage Vref1 is a fixed preset value. As the ambient temperature changes, the test voltage generated by the test voltage generating sub-circuit 11 changes accordingly. When the first reference voltage Vref1 is equal to the test voltage, it is not the inflection point of the output of the first comparator OP1 (this point is taken as the inflection point in FIG4 ). In the process of the ambient temperature changing from high to low, V i When increasing from small to large, the turning point of the change is (V ref1 Large); when the external environment temperature changes from low to high, V i When decreasing from large to small, the inflection point is U L (V ref1 Small), thus obtaining an upper threshold U H and the lower threshold U L .U H =U - =U + =V ref1 +I*R3=R4*V ref1 / (R3+R4)+R3*V o1+ / (R3+R4); U L =U - =U + =V ref1 -I*R3=R4*V ref1 / (R3+R4)+R3*V o1- / (R3+R4).

[0070] When the external temperature changes, the V i When within the threshold, the output state of the first comparator OP1 remains unchanged. Once the threshold is broken and the state changes, the inflection point for returning to the previous state changes. FIG6 is an output waveform diagram of the first output sub-circuit of the first example of the embodiment of the present disclosure; As shown in FIG6, when V i Increase to V i >U H , the output of the first comparator OP1 changes from high level to low level, at this time when V i Lower, to V i <U H , the output of the first comparator OP1 will not change from low level to high level, and V i Reduce to V i <U L , the output of the first comparator OP1 changes from a low level to a high level, thereby ensuring the stability of the output of the first comparator OP1.

[0071] Based on the same principle as the first comparison sub-circuit 12, the second comparison sub-circuit 14 not only includes the above-mentioned second comparator OP2, the second transistor and the second resistor R2, but also includes a fifth resistor and a sixth resistor. The fifth resistor is connected between the second reference voltage terminal Ref2 and the non-inverting input terminal of the second comparator OP2; the sixth resistor is connected between the non-inverting input terminal and the output terminal of the second comparator OP2. The added fifth resistor and sixth resistor can achieve inverting input hysteresis, thereby effectively avoiding the problem that when the external link temperature fluctuates near the critical point temperature (for example, when the external ambient temperature fluctuates at -1°C, 0°C, and 1°C), the test voltage input to the non-inverting input terminal of the second comparator OP2 is unstable and jitters, the output terminal of the second comparator OP2 is unstable, thereby causing the high-level signal output by the power management module 132 to jitter. The specific working principle is similar to the above principle, so it will not be repeated here.

[0072] In some examples, referring to FIG4 , when the power management module 132, under the control of the timing control module 131, adjusts the output high-level signal according to the temperature range of the external ambient temperature, it can be seen that the high-level signal jumps directly from a certain voltage value to another voltage value. In this way, the display of the display panel will flicker, and it can be recognized by the human eye. In the embodiment of the present disclosure, FIG7 is a diagram showing the relationship between the voltage and temperature of the high-level signal VGH after optimization of the first example of the embodiment of the present disclosure; as shown in FIG7 , to avoid the occurrence of this problem, the timing control module 131 in the embodiment of the present disclosure can determine whether the external ambient temperature is in the low temperature range, the normal temperature range, or the high temperature range based on the first control voltage and the second control voltage, and control the power management module 132 to preset an adjustment period and periodically adjust the output high-level signal according to the preset adjustment value until the corresponding high-level signal is output. In other words, when adjusting the current high-level signal, the power management module 132, under the control of the timing control module 131, will gradually increase or decrease the voltage value according to a preset time interval, i.e., the adjustment period, until the output is a high-level signal that satisfies the temperature range of the current ambient temperature. The preset voltage adjustment value for each adjustment is the minimum change value of the high-level voltage of the power management module 132.

[0073] In some examples, the timing control module 131 and the power management module 132 are connected via I2C communication. The I2C is composed of a data line SDA and a clock line SCL, and can send and receive data. It performs bidirectional transmission between the timing control module 131 and the power management module 132, and adjusts the CODE of the power management module 132 via the I2C signal output by the timing control module 131.

[0074] In some examples, the power management system of the present disclosure includes not only the aforementioned structure but also a first reference voltage Vref1 generation module that generates a first reference voltage Vref1 based on a third power supply voltage VDD2. Similarly, a second reference voltage Vref2 generation module that generates a second reference voltage Vref2 based on the third power supply voltage VDD2 may also be included. Both the first reference voltage Vref1 generation module and the second power supply voltage VSS1 generation module may be formed by a voltage divider circuit, wherein the corresponding reference voltage value may be obtained by properly setting the resistance value of the resistor in the voltage divider circuit.

[0075] For example, FIG8 is a partial schematic diagram of a power management system according to a first example of an embodiment of the present disclosure. As shown in FIG8 , a circuit for generating a first reference voltage Vref1 may include a seventh resistor R7 and an eighth resistor R8. The first end of the seventh resistor R7 is connected to the third power supply voltage VDD2, the second end is connected to the first end of the eighth resistor R8, the second end of the eighth resistor R8 is connected to the fourth power supply voltage VSS2, and the second end of the seventh resistor R7 and the first end of the eighth resistor R8 are both electrically connected to the non-inverting input of the first comparator OP1. By properly setting the resistance values ​​of the seventh resistor R7 and the eighth resistor R8, the corresponding first reference voltage Vref1 can be obtained.

[0076] For example, the second reference voltage Vref2 generation subcircuit includes a ninth resistor and a tenth resistor. A first end of the ninth resistor is connected to the third power supply voltage VDD2, a second end is connected to the first end of the tenth resistor, a second end of the tenth resistor is connected to the fourth power supply voltage VSS2, and both the second end of the ninth resistor and the first end of the tenth resistor are electrically connected to the non-inverting input of the second comparator OP2. By properly setting the resistance values ​​of the seventh resistor R7 and the eighth resistor R8, a corresponding second reference voltage Vref2 can be obtained.

[0077] In some embodiments, the test voltage generating subcircuit 11 may be composed of a voltage divider circuit. For example, the test voltage generating subcircuit 11 includes a thermistor and a voltage divider resistor. The first end of the voltage divider resistor is connected to the third power supply voltage VDD2 terminal, the second end is connected to the first end of the thermistor, the second end of the thermistor is connected to the fourth power supply voltage VSS2 terminal, and the second end of the voltage divider resistor and the first end of the thermistor are connected at the same time, and are configured to output the test voltage. It should be noted that the number of voltage divider resistors can be one or more. The thermistor can have a positive temperature coefficient or a negative temperature coefficient. In the embodiment disclosed herein, only the thermistor with a negative temperature coefficient is used as an example.

[0078] Second Example: Figure 9 is a schematic diagram of a power management system according to a second example of an embodiment of the present disclosure. As shown in Figure 9, the power management system in this example initially defaults to outputting a high-level signal corresponding to the normal temperature range. This power management system includes a test voltage generation subcircuit 11, a first comparison subcircuit 12, and an operating level output subcircuit 13. The level output subcircuit includes a low-temperature compensation module 133, a timing module, and a power management module 132. The test voltage generation subcircuit 11 is configured to generate a corresponding test voltage based on a third power supply voltage VDD2 and the ambient temperature. The first comparison subcircuit 12 is configured to determine whether the ambient temperature is within the normal temperature range or the high temperature range based on a comparison result between the test voltage and a first reference voltage Vref1, and to generate a corresponding first control voltage. The timing control module 131 controls the power management module 132 to output a corresponding operating level signal based solely on the first control voltage. The low-temperature compensation module 133 is configured to control the power management module 132 to output a corresponding operating level signal in response to the ambient temperature being within the low temperature range. That is, for the power management system, the power management module 132 can directly perform low temperature compensation based on the low temperature compensation module 133 therein. At this time, the timing control module 131 only needs to adjust the high level signal for the high temperature section and the low temperature section.

[0079] In this example, the test voltage generating subcircuit 11 and the first comparing subcircuit 12 may both adopt the same circuit structure as in the first example, so the working principle will not be described again here.

[0080] In this example, Figure 10 shows the relationship between the voltage of the high-level signal VGH and temperature after optimization according to the second example of the present embodiment. As shown in Figure 10, when the ambient temperature is in the low-temperature range, the low-temperature compensation module 133 adjusts the voltage of the power management module 132 in a linear and monotonic manner. The timing control module 131 is specifically configured to determine whether the ambient temperature is in the normal temperature range or the high temperature range based on the first control voltage, and control the power management module 132 to periodically adjust the output working level signal according to the preset adjustment value at a preset adjustment period until the corresponding working level signal is output. In other words, when adjusting the current high-level signal, the power management module 132, under the control of the timing control module 131, will stepwise increase or decrease the voltage value at preset time intervals, i.e., the adjustment period, until the output high-level signal meets the temperature range of the current ambient temperature. The preset voltage adjustment value for each adjustment is the minimum change value of the high-level voltage of the power management module 132. This approach effectively prevents display flicker.

[0081] In a second aspect, an embodiment of the present disclosure provides a display panel comprising the above-mentioned power management system.

[0082] In some examples, the display panel also includes a gate drive circuit, the operating level signal output by the power management system is a high level signal, and the operating level output sub-circuit of the power management system is connected to the high level signal end of each shift register in the gate drive circuit.

[0083] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A power management system, comprising: A test voltage generating subcircuit is configured to generate a corresponding test voltage based on an external ambient temperature; A first comparison subcircuit is configured to determine whether the ambient temperature is in a normal temperature range or a high temperature range based on a comparison result between the test voltage and the first reference voltage, so as to generate a corresponding first control voltage; The working level output subcircuit is configured to output a corresponding working level signal based on the first control voltage.

2. The power management system according to claim 1, wherein: Also includes: A second comparison subcircuit is configured to determine whether the ambient temperature is in a low temperature section based on a comparison result between the test voltage and the second reference voltage, so as to generate a corresponding second control voltage; The working level output subcircuit is further configured to output a corresponding working level signal according to the first control voltage and the second control voltage.

3. The power management system according to claim 2, wherein: The second comparison subcircuit comprises: a second comparator, a second transistor and a second resistor; The non-inverting input terminal of the second comparator is connected to the second reference voltage terminal, the inverting input terminal is connected to the test voltage generating sub-circuit, and the output terminal is connected to the control electrode of the second transistor; the first electrode of the second transistor is connected to the first power supply voltage terminal through the second resistor, and the second electrode is connected to the second power supply voltage terminal.

4. The power management system according to claim 3, wherein: The second comparison circuit also includes a fifth resistor and a sixth resistor; The fifth resistor is connected between the second reference voltage terminal and the non-inverting input terminal of the second comparator; and the sixth resistor is connected between the non-inverting input terminal and the output terminal of the second comparator.

5. The power management system according to claim 2, wherein: The circuit further includes a second reference voltage generating subcircuit configured to generate the second reference voltage based on a third power supply voltage.

6. The power management system according to claim 5, wherein: The second reference voltage generating subcircuit includes a ninth resistor and a tenth resistor; The first end of the ninth resistor is connected to the third power supply voltage terminal, the second end is connected to the first end of the tenth resistor, the second end of the tenth resistor is connected to the fourth power supply voltage terminal, and the second end of the ninth resistor and the first end of the tenth resistor are both electrically connected to the non-inverting input terminal of the second comparator.

7. The power management system according to claim 2, wherein: The working level output subcircuit includes a timing control module and a power management module; The timing control module is configured to determine whether the external ambient temperature is in the low temperature section, the normal temperature section or the high temperature section based on the first control voltage and the second control voltage, so as to control the power management module to output a corresponding working level signal.

8. The power management system according to claim 7, wherein: The timing control module is specifically configured to determine whether the external ambient temperature is in the low temperature section, the normal temperature section or the high temperature section based on the first control voltage and the second control voltage, control the power management module to a preset adjustment period, and periodically adjust the output working level signal according to the preset adjustment value until the corresponding working level signal is output.

9. The power management system according to claim 7, wherein: The timing control module and the power management module are connected via I2C communication.

10. The power management system according to claim 1, wherein: The working level output subcircuit includes a low temperature compensation module and a power management module; The low temperature compensation module is configured to control the power management module to output a corresponding working level signal in response to the external environment temperature being in the low temperature section.

11. The power management system according to claim 10, wherein: The working level output subcircuit also includes a timing control module; the timing control module is configured to determine whether the external ambient temperature is in the normal temperature range or the high temperature range based on the first control voltage, so as to control the power management module to output a corresponding working level signal.

12. The power management system according to claim 11, wherein: The timing control module is specifically configured to determine whether the external ambient temperature is in the normal temperature range or the high temperature range based on the first control voltage, control the power management module to a preset adjustment period, and periodically adjust the output working level signal according to the preset adjustment value until the corresponding working level signal is output.

13. The power management system according to claim 11, wherein: The timing control module and the power management module are connected via I2C communication.

14. The power management system according to any one of claims 1 to 13, wherein: The first comparison subcircuit includes a first comparator, a first transistor and a first resistor; The non-inverting input terminal of the first comparator is connected to the first reference voltage terminal, the inverting input terminal is connected to the test voltage generating sub-circuit, and the output terminal is connected to the control electrode of the first transistor; The first electrode of the first transistor is connected to the first power supply voltage terminal through the first resistor, and the second electrode is connected to the second power supply voltage terminal.

15. The power management system according to claim 14, wherein: The first comparison circuit also includes a third resistor and a fourth resistor; The third resistor is connected between the first reference voltage terminal and the non-inverting input terminal of the first comparator; and the fourth resistor is connected between the non-inverting input terminal and the output terminal of the first comparator.

16. The power management system according to claim 14, wherein: The circuit further includes a first reference voltage generating subcircuit configured to generate the first reference voltage based on a third power supply voltage.

17. The power management system according to claim 16, wherein: The first reference voltage generating subcircuit includes a seventh resistor and an eighth resistor; The first end of the seventh resistor is connected to the third power supply voltage terminal, the second end is connected to the first end of the eighth resistor, the second end of the eighth resistor is connected to the fourth power supply voltage terminal, and the second end of the seventh resistor and the first end of the eighth resistor are both electrically connected to the non-inverting input terminal of the first comparator.

18. The power management system according to any one of claims 1 to 13, wherein: The test voltage generating subcircuit includes a thermistor and a voltage dividing resistor; The first end of the voltage-dividing resistor is connected to the third power supply voltage end, the second end is connected to the first end of the thermistor, the second end of the thermistor is connected to the fourth power supply voltage end, and the second end of the voltage-dividing resistor and the first end of the thermistor are connected at the same time, and are configured to output the test voltage.

19. A display panel comprising the power management system according to any one of claims 1-18.

20. The display panel according to claim 19, wherein: It also includes a gate drive circuit, the working level signal output by the power management system is a high level signal, and the working level output subcircuit of the power management system is connected to the high level signal end of each shift register in the gate drive circuit.

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