Low temperature start-up circuit, method, and display panel

Abstract

The present application discloses a low-temperature startup circuit, method, and display panel. The low-temperature startup circuit includes: a temperature sensing circuit, which is used to divide the voltage of a first power supply according to the temperature of an internal circuit of a display panel and output a temperature sensing signal; a switch circuit, wherein a first control end of the switch circuit is connected to an output end of the temperature sensing circuit and is used to open or close under the control of the temperature sensing signal; a heating control circuit, which forms a loop with the first power supply and the switch circuit and is used to output a first heating control signal at a first node of the loop; a heating circuit, which is connected to a first node of the heating control circuit and is used to heat the internal circuit of the display panel under the control of the first heating control signal if the temperature is less than a first preset temperature, so as to start the display panel. The embodiment of the present application controls the heating circuit according to the temperature of the internal circuit of the display panel to heat the internal circuit of the display panel when the display panel is in a low-temperature environment to start the display panel.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a low-temperature startup circuit, method, and display panel. Background Art

[0002] At room temperature, the conductivity of semiconductors is between conductors and insulators, and changes in temperature have a great impact on the conductivity, limiting voltage, limiting current, and switching characteristics of semiconductors. Therefore, electronic components usually have an operating temperature range. If the temperature range is exceeded, they will fail or their performance will degrade. Generally, the operating temperature range of civilian-grade devices is 0~70℃, that of industrial-grade devices is -40~85℃, and that of military-grade devices is -55~128℃.

[0003] A chip often contains millions or even tens of millions of transistors and other components. If the temperature of the chip's environment is too low, the chip will often be unable to turn on its internal semiconductor switch at the rated operating voltage, causing it to malfunction. Summary of the invention

[0004] Embodiments of the present application provide a low-temperature startup circuit, method, and display panel, which heat the internal circuit of the display panel when the display panel is in a low-temperature environment to start the display panel.

[0005] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0006] According to a first aspect of an embodiment of the present application, a low-temperature startup circuit is provided, which is applied to a display panel. The low-temperature startup circuit includes:

[0007] A temperature sensing circuit, used to divide the voltage of the first power supply according to the temperature of the internal circuit of the display panel and output a temperature sensing signal;

[0008] A switch circuit, wherein a first control terminal of the switch circuit is connected to an output terminal of the temperature sensing circuit and is configured to be opened or closed under the control of the temperature sensing signal;

[0009] a heating control circuit, forming a loop with the first power supply and the switch circuit, and configured to output a first heating control signal at a first node of the loop;

[0010] A heating circuit is connected to the first node of the heating control circuit, and is used to heat the internal circuit of the display panel under the control of the first heating control signal to start the display panel if the temperature is lower than a first preset temperature.

[0011] In some embodiments of the present application, based on the above solution, the heating control circuit further includes:

[0012] a logic operation circuit, wherein a first input terminal is connected to the start signal output terminal of the display panel, a second input terminal is connected to the first node of the loop, and an output terminal is connected to the heating circuit, and is used to perform a logic operation on the start signal of the display panel and the first heating control signal, and output a second heating control signal;

[0013] The heating circuit is connected to the output end of the logic operation circuit, and is used for heating the display panel under the control of the second heating control signal to start the display panel if the temperature is lower than the first preset temperature.

[0014] In some embodiments of the present application, based on the above solution, the temperature sensing circuit includes:

[0015] a thermistor, a first end of which is connected to the first power source and a second end of which is an output end of the temperature sensing circuit;

[0016] The first resistor has a first end connected to the second end of the thermistor and a second end grounded.

[0017] In some embodiments of the present application, based on the above solution, the thermistor is a negative temperature coefficient thermistor, and the switch circuit includes:

[0018] A first switch tube, having a gate connected to the output end of the temperature sensing circuit, a drain connected to the first node of the loop, and a source connected to the ground, is used to disconnect when the temperature is lower than the first preset temperature and to close when the temperature is higher than a second preset temperature, and the second preset temperature is higher than or equal to the first preset temperature.

[0019] In some embodiments of the present application, based on the above solution, the heating control circuit includes:

[0020] A second resistor has a first end connected to the first node of the loop and to the drain of the first switch tube, and a second end connected to the first power supply.

[0021] In some embodiments of the present application, based on the above solution, the thermistor is a positive temperature coefficient thermistor, and the switch circuit includes:

[0022] A second switch tube, having a gate connected to the output end of the temperature sensing circuit, a source connected to the first node of the loop, and a drain connected to the first power supply, is used to close when the temperature is lower than the first preset temperature and to open when the temperature is higher than a second preset temperature, and the second preset temperature is higher than or equal to the first preset temperature.

[0023] In some embodiments of the present application, based on the above solution, the heating control circuit includes:

[0024] A third resistor has a first end connected to the first node of the loop and to the drain of the second switch tube, and a second end connected to the ground.

[0025] In some embodiments of the present application, based on the above solution, the heating circuit includes:

[0026] a third switch tube, a control end of which is connected to the first node of the loop and is used to be opened or closed under the control of the first heating control signal;

[0027] The heating resistor forms a loop with the second power supply and the third switch tube, and is used to heat the display panel when the third switch tube is closed.

[0028] According to a second aspect of an embodiment of the present application, a method for starting a display panel at low temperature is provided, the method comprising:

[0029] The temperature sensing circuit divides the voltage of the first power supply according to the temperature of the internal circuit of the display panel to obtain a temperature sensing signal;

[0030] When the switch circuit receives the temperature sensing signal, it opens or closes, and the first control end of the switch circuit is connected to the output end of the temperature sensing circuit;

[0031] A first heating control signal is obtained by forming a loop through the heating control circuit, the first power supply and the switch circuit;

[0032] According to the first heating control signal, when the temperature is less than a first preset temperature, the internal circuit of the display panel is heated to start the display panel.

[0033] According to a third aspect of an embodiment of the present application, a display panel is provided, comprising a housing, a main circuit board, and the low-temperature starting circuit described in the first aspect.

[0034] In the embodiment of the present application, the heating circuit is controlled according to the temperature of the internal circuit of the display panel to heat the internal circuit of the display panel when the display panel is in a low temperature environment, so as to start the display panel.

[0035] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0037] Figure 1-A A schematic diagram of the structure of a low-temperature starting circuit provided in an embodiment of the present application.

[0038] Figure 1-B A schematic diagram of the structure of another low-temperature starting circuit provided in an embodiment of the present application.

[0039] Figure 2-A This is a structural schematic diagram of a low-temperature starting circuit provided in Example 1.

[0040] Figure 2-B This is a schematic diagram of the structure of another low-temperature starting circuit provided in Example 1.

[0041] Figure 3 This is a structural schematic diagram of a low-temperature starting circuit provided in Example 2.

[0042] Figure 4 This is a structural schematic diagram of a low-temperature starting circuit provided in Example 3.

[0043] Figure 5 This is a structural schematic diagram of a low-temperature starting circuit provided in Example 4.

[0044] Figure 6 This is a structural schematic diagram of a low-temperature starting circuit provided in Example 5.

[0045] Figure 7 A schematic flow chart of a low-temperature startup method provided in an embodiment of the present application.

[0046] Figure 8 A schematic diagram of the structure of a display panel provided in an embodiment of the present application.

[0047] Description of Figure Numbers:

[0048] 110: Temperature sensing circuit

[0049] 120: Switching circuit

[0050] 130: Heating control circuit

[0051] 140: Heating circuit

[0052] VCC1: First power supply

[0053] VCC2: Second power supply

[0054] 131: Logic operation circuit

[0055] R0: Thermistor

[0056] R1: First resistor

[0057] R2: Second resistor

[0058] R3: The third resistor

[0059] R4: Heating resistor

[0060] Q1: The first switch

[0061] Q2: The second switch tube

[0062] Q3: The third switch tube

[0063] N1: First node

[0064] G: Gate

[0065] D: Drain

[0066] S: Source

[0067] 810: Shell

[0068] 820: Main circuit board

[0069] 830: Low temperature starting circuit DETAILED DESCRIPTION

[0070] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0071] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0072] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0073] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0074] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0075] Figure 1-A and Figure 1-B The low temperature starting circuit is applied to a display panel and includes at least a temperature sensing circuit 110 , a switch circuit 120 , a heating control circuit 130 and a heating circuit 140 . Figure 1-A and Figure 1-B Different ways of forming a loop by the first power source VCC1, the switch circuit 120, and the heating control circuit 130 are respectively shown.

[0076] The temperature sensing circuit 110 is used to divide the voltage of the first power source VCC1 according to the temperature of the internal circuit of the display panel and output a temperature sensing signal.

[0077] The low temperature startup circuit can be integrated inside the display panel, specifically, it can be adjacent to the internal circuit of the display panel that has a high startup temperature requirement. Due to the change in the temperature of the internal circuit of the display panel, the temperature sensing circuit 110 can output temperature sensing signals with different voltage amplitudes. In a specific implementation, the temperature sensing circuit 110 can divide the first power supply VCC1 through a temperature-sensitive resistor whose resistance changes with temperature.

[0078] The switch circuit 120 has a first control terminal connected to the output terminal of the temperature sensing circuit 110 and is used for opening or closing under the control of the temperature sensing signal.

[0079] When the amplitude of the temperature sensing signal is greater than or equal to the conduction threshold of the switch circuit 120 , the switch circuit 120 is closed; when the amplitude of the temperature sensing signal is less than the conduction threshold of the switch circuit 120 , the switch circuit 120 is opened.

[0080] The heating control circuit 130, the first power supply VCC1, and the switch circuit 120 form a loop for outputting a first heating control signal at a first node N1 of the loop. Figure 1-A and Figure 1-B As shown, the first node N1 in the loop is located between the switch circuit 120 and the heating control circuit 130. In order to convert the temperature sensing signal into a signal for controlling the operation of the heating circuit, the embodiment of the present application generates a first heating control signal through the switch circuit and the heating control circuit. The switch circuit is opened or closed according to the temperature sensing signal, and accordingly, the first heating control signal of the first node in the loop also changes with the temperature sensing signal. When the temperature of the internal circuit of the display panel is less than the lower limit of the operating temperature of the internal circuit of the display panel, the first heating control signal controls the heating circuit 140 to heat the internal circuit of the display panel.

[0081] The heating circuit 140 is connected to the first node N1 of the heating control circuit 130, and is used to heat the internal circuit of the display panel under the control of the first heating control signal to start the display panel if the temperature is lower than the first preset temperature. The first preset temperature is the lower limit of the operating temperature of the internal circuit of the display panel. When the temperature of the internal circuit of the display panel is lower than the first preset temperature, the internal circuit of the display panel cannot be started.

[0082] In the embodiment of the present application, a temperature sensing circuit first generates a temperature sensing signal according to the temperature of the internal circuit of the display panel, and then converts the temperature sensing signal into a first heating control through a switching circuit and a heating control circuit, thereby controlling the heating circuit to heat the internal circuit of the display panel so that the display panel can start at low temperature.

[0083] The structure of the low temperature starting circuit is further described below through Embodiment 1, Embodiment 2, Embodiment 3 and Embodiment 4.

[0084] Embodiment 1

[0085] Figure 2-A and Figure 2-B The schematic diagrams of the structure of a low temperature starting circuit provided in the embodiments of the present application are shown in the figure. Figure 1-A and Figure 1-B Based on this, the heating control circuit 130 further includes:

[0086] The logic operation circuit 131 has a first input terminal connected to the start signal output terminal of the display panel, a second input terminal connected to the first node N1 of the loop, and an output terminal connected to the heating circuit 140, and is used to perform a logic operation on the start signal of the display panel and the first heating control signal, and output a second heating control signal.

[0087] Correspondingly, the heating circuit is connected to the output end of the logic operation circuit, and is used to heat the display panel under the control of the second heating control signal if the temperature is lower than the first preset temperature, so as to start the display panel.

[0088] In this embodiment, the display panel also outputs a start signal through the start signal output terminal, which is used to indicate whether the display panel is started.

[0089] For example, the start signal is a high-level signal before the display panel is started, and changes to a low-level signal after the display panel is started. The logic operation circuit 131 can use an AND gate circuit. When the internal temperature of the display panel is lower than the first preset temperature, the first heating control signal is a high-level signal, and the start signal output terminal outputs a high-level signal, then the second heating control signal is a high-level signal, and the heating circuit heats the internal circuit of the display panel; when the internal temperature of the display panel is greater than or equal to the second preset temperature (the second preset temperature is greater than or equal to the first preset temperature, and does not exceed the upper limit of the operating temperature of the display panel), or the start signal output terminal outputs a low-level signal, then the second heating control signal is a low-level signal, and the heating circuit stops heating the internal circuit of the display panel.

[0090] For example, the start signal is a low level signal before the display panel is started, and changes to a high level signal after the display panel is started. The logic operation circuit 131 can perform a negation operation on the start signal and then perform a logical AND operation on the start signal after the negation operation and the first heating control signal.

[0091] This embodiment dually controls the heating of the heating circuit through the first heating control signal and the display panel start signal, thereby preventing the heating circuit from still heating the internal circuit of the display panel after the display panel is started, saving energy while avoiding damage to the internal circuit of the display panel caused by prolonged heating.

[0092] Embodiment 2

[0093] exist Figure 1-B On the basis of Figure 3 A schematic diagram of a low temperature starting circuit provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, in this embodiment, the temperature sensing circuit 110 may include:

[0094] Thermistor R0, a first end of which is connected to the first power supply VCC1, and a second end of which is an output end of the temperature sensing circuit;

[0095] The first resistor R1 has a first end connected to the second end of the thermistor R0 and a second end grounded.

[0096] Thermistor is a sensor resistor whose resistance value changes with temperature. According to the temperature coefficient, it is divided into positive temperature coefficient thermistor (PTC thermistor, i.e. Positive Temperature Coefficient thermistor) and negative temperature coefficient thermistor (NTC thermistor, i.e. Negative Temperature Coefficient thermistor). The resistance value of the positive temperature coefficient thermistor increases with the increase of temperature, while the resistance value of the negative temperature coefficient thermistor decreases with the increase of temperature. The materials of thermistor can generally be divided into three categories: semiconductor, metal and alloy.

[0097] Further, the thermistor R0 may be a negative temperature coefficient thermistor, and the switch circuit 120 may include:

[0098] The first switch tube Q1 has a gate G connected to the output end of the temperature sensing circuit 110, a drain D connected to the first node N1 of the loop, and a source S connected to ground, and is used to be disconnected when the temperature is lower than the first preset temperature and closed when the temperature is higher than the second preset temperature.

[0099] The heating control circuit 130 may include:

[0100] The second resistor R2 has a first end connected to the first node of the loop and to the drain of the first switch tube Q1 , and a second end connected to the first power source VCC1 .

[0101] It should be noted that the second resistor can be composed of a single resistor or a plurality of resistors connected in series or in parallel, which is not limited here.

[0102] The heating circuit 140 may include:

[0103] A third switch tube Q3, a control end of the third switch tube is connected to the first node of the loop, and is used to be opened or closed under the control of the first heating control signal;

[0104] The heating resistor R4 forms a loop with the second power supply VCC2 and the third switch tube Q3, and is used to heat the display panel when the third switch tube Q3 is closed.

[0105] Since the thermistor can be a negative temperature coefficient thermistor, its resistance is large at low temperature, that is, when the temperature of the internal circuit of the display panel is less than the first preset temperature, so the gate of the first switch tube Q1 is at a low level, and the first switch tube Q1 is turned off. When the temperature of the internal circuit of the display panel is greater than or equal to the second preset temperature at high temperature, the resistance is small, so the gate of the first switch tube Q1 is at a high level, and the first switch tube Q1 is turned on.

[0106] The second resistor R2 is connected in series between the first power supply VCC1 and the drain of the first switch tube Q1, and the drain of the first switch tube Q1 is used as the first node of the loop to output the first heating control signal. When the internal temperature of the display panel is lower than the first preset temperature, the first heating control signal with a high level is output. When the internal temperature of the display panel is greater than or equal to the second preset temperature, the first heating control signal with a low level is output.

[0107] In a specific implementation, the second power source VCC2 may be the same as the first power source VCC1 to save circuit cost and reduce the number of signal lines in the display panel.

[0108] It should be noted that Figure 3 The first switch tube Q1 and the third switch tube Q3 are N-type switch tubes, which are turned on when the gate is at a high level and turned off when the gate is at a low level. In a specific implementation, the first switch tube Q1 can also be a P-type switch tube, and the third switch tube Q3 is an N-type switch tube. At low temperatures, the P-type first switch tube Q1 is turned on, and at high temperatures, the P-type first switch tube Q1 is turned off.

[0109] and Figure 1-A Correspondingly, in the connection relationship between the P-type first switch tube Q1 and the second resistor R2, the source of the P-type first switch tube Q1 can be connected to the first power source VCC1, the drain of the P-type first switch tube Q1 (as the first node of the loop) is connected to one end of the second resistor R2, and the other end of the second resistor R2 is grounded, that is, the switch circuit 120 is connected in series between the first power source VCC1 and the heating control circuit 130. At low temperatures, the gate of the P-type first switch tube Q1 is at a low level, the P-type first switch tube Q1 is turned on, the first heating control signal output from the first node is at a high level, and the heating circuit is controlled to heat the internal circuit of the display panel. At high temperatures, the gate of the P-type first switch tube Q1 is at a high level, the P-type first switch tube Q1 is turned off, the first heating control signal output from the first node is at a low level, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0110] In this embodiment, a negative temperature coefficient thermistor is first used to generate a temperature sensing signal according to the temperature of the internal circuit of the display panel, and then the temperature sensing signal is converted into a first heating control through a loop composed of a switch tube and a resistor, thereby controlling the heating circuit to heat the internal circuit of the display panel so that the display panel can start at a low temperature.

[0111] Embodiment 3

[0112] As shown above, the thermistor can also be a positive temperature coefficient thermistor. Figure 1-A as well as Figure 3 On the basis of Figure 4 A schematic diagram of a low temperature starting circuit provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, the connection method of the thermistor and the first resistor R1 in the temperature sensing circuit 110 in this embodiment is similar to Figure 3 Similarly, the connection method of each element in the heating circuit 140 is the same as Figure 3 The same, but the switch circuit 120 and the heating control circuit 130 in this embodiment are connected in a manner similar to Figure 3 Differently, the switch circuit 120 in this embodiment includes:

[0113] The second switch tube Q2 has a gate G connected to the output end of the temperature sensing circuit 110, a source S connected to the first node of the loop, and a drain D connected to the first power supply VCC1, and is used to close when the temperature is lower than the first preset temperature and open when the temperature is higher than the second preset temperature.

[0114] The heating control circuit 130 includes:

[0115] The third resistor R3 has a first end connected to the first node N1 of the loop, ie, connected to the drain of the second switch tube Q2, and a second end grounded.

[0116] Since the thermistor R0 in this embodiment can be a positive temperature coefficient thermistor, when the temperature of the internal circuit of the display panel is low, that is, when the temperature is lower than the first preset temperature, the resistance of the thermistor R0 is small, so the gate of the second switch tube Q2 is high level, and the second switch tube Q2 is turned on; when the temperature of the internal circuit of the display panel is higher than or equal to the second preset temperature, the resistance of the thermistor R0 is large, so the gate of the second switch tube Q2 is low level, and the second switch tube Q2 is turned off.

[0117] The third resistor R3 is connected in series between the drain D of the second switch tube Q2 and the ground terminal, and the drain D of the second switch tube Q2 is used as the first node N1 of the loop to output the first heating control signal. When the internal temperature of the display panel is lower than the first preset temperature, the first heating control signal with a high level is output. When the internal temperature of the display panel is greater than or equal to the second preset temperature, the first heating control signal with a low level is output.

[0118] It should be noted that Figure 4The second switch tube Q2 and the third switch tube Q3 are N-type switch tubes, which are turned on when the gate is at a high level and turned off when the gate is at a low level. In a specific implementation, the second switch tube Q2 can also be a P-type switch tube, and the third switch tube Q3 is an N-type switch tube. At low temperatures, the P-type second switch tube Q2 is turned off, and at high temperatures, the P-type second switch tube Q2 is turned on.

[0119] and Figure 1-B Correspondingly, in the connection relationship between the P-type second switch tube Q2 and the third resistor R3, the third resistor R3 can be connected in series between the first power supply VCC1 and the source of the P-type second switch tube Q2 (as the first node of the loop), and the drain of the second switch tube Q2 is grounded. At low temperatures, the gate of the P-type second switch tube Q2 is at a high level, the P-type second switch tube Q2 is turned off, the first heating control signal output by the first node N1 is at a high level, and the heating circuit is controlled to heat the internal circuit of the display panel. At high temperatures, the gate of the P-type second switch tube Q2 is at a low level, the P-type second switch tube Q2 is turned on, the first heating control signal output by the first node N1 is at a low level, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0120] In this embodiment, a positive temperature coefficient thermistor is first used to generate a temperature sensing signal according to the temperature of the internal circuit of the display panel, and then the temperature sensing signal is converted into a first heating control through a loop composed of a switch tube and a resistor, thereby controlling the heating circuit to heat the internal circuit of the display panel so that the display panel can start at low temperature.

[0121] Embodiment 4

[0122] Combining the first embodiment and the second embodiment, Figure 5 A schematic diagram of a low temperature starting circuit provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, in this implementation, Figure 3 On the basis of, in this embodiment, the heating control circuit 130 adds a logic operation circuit 131, and the logic operation circuit 131 is further an AND gate circuit, a first input end of the AND gate circuit is connected to the first node N1, a second input end is connected to the start signal output end of the display panel, and an output end is connected to the gate of the third switch tube Q3.

[0123] In this embodiment, the start-up signal outputted before the display panel is started is a high-level signal, and changes to a low-level signal after the display panel is started. Figure 3The working principle of the low-temperature start-up circuit shown is similar. When the internal temperature of the display panel is lower than the first preset temperature, since the thermistor R0 is a negative temperature coefficient thermistor, at low temperature, that is, when the temperature of the internal circuit of the display panel is lower than the first preset temperature, the resistance of the thermistor R0 is relatively large. Therefore, the gate of the first switch tube Q1 is at a low level, and the first switch tube Q1 is cut off. When the internal circuit temperature of the display panel is higher than or equal to the second preset temperature at high temperature, the resistance is relatively small. Therefore, the gate of the first switch tube Q1 is at a high level, and the first switch tube Q1 is turned on. The first node N1 outputs a high-level first heating control signal. The level of the first node N1, that is, the first heating control signal, is a high-level signal. At the same time, the start signal output end outputs a high-level signal. After the logic AND operation, the second heating control signal is a high-level signal, and the heating circuit is controlled to heat the internal circuit of the display panel.

[0124] When the internal temperature of the display panel is greater than or equal to the second preset temperature (the second preset temperature is greater than or equal to the first preset temperature and does not exceed the upper limit of the operating temperature of the display panel), the resistance of the thermistor R0 is small, the first switch tube Q1 is turned on, and the first node N1 outputs a low-level first heating control signal. At this time, the start signal output terminal outputs a low-level signal, and the second heating control signal is a low-level signal after a logic AND operation, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0125] Or the first node N1 outputs a high-level first heating control signal, but the start signal output terminal outputs a low-level signal, indicating that the display panel has been started and there is no need to heat the display panel. At this time, after the logic AND operation, the second heating control signal is a low-level signal, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0126] This embodiment dually controls the heating of the heating circuit through the first heating control signal output by the first node N1 and the start signal output by the display panel, thereby preventing the heating circuit from still heating the internal circuit of the display panel after the display panel is started, saving energy while avoiding damage to the internal circuit of the display panel caused by long-term heating.

[0127] Embodiment 5

[0128] In combination with Embodiment 1 and Embodiment 3, Figure 6 A schematic diagram of a low temperature starting circuit provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, in this implementation, Figure 4 On the basis of, in this embodiment, the heating control circuit 130 adds a logic operation circuit 131, and the logic operation circuit 131 is further an AND gate circuit, a first input end of the AND gate circuit is connected to the second end of the positive temperature coefficient thermistor R0, a second input end is connected to the start signal output end of the display panel, and an output end is connected to the gate of the third switch tube Q3.

[0129] In this embodiment, the start-up signal outputted before the display panel is started is a high-level signal, and changes to a low-level signal after the display panel is started. Figure 4 The working principle of the low-temperature start-up circuit shown is similar. Since the thermistor R0 in this embodiment can be a positive temperature coefficient thermistor, when the temperature of the internal circuit of the display panel is low, that is, when the temperature is lower than the first preset temperature, the resistance of the thermistor R0 is small. Therefore, the gate of the second switch tube Q2 is high, the second switch tube Q2 is turned on, the first node N1 outputs a high-level first heating control signal, and the start signal output terminal outputs a high-level signal. Then, after the logic AND operation, the second heating control signal is a high-level signal, and the heating circuit is controlled to heat the internal circuit of the display panel.

[0130] When the temperature of the internal circuit of the display panel is greater than or equal to the second preset temperature at high temperature, the resistance of the thermistor R0 is relatively large, so the gate of the second switch tube Q2 is at a low level, the second switch tube Q2 is disconnected, and the first node N1 outputs a low-level first heating control signal. At this time, the start signal output terminal outputs a low-level signal, and the second heating control signal is a low-level signal after a logic AND operation, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0131] Or the first node N1 outputs a high-level first heating control signal, but the start signal output terminal outputs a low-level signal, indicating that the display panel has been started and there is no need to heat the display panel. At this time, after the logic AND operation, the second heating control signal is a low-level signal, and the heating circuit is controlled to stop heating the internal circuit of the display panel.

[0132] Based on the above low temperature startup circuit, the embodiment of the present application further provides a low temperature startup method for a display panel. Figure 7 A schematic diagram of a low temperature startup method provided in an embodiment of the present application is shown in FIG. Figure 7 As shown, the method includes at least the following steps.

[0133] Step 710: Using a temperature sensing circuit to divide the voltage of the first power source according to the temperature of the internal circuit of the display panel to obtain a temperature sensing signal.

[0134] Step 720: When the switch circuit receives the temperature sensing signal, it is opened or closed, and the first control terminal of the switch circuit is connected to the output terminal of the temperature sensing circuit.

[0135] Step 730: A first heating control signal is obtained by forming a loop with the heating control circuit, the first power supply, and the switch circuit.

[0136] Step 740: According to the first heating control signal, when the temperature is lower than the first preset temperature, the internal circuit of the display panel is heated to start the display panel.

[0137] In this embodiment, a temperature sensing circuit generates a temperature sensing signal according to the temperature of the internal circuit of the display panel, and then converts the temperature sensing signal into a first heating control through a loop composed of a switching circuit and a heating control, thereby controlling the heating circuit to heat the internal circuit of the display panel so that the display panel starts at low temperature.

[0138] Furthermore, between step 730 and step 740, a start signal output by the display panel can be received, and a logic operation is performed between the first heating control signal and the start signal. Accordingly, step 740 is changed to heating the internal circuit of the display panel when the temperature is less than the first preset temperature according to the second heating control signal to start the display panel. The heating of the heating circuit is controlled by the first heating control signal and the display panel start signal, so as to avoid the heating circuit still heating the internal circuit of the display panel after the display panel is started, thereby saving energy consumption and avoiding damage to the internal circuit of the display panel caused by prolonged heating.

[0139] Based on the above low temperature start-up circuit, the embodiment of the present application further provides a display panel, Figure 8 A schematic diagram of a low temperature starting circuit provided in an embodiment of the present application is shown in FIG. Figure 8 As shown, it includes a housing 810 , a main circuit board 820 and a low-temperature starting circuit 830 .

[0140] In a specific embodiment, the low temperature start circuit 830 can be arranged in the main circuit board 820, specifically, near the circuit with higher working temperature requirement in the main board circuit, so as to heat it.

[0141] The display panel of the present application may include any product or component with a display function, such as a mobile phone, a tablet computer, a television, a laptop computer, a digital photo frame, a navigator, etc., so that the product or component can be started even in a low temperature environment.

[0142] It should be noted that the display panel also includes other necessary components and components such as an array substrate, an opposing substrate and a liquid crystal layer, and those skilled in the art may make corresponding supplements according to the specific use requirements of the display panel, which will not be elaborated here.

[0143] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into multiple modules or units to be embodied.

[0144] In addition, although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0145] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A low temperature starting circuit, characterized in that: Applied to a display panel, the low temperature start-up circuit comprises: A temperature sensing circuit, used to divide the voltage of the first power supply according to the temperature of the internal circuit of the display panel and output a temperature sensing signal; wherein the temperature sensing circuit includes a thermistor; A switch circuit, wherein the first control end of the switch circuit is connected to the output end of the temperature sensing circuit, and is used to open or close under the control of the temperature sensing signal; the thermistor is a negative temperature coefficient thermistor, and the switch circuit includes: a first switch tube, the gate of which is connected to the output end of the temperature sensing circuit, the drain of which is connected to the first node of the loop, and the source of which is grounded, and is used to open when the temperature is less than a first preset temperature, and close when the temperature is greater than a second preset temperature, and the second preset temperature is greater than or equal to the first preset temperature; A heating control circuit, which forms a loop with the first power supply and the switch circuit, and is used to output a first heating control signal at a first node of the loop; the heating control circuit comprises: a second resistor, a first end of which is connected to the first node of the loop and to the drain of the first switch tube, and a second end of which is connected to the first power supply; A heating circuit is connected to the first node of the heating control circuit and is used to heat the internal circuit of the display panel under the control of the first heating control signal to start the display panel if the temperature is less than a first preset temperature; the heating circuit includes: a third switch tube, a control end of the third switch tube is connected to the first node of the loop and is used to open or close under the control of the first heating control signal; a heating resistor, a second power supply and the third switch tube form a loop, and is used to heat the display panel when the third switch tube is closed.

2. A low temperature starting circuit, characterized in that: Applied to a display panel, the low temperature start-up circuit comprises: A temperature sensing circuit, used to divide the voltage of the first power supply according to the temperature of the internal circuit of the display panel and output a temperature sensing signal; wherein the temperature sensing circuit includes a thermistor; A switch circuit, wherein the first control end of the switch circuit is connected to the output end of the temperature sensing circuit, and is used to open or close under the control of the temperature sensing signal; the thermistor is a positive temperature coefficient thermistor, and the switch circuit includes: a second switch tube, the gate of which is connected to the output end of the temperature sensing circuit, the source of which is connected to the first node of the loop, and the drain of which is connected to the first power supply, and is used to close when the temperature is less than a first preset temperature, and to open when the temperature is greater than a second preset temperature, and the second preset temperature is greater than or equal to the first preset temperature; A heating control circuit, which forms a loop with the first power supply and the switch circuit, and is used to output a first heating control signal at a first node of the loop; the heating control circuit comprises: a third resistor, a first end of which is connected to the first node of the loop, connected to the drain of the second switch tube, and a second end of which is grounded; A heating circuit is connected to the first node of the heating control circuit and is used to heat the internal circuit of the display panel under the control of the first heating control signal to start the display panel if the temperature is less than a first preset temperature; the heating circuit includes: a third switch tube, a control end of the third switch tube is connected to the first node of the loop and is used to open or close under the control of the first heating control signal; a heating resistor, a second power supply and the third switch tube form a loop, and is used to heat the display panel when the third switch tube is closed.

3. The low temperature starting circuit according to claim 1 or 2, characterized in that: The heating control circuit also includes: a logic operation circuit, wherein a first input terminal is connected to the start signal output terminal of the display panel, a second input terminal is connected to the first node of the loop, and an output terminal is connected to the heating circuit, and is used to perform a logic operation on the start signal of the display panel and the first heating control signal, and output a second heating control signal; The heating circuit is connected to the output end of the logic operation circuit, and is used for heating the display panel under the control of the second heating control signal to start the display panel if the temperature is lower than the first preset temperature.

4. The low temperature starting circuit according to claim 1 or 2, characterized in that: The temperature sensing circuit comprises: a thermistor, a first end of which is connected to the first power source and a second end of which is an output end of the temperature sensing circuit; The first resistor has a first end connected to the second end of the thermistor and a second end grounded.

5. A method for starting a display panel at low temperature, characterized in that: Applied to the low temperature starting circuit according to any one of claims 1 to 4, the method comprises: The temperature sensing circuit divides the voltage of the first power supply according to the temperature of the internal circuit of the display panel to obtain a temperature sensing signal; When the switch circuit receives the temperature sensing signal, it opens or closes, and the first control end of the switch circuit is connected to the output end of the temperature sensing circuit; A first heating control signal is obtained by forming a loop through the heating control circuit, the first power supply and the switch circuit; According to the first heating control signal, when the temperature is less than a first preset temperature, the internal circuit of the display panel is heated to start the display panel.

6. A display panel, characterized in that: It comprises a housing, a main circuit board and a low-temperature starting circuit as described in any one of claims 1 to 4.

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