Driving circuit, display module and display system

Abstract

The utility model relates to a driving circuit, a display module and a display system. The driving circuit comprises a common anode driving group and a common cathode driving group. The common-anode driving group and the common-cathode driving group are connected in series; the common anode driving group is provided with M first driving ends; the common-cathode driving group is provided with M second driving ends; the first driving end is used for being connected with the cathodes of all the LEDs on the corresponding columns in the first LED array and performing display control on the LEDs on the corresponding columns in the first LED array; and the second driving end is used for being connected with the anodes of all the LEDs on the corresponding columns in the second LED array and carrying out display control on the LEDs on the corresponding columns in the second LED array. The common anode driving group and the common cathode driving group are connected in series, so that voltage distribution between each LED array and the driving circuit can be effectively balanced, potential safety hazards such as overheating caused by overlarge voltage difference can be effectively avoided, and the safety of the driving circuit is effectively improved.

Description

Technical Field

[0001] This application relates to the field of display driver technology, and in particular to a driver circuit, display module, and display system. Background Technology

[0002] With the continuous advancement of LED display technology, the requirements for driver circuits are also increasing. Under normal operating conditions, LEDs of different colors exhibit different on-state voltage drops, with red LEDs exhibiting the smallest on-state voltage drop. Since the driver circuit and LEDs are typically powered by the same source, and the driver circuit requires a relatively high voltage to operate normally, this can lead to potential safety hazards in the driver circuit corresponding to red LEDs.

[0003] There is currently no effective solution to the problem of low safety in existing drive circuits. Utility Model Content

[0004] Therefore, it is necessary to provide an LED display device and an LED display system to address the aforementioned technical problems.

[0005] In a first aspect, this application provides a driving circuit, which includes a common anode driving group and a common cathode driving group; the common anode driving group and the common cathode driving group are connected in series; the common anode driving group has M first driving terminals; the common cathode driving group has M second driving terminals; wherein M is a natural number greater than 0;

[0006] The first driving terminal is used to connect to the cathode of all LEDs in the corresponding column of the first LED array, and to perform display control on the LEDs in the corresponding column of the first LED array;

[0007] The second driving terminal is used to connect to the anode of all LEDs in the corresponding column of the second LED array, and to perform display control on the LEDs in the corresponding column of the second LED array.

[0008] In one embodiment, the common anode drive group includes M first constant current sources; the common cathode drive group includes M second constant current sources;

[0009] The first ends of the M first constant current sources are used to connect to the cathodes of all LEDs in the corresponding column of the first LED array; the second ends of the M first constant current sources are connected in parallel to each other to the first connection point.

[0010] The first ends of the M second constant current sources are connected in parallel to each other to the second connection point; the second ends of the M second constant current sources are used to connect to the anodes of all LEDs in the corresponding column of the second LED array.

[0011] The first connection point and the second connection point are connected in series.

[0012] In one embodiment, the driving circuit further includes a current compensation circuit;

[0013] The first terminal of the current compensation circuit is connected to the power supply, the second terminal of the current compensation circuit is connected to the connection point of the common anode drive group and the common cathode drive group, and the third terminal of the current compensation circuit is grounded; the current compensation circuit is used to perform current compensation on the drive circuit.

[0014] In one embodiment, the current compensation circuit includes a first bypass circuit and a second bypass circuit;

[0015] The first terminal of the first bypass circuit is used to connect to the power supply, and the second terminal of the first bypass circuit is connected to the connection point of the common anode drive group and the common cathode drive group.

[0016] The first terminal of the second bypass circuit is connected to the connection point of the common anode drive group and the common cathode drive group, and the second terminal of the second bypass circuit is grounded.

[0017] In one embodiment, the first bypass circuit includes a first switch; the second bypass circuit includes a second switch;

[0018] The first switch is used to turn the first bypass circuit on or off;

[0019] The second switch is used to turn the second bypass circuit on or off.

[0020] Secondly, this application also provides a display module, the display module including a first LED array, a second LED array, and the driving circuit described in any of the embodiments of the first aspect above; the driving circuit includes a common anode driving group and a common cathode driving group; the common anode driving group has M first driving terminals; the common cathode driving group has M second driving terminals; the first LED array includes N×M LEDs; the second LED array includes N×M LEDs; wherein N and M are both natural numbers greater than 0;

[0021] The cathodes of the N LEDs corresponding to the m-th column of the first LED array are connected to the m-th first driving terminal of the common anode driving group; where 0 < m ≤ M, and m is a natural number;

[0022] The anodes of the N LEDs corresponding to the m-th column of the second LED array are connected to the m-th second driving terminal of the common cathode driving group.

[0023] In one embodiment, the LED is a red LED.

[0024] In one embodiment, the display module further includes N first switching circuits, N second switching circuits, and N scan signal lines;

[0025] The first terminal of the nth first switch circuit is connected to the anode of the M LEDs corresponding to the nth row of the first LED array; the second terminal of the nth first switch circuit is connected to the power supply; the third terminal of the nth first switch circuit is connected to the nth scan signal line; the first switch circuit is used to start or stop providing power to the M LEDs corresponding to the nth row of the first LED array according to the scan signal transmitted by the nth scan signal line; where 0 < n ≤ N, and n is a natural number;

[0026] The first terminal of the nth second switch circuit is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array; the second terminal of the nth second switch circuit is connected to the nth scan signal line; the third terminal of the nth second switch circuit is grounded; the second switch circuit is used to start or stop providing power to the M LEDs corresponding to the nth row of the second LED array according to the scan signal transmitted by the nth scan signal line.

[0027] In one embodiment, the first switching circuit includes a first switching transistor;

[0028] The drain of the nth first switch is connected to the anode of the M LEDs corresponding to the nth row of the first LED array; the source of the nth first switch is connected to the power supply; and the gate of the nth first switch is connected to the nth scan signal line.

[0029] In one embodiment, the second switching circuit includes a second switching transistor and logic circuitry;

[0030] The input terminal of the nth logic circuit is connected to the nth scan signal line, and the output terminal of the nth logic circuit is connected to the gate of the nth second switch.

[0031] The source of the nth second switch is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array; the drain of the nth second switch is grounded.

[0032] In one embodiment, the first switch is a PMOS transistor.

[0033] The second switch is an NMOS transistor.

[0034] In one embodiment, the logic circuit includes an inverter.

[0035] Thirdly, this application also provides a display system, which includes a main control circuit, a power supply, and at least one display module as described in any of the embodiments of the second aspect above;

[0036] The main control circuit and the power supply are connected to the display module.

[0037] The aforementioned driving circuit, display module, and display system include a common anode driving group and a common cathode driving group. The common anode driving group and the common cathode driving group are connected in series. The common anode driving group has M first driving terminals, and the common cathode driving group has M second driving terminals. The first driving terminals are used to connect to the cathodes of all LEDs in the corresponding column of the first LED array to control the display of the LEDs in the corresponding column of the first LED array. The second driving terminals are used to connect to the anodes of all LEDs in the corresponding column of the second LED array to control the display of the LEDs in the corresponding column of the second LED array. By connecting the common anode driving group and the common cathode driving group in series, the voltage distribution between each LED array and the driving circuit can be effectively balanced, which can effectively avoid safety hazards such as overheating caused by excessive voltage differences and effectively improve the safety of the driving circuit. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of a driving circuit in one embodiment;

[0040] Figure 2 This is a schematic diagram of the driving circuit in a specific embodiment;

[0041] Figure 3 This is a schematic diagram of the drive circuit in another embodiment;

[0042] Figure 4 This is a schematic diagram of the driving circuit in another specific embodiment;

[0043] Figure 5 This is a schematic diagram of a display module in one embodiment;

[0044] Figure 6 This is a schematic diagram of a display module in a specific embodiment;

[0045] Figure 7 This is a schematic diagram of the display module in another specific embodiment;

[0046] Figure 8 This is a schematic diagram of a display module in a display system according to one embodiment.

[0047] Explanation of reference numerals in the attached figures:

[0048] 100. Driving circuit; 110. Common anode driving group; 120. Common cathode driving group; 130. Current compensation circuit; 131. First bypass circuit; 132. Second bypass circuit; 200. First LED array; 300. Second LED array; 400. First switching circuit; 500. Second switching circuit. Detailed Implementation

[0049] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0050] In existing technologies, monochrome LED displays typically use a common-anode driving method. When the LEDs are operating normally, different colored LEDs have different on-state voltage drops, with red LEDs having a smaller on-state voltage drop, typically around 1.8V to 2.8V. Since the driving circuit and LEDs are usually powered by the same source, and the voltage required for normal operation of the driving circuit is relatively high, generally exceeding the on-state voltage drop of the red LED, this can lead to overheating and voltage waste in the driving circuit corresponding to the red LED, potentially causing LED display malfunctions and affecting display quality. Therefore, this embodiment aims to provide a driving circuit to solve the problems existing in the prior art.

[0051] In one embodiment, such as Figure 1 As shown, Figure 1 This is a schematic diagram of a driving circuit in one embodiment; the driving circuit 100 includes a common anode driving group 110 and a common cathode driving group 120; the common anode driving group 110 and the common cathode driving group 120 are connected in series; the common anode driving group 110 has M first driving terminals; the common cathode driving group 120 has M second driving terminals; where M is a natural number greater than 0;

[0052] The first driving terminal is used to connect to the cathode of all LEDs in the corresponding column of the first LED array (not shown in the figure) to perform display control on the LEDs in the corresponding column of the first LED array;

[0053] The second driving terminal is used to connect to the anode of all LEDs in the corresponding column of the second LED array (not shown in the figure) to perform display control on the LEDs in the corresponding column of the second LED array.

[0054] Among them, the common anode drive group 110 is used to realize the common anode drive of multiple LEDs; the common cathode drive group 120 is used to realize the common cathode drive of multiple LEDs.

[0055] The first driving terminal is used to transmit corresponding driving current to the LEDs in the corresponding columns of the first LED array according to preset display data, so as to control the LEDs to perform corresponding displays. The second driving terminal is used to transmit corresponding driving current to the LEDs in the corresponding columns of the second LED array according to preset display data, so as to control the LEDs to perform corresponding displays. It should be noted that the preset display data needs to be set according to the actual display requirements, and is not specifically limited here.

[0056] The first LED array includes N×M LEDs; the second LED array includes N×M LEDs; where N and M are both natural numbers greater than 0; both the first and second LED arrays are monochrome LED arrays, and the LEDs are red LEDs; where the on-state voltage drop of the red LEDs ranges from 1.8V to 2.8V.

[0057] It should be noted that the driving circuit 100 is powered by the same circuit as the first LED array and the second LED array.

[0058] For example, the common anode drive group 110 and the common cathode drive group 120 are connected in series. The cathodes of the N LEDs corresponding to the m-th column of the first LED array are connected to the m-th first drive terminal of the common anode drive group 110; the anodes of the N LEDs corresponding to the m-th column of the second LED array are connected to the m-th second drive terminal of the common cathode drive group; where 0 < m ≤ M, and m is a natural number; the common anode drive group 110 is used to drive the first LED array for corresponding display; the common cathode drive group 120 is used to drive the second LED array for corresponding display. When the common anode drive group 110, the common cathode drive group 120, the first LED array, and the second LED array are powered by the same power supply, by connecting the common anode drive group 110 and the common cathode drive group 120 in series, the voltage distribution among the common anode drive group 110, the common cathode drive group 120, the first LED array, and the second LED array can be effectively balanced, ensuring the effective use of the power supply, reducing voltage waste, and avoiding the risk of overheating and damage caused by excessive voltage differences.

[0059] In this embodiment, by connecting the common anode drive group 110 and the common cathode drive group 120 in series, the voltage distribution between each LED array and the drive circuit 100 can be effectively balanced, which can effectively avoid safety hazards such as overheating caused by excessive voltage difference and effectively improve the safety of the drive circuit 100.

[0060] In one embodiment, such as Figure 2 As shown, Figure 2This is a schematic diagram of a driving circuit in a specific embodiment; the common anode driving group 110 includes M first constant current sources; the common cathode driving group 120 includes M second constant current sources;

[0061] The first ends of the M first constant current sources are used to connect to the cathodes of all LEDs in the corresponding column of the first LED array (not shown in the figure); the second ends of the M first constant current sources are connected in parallel to each other to the first connection point a;

[0062] The first ends of the M second constant current sources are connected in parallel to each other to the second connection point b; the second ends of the M second constant current sources are used to connect to the anodes of all LEDs in the corresponding column of the second LED array (not shown in the figure);

[0063] The first connection point a and the second connection point b are connected in series.

[0064] The first constant current source is used to adjust the on / off state of the first constant current source according to the first preset display data, so as to realize the display control of the LEDs on the corresponding column of the first LED array.

[0065] The second constant current source is used to adjust the on / off state of the second constant current source according to the second preset display data, so as to realize the display control of the LEDs on the corresponding column of the second LED array.

[0066] It should be noted that both the first and second preset display data need to be set according to actual display requirements, and no specific restrictions are made here.

[0067] For example, when the first LED array includes N×M LEDs and the second LED array includes N×M LEDs, the first ends of the M first constant current sources are respectively connected to the cathodes of all LEDs in the corresponding columns of the first LED array; the second ends of the M first constant current sources are connected in parallel to the first connection point a; the first ends of the M second constant current sources are connected in parallel to the second connection point b; the second ends of the M second constant current sources are respectively connected to the anodes of all LEDs in the corresponding columns of the second LED array; the first connection point a and the second connection point b are connected in series. Based on this, when the common anode drive group 110, the common cathode drive group 120, the first LED array, and the second LED array are powered by the same power supply, the display control of the LEDs in the corresponding columns of the first LED array can be performed through the M first constant current sources, and the display control of the LEDs in the corresponding columns of the first LED array can be performed through the M second constant current sources. At the same time, the balance and rationality of the power supply voltage distribution can be ensured, effectively avoiding safety hazards such as overheating caused by excessive voltage differences.

[0068] In this embodiment, based on the first constant current source and the second constant current source, a reliable driving current can be provided to the first LED array and the second LED array, so as to ensure that the first LED array and the second LED array can be accurately controlled to perform corresponding displays, thereby improving the reliability of the driving circuit 100.

[0069] In one embodiment, Figure 3 This is a schematic diagram of a drive circuit in another embodiment; the drive circuit 100 also includes a current compensation circuit 130;

[0070] The first terminal of the current compensation circuit 130 is connected to the power supply VCC, the second terminal of the current compensation circuit 130 is connected to the connection point of the common anode drive group 110 and the common cathode drive group 120, and the third terminal of the current compensation circuit 130 is grounded; the current compensation circuit 130 is used to perform current compensation on the drive circuit 100.

[0071] The current compensation circuit 130 is used to compensate the current of the drive circuit 100, ensuring the balance of current distribution between the common anode drive group 110 and the common cathode drive group 120. For example, when the number of LEDs lit in the common anode drive group 110 and the common cathode drive group 120 at the same time is unequal, it will cause inconsistency in the current of the common anode drive group 110 and the common cathode drive group 120. Based on the current compensation circuit 130, the current distribution between the common anode drive group 110 and the common cathode drive group 120 can be effectively balanced, ensuring that both the common anode drive group 110 and the common cathode drive group 120 can operate normally.

[0072] The power supply VCC is a DC power supply. The voltage value of the power supply VCC needs to be set according to the performance of the driving circuit 100 and the performance of the LEDs in the first LED array and the second LED array, and is not specifically limited here; for example, the power supply VCC is equal to 5V.

[0073] In this embodiment, based on the current compensation circuit 130, the balance of current distribution between the common anode drive group 110 and the common cathode drive group 120 can be ensured, laying the foundation for further improving the reliability of the drive circuit 100.

[0074] In one embodiment, such as Figure 4 As shown, Figure 4 This is a schematic diagram of the driving circuit in another specific embodiment; the current compensation circuit 130 includes a first bypass circuit 131 and a second bypass circuit 132;

[0075] The first terminal of the first bypass circuit 131 is connected to the power supply VCC, and the second terminal of the first bypass circuit 131 is connected to the connection point of the common anode drive group 110 and the common cathode drive group 120.

[0076] The first terminal of the second bypass circuit 132 is connected to the connection point of the common anode drive group 110 and the common cathode drive group 120, and the second terminal of the second bypass circuit 132 is grounded.

[0077] The first bypass circuit 131 has a conducting characteristic; the state of the first bypass circuit 131 includes a conducting state and a turning-off state; the second bypass circuit 132 has a conducting characteristic; the state of the second bypass circuit 132 includes a conducting state and a turning-off state.

[0078] For example, when the number of LEDs lit in the common anode drive group 110 is equal to the number of LEDs lit in the common cathode drive group 120 at the same time, both the first bypass circuit 131 and the second bypass circuit 132 are controlled to be in the off state; when the number of LEDs lit in the common anode drive group 110 is less than the number of LEDs lit in the common cathode drive group 120 at the same time, the first bypass circuit 131 is controlled to be in the on state and the second bypass circuit 132 is controlled to be in the off state to ensure that a normal current loop can be formed; when the number of LEDs lit in the common anode drive group 110 is greater than the number of LEDs lit in the common cathode drive group 120 at the same time, the first bypass circuit 131 is controlled to be in the off state and the second bypass circuit 132 is controlled to be in the on state to ensure that excess current can be bypassed. Based on this, by using the first bypass circuit 131 and the second bypass circuit 132, even when the number of LEDs lit by the common anode drive group 110 and the number of LEDs lit by the common cathode drive group 120 are inconsistent at the same time, it can be ensured that the drive circuit 100 can form a normal current loop, thereby improving the balance of current distribution inside the drive circuit 100.

[0079] In an exemplary embodiment, the first bypass circuit 131 includes a first switch; the second bypass circuit 132 includes a second switch; the first switch is used to turn the first bypass circuit 131 on or off; the second switch is used to turn the second bypass circuit 132 on or off.

[0080] It should be noted that the first switch may include, but is not limited to, an electronic switch; wherein, the electronic switch may include, but is not limited to, a switching transistor.

[0081] In this embodiment, based on the conduction characteristics of the first bypass circuit 131 and the second bypass circuit 132, even when the number of LEDs lit by the common anode drive group 110 and the number of LEDs lit by the common cathode drive group 120 are inconsistent at the same time, it can ensure that the drive circuit 100 can form a normal current loop, thereby ensuring the balance of current distribution inside the drive circuit 100 and further improving the reliability of the drive circuit 100.

[0082] In one embodiment, such as Figure 5 As shown, Figure 5This is a schematic diagram of a display module in one embodiment; the display module includes a first LED array 200, a second LED array 300, and a driving circuit 100 as described in any of the above embodiments; the driving circuit 100 includes a common anode driving group 110 and a common cathode driving group 120; the common anode driving group 110 has M first driving terminals; the common cathode driving group 120 has M second driving terminals; the first LED array 200 includes N×M LEDs; the second LED array 300 includes N×M LEDs; wherein N and M are both natural numbers greater than 0;

[0083] The cathodes of the N LEDs corresponding to the m-th column of the first LED array 200 are connected to the m-th first driving terminal of the common anode driving group 110; where 0 < m ≤ M, and m is a natural number;

[0084] The anodes of the N LEDs corresponding to the mth column of the second LED array 300 are connected to the mth second driving terminal of the common cathode driving group 120.

[0085] Among them, the LED is a red LED; the on-state voltage drop range of the red LED is 1.8V to 2.8V.

[0086] For example, the cathodes of N LEDs corresponding to the m-th column of the first LED array 200 are connected to the m-th first driving terminal of the common anode driving group 110. The display control of the LEDs corresponding to the m-th column of the first LED array 200 can be performed through the m-th first driving terminal. The anodes of N LEDs corresponding to the m-th column of the second LED array 300 are connected to the m-th second driving terminal of the common cathode driving group 120. The display control of the LEDs corresponding to the m-th column of the second LED array 300 can be performed through the m-th second driving terminal.

[0087] In this embodiment, by connecting the first LED array 200, the driving circuit 100, and the second LED array 300 in series, the voltage distribution among the first LED array 200, the driving circuit 100, and the second LED array 300 can be effectively balanced. This can effectively avoid safety hazards such as overheating caused by excessive voltage differences and effectively improve the safety of the display module.

[0088] In one embodiment, such as Figure 6 As shown, Figure 6 This is a schematic diagram of a display module in a specific embodiment; the display module also includes N first switch circuits 400, N second switch circuits 500, and N scan signal lines Scan;

[0089] The first terminal of the nth first switch circuit 400 is connected to the anode of the M LEDs corresponding to the nth row of the first LED array 200; the second terminal of the nth first switch circuit 400 is connected to the power supply VCC; the third terminal of the nth first switch circuit 400 is connected to the nth scan signal line Scan; the first switch circuit 400 is used to start or stop providing power to the M LEDs corresponding to the nth row of the first LED array 200 according to the scan signal transmitted by the nth scan signal line Scan; where 0 < n ≤ N, and n is a natural number;

[0090] The first terminal of the nth second switch circuit 500 is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array 300; the second terminal of the nth second switch circuit 500 is connected to the nth scan signal line Scan; the third terminal of the nth second switch circuit 500 is grounded; the second switch circuit 500 is used to start or stop providing power to the M LEDs corresponding to the nth row of the second LED array 300 according to the scan signal transmitted by the nth scan signal line Scan.

[0091] The first switching circuit 400 has a conduction characteristic, and the state of the first switching circuit 400 includes a conduction state and a cut-off state; the second switching circuit 500 has a conduction characteristic, and the state of the second switching circuit 500 includes a conduction state and a cut-off state.

[0092] The Scan signal line is used to generate corresponding scan signals according to display requirements; the scan signal is a logic level signal; the scan signal has a valid state and an invalid state.

[0093] For example, when the scan signal transmitted by the nth scan signal line Scan is in an active state, the nth first switch circuit 400 and the nth second switch circuit 500 are controlled to be in an active state to start supplying power to the M LEDs corresponding to the nth row of the first LED array 200 and the M LEDs corresponding to the nth row of the second LED array 300; when the scan signal transmitted by the nth scan signal line Scan is in an inactive state, the nth first switch circuit 400 and the nth second switch circuit 500 are controlled to be in an inactive state to stop supplying power to the M LEDs corresponding to the nth row of the first LED array 200 and the M LEDs corresponding to the nth row of the second LED array 300.

[0094] It should be noted that the correspondence between the scan signal state and the logic level signal needs to be set according to the actual circuit design, and no specific limitation is made here; for example, when the scan signal state is active, the scan signal is a low-level signal; when the scan signal state is inactive, the scan signal is a high-level signal. It should also be noted that only one scan signal line (Scan) can output an active scan signal at any given time.

[0095] For example, assuming the power supply VCC voltage is 5V and the LED is a red LED; when the scan signal transmitted by the nth scan signal line Scan is active at a certain moment, the nth first switch circuit 400 and the nth second switch circuit 500 are both turned on, respectively supplying power to the M LEDs corresponding to the nth row of the first LED array 200 and the M LEDs corresponding to the nth row of the second LED array 300; at this time, according to preset display data, the turn-on time of each first constant current source in the common anode drive group 110 and the turn-on time of each second constant current source in the common cathode drive group 120 are controlled, thereby controlling the display of the LEDs corresponding to the corresponding columns of the first LED array 200 through the M first drive terminals of the common anode drive group 110; and controlling the display of the LEDs corresponding to the corresponding columns of the second LED array 300 through the M second drive terminals of the common cathode drive group 120. It should be noted that the turn-on time refers to the time during which the PWM signal maintains an active level within one cycle. By adjusting the on-time (i.e., duty cycle), the conduction time of the constant current source can be controlled, thereby adjusting the lighting time of the LED.

[0096] Furthermore, since the power supply VCC is 5V and the on-state voltage drop of the red LED is between 1.8V and 2.8V, when the first switching circuit 400 is in the on state, the voltage at each of the M first driving terminals of the common anode driving group 110, i.e., the first driving terminal OUT1 to the first driving terminal OUTM, is between 2V and 3V. Furthermore, since the common anode driving group 110 and the common cathode driving group 120 are connected in series, the M second driving terminals of the common cathode driving group 120, i.e., the second driving terminal OUT1 to the second driving terminal OUTM, use the remaining 2V to 3V voltage at the first driving terminals OUT1 to OUTM of the common anode driving group 110 to perform normal display control on the corresponding columns of LEDs in the second LED array.

[0097] In this embodiment, based on the Scan signal line, corresponding scan signals can be provided to the first switch circuit 400 and the second switch circuit 500 respectively. Then, according to the scan signals, the on / off state of the first switch circuit 400 and the second switch circuit 500 can be accurately controlled so as to supply power to the multiple LEDs corresponding to the corresponding rows of the first LED array 200 and the multiple LEDs corresponding to the corresponding rows of the second LED array 300, ensuring that the LEDs can work normally and effectively improving the reliability of the display module.

[0098] In one embodiment, see Figure 6 The first switching circuit 400 includes a first switching transistor;

[0099] The drain of the nth first switch is connected to the anode of the M LEDs corresponding to the nth row of the first LED array 200; the source of the nth first switch is connected to the power supply VCC; and the gate of the nth first switch is connected to the nth scan signal line Scan.

[0100] The first switch has a conduction characteristic; the state of the first switch includes an on state and an off state; the first switch is a PMOS transistor; for example, when the scan signal is valid, that is, when the scan signal is a low level signal, the first switch is controlled to be in the on state; when the scan signal is invalid, that is, when the scan signal is a high level signal, the first switch is controlled to be in the off state.

[0101] In this embodiment, based on the conduction characteristics of the first switching transistor, the power supply of the first LED array 200 can be accurately controlled, laying the foundation for ensuring the reliability of the display module.

[0102] In one embodiment, see Figure 6 The second switching circuit 500 includes a second switching transistor and logic circuitry.

[0103] The input terminal of the nth logic circuit is connected to the nth scan signal line Scan, and the output terminal of the nth logic circuit is connected to the gate of the nth second switch.

[0104] The source of the nth second switch is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array 300; the drain of the nth second switch is grounded.

[0105] The second switch has conduction characteristics; the state of the second switch includes an on state and an off state; the second switch is an NMOS transistor; the logic circuit includes an inverter, which is used to convert the scan signal so that the on / off state of the second switch can be accurately controlled according to the converted scan signal.

[0106] For example, when the scan signal is in an active state, i.e., when the scan signal is a low-level signal, the scan signal is flipped by the logic circuit, i.e., the inverter, to change the scan signal from a low-level signal to a high-level signal, thereby controlling the second switch to be in the on state; when the scan signal is in an inactive state, i.e., when the scan signal is a high-level signal, the scan signal is flipped by the logic circuit, i.e., the inverter, to change the scan signal from a high-level signal to a low-level signal, thereby controlling the first switch to be in the off state.

[0107] In this embodiment, based on the conduction characteristics of the second switch and the switching characteristics of the logic circuit, the power supply of the second LED array 300 can be accurately controlled, laying the foundation for ensuring the reliability of the display module.

[0108] In another embodiment, see Figure 7 The driving circuit 100 also includes a first bypass circuit 131 and a second bypass circuit 132. When the number of LEDs lit by the common anode driving group 110 is less than the number of LEDs lit by the common cathode driving group 120 at the same time, the first bypass circuit 131 is controlled to be in the conducting state and the second bypass circuit 132 is controlled to be in the off state. At this time, the difference in current will flow into the common cathode driving group 120 through the first bypass circuit 131 to ensure that a normal current loop can be formed so that the current through the common anode driving group 110 and the common cathode driving group 120 is consistent.

[0109] When the number of LEDs lit by the common anode drive group 110 is greater than the number of LEDs lit by the common cathode drive group 120 at the same time, the first bypass circuit 131 is turned off and the second bypass circuit 132 is turned on. At this time, the remaining current of the common anode drive group 110 will flow to ground through the second bypass circuit 132 to bypass the excess current.

[0110] Based on this, by using the first bypass circuit 131 and the second bypass circuit 132, even when the number of LEDs lit by the common anode drive group 110 and the number of LEDs lit by the common cathode drive group 120 are inconsistent at the same time, the current distribution of the common anode drive group 110 and the common cathode drive group 120 can be ensured, thus preventing the drive circuit 100 from failing to form a normal current loop and improving the reliability of the display module.

[0111] In one embodiment, the display system includes a main control circuit, a power supply, and at least one display module in any of the above embodiments;

[0112] The main control circuit and power supply are connected to the display module.

[0113] The main control circuit includes a control chip; the control chip may be, but is not limited to, a microcontroller unit; the main control circuit is used to send corresponding control commands to the display module to control the display module to perform corresponding actions. These control commands may include, but are not limited to, scanning signals and preset display data.

[0114] The power supply is used to provide operating voltage to the display module.

[0115] For example, see Figure 8 Assume the display system includes four display modules, meaning the display system includes four driving circuits 100, with common-cathode and common-anode driving groups connected in series within each driving circuit 100; from Figure 8 It can be seen that the four driving circuits 100 form a 4×1 matrix. Based on the display module described in any of the above embodiments, assuming that each common anode driving group in each driving circuit 100 has 8 first driving terminals and each common cathode driving group has 8 second driving terminals, and assuming that the display module includes 8 scanning signal lines, it can be determined that the display system can be used to drive an LED array of 32 (columns)×16 (rows)-8 (scans) specifications.

[0116] In this embodiment, the display system can effectively balance the voltage distribution between each LED array in the display module and the driving circuit 100, effectively avoiding safety hazards such as overheating caused by excessive voltage differences, and effectively improving the safety of the display system.

[0117] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0118] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0119] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0120] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0121] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0122] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0123] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0124] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A driving circuit, characterized in that, The driving circuit includes a common anode driving group and a common cathode driving group; the common anode driving group and the common cathode driving group are connected in series; the common anode driving group has M first driving terminals; the common cathode driving group has M second driving terminals; where M is a natural number greater than 0. The first driving terminal is used to connect to the cathode of all LEDs in the corresponding column of the first LED array, and to perform display control on the LEDs in the corresponding column of the first LED array; The second driving terminal is used to connect to the anode of all LEDs in the corresponding column of the second LED array, and to perform display control on the LEDs in the corresponding column of the second LED array.

2. The driving circuit according to claim 1, characterized in that, The common anode drive group includes M first constant current sources; the common cathode drive group includes M second constant current sources; The first ends of the M first constant current sources are used to connect to the cathodes of all LEDs in the corresponding column of the first LED array; the second ends of the M first constant current sources are connected in parallel to each other to the first connection point. The first ends of the M second constant current sources are connected in parallel to each other to the second connection point; the second ends of the M second constant current sources are used to connect to the anodes of all LEDs in the corresponding column of the second LED array. The first connection point and the second connection point are connected in series.

3. The driving circuit according to claim 1, characterized in that, The driving circuit also includes a current compensation circuit; The first terminal of the current compensation circuit is connected to the power supply, the second terminal of the current compensation circuit is connected to the connection point of the common anode drive group and the common cathode drive group, and the third terminal of the current compensation circuit is grounded; the current compensation circuit is used to perform current compensation on the drive circuit.

4. The driving circuit according to claim 3, characterized in that, The current compensation circuit includes a first bypass circuit and a second bypass circuit; The first terminal of the first bypass circuit is used to connect to the power supply, and the second terminal of the first bypass circuit is connected to the connection point of the common anode drive group and the common cathode drive group. The first terminal of the second bypass circuit is connected to the connection point of the common anode drive group and the common cathode drive group, and the second terminal of the second bypass circuit is grounded.

5. The driving circuit according to claim 4, characterized in that, The first bypass circuit includes a first switch; the second bypass circuit includes a second switch. The first switch is used to turn the first bypass circuit on or off; The second switch is used to turn the second bypass circuit on or off.

6. A display module, characterized in that, The display module includes a first LED array, a second LED array, and a driving circuit according to any one of claims 1 to 5; the driving circuit includes a common anode driving group and a common cathode driving group; the common anode driving group has M first driving terminals; the common cathode driving group has M second driving terminals; the first LED array includes N×M LEDs; the second LED array includes N×M LEDs; wherein N and M are both natural numbers greater than 0; The cathodes of the N LEDs corresponding to the m-th column of the first LED array are connected to the m-th first driving terminal of the common anode driving group; where 0 < m ≤ M, and m is a natural number; The anodes of the N LEDs corresponding to the m-th column of the second LED array are connected to the m-th second driving terminal of the common cathode driving group.

7. The display module according to claim 6, characterized in that, The LED is a red LED.

8. The display module according to claim 6, characterized in that, The display module also includes N first switching circuits, N second switching circuits, and N scan signal lines; The first terminal of the nth first switch circuit is connected to the anode of the M LEDs corresponding to the nth row of the first LED array; the second terminal of the nth first switch circuit is connected to the power supply; the third terminal of the nth first switch circuit is connected to the nth scan signal line; the first switch circuit is used to start or stop providing power to the M LEDs corresponding to the nth row of the first LED array according to the scan signal transmitted by the nth scan signal line; where 0 < n ≤ N, and n is a natural number; The first terminal of the nth second switch circuit is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array; the second terminal of the nth second switch circuit is connected to the nth scan signal line; the third terminal of the nth second switch circuit is grounded; the second switch circuit is used to start or stop providing power to the M LEDs corresponding to the nth row of the second LED array according to the scan signal transmitted by the nth scan signal line.

9. The display module according to claim 8, characterized in that, The first switching circuit includes a first switching transistor; The drain of the nth first switch is connected to the anode of the M LEDs corresponding to the nth row of the first LED array; the source of the nth first switch is connected to the power supply; and the gate of the nth first switch is connected to the nth scan signal line.

10. The display module according to claim 9, characterized in that, The second switching circuit includes a second switching transistor and logic circuitry; The input terminal of the nth logic circuit is connected to the nth scan signal line, and the output terminal of the nth logic circuit is connected to the gate of the nth second switch. The source of the nth second switch is connected to the cathode of the M LEDs corresponding to the nth row of the second LED array; the drain of the nth second switch is grounded.

11. The display module according to claim 10, characterized in that, The first switching transistor is a PMOS transistor. The second switch is an NMOS transistor.

12. The display module according to claim 10, characterized in that, The logic circuit includes an inverter.

13. A display system, characterized in that, The display system includes a main control circuit, a power supply, and at least one display module as described in any one of claims 6 to 12; The main control circuit and the power supply are connected to the display module.

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