Undervoltage protection circuit and display device

Abstract

The utility model discloses an under-voltage protection circuit and display equipment, and relates to the technical field of display, the under-voltage protection circuit is connected between a power supply voltage end and an LED module, and the under-voltage protection circuit comprises an input module, a logic module and an output module; a first switch unit is arranged in the input module, and the first switch unit is used for outputting a signal value to be judged according to an accessed input signal value; the logic module is used for performing logic operation according to the accessed signal value to be judged and generating an output signal value based on the logic operation; according to the undervoltage protection circuit, various signal values can be transmitted on one signal line, and reduction of effective transmission efficiency caused by adding extra coding bits is avoided through logical operation of the logic module, so that the response speed of the undervoltage protection circuit is improved, the undervoltage protection speed of display equipment can be improved to a certain extent, and the service life of the display equipment is prolonged. And the phenomenon of equipment damage caused by undervoltage protection operation delay is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to an under-voltage protection circuit and a display device. BACKGROUND

[0002] The under-voltage protection circuit is a key component to ensure the stable operation of the display device and prevent hardware damage. It is usually used to monitor the power supply voltage and take protective measures quickly when the voltage drops below the safe working level. However, the conventional under-voltage protection circuit has some limitations in design and implementation, especially in transmission rate and response time.

[0003] The conventional under-voltage protection circuit usually needs to configure two data lines, in addition, in order to improve the reliability and accuracy of data transmission, additional encoding bits are needed to encode and decode the signal, and the way limits the data transmission rate to a certain extent, which causes the under-voltage protection circuit to fail to respond to voltage changes in time and achieve fast under-voltage protection of the display device. CONTENT OF THE UTILITY MODEL

[0004] The main purpose of the present application is to provide an under-voltage protection circuit and a display device, which aims to solve the technical problem that the conventional under-voltage protection circuit has limitations and causes the under-voltage protection to be unable to be quickly implemented.

[0005] To achieve the above-mentioned purpose, the present application provides an under-voltage protection circuit, which is connected between a power supply voltage terminal and an LED module. The under-voltage protection circuit comprises an input module, a logic module and an output module.

[0006] The first switching unit in the input module is used to output a signal value to be judged according to the input signal value connected;

[0007] The logic module is used to perform logic operation according to the input signal value to be judged, and generate an output signal value based on the logic operation;

[0008] The second switching unit in the output module is used to perform conduction judgment according to the input output signal value.

[0009] In an embodiment, the input module comprises a first signal connection end connected with a first signal output end of a controller, and the first switching unit comprises a first switching subunit connected with the first signal connection end;

[0010] The first switching subunit comprises a first switching tube and a second switching tube.

[0011] The control end of the first switch tube and the control end of the second switch tube are connected to the first signal access end, the input end of the first switch tube and the input end of the second switch tube are respectively connected to the power voltage end, the input end of the first switch tube is further connected to the logic module, and the output end of the second switch tube is connected to the logic module.

[0012] In an embodiment, the input module further comprises a second signal access end connected to the second signal output end of the controller, and the first switch unit further comprises a second switch subunit connected to the second signal access end.

[0013] The second switch subunit comprises a third switch tube and a fourth switch tube.

[0014] The control end of the third switch tube and the control end of the fourth switch tube are connected to the second signal access end, the input end of the third switch tube and the input end of the fourth switch tube are respectively connected to the power voltage end, the input end of the third switch tube is further connected to the logic module, and the output end of the fourth switch tube is connected to the logic module.

[0015] In an embodiment, the logic module comprises a first judgment module connected to the first switch subunit, and the first judgment module comprises a first NOT gate, a first NAND gate and a fifth switch tube.

[0016] The first input end of the first NAND gate is connected to the input end of the first switch tube, the second input end of the first NAND gate is connected to the output end of the second switch tube through the first NOT gate, the output end of the first NAND gate is connected to the control end of the fifth switch tube, and the input end of the fifth switch tube is connected to the power voltage end.

[0017] In an embodiment, the logic module comprises a second judgment module connected to the second switch subunit, and the second judgment module comprises a second NOT gate, a second NAND gate and a sixth switch tube.

[0018] The first input end of the second NAND gate is connected to the input end of the third switch tube, the second input end of the second NAND gate is connected to the output end of the fourth switch tube through the second NOT gate, the output end of the second NAND gate is connected to the control end of the sixth switch tube, and the input end of the sixth switch tube is connected to the power voltage end.

[0019] In an embodiment, the logic module further comprises a first NOR gate and a third NOT gate.

[0020] The first input end of the first NOR gate is connected to the first signal access end, and the second input end of the first NOR gate is connected to the second signal access end.

[0021] The output end of the fifth switch tube and the output end of the sixth switch tube are connected to the input end of the third NOT gate.

[0022] In an embodiment, the logic module further comprises a first output logic judging unit, and the first output logic judging unit comprises a third NAND gate;

[0023] The first input end of the third NAND gate is connected with the output end of the third NAND gate, and the second input end of the third NAND gate is connected with the output end of the first NOR gate.

[0024] In an embodiment, the logic module further comprises a second output logic judging unit, and the second output logic judging unit comprises a second NOR gate;

[0025] The first input end of the second NOR gate is connected with the output end of the first NOR gate, and the second input end of the second NOR gate is connected with the input end of the third NAND gate.

[0026] In an embodiment, the second switch unit comprises a third switch subunit and a fourth switch subunit, the third switch subunit comprises a seventh switch tube, and the fourth switch subunit comprises an eighth switch tube;

[0027] The control end of the seventh switch tube is connected with the output end of the third NAND gate, and the input end of the seventh switch tube is connected with the power supply voltage end;

[0028] The control end of the eighth switch tube is connected with the output end of the second NOR gate, the input end of the eighth switch tube is connected with the output end of the seventh switch tube and the LED module, and the output end of the eighth switch tube is connected with the ground end.

[0029] In addition, to achieve the above-mentioned purpose, the application further provides a display device comprising the under-voltage protection circuit as described above.

[0030] The one or more technical solutions provided in the application have at least the following technical effects:

[0031] An under-voltage protection circuit is provided, which is connected between a power supply voltage end and an LED module, and comprises an input module, a logic module and an output module. The input module is provided with a first switch unit, which is used to output a to-be-judged signal value according to an input signal value. The logic module is used to perform logic operation according to the to-be-judged signal value, and generate an output signal value based on the logic operation. The output module is provided with a second switch unit, which is used to perform conduction judgment according to the output signal value.

[0032] That is, the application builds the under-voltage protection circuit of the input module, the logic module and the output module, transmits multiple signal values on one signal line, avoids the reduction of effective transmission efficiency caused by the increase of additional coding bits through the logic operation of the logic module, thereby improving the response speed of the under-voltage protection circuit, and to a certain extent, improving the under-voltage protection speed of the display device and avoiding the damage of the device caused by the delay of the under-voltage protection operation. Attached Figure Description

[0033] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 A schematic diagram of the module for the undervoltage protection circuit of this application;

[0036] Figure 2 This is a schematic diagram of a circuit structure for the undervoltage protection circuit of this application.

[0037] Explanation of icon numbers:

[0038] VCC, power supply voltage terminal;

[0039] 10. Input module; A. First signal input terminal; B. Second signal input terminal; Q1. First switch transistor; Q2. Second switch transistor; Q3. Third switch transistor; Q4. Fourth switch transistor; R1. First resistor; R2. Second resistor; R3. Third resistor; R4. Fourth resistor;

[0040] 20. Logic Module; F1, First NOT Gate; YF1, First NAND Gate; F2, Second NOT Gate; YF2, Second NAND Gate; Q5, Fifth Switch; Q6, Sixth Switch; HF1, First NOR Gate; F3, Third NOT Gate; YF3, Third NAND Gate; HF2, Second NOR Gate; R5, Fifth Resistor;

[0041] 30. Output module; Q7, seventh switch; Q8, eighth switch; R6, sixth resistor.

[0042] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0043] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0044] It should be noted that if the application embodiments involve directionality indication (such as up, down, left, right, front, back, …), the directionality indication is only used to explain the relative position relationship, motion condition, etc. between the components in a certain posture, and if the certain posture changes, the directionality indication will also change accordingly.

[0045] In addition, if the application embodiments involve "first", "second" and the like, the "first", "second" and the like are only for description purposes, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first" and "second" can be explicitly or implicitly included at least one of the features. In addition, "and / or" or "and / or" appears throughout the text, which means that the three parallel schemes include "A and / or B", which includes A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection claimed by the present application.

[0046] Based on this, the application embodiment provides an under-voltage protection circuit, referring to Figure 1 , Figure 1 The module schematic diagram of the under-voltage protection circuit of the application.

[0047] In this embodiment, the under-voltage protection circuit is connected between the power supply voltage terminal VCC and the LED module, and the under-voltage protection circuit includes an input module 10, a logic module 20 and an output module 30.

[0048] The first switching unit is arranged in the input module 10, and the first switching unit is used to output a to-be-judged signal value according to the input signal value connected; the logic module 20 is used to perform logic operation according to the to-be-judged signal value connected, and generate an output signal value based on the logic operation; the second switching unit is arranged in the output module 30, and the second switching unit is used to perform conduction judgment according to the output signal value connected.

[0049] The input end of the input module 10 is connected with a controller, the controller compares the driving voltage value on the current LED module with the safe driving voltage value according to the driving voltage value on the current LED module connected, so as to judge whether the driving voltage value on the current LED module is lower than the safe driving voltage value, and output the corresponding input signal value according to the corresponding judgment result, so that the rapid under-voltage response of the LED module is realized through the under-voltage protection circuit.

[0050] And the input module 10 generates the to-be-judged signal value according to the input signal value input by the controller, and then inputs the generated to-be-judged signal value into the logic module 20 for logical operation, and generates an output signal value, so that the output module 30 can perform the corresponding undervoltage protection operation according to the output signal value. The specific operation of the undervoltage protection based on the undervoltage protection voltage proposed in the embodiment can be referred to Figure 2 .

[0051] In a possible implementation, the specific structure of the undervoltage protection circuit proposed in the application can be referred to Figure 2 .

[0052] The input module 10 includes a first signal access end A connected to the first signal output end of the controller, and the first switching unit includes a first switching subunit connected to the first signal access end A.

[0053] The first switching subunit includes a first switch Q1 and a second switch Q2. The control end of the first switch Q1 and the control end of the second switch Q2 are connected to the first signal access end A. The input end of the first switch Q1 and the input end of the second switch Q2 are respectively connected to the power supply voltage end VCC. The input end of the first switch Q1 is also connected to the logic module 20. The output end of the second switch Q2 is connected to the logic module 20.

[0054] According to Figure 2 It can be known that the first signal access end A connected to the first signal output end of the controller is used for switching control of the first switch Q1 and the second switch Q2. The controller generates different input signal values according to the input signal value representing the current driving voltage value on the LED module, and controls the switching state of the first switch Q1 and the second switch Q2, so as to generate corresponding to-be-judged logic values to the logic module 20.

[0055] The input module 10 further includes a second signal access end B connected to the second signal output end of the controller, and the first switching unit further includes a second switching subunit connected to the second signal access end B.

[0056] The second switching subunit includes a third switch Q3 and a fourth switch Q4. The control end of the third switch Q3 and the control end of the fourth switch Q4 are connected to the second signal access end B. The input end of the third switch Q3 and the input end of the fourth switch Q4 are respectively connected to the power supply voltage end VCC. The input end of the third switch Q3 is also connected to the logic module 20. The output end of the fourth switch Q4 is connected to the logic module 20.

[0057] In addition, the second signal access end B connected with the second signal output end of the controller is respectively used for switching control of the third switch tube Q3 and the fourth switch tube Q4, and the controller generates different input signal values according to the accessed driving voltage value on the current LED module to control the switching state of the third switch tube Q3 and the fourth switch tube Q4, so as to generate a corresponding to-be-judged logic value to the logic module 20.

[0058] Further, the logic module 20 includes a first judging module connected with the first switching subunit, the first judging module including a first NOT gate F1, a first NAND gate YF1 and a fifth switch tube Q5; the first input end of the first NAND gate YF1 is connected with the input end of the first switch tube Q1, the second input end of the first NAND gate YF1 is connected with the output end of the second switch tube Q2 via the first NOT gate F1, the output end of the first NAND gate YF1 is connected with the control end of the fifth switch tube Q5, and the input end of the fifth switch tube Q5 is connected to the power voltage end VCC.

[0059] The logic module 20 includes a second judging module connected with the second switching subunit, the second judging module including a second NOT gate F2, a second NAND gate YF2 and a sixth switch tube Q6; the first input end of the second NAND gate YF2 is connected with the input end of the third switch tube Q3, the second input end of the second NAND gate YF2 is connected with the output end of the fourth switch tube Q4 via the second NOT gate F2, the output end of the second NAND gate YF2 is connected with the control end of the sixth switch tube Q6, and the input end of the sixth switch tube Q6 is connected to the power voltage end VCC.

[0060] In the logic module 20, the first judging module connected with the first switching subunit and the first judging module connected with the second switching subunit are respectively provided.

[0061] According to Figure 2 It can be known that, in the first judging module and the second judging module, the NAND gate and the NOT gate are provided, so as to correspondingly convert the to-be-judged logic value output from the first switching subunit and the second switching subunit.

[0062] The logic module 20 further includes a first NOR gate HF1 and a third NOT gate F3.

[0063] The first input end of the first NOR gate HF1 is connected with the first signal access end A, the second input end of the first NOR gate HF1 is connected with the second signal access end B, and the output end of the fifth switch tube Q5 and the output end of the sixth switch tube Q6 are commonly connected to the input end of the third NOT gate F3.

[0064] The logic module 20 further comprises a first output logic judging unit, the first output logic judging unit comprising a third NAND gate YF3; a first input end of the third NAND gate YF3 is connected with an output end of the third NAND gate F3, and a second input end of the third NAND gate YF3 is connected with an output end of the first NOR gate HF1.

[0065] The logic module 20 further comprises a second output logic judging unit, the second output logic judging unit comprising a second NOR gate HF2; a first input end of the second NOR gate HF2 is connected with an output end of the first NOR gate HF1, and a second input end of the second NOR gate HF2 is connected with an input end of the third NAND gate F3.

[0066] According to Figure 2 It can be known that, in the embodiment, the logic module 20 further comprises the first NOR gate HF1, the third NAND gate F3, the first output logic judging unit and the second output logic judging unit in addition to the first judging module and the second judging module, corresponding logic judging gates are arranged in the logic module 20, so as to judge and convert the input logic value and output the output value to the output module 30.

[0067] Further, the second switch unit comprises a third switch subunit and a fourth switch subunit, the third switch subunit comprising a seventh switch tube Q7, and the fourth switch subunit comprising an eighth switch tube Q8; a control end of the seventh switch tube Q7 is connected with an output end of the third NAND gate YF3, and an input end of the seventh switch tube Q7 is connected with a power supply voltage end VCC; a control end of the eighth switch tube Q8 is connected with an output end of the second NOR gate HF2, an input end of the eighth switch tube Q8 is connected with an output end of the seventh switch tube Q7 to an LED module, and an output end of the eighth switch tube Q8 is connected with a ground end.

[0068] Specifically, based on Figure 2 The undersupply protection process that can be realized is shown as follows, which is explained in combination with Table 1.

[0069]

[0070]

[0071]

[0072]

[0073] ​​​​②When the controller compares the drive voltage value of the current LED module with the safe drive voltage value and finds that the current LED module needs to be protected from under-voltage, the first signal output port and the second signal output port can output the combination of "0, 1", "1, 0" or "1, 1". Taking the output signal value of "0, 1" as an example, according to the connection relationship, the first signal input end A transmits the input signal value of "0" to the first switch tube Q1 and the second switch tube Q2. At this time, the first switch tube Q1 is in the off state, and the second switch tube Q2 is in the on state. The first switch tube Q1 in the off state transmits the power supply voltage value on the power supply voltage end VCC to the first input end of the first NAND gate YF1. The second switch tube Q2 in the on state transmits the power supply voltage on the power supply voltage end VCC to the output end of the first NAND gate YF1, and outputs "0" to the second input end of the first NAND gate YF1. At this time, the first NAND gate YF1 outputs "1" to the control end of the fifth switch tube Q5, so that the fifth switch tube Q5 is in the off state.

[0074] The second signal input end B transmits the input signal value of "1" to the third switch tube Q3 and the fourth switch tube Q4. At this time, the third switch tube Q3 is in the on state, and the fourth switch tube Q4 is in the off state. The third switch tube Q3 in the on state flows the power supply voltage from the power supply voltage end VCC to the ground end, so that the logic value to be judged on the first input end of the second NAND gate YF2 is "0" at this time. The fourth switch tube Q4 in the off state has no power supply voltage on the output end, so that the logic value to be judged on the input end of the second NAND gate F2 is also "0" at this time. The second NAND gate F2 outputs "1" to the second input end of the second NAND gate YF2. At this time, the second NAND gate YF2 judges according to the logic value to be judged, and outputs "1" to the sixth switch tube Q6, so that the sixth switch tube Q6 is in the off state. The input end of the third NAND gate F3 is "0".

[0075] At this time, the third NAND gate F3 outputs "1" to the first input end of the third NAND gate YF3, and the first input end and the second input end of the first NOR gate HF1 input the input signal values of "0" and "1", so as to output "0".

[0076] At this time, the third NAND gate YF3 inputs "1" and "0" respectively, outputs the output signal value of "1", and the second NOR gate HF2 inputs "0" and "0" respectively at this time, outputs the output signal value of "1", so that the seventh switch tube Q7 is in the off state and does not input the power supply voltage on the power supply voltage end VCC. Because the eighth switch tube Q8 is in the on state at this time, the power supply voltage on the line of the LED module is discharged at this time, so as to inhibit the under-voltage risk of the LED module.

[0077] Table 1

[0078] A B LED module 0 0 1 0 1 0 1 0 0 1 1 0

[0079] It should be noted that, Figure 2 The first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 in the circuit serve as filters.

[0080] That is, this application establishes, for example Figure 2 The undervoltage protection circuit shown enables the transmission of two signal values ​​on a single signal line. Through the logic operation of the logic module 20, the reduction in effective transmission efficiency caused by adding extra encoding bits is avoided, thereby improving the response speed of the undervoltage protection circuit. This can improve the undervoltage protection speed of the display device to a certain extent and avoid equipment damage caused by undervoltage protection operation delay.

[0081] This application also provides a display device that includes the undervoltage protection circuit described above.

[0082] It is understood that, since the above-mentioned undervoltage protection circuit is used in the display device, the embodiments of the display device include all the technical solutions of all the embodiments of the above-mentioned undervoltage protection circuit, and the technical effects achieved are exactly the same, so they will not be repeated here.

[0083] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. An under-voltage protection circuit, characterized by, The under-voltage protection circuit is connected between a power voltage terminal and an LED module, and comprises an input module, a logic module and an output module. The first switching unit in the input module is used for outputting a signal value to be judged according to an input signal value accessed. The logic module is used for performing logic operation according to the signal value to be judged accessed, and generating an output signal value based on the logic operation. The second switching unit in the output module is used for conducting according to the output signal value accessed.

2. The under-voltage protection circuit of claim 1, wherein, The input module comprises a first signal access end connected with a first signal output end of a controller, and the first switching unit comprises a first switching subunit connected with the first signal access end. The first switching subunit comprises a first switch tube and a second switch tube. The control end of the first switch tube and the control end of the second switch tube are connected with the first signal access end, the input end of the first switch tube and the input end of the second switch tube are respectively connected with the power voltage terminal, the input end of the first switch tube is further connected to the logic module, and the output end of the second switch tube is connected to the logic module.

3. The under-voltage protection circuit of claim 2, wherein, The input module further comprises a second signal access end connected with a second signal output end of the controller, and the first switching unit further comprises a second switching subunit connected with the second signal access end. The second switching subunit comprises a third switch tube and a fourth switch tube. The control end of the third switch tube and the control end of the fourth switch tube are connected with the second signal access end, the input end of the third switch tube and the input end of the fourth switch tube are respectively connected with the power voltage terminal, the input end of the third switch tube is further connected to the logic module, and the output end of the fourth switch tube is connected to the logic module.

4. The under-voltage protection circuit of claim 3, wherein, The logic module comprises a first judging module connected with the first switching subunit, and the first judging module comprises a first non-gate, a first NAND gate and a fifth switch tube. The first input end of the first NAND gate is connected with the input end of the first switch tube, the second input end of the first NAND gate is connected with the output end of the second switch tube via the first non-gate, the output end of the first NAND gate is connected with the control end of the fifth switch tube, and the input end of the fifth switch tube is connected to the power voltage terminal.

5. The under-voltage protection circuit of claim 4, wherein, The logic module comprises a second judging module connected with the second switching subunit, and the second judging module comprises a second non-gate, a second NAND gate and a sixth switch tube. The first input end of the second NAND gate is connected with the input end of the third switch tube, the second input end of the second NAND gate is connected with the output end of the fourth switch tube via the second non-gate, the output end of the second NAND gate is connected with the control end of the sixth switch tube, and the input end of the sixth switch tube is connected to the power voltage terminal.

6. The under-voltage protection circuit of claim 5, wherein, The logic module further comprises a first NOR gate and a third non-gate. The first input end of the first NOR gate is connected with the first signal access end, and the second input end of the first NOR gate is connected with the second signal access end. An output terminal of the fifth switch tube and an output terminal of the sixth switch tube are connected to an input terminal of the third NOT gate.

7. The under-voltage protection circuit of claim 6, wherein, The logic module further comprises a first output logic judging unit, and the first output logic judging unit comprises a third NAND gate. A first input terminal of the third NAND gate is connected to an output terminal of the third NOT gate, and a second input terminal of the third NAND gate is connected to an output terminal of the first NOR gate.

8. The under-voltage protection circuit of claim 7, wherein, The logic module further comprises a second output logic judging unit, and the second output logic judging unit comprises a second NOR gate. A first input terminal of the second NOR gate is connected to an output terminal of the first NOR gate, and a second input terminal of the second NOR gate is connected to an input terminal of the third NOT gate.

9. The under-voltage protection circuit of claim 8, wherein, The second switch unit comprises a third switch sub-unit and a fourth switch sub-unit, the third switch sub-unit comprises a seventh switch tube, and the fourth switch sub-unit comprises an eighth switch tube. A control terminal of the seventh switch tube is connected to an output terminal of the third NAND gate, and an input terminal of the seventh switch tube is connected to the power supply voltage terminal. A control terminal of the eighth switch tube is connected to an output terminal of the second NOR gate, an input terminal of the eighth switch tube is connected to an output terminal of the seventh switch tube and the LED module, and an output terminal of the eighth switch tube is connected to a ground terminal.

10. A display device, characterized by comprising: The display device comprises the under-voltage protection circuit according to any one of claims 1 to 9.

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