CN105304047B - Protect circuit and the liquid crystal display with the protection circuit - Google Patents
Protect circuit and the liquid crystal display with the protection circuit Download PDFInfo
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- CN105304047B CN105304047B CN201510799376.8A CN201510799376A CN105304047B CN 105304047 B CN105304047 B CN 105304047B CN 201510799376 A CN201510799376 A CN 201510799376A CN 105304047 B CN105304047 B CN 105304047B
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- power management
- management chip
- protection circuit
- switch
- load
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Abstract
One aspect of the present invention provides a kind of protection circuit; it is used for liquid crystal display; the liquid crystal display includes power management chip and the load being connected with the power management chip; the power management chip provides driving voltage to the load; the protection circuit is connected between the power management chip and the load, which includes control module, which detects the output current of the power management chip; and when it is more than preset current threshold, close the power management chip.The present invention also provides a kind of liquid crystal displays with above-mentioned protection circuit.Protection circuit of the present invention and liquid crystal display with the protection circuit can be effectively prevented from liquid crystal display damage when electric current is excessive with excess current protective function.
Description
Technical field
The present invention relates to field of liquid crystal display, more particularly, to a kind of liquid crystal protected circuit and there is the protection circuit
Show device.
Background technology
The protection circuit of the part driving voltage VGH of the power management chip of existing liquid crystal display only has under-voltage guarantor
Protective function without excess current protective function, therefore, works as circuit abnormal, when there is the impact of instantaneous large-current such as short circuit,
The corresponding module of the power management chip may be caused to burn, power unit disabler, so as to blank screen phenomenon occur so that aobvious
Show panel breakage and can not restore.
Invention content
The present invention provides a kind of liquid crystal display protected circuit and have the protection circuit, with overcurrent protection work(
Can, liquid crystal display can be effectively prevented from and damaged due to electric current is excessive.
One aspect of the present invention provides a kind of protection circuit, is used for liquid crystal display, which includes power supply
Managing chip and the load being connected with the power management chip, the power management chip provide driving voltage to the load, the guarantor
Protection circuit is connected between the power management chip and the load, which includes control module, control module detecting
The output current of the power management chip, and when it is more than preset current threshold, close the power management chip.
Wherein, which includes first switch and second switch, when the electric current of the power management chip is more than default
Current threshold when, the first switch and the second switch conducting, which is closed.
Wherein, the first switch be NPN type triode, the second switch be PNP type triode, the current collection of the first switch
Pole is connected with the power management chip, controls its open and close, emitter ground connection, and base stage is grounded through first resistor；This second
The emitter of switch is connected with the power management chip, detects its output current, collector through second resistance be connected to this first
The base stage of switch, base stage are connected to the load.
Wherein, which further includes the resistive module being connected with the control module, and the resistive module is by adjusting electricity
The size of resistance value sets the size of the current threshold.
Wherein, which includes main resistor and several resistance units, and each resistance unit includes basic resistance and control
System switch, by controlling each control switch can be in parallel with the main resistor by corresponding basic resistance, to adjust the resistive mode
The size of the resistance value of block.
Wherein, control switch is N-type metal-oxide-semiconductor, and the drain electrode of the control switch of each resistance unit is connected to source electrode
The both ends of the basic resistance, it is in parallel with main resistor after the series connection of each two resistance unit.
Wherein, the leakage of the source electrode and another control switch of one of control switch of the resistance unit of each two series connection
Extremely it is connected, draining for one of control switch is respectively connected to the both ends of main resistor with the source electrode of another control switch.
Another aspect of the present invention provides a kind of liquid crystal display, including power management chip and the power management core
The load and the protection circuit being connected between the power management chip and the load that piece is connected, the power management chip provide drive
To the load, which is connected between the power management chip and the load dynamic voltage, which includes control
Module, which detects the output current of the power management chip, and when it is more than preset current threshold, closes
The power management chip.
Wherein, which includes output pin and enabled pin, the protection circuit and the output pin and should
Enabled pin is connected, and passes through the output pin and detect the power management chip output current, and pin is enabled by the electricity by this
Source control chip is closed.
Wherein, which further includes micro-control unit, which is connected with the protection circuit, can set
The size of the current threshold of the protection circuit.
Compared to the prior art, the protection circuit of the liquid crystal display described in the embodiment of the present invention in circuit abnormal,
When there is instantaneous large-current and the current threshold more than protection circuit presets such as short circuit, that is, power management chip is turned off, from
And it is effectively prevented from liquid crystal display and is damaged due to electric current is excessive.In addition, the size of current threshold can be adjusted in MCU,
Therefore, which has more flexibility and practicability.
Description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, to embodiment or will show below
There is attached drawing needed in technology description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention, for those of ordinary skill in the art, without creative efforts, can be with
Other attached drawings are obtained according to these attached drawings.
Fig. 1 is the partial circuit diagram of the liquid crystal display with protection circuit of the embodiment of the present invention.
Specific embodiment
Below in conjunction with the attached drawing in the embodiment of the present invention, the technical solution in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art are obtained every other without making creative work
Embodiment shall fall within the protection scope of the present invention.
In addition, the explanation of following embodiment is with reference to additional diagram, the spy implemented the present invention to be illustrated to can be used to
Determine embodiment.Direction term mentioned in the present invention, for example, " on ", " under ", "front", "rear", "left", "right", " interior ",
" outer ", " side " etc. are only the directions with reference to annexed drawings, and therefore, the direction term used is to more preferably, more clearly say
It is bright and understand the present invention rather than instruction or imply signified device or element must have specific orientation, with specific side
Position construction and operation, therefore be not considered as limiting the invention.
In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " installation ", " phase
Even ", " connection " should be interpreted broadly, for example, it may be being fixedly connected or detachably connected or integrally connect
It connects；It can be mechanical connection；It can be directly connected, can also be indirectly connected by intermediary, can be in two elements
The connection in portion.For the ordinary skill in the art, the tool of above-mentioned term in the present invention can be understood with concrete condition
Body meaning.
In addition, in the description of the present invention, unless otherwise indicated, " multiple " are meant that two or more.If this
Occur the term of " process " in specification, refer not only to independent process, when can not clearly be distinguished with other process, as long as
It can realize that the effect desired by the process is then also included in this term.In addition, the numerical value model represented in this specification with "~" 0
Enclose the range for referring to that "~" front and rear numerical value recorded is included as minimum value and maximum value.In the accompanying drawings, structure
Similar or identical unit is indicated by the same numeral.
Referring to Fig. 1, Fig. 1 is the partial circuit diagram of the liquid crystal display with protection circuit of the present invention.Such as Fig. 1 institutes
Show, which includes power management chip 10, load 30, protection circuit 50 and micro-control unit
(Microcontroller Unit, MCU) 70.The power management chip 10 is connected to the load 30 through the protection circuit 50, should
Micro-control unit 70 is connected with the protection circuit 50.The power management chip 10 provides driving voltage to the load 30, the protection
Circuit 50 detects the output current of power management chip 10, and when it is more than preset current threshold, closes the power supply pipe
Chip 10 is managed, to carry out overcurrent protection.The MCU 70 is used for the size to the preset current threshold of the protection circuit 50
It is configured, to meet different protection demands.
The power management chip 10 includes output pin VGH and enabled pin En.Output pin VGH is through the protection circuit
50 are connected with the load 30, for outputting drive voltage.The Enable Pin pin En is connected with the protection circuit 50, for exporting
When the electric current of pin VGH is more than preset current threshold, the power management chip 10 is closed, to provide over current protection to it
Shield.In this preferred embodiment, when which works normally, which is high level, when this is enabled
When pin En is set as low level, which closes, and restarts the power management chip 10, the enabled pin
En reverts to high level.
The protection circuit 50 includes control module 51 and coupled resistive module 53.The control module 51 includes first
T1 and second switch T2 is switched, in this preferred embodiment, first switch T1 is NPN type triode, and second switch T2 is
PNP type triode.The collector C of first switch T1 is connected with the enabled pin En, controls opening for the power management chip 10
It opens and closes, emitter E ground connection, base stage B is grounded through first resistor R1.The emitter E of second switch T2 and the output pin
VGH is connected, and detects its output current, and collector C is connected to the base stage B of first switch T1, base stage B connections through second resistance R2
To load 30.The original state of first switch T1 and second switch T2 are cut-off state, when the electric current of output terminal VGH is more than
During preset current threshold, first switch T1 and second switch T2 conductings so that the enabled of power management chip 10 is drawn
Foot En is converted to low level by high level, so as to which power management chip 10 be closed, plays the role of overcurrent protection.
The resistive module 53 includes main resistor Rm and several resistance units 531.Main resistor R0 is connected in parallel to second switch T2
Emitter E and base stage B between.In this preferred embodiment, which includes 6 resistance units 531, Mei Yi electricity
It hinders unit 531 and includes basic resistance R0 and control switch Q, in this preferred embodiment, control switch Q is N-type metal-oxide-semiconductor,
Drain D is connected to the both ends of basic resistance R0 with source S, and grid G is connected with MCU 70.Each two resistance unit 531 is connected
It is in parallel with main resistor R0 afterwards, specifically, the source S of one of control switch Q of the resistance unit 531 of each two series connection with it is another
The drain D of one control switch Q is connected, and the drain D and the source S of another control switch Q of one of control switch Q are distinguished
It is connected to the both ends of main resistor Rm.
The protection circuit 50 further includes capacitance C1, and capacitance C1 is connected in parallel to resistive module 53, to filtering noise information.
The MCU 70 includes several with 531 corresponding controlling switch of resistance unit, in this preferred embodiment, shares 6
Controlling switch CK1 to CK6, the grid G for switching Q with the control of 6 resistance units 531 respectively are connected, and MCU 70, which passes through, exports height
Low level adjusts its resistance to control conducting and the cut-off state of switch Q by corresponding basic resistance R0 access resistive modules 53
Value, so as to set the threshold value of corresponding electric current.When the outputs of MCU 70 are 111111, all control switch Q places are led example 70
Logical state, the resistance value Rs of resistive module 53 are the resistance value of main resistor Rm, when the outputs of MCU 70 are 011111, resistive module
53 resistance value Rs is the resistance value after basis resistance R0 is in parallel with main resistor Rm.Obviously, the control of resistance unit 531 and MCU 70
The specific number of pin processed can be increased and decreased according to practical demand, correspondingly, the connection side of resistance unit 531 and main resistor Rm
Formula can be changed according to practical circuit design.
When liquid crystal display 100 of the present invention works, the enabled pin En of the power management chip 10 is high level,
Output pin VGH provides driving voltage to load 30.Work as circuit abnormal, be more than protection electricity as instantaneous large-current occurs in short circuit
During 50 preset current threshold of road, first switch T1 is connected with second switch T2, which is converted by high level
For low level, so as to which power management chip 10 be closed, to carry out overcurrent protection, meanwhile, which can also pass through control
Basic resistance R0 is accessed resistive module 53 to set the current threshold by the conducting of control switch Q with cut-off state.
In conclusion the protection circuit 10 of the liquid crystal display 100 described in the embodiment of the present invention is in circuit abnormal, such as
When short circuit instantaneous large-current occurs and is more than protection 50 preset current threshold of circuit, that is, power management chip 10 is turned off,
It is damaged due to electric current is excessive so as to be effectively prevented from liquid crystal display 100.In addition, MCU 70 can to the size of current threshold into
Row is adjusted, and therefore, which has more flexibility and practicability.
In the description of this specification, reference term " one embodiment ", " example ", " is specifically shown " some embodiments "
The description of example " or " some examples " etc. means to combine the embodiment or example particular features, structures, materials, or characteristics described
It is contained at least one embodiment of the present invention or example.In the present specification, schematic expression of the above terms differ
Surely identical embodiment or example are referred to.Moreover, the particular features, structures, materials, or characteristics of description can be any one
It is combined in an appropriate manner in a or multiple embodiments or example.
Above disclosed is only a kind of preferred embodiment of the present invention, cannot limit the power of the present invention with this certainly
Sharp range one of ordinary skill in the art will appreciate that realizing all or part of flow of above-described embodiment, and is weighed according to the present invention
Profit requires made equivalent variations, still falls within and invents covered range.
Claims (9)
1. a kind of protection circuit, is used for liquid crystal display, the liquid crystal display include power management chip, micro-control unit and
The load being connected with the power management chip, the power management chip provide driving voltage to the load, the power management chip
Including output pin and enabled pin, which is characterized in that the protection circuit is connected to the output pin of the power management chip
And between the load, the power management chip by the output pin outputting drive voltage to the load, the enabled pin with
The protection circuit is connected, which includes control module and resistive module, which detects the power management chip
The output pin output current, and its be more than preset current threshold when, which enables pin by this
The power management chip is closed, the size of the preset current threshold is needed via difference of the micro-control unit according to the load
It asks and the size of the resistance value of the resistive module is adjusted to be configured.
2. protection circuit as described in claim 1, which is characterized in that the control module includes first switch and second switch,
When the electric current of the power management chip is more than preset current threshold, the first switch and second switch conducting will
The power management chip is closed.
3. as claimed in claim 2 protection circuit, which is characterized in that the first switch be NPN type triode, the second switch
For PNP type triode, the collector of the first switch is connected with the power management chip, controls its open and close, emitter
Ground connection, base stage are grounded through first resistor；The emitter of the second switch is connected with the power management chip, detects its output electricity
Stream, collector are connected to the base stage of the first switch through second resistance, and base stage is connected to the load.
4. protection circuit as claimed in claim 3, which is characterized in that the resistive module includes main resistor and several resistance lists
Member, each resistance unit include basic resistance and control switch, by controlling each control switch can be by corresponding basis electricity
Resistance is in parallel with the main resistor, to adjust the size of the resistance value of the resistive module.
5. protection circuit as claimed in claim 4, which is characterized in that the control is switched as N-type metal-oxide-semiconductor, each resistance list
The drain electrode of the control switch of member is connected to the both ends of the basic resistance with source electrode, after the series connection of each two resistance unit with main resistor simultaneously
Connection.
6. protection circuit as claimed in claim 5, which is characterized in that one of control of the resistance unit of each two series connection
The source electrode of switch is connected with the drain electrode of another control switch, drain electrode and another control switch of one of control switch
Source electrode is respectively connected to the both ends of main resistor.
7. a kind of liquid crystal display, the load being connected including power management chip, with the power management chip and it is connected to this
Protection circuit between power management chip and the load, the power management chip provide driving voltage to the load, the protection
Circuit is connected between the power management chip and the load, which is characterized in that the protection circuit is to appoint in claim 1-5
Protection circuit described in meaning one.
8. liquid crystal display as claimed in claim 7, which is characterized in that the power management chip includes output pin and enables
Pin, the protection circuit are connected, and pass through the output pin and detect the power management core with the output pin and the enabled pin
Piece output current enables pin by this and closes the power management chip.
9. liquid crystal display as claimed in claim 7, which is characterized in that the liquid crystal display further includes micro-control unit, should
Micro-control unit is connected with the protection circuit, can set the size of the current threshold of the protection circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510799376.8A CN105304047B (en) | 2015-11-19 | 2015-11-19 | Protect circuit and the liquid crystal display with the protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510799376.8A CN105304047B (en) | 2015-11-19 | 2015-11-19 | Protect circuit and the liquid crystal display with the protection circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105304047A CN105304047A (en) | 2016-02-03 |
| CN105304047B true CN105304047B (en) | 2018-07-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510799376.8A Active CN105304047B (en) | 2015-11-19 | 2015-11-19 | Protect circuit and the liquid crystal display with the protection circuit |
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| CN (1) | CN105304047B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106707590A (en) * | 2017-02-27 | 2017-05-24 | 深圳市华星光电技术有限公司 | Display panel over-temperature protection system and display panel over-temperature protection method |
| CN109949742B (en) * | 2017-12-20 | 2021-04-27 | 上海和辉光电股份有限公司 | Display panel's drive circuit and display panel |
| CN110010099B (en) | 2019-04-29 | 2020-08-04 | 深圳市华星光电技术有限公司 | Voltage stabilizing circuit, control method and display device |
| CN110890052B (en) * | 2019-11-29 | 2021-02-02 | Tcl华星光电技术有限公司 | Driving circuit, driving method and display device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7492162B2 (en) * | 2002-07-22 | 2009-02-17 | Fujitsu Limited | Inverter system |
| CN101630489A (en) * | 2009-08-03 | 2010-01-20 | 深圳创维－Rgb电子有限公司 | Power supply circuit of liquid crystal display |
| CN101908395A (en) * | 2009-06-08 | 2010-12-08 | 武汉市创佳源电子有限公司 | General electronic potentiometer module network resistor assembly |
| CN103606884A (en) * | 2013-11-25 | 2014-02-26 | 深圳市华星光电技术有限公司 | Over-current protection circuit, LED backlight drive circuit and liquid crystal display |
| JP5492728B2 (en) * | 2010-09-28 | 2014-05-14 | 株式会社ジャパンディスプレイ | Display device |
| CN203607179U (en) * | 2013-12-04 | 2014-05-21 | 广东美的制冷设备有限公司 | Resistor box |
| CN204559102U (en) * | 2015-03-25 | 2015-08-12 | 长沙市博巨兴电子科技有限公司 | A kind of power output short-circuit protection circuit |
-
2015
- 2015-11-19 CN CN201510799376.8A patent/CN105304047B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7492162B2 (en) * | 2002-07-22 | 2009-02-17 | Fujitsu Limited | Inverter system |
| CN101908395A (en) * | 2009-06-08 | 2010-12-08 | 武汉市创佳源电子有限公司 | General electronic potentiometer module network resistor assembly |
| CN101630489A (en) * | 2009-08-03 | 2010-01-20 | 深圳创维－Rgb电子有限公司 | Power supply circuit of liquid crystal display |
| JP5492728B2 (en) * | 2010-09-28 | 2014-05-14 | 株式会社ジャパンディスプレイ | Display device |
| CN103606884A (en) * | 2013-11-25 | 2014-02-26 | 深圳市华星光电技术有限公司 | Over-current protection circuit, LED backlight drive circuit and liquid crystal display |
| CN203607179U (en) * | 2013-12-04 | 2014-05-21 | 广东美的制冷设备有限公司 | Resistor box |
| CN204559102U (en) * | 2015-03-25 | 2015-08-12 | 长沙市博巨兴电子科技有限公司 | A kind of power output short-circuit protection circuit |
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| CN105304047A (en) | 2016-02-03 |
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