CN206865123U - Protection circuit and electronic equipment - Google Patents

Abstract

The disclosure provides a kind of protection circuit and electronic equipment.Wherein, the protection circuit is used to protect driving chip, and driving chip is used to drive lamp bar to work.Protection circuit includes bleeder circuit and on-off circuit；The signal output part of the negative pole connection driving chip of lamp bar, the positive pole connection power supply of lamp bar；Signal output part is also connected with the input of bleeder circuit, the input of the output end connecting valve circuit of bleeder circuit, the Enable Pin of the output end connection driving chip of on-off circuit；Wherein, when the signal of signal output part is more than or equal to preset value, bleeder circuit works the branch pressure voltage trigger switch circuit that the signal of signal output part exported after partial pressure, and on-off circuit output causes the signal that driving chip is stopped to Enable Pin.The protection circuit and electronic equipment of the embodiment of the present disclosure, when short circuit occurs for lamp bar or other situations cause the signal of signal output part excessive, driving chip is stopped, avoid driving chip temperature too high and be damaged.

Description

Protection circuit and electronic equipment

Technical field

This disclosure relates to electronic technology field, more particularly to protection circuit and electronic equipment.

Background technology

Current electronic devices provide the back of the body using LED (Light Emitting Diode, light emitting diode) lamp bar Light.Flowed generally by power MOS (Metal Oxide Semiconductor) device is internally integrated in driving chip to do electric current, so as to control LED light bar to light.When Driving chip temperature can be caused to exceed the requirement of security regulations during lamp bar short circuit, and cause driving chip to damage.

It is the defencive function that is carried by driving chip mostly in related technical scheme to realize output short circuit protection, its Principle is that the high level of LED negative pole pins is counted to judge.But function during its short-circuit protection is not complete, such as multichannel There is short-circuit protection function during output, and without short-circuit protection function during single channel output.

Utility model content

The disclosure provides a kind of protection circuit and electronic equipment.

A kind of protection circuit is provided according to the first aspect of the embodiment of the present disclosure, for protecting driving chip, the driving Chip is used to drive lamp bar to work, and the protection circuit includes bleeder circuit and on-off circuit；The negative pole connection of the lamp bar is driven The signal output part of dynamic chip, the positive pole connection power supply of the lamp bar；The signal output part is also connected with the partial pressure electricity The input on road, the output end of the bleeder circuit connect the input of the on-off circuit, the output end of the on-off circuit Connect the Enable Pin of the driving chip；Wherein, when the signal of the signal output part is more than or equal to preset value, described point The branch pressure voltage that the signal of the signal output part exported after partial pressure is triggered the on-off circuit and worked by volt circuit, described On-off circuit output causes the signal that the driving chip is stopped to the Enable Pin.

Further, the bleeder circuit includes first resistor and second resistance；One end ground connection of the first resistor, separately One end is connected to the input of the on-off circuit；One end of the second resistance connects the signal output part, and the other end connects It is connected to the input of the on-off circuit.

Further, the on-off circuit includes triode；The input of the on-off circuit is the base of the triode Pole, the output end of the on-off circuit are the colelctor electrodes of the triode.

Further, the grounded emitter of the triode.

Further, the on-off circuit includes metal-oxide semiconductor (MOS) metal-oxide-semiconductor；The input of the on-off circuit is The grid of the metal-oxide-semiconductor, the output end of the on-off circuit are the drain electrodes of the metal-oxide-semiconductor.

Further, the source ground of the metal-oxide-semiconductor.

Further, mu balanced circuit is additionally provided between the input of the signal output part and the bleeder circuit, it is described The input of mu balanced circuit connects the signal output part, and the output end of the mu balanced circuit connects the input of the bleeder circuit End.

Further, the mu balanced circuit includes voltage-regulator diode；The anode of the voltage-regulator diode connects the signal Output end, the negative electrode of the voltage-stabiliser tube connect the input of the bleeder circuit.

Further, the voltage-regulator diode at least two, at least two voltage-regulator diodes are connected in parallel.

A kind of electronic equipment, including power supply, lamp bar and driving are provided according to the second aspect of the embodiment of the present disclosure The driving chip of the lamp bar work, the electronic equipment also include above-mentioned protection circuit；The protection circuit is used to protect The driving chip.

The protection circuit and electronic equipment of the embodiment of the present disclosure, by setting the external electricals such as bleeder circuit and on-off circuit Road, when the signal for the signal output part that lamp bar generation short circuit or other abnormal conditions cause to be connected with lamp bar negative pole is excessive, For the voltage of driving chip signal output part after bleeder circuit carries out partial pressure, trigger switch circuit output makes driving chip stop work The branch pressure voltage of work, and then avoid driving chip from being damaged because temperature is too high, cause electronic equipment to be stopped.Circuit structure letter List, cost are low.In addition, in the periphery increase bleeder circuit and on-off circuit of driving chip, can also be according to different output electricity When pressing (i.e. the voltage of signal output part) flexibly adjust lamp bar short circuit, the detecting voltage of bleeder circuit and on-off circuit is realized Short-circuit protection.

It should be appreciated that the general description and following detailed description of the above are only exemplary and explanatory, not The disclosure can be limited.

Brief description of the drawings

Accompanying drawing herein is merged in specification and forms the part of this specification, shows and meets disclosure implementation Example, and for explaining principle of the invention together with specification.

Fig. 1 is a kind of structured flowchart of protection circuit shown in the exemplary embodiment of the disclosure one；

Fig. 2 is the structured flowchart of another protection circuit shown in the exemplary embodiment of the disclosure one；

Fig. 3 is a kind of structural representation of protection circuit shown in the exemplary embodiment of the disclosure one；

Fig. 4 is the structural representation of another protection circuit shown in the exemplary embodiment of the disclosure one；

Fig. 5 is the structural representation of another protection circuit shown in the exemplary embodiment of the disclosure one；

Fig. 6 is the structured flowchart of a kind of electronic equipment shown in the exemplary embodiment of the disclosure one；

Fig. 7 is the structured flowchart of another electronic equipment shown in the exemplary embodiment of the disclosure one.

Embodiment

Here exemplary embodiment will be illustrated in detail, its example is illustrated in the accompanying drawings.Following description is related to During accompanying drawing, unless otherwise indicated, the same numbers in different accompanying drawings represent same or analogous key element.Following exemplary embodiment Described in embodiment do not represent all embodiments consistent with the disclosure.On the contrary, they be only with it is such as appended The example of the consistent apparatus and method of some aspects be described in detail in claims, the disclosure.

It is only merely for the purpose of description specific embodiment in the term that the disclosure uses, and is not intended to be limiting the disclosure. " one kind " of singulative used in disclosure and the accompanying claims book, " described " and "the" are also intended to including majority Form, unless context clearly shows that other implications.

Fig. 1 is a kind of structured flowchart of protection circuit 10 of the exemplary embodiment of the disclosure one.The protection circuit 10 is used for Driving chip 20 is protected, driving chip 20 is used to drive lamp bar 30 to work, and the protection circuit 10 includes bleeder circuit 12 and switch Circuit 13.Wherein, the negative pole 32 of lamp bar 30 connects the signal output part 21 of driving chip 20, the connection power supply of positive pole 31 of lamp bar 30 Power supply 40.Signal output part 21 is also connected with the input of bleeder circuit 12, the output end connecting valve circuit 13 of bleeder circuit 12 Input, on-off circuit 13 output end connection driving chip 20 Enable Pin 22.

Wherein, when the signal of signal output part 21 is more than or equal to preset value, bleeder circuit 12 is by signal output part 21 Signal carry out partial pressure after the branch pressure voltage trigger switch circuit 13 that exports work, on-off circuit 13, which exports, causes driving chip 20 The signal being stopped is to Enable Pin 22.

The present embodiment by setting bleeder circuit 12 and the grade external circuit of on-off circuit 13, lamp bar 30 occur short circuit or When other abnormal conditions of person cause the signal for the signal output part 21 being connected with the negative pole of lamp bar 30 32 excessive, driving chip 20 For the voltage of signal output part 21 after bleeder circuit 12 carries out partial pressure, the output of trigger switch circuit 13 makes driving chip 20 stop work The branch pressure voltage of work, and then avoid driving chip 20 from being damaged because temperature is too high, cause electronic equipment to be stopped, circuit structure Simply, cost is low.In addition, in the periphery increase bleeder circuit 12 and on-off circuit 13 of driving core 20, can also be according to different Output voltage (i.e. the voltage of signal output part) when flexibly adjustment lamp bar 30 is short-circuit, detect by bleeder circuit 12 and on-off circuit 13 Voltage is surveyed to realize short-circuit protection.

Wherein, the preset value can be the signal output part for causing driving chip 20 to be located at safe temperature (such as 130 °) 21 critical voltage or current value.Alternatively, preset value selection is 24V, when the voltage of the signal output part 21 of driving chip 20 During more than or equal to 24V, the temperature of driving chip 20 exceedes the risk increase of safe temperature, and driving chip 20 faces what is burnt out Possibility can also increase, thus be necessary to stop the work of driving chip 20.

In the embodiment of the present disclosure, lamp bar 30 can include the LED luminous two that multiple (at least two) are connected in series Pole pipe.

During 30 normal work of lamp bar, power supply 40 can provide the positive pole 31 of lamp bar 30 lamp bar 30 and work required work Voltage, the signal output part 21 of driving chip 20 export the voltage signal of very little (being approximately 0) to the negative pole 21 of lamp bar 30.This When, the voltage that is exported after bleeder circuit 12 also very little, then it is unable to trigger switch circuit 13 and works.And when the short circuit of lamp bar 30 or When other abnormal conditions occur, it is very big to may result in the signal (such as voltage signal) of the signal output part 21 of driving chip 20, When the signal of signal output part 21 is more than preset value, bleeder circuit 12 exports after the voltage of signal output part 21 is carried out into partial pressure Branch pressure voltage can trigger switch circuit 13 work, on-off circuit 13 can then export so that the letter that driving chip 20 is stopped Number to Enable Pin 22, driving chip 20 is set to be stopped, so as to prevent that driving chip 20 is excessive because of the voltage of signal output part 21 And burn out.

Fig. 2 is the structured flowchart of another protection circuit 10 of the exemplary embodiment of the disclosure one.As shown in Fig. 2 this public affairs Opening the protection circuit 10 of embodiment also includes mu balanced circuit 11, and the mu balanced circuit 11 is located at signal output part 21 and bleeder circuit 12 Input between so that input to bleeder circuit 12 voltage it is relatively stable, so as to trigger switch circuit 13 export compared with Cause the signal that driving chip 20 ends work to the Enable Pin 22 of driving chip 20 for stable.Specifically, mu balanced circuit 11 Input connection signal output part 21, mu balanced circuit 11 output end connection bleeder circuit 12 input.

Fig. 3 is the structural representation of another protection circuit 10 shown in the exemplary embodiment of the disclosure one.Such as Fig. 3 institutes Show, bleeder circuit 12 can include first resistor R1 and second resistance R2.Wherein, first resistor R1 one end ground connection, the other end It is connected to the input of on-off circuit 13.The output end of second resistance R2 one end connection mu balanced circuit 11, the other end are connected to The input of on-off circuit 13.

In the present embodiment, first resistor R1 and second resistance R2 resistance can be according to the electricity of the positive pole 31 of lamp bar 30 input Press signal and set.Specifically, when the short circuit of lamp bar 30 or when there are other failures, bleeder circuit 12 is by signal output part 21 Voltage carry out after partial pressure the branch pressure voltage that exports can trigger switch circuit 13 work so that the output of on-off circuit 13 makes driving core The signal that piece 20 is stopped, so as to prevent driving chip 20 from being burnt because the voltage of signal output part 21 is excessive.When lamp bar 30 During normal work, the signal output part 21 of driving chip 20 exports the voltage signal of very little, and bleeder circuit 12 is by signal output part After 21 voltage carries out partial pressure, the branch pressure voltage of output will not trigger switch circuit 13 work, now, on-off circuit 13 is without output Signal.

Alternatively, voltage-regulator diode can be included with continued reference to Fig. 3, mu balanced circuit 11；The anode connection of voltage-regulator diode Signal output part 21, the input of the negative electrode connection bleeder circuit 12 of voltage-regulator diode.So, the letter that signal output part 21 exports Number stable voltage signal is exported to bleeder circuit 12 through voltage-regulator diode, avoid the swinging of signal exported when signal output part 21 Regularly, cause triode by false triggering, or cause triode breakdown.

Alternatively, Fig. 4 is the structural representation of another protection circuit 10 shown in the exemplary embodiment of the disclosure one, such as Shown in Fig. 4, voltage-regulator diode can be at least two, and at least two voltage-regulator diodes can be connected in parallel.In an optional realization In mode, at least two voltage-stabiliser tubes are two, with reference to figure 4.Wherein, the anode of two voltage-stabiliser tubes is connected, the moon of two voltage-stabiliser tubes Extremely it is connected, so as to realize the parallel connection of two voltage-stabiliser tubes.The signal that driving chip 20 is connected after the anode parallel connection of two voltage-stabiliser tubes is defeated Go out end 21, the input of bleeder circuit 12 is connected after the negative electrode parallel connection of two voltage-stabiliser tubes.

In the embodiment of the present disclosure, with continued reference to Fig. 3, on-off circuit 13 can include triode, the input of on-off circuit 13 End is the base stage b of triode, and the output end of on-off circuit 13 is the colelctor electrode c of triode.Wherein, the base stage b connections of triode The output end of bleeder circuit 12, the Enable Pin 22 of the colelctor electrode c connections driving chip 20 of triode.

In some instances, during the 22 input low level signal of Enable Pin of driving chip 20, driving chip 20 is locked, from And it is stopped；During the 22 input high level signal of Enable Pin of driving chip 20, driving chip 20 is in running order.It is optional Ground, referring to Fig. 3, the emitter e of triode is grounded, and the Enable Pin 22 of driving chip 20 stops work in input low level signal Make, what now on-off circuit 13 exported make it that the signal that driving chip 20 is stopped is low level signal.So, signal is defeated When going out to hold 21 signal to be more than or equal to preset value (short circuit may occur for lamp bar 30), now, what bleeder circuit 12 exported divides Piezoelectricity pressure can make triode ON, because the emitter e of triode is grounded, cause the Enable Pin 22 of driving chip 20 to be pulled low, Driving chip 20 is set to be stopped.

In some other example, during the 22 input high level signal of Enable Pin of driving chip 20, driving chip 20 is locked Extremely, so as to being stopped；During the 22 input low level signal of Enable Pin of driving chip 20, driving chip 20 is in running order. Alternatively, the emitter e of triode can also connect voltage source.The Enable Pin 22 of driving chip 20 is when receiving high level signal It is stopped, what now on-off circuit 13 exported make it that the signal that driving chip 20 is stopped is high level signal.So, When the signal of signal output part 21 is more than or equal to preset value, bleeder circuit 12 divides the voltage of signal output part 21 Pressure, the branch pressure voltage of output can make triode ON, cause the Enable Pin 22 of driving chip 20 to be driven high, so that driving core Piece 20 is stopped.

Optionally, with reference to figure 4, as shown in figure 4, on-off circuit 13 can include metal-oxide semiconductor (MOS) metal-oxide-semiconductor.Switch The input of circuit 13 is the grid G of metal-oxide-semiconductor, and the output end of on-off circuit 13 is the drain D of metal-oxide-semiconductor.Wherein, the grid of metal-oxide-semiconductor The output end of pole G connection bleeder circuits, the Enable Pin 22 of the drain D connection driving chip 20 of metal-oxide-semiconductor.

In some instances, during the 22 input low level signal of Enable Pin of driving chip 20, driving chip 20 is locked, from And it is stopped；During the 22 input high level signal of Enable Pin of driving chip 20, driving chip 20 is in running order.It is optional Ground, referring to Fig. 4, the source S of metal-oxide-semiconductor is grounded, and the Enable Pin 22 of driving chip 20 is stopped in input low level signal, this When on-off circuit 13 export make it that the signal that is stopped of driving chip 20 is low level signal.So, in signal output When the signal at end 21 is more than or equal to preset value (short circuit may occur for lamp bar 30), now, the partial pressure that bleeder circuit 12 exports Voltage can turn on metal-oxide-semiconductor, because the source S of metal-oxide-semiconductor is grounded, causes the Enable Pin 22 of driving chip 20 to be pulled low, make driving Chip 20 is stopped.

In some other example, during the 22 input high level signal of Enable Pin of driving chip 20, driving chip 20 is locked Extremely, so as to being stopped；During the 22 input low level signal of Enable Pin of driving chip 20, driving chip 20 is in running order. Alternatively, the source S of metal-oxide-semiconductor can also connect voltage source, and the Enable Pin 22 of driving chip 20 is stopped when receiving high level signal Only work, what now on-off circuit 13 exported make it that the signal that driving chip 20 is stopped is high level signal.

So, when the signal of signal output part 21 is more than or equal to preset value, bleeder circuit 12 is to signal output part 21 Voltage carry out partial pressure, the branch pressure voltage of output can turn on metal-oxide-semiconductor, cause the Enable Pin 22 of driving chip 20 to be driven high, from And the driving chip 20 made is stopped.

In the embodiment of the present disclosure, the output end of bleeder circuit 12 is also associated with filter circuit.Alternatively, referring to Fig. 5, filtering Circuit includes the electric capacity C of ground connection.By setting electric capacity C, the voltage signal that can be exported to bleeder circuit 12 is filtered, with defeated Go out more stable branch pressure voltage.Alternatively, filter circuit can also be RC filter circuits, so that bleeder circuit output is steady Fixed branch pressure voltage.

It is noted that the protection circuit 10 of the embodiment of the present disclosure can be applied to electronic equipment.Alternatively, lamp bar 30 can Used as backlight, and the back of the body can be provided for the display screen in electronic equipment (such as liquid crystal TV set, game machine, mobile phone) Light.

Fig. 6 is the structured flowchart of a kind of electronic equipment shown in the exemplary embodiment of the disclosure one.Referring to Fig. 6, electronics is set Guarantor shown in the standby driving chip 20 to be worked including power supply 40, lamp bar 30, driving lamp bar 30 and above-mentioned diagram embodiment Protection circuit 10, protection circuit 10 are used to protect driving chip 20.

In an optional embodiment, with reference to figure 6, driving chip 20 includes a signal output part 21, and lamp bar 30 is just Pole 31 connects power supply 40, and negative pole 32 connects the signal output part 21, and signal output part 21 is also connected with the defeated of protection circuit 10 Enter end, the Enable Pin 22 of the output end connection driving chip 20 of protection circuit 10.In the present embodiment, when lamp bar 30 occur short circuit or When the signal of signal output part 21 is more than preset value caused by other failures of person, the output of protection circuit 10 stops driving chip 20 The signal of work, to avoid the temperature of driving chip 20 too high.When i.e., the present embodiment exports available for the single channel of driving chip 20 ( The connection of driving chip 20 lamp bar 30 all the way) backlight short circuit and other error protections.

In another optional embodiment, with reference to figure 7, driving chip 20 can include multiple signal output parts, Mei Gexin Number output end connects the negative pole of a lamp bar, and each signal output part connects the input of a protection circuit 10, in Fig. 7 with Illustrated exemplified by 3 signal output parts, wherein signal output part 21 connects the negative pole 32 of lamp bar 30, and signal output part 23 connects The negative pole 52 of lamp bar 50, signal output part 24 connect lamp bar 60 negative pole 62, the positive pole 31 of lamp bar 30, the positive pole 51 of lamp bar 50 with And the positive pole 61 of lamp bar 60 all connects power supply 40；Signal output part 21 connects the input of a protection circuit 10, letter Number output end 23 connects the input of another protection circuit 10, and signal output part 24 connects the defeated of another protection circuit 10 Enter end, the output ends of three protection circuits 10 is all connected with the Enable Pin 22 of driving chip 20, when lamp bar 30, lamp bar in the present embodiment 50 either any one in lamp bar 60 occur signal output part 21 caused by short circuit or other failures signal be more than it is default During value, the output of control circuit 10 makes the signal that driving chip 20 is stopped, to avoid the temperature of driving chip 20 too high.I.e., originally Embodiment can be used for the backlight short circuit and other events of (driving chip 20 connects Multi-path lamp strip) during 20 multiple-channel output of driving chip Barrier protection.

The preferred embodiment of the disclosure is the foregoing is only, not limiting the disclosure, all essences in the disclosure God any modification, equivalent substitution and improvements done etc., should be included within the scope of disclosure protection with principle.

Claims (10)

1. a kind of protection circuit, for protecting driving chip, the driving chip is used to drive lamp bar to work, it is characterised in that The protection circuit includes bleeder circuit and on-off circuit；

The signal output part of the negative pole connection driving chip of the lamp bar, the positive pole connection power supply of the lamp bar；

The signal output part is also connected with the input of the bleeder circuit, and the output end of the bleeder circuit connects the switch The input of circuit, the output end of the on-off circuit connect the Enable Pin of the driving chip；

Wherein, when the signal of the signal output part is more than or equal to preset value, the bleeder circuit is by the signal output The branch pressure voltage that the signal at end exported after partial pressure triggers the on-off circuit work, and the on-off circuit is exported so that described The signal that driving chip is stopped is to the Enable Pin.

2. protection circuit according to claim 1, it is characterised in that the bleeder circuit includes first resistor and the second electricity Resistance；

One end ground connection of the first resistor, the other end are connected to the input of the on-off circuit；

One end of the second resistance connects the signal output part, and the other end is connected to the input of the on-off circuit.

3. protection circuit according to claim 1 or 2, it is characterised in that the on-off circuit includes triode；

The input of the on-off circuit is the base stage of the triode, and the output end of the on-off circuit is the triode Colelctor electrode.

4. protection circuit according to claim 3, it is characterised in that the grounded emitter of the triode.

5. protection circuit according to claim 1, it is characterised in that the on-off circuit includes metal-oxide semiconductor (MOS) Metal-oxide-semiconductor；

The input of the on-off circuit is the grid of the metal-oxide-semiconductor, and the output end of the on-off circuit is the leakage of the metal-oxide-semiconductor Pole.

6. protection circuit according to claim 5, it is characterised in that the source ground of the metal-oxide-semiconductor.

7. protection circuit according to claim 1, it is characterised in that the signal output part and the bleeder circuit it is defeated Enter and mu balanced circuit is additionally provided between holding, the input of the mu balanced circuit connects the signal output part, the mu balanced circuit Output end connects the input of the bleeder circuit.

8. protection circuit according to claim 7, it is characterised in that the mu balanced circuit includes voltage-regulator diode；

The anode of the voltage-regulator diode connects the signal output part, and the negative electrode of the voltage-stabiliser tube connects the bleeder circuit Input.

9. protection circuit according to claim 8, it is characterised in that the voltage-regulator diode at least two, at least two The voltage-regulator diode is connected in parallel.

10. a kind of electronic equipment, includes the driving chip of power supply, lamp bar and the driving lamp bar work, its feature exists In the electronic equipment also includes the protection circuit any one of claim 1 to 9；The protection circuit is used to protect The driving chip.