CN104617558B - Power supply short-circuit protective circuit - Google Patents
Power supply short-circuit protective circuit Download PDFInfo
- Publication number
- CN104617558B CN104617558B CN201310536030.XA CN201310536030A CN104617558B CN 104617558 B CN104617558 B CN 104617558B CN 201310536030 A CN201310536030 A CN 201310536030A CN 104617558 B CN104617558 B CN 104617558B
- Authority
- CN
- China
- Prior art keywords
- module
- delay
- output
- control
- power supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Protection Of Static Devices (AREA)
Abstract
The present invention provides a kind of power supply short-circuit protective circuit; it includes that voltage detection module, switch control module and delay keep module; it is detected using voltage detection module pair and the relevant voltage of output terminal shortcircuit of power supply; judge whether the output end of power supply generates short circuit based on the voltage detected; when being judged as that the output end of power supply generates short circuit, to the terminal output control signal for the output/stopping output pulse width modulated signal for controlling the control IC.According to the power supply short-circuit protective circuit; no matter whether the control IC in power circuit has short-circuit protection function; it so that control IC is stopped output pulse width modulated signal, realize the purpose of short-circuit protection, and the virtual value of the output current in power supply output short-circuit can be reduced.
Description
Technical field
The present invention relates to a kind of output short circuit protection circuits of power supply.
Background technology
Power supply is always one of the important guarantee that electric appliance runs well as the essential part of electric appliance.In particular,
Switching Power Supply has the characteristics that small, light-weight, high conversion efficiency, is widely used in Industry Control, communication office, family
In the various electronic equipments in fields such as consumption.Power supply is generally by being used for pulse width modulation（Pulse Width Modulation：
PWM）Control integrated circuit（Hereinafter referred to as in order to control IC）, the switch elements such as power field effect transistor or triode with
And the elements such as transformer are constituted.
According to the difference of electronic equipment, power supply used in the electronic equipment also uses different technical specification and index,
The especially technical specification and index of the various defencive functions such as overvoltage, overheat.When the load of power supply is broken down, output electricity
It flows to toward will increase, results even in output end and short circuit occurs, at this time, it may be necessary to which promptly power cutoff, prevents excessive electric current
Burn out the other elements or circuit of equipment.Therefore, output short circuit protection function receives pass as the critically important function of power supply
Note.
In order to reach short-circuit protection purpose, in general, control IC can pair with output end voltage or the relevant signal of electric current into
Row detection, and judge whether short-circuit state occur, to stop output or output pwm signal.Currently, much control IC itself just has
The overpowering short-circuit protection function of standby primary side.It is with the primary side control IC voltage values of detection reflection output end voltage
Example, as shown in Figure 1, there is short circuit in output end, and when short-circuit output power reaches primary side overpowering threshold value, transformer
For being begun to decline to the voltage at the both ends primary coil T1 of control IC power supplies, as a result, via resistance R7, rectifier diode D1
Decline with the voltage for the power end VCC for directly feeding control IC after smoothing capacity C3, when power end VCC drops to by controlling IC
When below defined threshold value, the short-circuit protection function work inside IC is controlled, stops output pwm signal, power supply is without output.
Wherein, two partial pressures of left part in Fig. 1 charge to capacitance C3 in power initiation with resistance R1, R2, with
Control IC is set to start.
However, in the case where the output of power supply is low-voltage, high current, for example, in output voltage in 5V hereinafter, output
In the case that electric current is 10A or more, when there is short circuit in the output end of power circuit, since the leakage inductance of transformer is big, Huo Zheci
The grade reasons such as short-circuit output impedance is excessive, although the variation of output power has reached the overpowering threshold value of primary side when short circuit,
But the voltage at the both ends primary coil T1 of the transformer in Fig. 1, which can not drop to, makes control IC stopping output pwm signals
Even defined threshold value is hereinafter, the control IC for having the overpowering short-circuit protection function of primary side can not realize short-circuit guarantor
Shield.
For another example, when power supply is multiple-channel output, there is the case where short circuit, other road output no-loads in output all the way wherein
Under, although short-circuit output power can make the primary side of power supply reach overpowering threshold value, the control IC's of primary side
The voltage of power end VCC cannot drop to the defined threshold value for making control IC stop output pwm signal or less.Even having just
The control IC of the overpowering short-circuit protection function in grade side can not realize short-circuit protection.
Invention content
Present invention has been made in view of the above problems, and the object of the present invention is to provide a kind of output ends in power supply
Generate the power protecting circuit that can reliably make control IC stop output pulse width modulated signal when short circuit.
A technical solution according to the present invention, the present invention provide a kind of power supply short-circuit protective circuit, with for
When the output end of the power supply of the control IC of output pulse width modulated signal generates short circuit, the control IC is made to stop output pulse
Bandwidth modulation signals.The power supply short-circuit protective circuit includes：Voltage detection module, first input end and detection reflection power supply
Output end short-circuit state voltage terminal connection, the second input terminal with receive reference voltage terminal connect, be based on pair
The short-circuit conditions associated voltage and the reference voltage of the output end of the reflection power supply be compared as a result, from output end
Output detection judges signal；Delay keeps module, input terminal to be connect with the output end of the voltage detection module, based on described
Detection judges signal, from output end output switching signal；Switch control module, input terminal keep the defeated of module with the delay
Outlet connects, and output end is connect with the control terminal that the control IC exported/stopped output pulse width modulated signal is controlled, root
According to the switching signal for keeping module from the delay, the control is controlled from the output end output being connect with the control terminal
IC exports/stops the signal of output pulse width modulated signal.The delay keeps module to judge signal based on the detection, to
The switch control module exports the switching signal, and the switch control module prolongs according to the switching signal by described
When keep within the delay time of Module Specification, make control IC stopping output pulse width modulated signal, also, passing through
After the delay time, make the control IC output pulse width modulated signals.
Preferably, the voltage detection module has：The divider resistance that two or more is connected in series with is located at point of most upstream
The upstream end of piezoresistance is the first input end of the voltage detection module, is located at the downstream termination of the divider resistance of most downstream
Ground.To the comparing element that the voltage divided by the divider resistance and the reference voltage are compared, first end with
The tie point connection selected in more than one tie point between the divider resistance being connected in series with more than described two, the
Two ends are the second input terminal of the voltage detection module, and third end is the output end of the voltage detection module.
Preferably, the voltage detection module also has shunt capacitance, one end of the shunt capacitance and selected one
A tie point connection, other end ground connection.
Preferably, it includes the discharge resistance and capacitance being connected in parallel, the discharge resistance and institute that the delay, which keeps module,
The first tie point for stating capacitance is the output end that the delay keeps module, the second connection of the discharge resistance and the capacitance
Point ground connection, the delay keep the output end of module to keep the input terminal of module to connect with the delay.It is highly preferred that substitution institute
Stating delay keeps the output end of module to keep the input terminal of module to connect with the delay, additionally it is possible to keep module in the delay
Input terminal and it is described delay keep module output end between be also associated with charging resistor.
Preferably, the switch control module includes a switch element, and the first end of the switch element is described opens
The input terminal of control module is closed, second end is the output end of the switch control module, third end ground connection.
Preferably, the voltage detection module includes the first, second divider resistance being connected in series with for two of partial pressure
And a triode, one end of first divider resistance are the first input end of the voltage detection module, the other end with
One end of second divider resistance is connected with the base stage of the triode, the extremely described voltage detecting of transmitting of the triode
Second input terminal of module, the output end of the extremely described voltage detection module of current collection, another termination of second divider resistance
Ground.It includes a discharge resistance being connected in parallel and a capacitance, the discharge resistance and the electricity that the delay, which keeps module,
The first tie point held is that described be delayed keeps the output end of module, and the second tie point of the discharge resistance and the capacitance connects
Ground, the delay keep the output end of module to keep the input terminal of module to connect with the delay.The switch control module packet
A power field effect transistor is included, the grid of the power field effect transistor is the input terminal of the switch control module,
Drain electrode is the output end of the switch control module, source electrode ground connection.It is highly preferred that the voltage detection module also has, there are one other
Road capacitance, one end of the shunt capacitance are connect with the base stage of the triode, other end ground connection.In addition it is possible to replace described
Delay keeps the output end of module to keep the input terminal of module to connect with the delay, additionally it is possible to keep module in the delay
It is also associated with charging resistor between input terminal and the output end of the delay holding module.
Power supply short-circuit protective circuit according to the present invention, when short circuit occurs in the output end of power circuit, no matter power supply is electric
Whether the control IC in road has short-circuit protection function, can reliably stop the control IC for carrying out pulse width modulation
Output action, the virtual value of output current is greatly lowered, realizes the purpose of short-circuit protection.
Description of the drawings
Fig. 1 is the circuit diagram that the control IC itself for indicating in the prior art can realize short-circuit protection.
Fig. 2 is the schematic diagram for the module for indicating the power supply short-circuit protective circuit of the present invention
Fig. 3 is the circuit diagram for the concrete example for indicating the power supply short-circuit protective circuit of the present invention.
Fig. 4 be indicate shown in Fig. 3 power supply short-circuit protective circuit work under control IC power end voltage and
The oscillogram of the output current of circuit.
Specific implementation mode
With reference to attached drawing, the embodiment of the power supply short-circuit protective circuit 1 of the present invention is described in detail.Wherein, it is
Convenient for explanation, identical reference numeral is marked to identical element.
Fig. 2 is the schematic diagram for the module for indicating the power supply short-circuit protective circuit 1 of the present invention.Power supply short-circuit protective circuit 1 wraps
It includes：Voltage detection module 11, there are two input terminal and an output end, the power end VCC of first input end and control IC for tool
Connection, thus come detect control IC power end VCC voltage, the voltage of the power end VCC of control IC is for reflecting electricity
The voltage of the short-circuit state of the output end in source, the second input terminal is connect with the reference voltage terminal REF of control IC, by detecting
The voltage of power end VCC of control IC be compared with the voltage of reference voltage terminal REF, magnitude relationship based on comparative result
To judge signal from output end output detection；Delay keeps module 12, and there are one input terminal and an output end, input terminals for tool
It is connect with the output end of voltage detection module 11, delay keeps module 12 to judge letter based on the detection from voltage detection module 11
Number, from output end output switching signal；Switch control module 13, tool there are one input terminal and an output end, input terminal with
Delay keeps the output end connection of module 12, output end to connect, be based on the output control terminal CS of the output pwm signal of control IC
The switching signal that module 12 is kept from delay controls signal to the output control terminal CS outputs of the output pwm signal of control IC,
Output control terminal CS is the enabled terminal for controlling IC and exporting/stop output pwm signal, and delay keeps module 12 via the switch control
Molding block 13 carrys out the time that regulation control IC stops output pwm signal.In addition, voltage detection module 11, delay keep module 12
And switch control module 13 all has ground terminal.
Wherein, the output detection of module 12 is kept to judge that the mode of signal includes that output voltage etc. is a variety of and can transmit to delay
The mode of detection information, it may for example comprise output forward voltage, not output voltage and the mode for exporting backward voltage further include
By the signal for indicating detection information with it is prior as defined in threshold value be compared, according to indicate detection information signal size come into
The mode of row output.In addition, to 13 output switching signal of switch control module mode also include above-mentioned a variety of modes, only
It wants to realize and the state for making the state of control IC output pwm signals and control IC being made to stop output pwm signal being switched over
?.In the present embodiment, output detection judges that the mode of signal and output switching signal is all made of the high and low level of output
The mode of voltage.
In the case where the output end of power supply does not generate short circuit, the voltage for controlling the power end VCC of IC is normal work
Make voltage（For example, being 18.5V）, at this point, after the voltage of power end VCC is by the partial pressure inside voltage detection module 11
Voltage is higher than reference voltage terminal REF（For example, being 5V）Voltage, voltage detection module 11 exports low level detection and judges letter
Number, delay keeps module 12 to judge signal based on the low level detection, exports low level switching signal, as a result, switch control
Molding block 13 is based on the switching signal, not to the output control terminal CS output control signals of control IC, it is ensured that control IC exports PWM
Signal.On the other hand, in the case where the output end of power supply generates short circuit, the voltage for controlling the power end VCC of IC declines, power supply
Although the voltage of end VCC does not drop to the shutdown threshold voltage of control IC itself, but as long as the voltage of power end VCC is made to pass through
The voltage obtained after partial pressure inside voltage detection module 11（For example, in 4.4V or less）Voltage than reference voltage terminal REF
（For example, being 5V）Voltage value as defined in low（For example, being 0.6V）, then, the detection that voltage detection module 11 exports high level is sentenced
Break signal, hereafter, delay keep module 12 to export the switching signal of high level, and switch control module 13 is based on high level switch
Signal exports low level control signal to the output control terminal CS of control IC, and control IC stops output pwm signal.Therefore, energy
So that output current is fallen to 0, realizes the short-circuit protection of power output end.
Hereafter, it keeps the regulation control of module 12 IC to stop the time of output pwm signal by delay, is now passed through in fact by prolonging
When keep as defined in module 12 after the above-mentioned time, the output control terminal CS outputs that switch control module 13 stops to control IC are low
The control signal of level makes control IC output pwm signals again, output current rise again as a result,.Power supply output end still
It is old in the case of the short-circuit condition, voltage detection module 11 detects that the voltage of the power end VCC of control IC declines again, leads to
It crosses switch control module 13 and exports low level control signal to the output control terminal CS of control IC, to stop the defeated of control IC
Go out, if the output end of power supply is constantly in short-circuit condition, the output action of starting/closing control IC repeatedly, therefore, outlet chamber
Formula of having a rest electric current, to reduce the virtual value of output current.Restore normally the i.e. settled situation of short trouble in the output end of power supply
Under, power circuit reverts to normal working condition automatically.
Specifically, above-mentioned voltage detection module 11 by a pair of of partial pressure with resistance R3, R4 and a switch element come structure
At, but not limited to this, the power end VCC of control IC because of caused by the short circuit of output end can also be detected by other elements
Multiple resistance, switch element can also be arranged for example, partial pressure is not limited to only a pair with resistance in voltage change as needed
It can be replaced using other comparing elements with equivalent function, such as comparator etc..In the present embodiment, compare
Element uses the triode TR1 of positive-negative-positive, as shown in figure 3, one end of resistance R3 is connect with the power end VCC of control IC（In figure
A points）, the other end connect with one end of resistance R4, the other end ground connection of resistance R4, the intermediate point B and three of two resistance R3, R4
The base stage of pole pipe TR1 connects, the reference voltage terminal REF of the emitter and control IC of triode TR1（It is C points in figure）Connection, three
The collector of pole pipe TR1 is connect with the output end of voltage detection module 11.Voltage detection module 11 can also be included in B points and ground
A concatenated shunt capacitance C1 between GND, shunt capacitance C1 play the delay of voltage detecting to a certain degree.It prevents
Voltage detecting circuit malfunctions.
In addition, above-mentioned switch control module 13 is made of a switch element, in the present embodiment, imitated using power field
Transistor TR2 is answered, but not limited to this, other members with the function equivalent with power field effect transistor TR2 can also be used
The combination etc. of part or element.In the present embodiment, as shown in figure 3, the grid of power field effect transistor TR2（It is D in figure
Point）It is connect with the input terminal of switch control module 13, i.e., keeps the output end of module 12 to connect with delay, power field effect crystal
The drain electrode of pipe TR2 is connect with the output control terminal CS of control IC（It is E points in figure）, the source electrode of power field effect transistor TR2 connects
Ground.
In addition, it includes the discharge resistance R6 being connected in parallel and capacitance C2, capacitance C2 and electric discharge that above-mentioned delay, which keeps module 12,
One end of resistance R6 parallel connections keeps the output end of module 12 to connect with delay, another termination in parallel with discharge resistance R6 capacitance C2
Ground.Furthermore it is preferred that the delay keeps module 12 that can also connect a charging resistor R5 between input terminal and output end.
In the present embodiment, as shown in figure 3, one end of charging resistor R5 is connect with the collector of triode TR1, the other end and capacitance
Above-mentioned one end of C2 and the grid connection of power field effect transistor TR2, utilize the charging of charging resistor R5 and capacitance C2
Time constant was adjusted to the time of capacitance C2 charging.It, can be by charging resistor R5's in order to ensure the charging current of capacitance C2
Value is set as being much smaller than discharge resistance R6, wherein discharge resistance R6 is for discharging to capacitance C2.Module 12 is kept in delay
In the case of not including charging resistor R5, which keeps the input terminal of module 12 to be connect with output end, that is, capacitance C2's is above-mentioned
One end not only kept the input terminal of module 12 to connect with delay, but also kept the output end of module 12 to connect with delay.In this embodiment party
In formula, in the case where it includes charging resistor R5 that delay, which keeps module 12 not, the collection of above-mentioned one end and triode TR1 of capacitance C2
The grid of electrode and power field effect transistor TR2 connect.
In the following, with reference to Fig. 3, illustrated for the action process of power supply short-circuit protective circuit 1.It is produced in the output end of power supply
In the case of raw short circuit, voltage detection module 11 detects that the voltage of A points declines, and is obtained by two resistance R3, R4 partial pressures
The voltage of B points also decline.When the voltage of B points drops to the voltage of i.e. B points lower 0.6V or less than the voltage of C point in 4.4V or less
When, triode TR1 conductings.At this point, the detection that the voltage of the 5V of C points is exported via triode TR1 as voltage detection module 11
Judge that signal supply delay keeps the input terminal of module 12.The voltage of the 5V charges to capacitance C2 via charging resistor R5,
When the voltage of the voltage, that is, D points at the both ends capacitance C2（It is equivalent to the switching signal that delay keeps module 12 to export）It is promoted to and is higher than
The threshold voltage of power field effect transistor TR2 conductings included by switch control module 13（For example, being 1V）When, power field effect
It answers transistor TR2 to be connected, the voltage of E points is made to drop to low level（1V or less）, therefore, switch control module 13 exports low level
Control signal, make control IC stop output pwm signal, thereby, it is possible to realize the short-circuit protection of output end.
Hereafter, since control IC stops output pwm signal, control IC power consumption reduces, meanwhile, by the exchange from power supply
The DC voltage obtained after the ac voltage rectifier at end charges via resistance R1 to smoothing capacity C3, controls the power supply of IC
The voltage of end VCC rises again.Therewith, the voltage of B points also rises therewith, when the voltage of B points rises to 4.4V or more, three poles
Pipe TR1 becomes ending from conducting, at this point, the voltage of D points remains above the on state threshold voltage of power field effect transistor TR2.This
Afterwards, since triode TR1 ends, the voltage for the 5V that the reference voltage terminal by controlling IC provides will not be supplied via charging resistor R5
Capacitance C2 so capacitance C2 is no longer electrically charged, but starts to discharge via discharge resistance R6, and the voltage of D points is begun to decline.Work as D
When the voltage of point drops below the on state threshold voltage of power field effect transistor TR2, power field effect transistor TR2 is also cut
Only, the low level of voltage, that is, E points of the output control terminal CS of control IC is released as a result, so that control IC exports PWM letters again
Number, output current rises again.
In this case, as described above, in the case where the output end of power supply remains in short-circuit condition, the voltage of B points
Decline again, triode TR1 is made to be connected again, hereafter, power field effect transistor TR2 is made also to be connected again, drop-down control IC
Output control terminal CS voltage, make control IC stop output.Since the output end of power supply is constantly in short-circuit condition, or more
The output action of the starting stated/closing control IC continues, as shown in figure 4, the voltage of the power end VCC of control IC is in sawtooth
The output end of wavy raising/decline repeatedly, power supply is exported with the period identical with the control period of waves of power end VCC of IC
Intermittent electric current.Since intermittent electric current only circulates in moment, so the virtual value of output current entirety is very low.
Here, can be by keeping the parameter of the capacitance C2 and discharge resistance R6 of module 12 to adjust to constituting to be delayed in advance
Section, carrys out the constant conduction time t1 of regulation power field effect transistor TR2, that is, regulation makes control IC persistently stop exporting in advance
The time of pwm signal, the virtual value of the intermittent electric current exported in short circuit so as to allocated circuit.Discharge resistance R6 or electricity
The size for holding the value of C2 determines the length of constant conduction time t1, for example, in the case where triode TR1 is connected, the voltage of D points
It is about 5V（It is approximately equal to the voltage of the reference voltage terminal REF of control IC）If discharge resistance R6 is set as 1M Ω, capacitance C2 is set
For 1 μ F, then it is 98.4ms to determine constant conduction time t1；In the case where discharge resistance R6 is constant, if capacitance C2 is set as 2
It is elongated to 160.8ms then to determine constant conduction time t1 by μ F, that is to say, that control IC persistently stop output pwm signal when
Between it is elongated.The virtual value for reducing the intermittent electric current that power supply is exported in short circuit as a result, further functions as the output in power supply
Protective effect when terminal shortcircuit.
In the present embodiment, power supply short-circuit protective circuit be by directly to control IC power end VCC voltage into
Row detection, to judge whether the output end of power supply produces short circuit.But not limited to this, for example, it is also possible to by controlling IC
The voltage of feedback end FB be detected, judge to carry out the short circuit of output end of power supply.In the present embodiment, pass through control
The reference voltage terminal REF of IC receives reference voltage, but not limited to this, benchmark electricity can also be generated by another way
Pressure.In addition, being by the way that IC will be controlled in the case where detecting that the output end of power supply produces short circuit in the present embodiment
Output control terminal CS be set to low level mode, to make control IC stop output pwm signal, but not limited to this.
More than, embodiments of the present invention are illustrated.As described above, there is short circuit in the output end in power circuit
When, in the case that control IC in a power does not have short-circuit protection function, power source short-circuit protection electricity according to the present invention
Road can stop the output action of the control IC for carrying out pulse width modulation, the virtual value of output current is greatly lowered,
Realize the purpose of short-circuit protection.In addition, the leakage inductance due to transformer is big or secondary short circuited output impedance is excessive or multichannel
The reasons such as the case where single output is short-circuited in out-put supply so that the variation of output power cannot reach primary side when short-circuit
The threshold value of overpower protection, so even if not starting the feelings of above-mentioned short-circuit protection function in the control IC for having short-circuit protection function
Under condition, the power supply short-circuit protective circuit of the present invention can be equally applied, to be reliably achieved the purpose of short-circuit protection.
In addition, the present invention do not depart from the present invention broad sense thought and range under the premise of can carry out it is various
Embodiment and deformation.In addition, above-mentioned embodiment is used to illustrate the present invention, but do not limit the scope of the present invention.
Claims (8)
1. a kind of power supply short-circuit protective circuit, in the defeated of the power supply with the control IC for output pulse width modulated signal
When outlet generates short circuit, the control IC is made to stop output pulse width modulated signal, which is characterized in that
Including：
Voltage detection module, first input end are connect with power supply terminal, and the second input terminal connects with the terminal for receiving reference voltage
Connect, based on to the power supply terminal voltage and the reference voltage be compared as a result, from output end export detection judge
Signal,
Delay keeps module, input terminal to be connect with the output end of the voltage detection module, judges signal based on the detection,
From output end output switching signal,
Switch control module, input terminal keep the output end of module to connect with the delay, output end and the control control
IC exports/stops the control terminal connection of output pulse width modulated signal, according to the switch for keeping module from the delay
Signal controls the control IC from the output end output being connect with the control terminal and exports/stop output pulse width modulation
The signal of signal；
The delay keeps module to judge signal based on the detection, and the switching signal is exported to the switch control module,
The switch control module keeps within the delay time of Module Specification by the delay according to the switching signal, makes institute
It states control IC and stops output pulse width modulated signal, also, after by the delay time, the control IC is made to export
Pulse width modulating signal,
The voltage detection module includes the first, second divider resistance being connected in series with for two of partial pressure and three poles
Pipe, one end of first divider resistance are the first input end of the voltage detection module, and the other end is divided with described second
One end of resistance is connected with the base stage of the triode, and the second of the extremely described voltage detection module of transmitting of the triode is defeated
Enter end, the output end of the extremely described voltage detection module of current collection, the other end ground connection of second divider resistance.
2. power supply short-circuit protective circuit as described in claim 1, which is characterized in that
It includes the discharge resistance and capacitance being connected in parallel that the delay, which keeps module, and the first of the discharge resistance and the capacitance
Tie point is the output end that the delay keeps module, and the second tie point ground connection of the discharge resistance and the capacitance is described
Delay keeps the output end of module to keep the input terminal of module to connect with the delay.
3. power supply short-circuit protective circuit as described in claim 1, which is characterized in that
It includes the discharge resistance and capacitance being connected in parallel that the delay, which keeps module, and the first of the discharge resistance and the capacitance
Tie point is the output end that the delay keeps module, the second tie point ground connection of the discharge resistance and the capacitance, in institute
Delay is stated to keep being also associated with charging resistor between the input terminal of module and the output end of the delay holding module.
4. power supply short-circuit protective circuit as described in claim 1, which is characterized in that
The switch control module includes a switch element, and the first end of the switch element is the switch control module
Input terminal, second end are the output end of the switch control module, third end ground connection.
5. a kind of power supply short-circuit protective circuit, in the defeated of the power supply with the control IC for output pulse width modulated signal
When outlet generates short circuit, the control IC is made to stop output pulse width modulated signal, which is characterized in that
Including：
Voltage detection module, first input end are connect with power supply terminal, and the second input terminal connects with the terminal for receiving reference voltage
Connect, based on to the power supply terminal voltage and the reference voltage be compared as a result, from output end export detection judge
Signal,
Delay keeps module, input terminal to be connect with the output end of the voltage detection module, judges signal based on the detection,
From output end output switching signal,
Switch control module, input terminal keep the output end of module to connect with the delay, output end and the control control
IC exports/stops the control terminal connection of output pulse width modulated signal, according to the switch for keeping module from the delay
Signal controls the control IC from the output end output being connect with the control terminal and exports/stop output pulse width modulation
The signal of signal；
The delay keeps module to judge signal based on the detection, and the switching signal is exported to the switch control module,
The switch control module keeps within the delay time of Module Specification by the delay according to the switching signal, makes institute
It states control IC and stops output pulse width modulated signal, also, after by the delay time, the control IC is made to export
Pulse width modulating signal,
The voltage detection module includes for two of partial pressure the first, second divider resistances being connected in series with, a triode
And a shunt capacitance, one end of first divider resistance are the first input end of the voltage detection module, the other end
It is connect with the base stage of one end of second divider resistance and the triode, the extremely described voltage inspection of transmitting of the triode
Survey the second input terminal of module, the output end of the extremely described voltage detection module of current collection, the other end of second divider resistance
Ground connection, one end of the shunt capacitance are connect with the base stage of the triode, other end ground connection.
6. power supply short-circuit protective circuit as claimed in claim 5, which is characterized in that
It includes the discharge resistance and capacitance being connected in parallel that the delay, which keeps module, and the first of the discharge resistance and the capacitance
Tie point is the output end that the delay keeps module, and the second tie point ground connection of the discharge resistance and the capacitance is described
Delay keeps the output end of module to keep the input terminal of module to connect with the delay.
7. power supply short-circuit protective circuit as claimed in claim 5, which is characterized in that
It includes the discharge resistance and capacitance being connected in parallel that the delay, which keeps module, and the first of the discharge resistance and the capacitance
Tie point is the output end that the delay keeps module, the second tie point ground connection of the discharge resistance and the capacitance, in institute
Delay is stated to keep being also associated with charging resistor between the input terminal of module and the output end of the delay holding module.
8. power supply short-circuit protective circuit as claimed in claim 5, which is characterized in that
The switch control module includes a switch element, and the first end of the switch element is the switch control module
Input terminal, second end are the output end of the switch control module, third end ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310536030.XA CN104617558B (en) | 2013-11-01 | 2013-11-01 | Power supply short-circuit protective circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310536030.XA CN104617558B (en) | 2013-11-01 | 2013-11-01 | Power supply short-circuit protective circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104617558A CN104617558A (en) | 2015-05-13 |
| CN104617558B true CN104617558B (en) | 2018-10-30 |
Family
ID=53151899
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310536030.XA Expired - Fee Related CN104617558B (en) | 2013-11-01 | 2013-11-01 | Power supply short-circuit protective circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104617558B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102017214205A1 (en) | 2017-08-15 | 2019-02-21 | Robert Bosch Gmbh | Control unit with circuit and method for short-circuit protection of ground lines and sensors |
| CN109510958A (en) * | 2018-11-30 | 2019-03-22 | 惠州华科电器有限公司 | Short-circuit protection circuit and short circuit protection system |
| CN110994559B (en) * | 2019-12-06 | 2022-05-03 | 河南嘉晨智能控制股份有限公司 | Power module output end short-circuit protection circuit |
| CN111426932A (en) * | 2020-05-14 | 2020-07-17 | 深圳青铜剑技术有限公司 | Power semiconductor device driving power supply short circuit detection circuit |
| CN112018731B (en) * | 2020-07-08 | 2022-08-16 | 中车株洲电力机车研究所有限公司 | Monitoring method, device and system for rectifying and filtering device |
| CN112134257B (en) * | 2020-09-24 | 2023-05-12 | 深圳市信锐网科技术有限公司 | DC power supply short-circuit protection circuit |
| CN114597863B (en) * | 2022-03-07 | 2024-02-20 | 潍柴动力股份有限公司 | Power protection circuit |
| CN115940362B (en) * | 2023-02-08 | 2023-06-09 | 深圳市科宇电源科技有限公司 | Self-adaptive adjusting power supply circuit and self-adaptive adjusting method |
| CN119125962A (en) * | 2024-08-15 | 2024-12-13 | 山西高科华杰光电科技股份有限公司 | A circuit for detecting abnormality of LED module |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2919675Y (en) * | 2005-10-13 | 2007-07-04 | 深圳桑达百利电器有限公司 | DC-AC convertor |
| CN201408985Y (en) * | 2009-04-17 | 2010-02-17 | 中兴通讯股份有限公司 | Short circuit protection circuit for switching power supply |
| CN201813147U (en) * | 2010-10-09 | 2011-04-27 | Bcd半导体制造有限公司 | A short-circuit protection circuit for switching power supply |
| CN102280861A (en) * | 2011-08-01 | 2011-12-14 | 广州金升阳科技有限公司 | Output short-circuit protection circuit of switching power supply |
-
2013
- 2013-11-01 CN CN201310536030.XA patent/CN104617558B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2919675Y (en) * | 2005-10-13 | 2007-07-04 | 深圳桑达百利电器有限公司 | DC-AC convertor |
| CN201408985Y (en) * | 2009-04-17 | 2010-02-17 | 中兴通讯股份有限公司 | Short circuit protection circuit for switching power supply |
| CN201813147U (en) * | 2010-10-09 | 2011-04-27 | Bcd半导体制造有限公司 | A short-circuit protection circuit for switching power supply |
| CN102280861A (en) * | 2011-08-01 | 2011-12-14 | 广州金升阳科技有限公司 | Output short-circuit protection circuit of switching power supply |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104617558A (en) | 2015-05-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104617558B (en) | Power supply short-circuit protective circuit | |
| EP2793276B1 (en) | Led lamp, lighting device including led lamp, and method for controlling electric current of led lamp | |
| US8796943B2 (en) | LED lamp and illumination device including the LED lamp | |
| CN102111070B (en) | The regulator over-voltage protection circuit that standby current reduces | |
| US20160126718A1 (en) | Semiconductor device | |
| CN103327694B (en) | Silicon controlled dimming LED drive circuit | |
| CN110071638A (en) | Switching power unit and continuous-current plant | |
| JP5919506B2 (en) | Rechargeable electrical equipment | |
| EP2745368B1 (en) | Start-up circuit | |
| CN206249131U (en) | Power protecting circuit and supply unit | |
| CN202856607U (en) | Control circuit and switching converter | |
| CN101957413A (en) | Relay protection device detection circuit | |
| CN103917028A (en) | LED constant-current source and control method thereof | |
| CN203734296U (en) | Power supply short circuit protection circuit | |
| CN106936302A (en) | Electronic circuit and the method for operating electronic circuit | |
| CN104901574A (en) | Bridge circuit and short circuit protection method thereof | |
| KR102365558B1 (en) | Apparatus for removing afterglow of led lighting device, and led lighting device and apparatus for driving led lighting with the same | |
| CN103889114A (en) | LED dimming and driving circuit | |
| CN103796389B (en) | High-high brightness hoisting module, controllable silicon light modulation LED drive circuit and system | |
| CN103692058B (en) | With the soft-start circuit of power factor correction circuit inverter type welder | |
| CN107070190B (en) | Power supply device and capacitance heating control method thereof | |
| CN108574323A (en) | A kind of battery charge control circuit | |
| CN209375119U (en) | A kind of protection hiccup circuit | |
| CN105449995B (en) | Drive control circuit and drive control method and Switching Power Supply | |
| CN109873561A (en) | A kind of the energy utilization circuit and electronic equipment of overshoot voltage |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20181030 |