CN206533294U - Power supply overheat protector controls circuit and power supply - Google Patents
Power supply overheat protector controls circuit and power supply Download PDFInfo
- Publication number
- CN206533294U CN206533294U CN201621444411.0U CN201621444411U CN206533294U CN 206533294 U CN206533294 U CN 206533294U CN 201621444411 U CN201621444411 U CN 201621444411U CN 206533294 U CN206533294 U CN 206533294U
- Authority
- CN
- China
- Prior art keywords
- power supply
- resistance
- circuit
- voltage
- output
- 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.)
- Active
Links
Landscapes
- Control Of Voltage And Current In General (AREA)
Abstract
The utility model is related to power supply overheat protector control circuit and power supply, and protection control circuit includes the vice-side winding of transformer；It is connected with the vice-side winding of transformer, receives the secondary voltage of vice-side winding output and export the current rectifying and wave filtering circuit of output voltage；It is connected between current rectifying and wave filtering circuit and the negative terminal of power output end, the sample circuit of sampled voltage is sampled and exported to output voltage；The arithmetic control circuit being connected with sample circuit, arithmetic control circuit produces reference voltage；It is connected with arithmetic control circuit, the bleeder circuit of voltage division signal is exported based on reference voltage；The temperature detection control circuit being connected with bleeder circuit.This programme makes power supply when there are the abnormal conditions of excess temperature by increasing temperature detection control circuit, reduce the output current of power supply, the reduction to output power of power supply is realized to reduce the temperature of power supply and load, the problem of device failure and light fixture influence the production and living of people because extinguishing suddenly is prevented effectively from, and cost is low.
Description
Technical field
The utility model is related to the technical field of power supply, and circuit is controlled more specifically to a kind of power supply overheat protector
And power supply.
Background technology
Compared with traditional lighting such as incandescent lamp, fluorescent lamp, LED illumination is because with obvious energy-conservation, efficient, environmental protection, life-span
It is longer, obtained increasingly being widely applied the features such as colour rendering is more preferable, because LED illumination System has complex original
Reason, across optics, the field such as electrically and thermally, therefore, when carrying out large-scale application, usually occurs that power source life is short and can
The problems such as by property deficiency, causing the advantage of LED illumination can not fully show, so the key of LED illumination large-scale promotion application
It is that the high reliability of driving power supply.LED drive power is the core of LED illumination lamp, and its life-span directly affects LED illumination
The life-span of light fixture.And it is exactly temperature to influence the key of power source life, therefore, overheat protector function is added in LED drive power
Power supply and light fixture can effectively be protected.Current large power supply much has thermal-shutdown circuit, uses more protection circuit
It is that this protected mode is when temperature is too high, and power supply can be stopped at once based on temperature switch design, causes LED to be dashed forward
So extinguish, influence the production and living of people, and cost is high.
Utility model content
The technical problems to be solved in the utility model is that the above-mentioned existing design for prior art works as power source temperature mistake
Power supply can be stopped at once when high causes LED to be extinguished suddenly, influences the production and living of people, and the high defect of cost, carries
Circuit and power supply are controlled for a kind of power supply overheat protector.
The utility model solves the technical scheme that its technical problem used：Construct a kind of power supply overheat protector control electricity
Road, including：
The vice-side winding of transformer；
It is connected with the vice-side winding of the transformer, receives the secondary voltage of the vice-side winding output and export electricity
The current rectifying and wave filtering circuit of pressure；
It is connected between the current rectifying and wave filtering circuit and the negative terminal of power output end, the output voltage is sampled simultaneously
Export the sample circuit of sampled voltage；
The arithmetic control circuit being connected with the sample circuit, the arithmetic control circuit produces reference voltage；
It is connected with the arithmetic control circuit, the bleeder circuit of voltage division signal is exported based on the reference voltage；
The temperature detection control circuit being connected with the bleeder circuit；
The temperature detection control circuit detects the temperature of the power supply and adjusts the partial pressure in the power supply excess temperature
The voltage division signal of circuit output, the arithmetic control circuit is compared output feedback with the sampled voltage according to the voltage division signal
Control signal is to reduce the output current of the power supply.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the arithmetic control circuit includes control
Coremaking piece, the control chip includes the first operational amplifier and the second operational amplifier；
The in-phase input end of first operational amplifier is the reference voltage controlling switch of the control chip, described the
The inverting input of two operational amplifiers is the signal acquisition pin of the control chip.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the sample circuit includes sampling electricity
RJ1 is hindered, the first end of the sampling resistor RJ1 is connected to reference ground, and the second end of the sampling resistor RJ1 and the power supply are defeated
Go out the negative terminal connection at end.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the bleeder circuit includes resistance R71
With resistance R1；The first end of the resistance R71 is connected with the reference voltage controlling switch of the control chip, the resistance R71
The second end be connected with the first end of the resistance R1, the second end of resistance R1 connection reference ground；The resistance R71 and institute
State the in-phase input end that the node between resistance R1 is additionally coupled to second operational amplifier.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the temperature detection control circuit bag
Include resistance R93, power switch, pull-up resistor RT1 and pull down resistor R90；The first end of the resistance R93 and the control core
The reference voltage controlling switch connection of piece, the second end of the resistance R93 is connected with the second end of the power switch, the work(
The first end of rate switch is connected with the second end of the pull-up resistor RT1, the first end connection power supply of the pull-up resistor RT1
End, the first end of the pull down resistor R90 is connected with the first end of the power switch, the second end of the pull down resistor R90
Reference ground is connected jointly with the 3rd end of the power switch；
In the power supply excess temperature, the resistance reduction of the pull-up resistor RT1 is defeated after the pull-up resistor RT1 partial pressures
Enter to the voltage signal of the power switch to reach the conducting voltage of the power switch, the power switch is turned on and made described
Resistance R93 is shorted to reference ground, and the resistance R93 is in parallel with the bleeder circuit, reduces the partial pressure of the bleeder circuit output
Signal, second operational amplifier is compared output feedback ontrol signal according to the voltage division signal with the sampled voltage, is entered
And reduce the output current of the power supply.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the power switch is triode
Q10, the first end of the power switch is the base stage of the triode Q10, and the second end of the power switch is three pole
Pipe Q10 colelctor electrode, the 3rd end of the power switch is the emitter stage of the triode Q10；
In the power supply excess temperature, the pull-up RT1 resistances reduction, the base voltage of the triode Q10 increases and reached
To conducting voltage, the triode Q10 is switched on, and after triode Q10 conductings, the resistance R93 is shorted to reference ground,
The resistance R93 is in parallel with the bleeder circuit, reduces the voltage division signal of the bleeder circuit output, second operation amplifier
Device is compared output feedback ontrol signal with the sampled voltage according to the voltage division signal, and then reduces the output electricity of the power supply
Stream.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the pull-up resistor RT1 is negative temperature
Coefficient resistance.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that the resistance R93 is adjustable resistance.
Circuit is controlled in power supply overheat protector described in the utility model, it is preferable that also including resistance R70, the resistance
R70 is connected between the arithmetic control circuit and the temperature detection control circuit.
The utility model also provides a kind of power supply, including above-mentioned power supply overheat protector control circuit.
Implement power supply overheat protector control circuit of the present utility model and power supply, have the advantages that：The protection control
Circuit processed includes the vice-side winding of transformer；It is connected with the vice-side winding of the transformer, receives the vice-side winding output
Secondary voltage and the current rectifying and wave filtering circuit for exporting output voltage；It is connected to the negative terminal of the current rectifying and wave filtering circuit and power output end
Between, the sample circuit of sampled voltage is sampled and exported to the output voltage；The computing being connected with the sample circuit
Circuit is controlled, the arithmetic control circuit produces reference voltage；It is connected with the arithmetic control circuit, based on the reference voltage
Export the bleeder circuit of voltage division signal；The temperature detection control circuit being connected with the bleeder circuit；The temperature detection control
The temperature of power supply described in electric circuit inspection and the voltage division signal that the bleeder circuit output is adjusted in the power supply excess temperature, the fortune
Calculate control circuit and output feedback ontrol signal is compared with the sampled voltage according to the voltage division signal, to reduce the power supply
Output current.This programme is by increasing temperature detection control circuit power supply occurring on the original circuit base of power supply
During the abnormal conditions of temperature, the output current of power supply is reduced, realizes the reduction to output power of power supply to reduce power supply and bear
The temperature of load, is prevented effectively from the problem of device failure and light fixture influence the production and living of people because extinguishing suddenly, and decompression electricity
Component used in road is all very stable, can significantly reduce the material cost of power supply.
Brief description of the drawings
Below in conjunction with drawings and Examples, the utility model is described in further detail, in accompanying drawing：
Fig. 1 is the logic diagram that the utility model power supply overheat protector control circuit first is implemented；
Fig. 2 is the circuit theory diagrams that the utility model power supply overheat protector controls circuit first embodiment.
Embodiment
In order that the purpose of this utility model, technical scheme and advantage are more clearly understood, below in conjunction with accompanying drawing and implementation
Example, the utility model is further elaborated.
The problem of existing for prior art, circuit is controlled the utility model proposes a kind of power supply overheat protector.This reality
Can be applied to LED field with new proposed power supply overheat protector control circuit, such as can as LED power overheat protector control
Circuit processed, is loaded as the various light fixtures of LED, such as LED mine lamp, the light fixture such as LED street lamp.The power supply overheat protector control circuit by
Temperature detection control circuit is added in the control loop of power output end, for detecting the temperature of power supply and being adjusted in power supply excess temperature
The voltage division signal of the bleeder circuit output in control loop is saved, and then adjusts the voltage letter of the second operational amplifier in-phase input end
Number, then be compared the voltage signal of in-phase input end and its inverting input by the second operational amplifier, by comparing again
Output feedback ontrol signal is to feedback circuit after amplification, by the control circuit (feedback of feedback circuit output feedback signal to primary side
Circuit and the control circuit of primary side are not shown in figure), the signal of primary side is adjusted by primary-side-control circuit, and then reach reduction electricity
The output current in source, realizes reduction power, and reduces the purpose of power source temperature, so as to efficiently avoid device because of temperature
Spend high and damage, extend the service life of power supply, and solve makes lamp dash forward because the too high power supply of temperature is stopped immediately
The problem of so extinguishing the production and life of influence people.
As depicted in figs. 1 and 2, in the logic diagram that the utility model power supply overheat protector controls circuit first to implement,
The vice-side winding N1 of power supply overheat protector control circuit including transformer T1, be connected with transformer T1 vice-side winding N1 it is whole
Stream filter circuit 10, the sample circuit 20 being connected between current rectifying and wave filtering circuit 10 and the negative terminal of power output end and sampling electricity
Arithmetic control circuit 30 that road 20 is connected, the bleeder circuit 40 that is connected with arithmetic control circuit 30 and it is connected with bleeder circuit
Temperature detection control circuit 50.
Secondary voltage and output electricity that the vice-side winding N1 that current rectifying and wave filtering circuit 10 is used for receiving transformer T1 is exported
Pressure.Sample circuit 20 is used to sampling to output voltage and exporting sampled voltage.Arithmetic control circuit 30 has been internally integrated ginseng
Reference voltage is examined, reference voltage can be provided to bleeder circuit 30.The benchmark that bleeder circuit 40 is proposed according to arithmetic control circuit 30
Voltage generates voltage division signal.Temperature detection control circuit is used to detect the temperature of power supply and adjusts partial pressure when excess temperature occurs in power supply
The voltage division signal of circuit output reduces the voltage in voltage division signal；The partial pressure that arithmetic control circuit 30 is then lowered according to this is believed
Number it is compared with sampled voltage, and feeds back to according to comparative result output feedback ontrol signal the primary-side-control electricity of power supply
Road (not shown), and then reduce the output current of power supply.
Further, power supply overheat protector control circuit of the present utility model also includes resistance R70, the resistance R70 strings
It is associated between arithmetic control circuit 20 and temperature detection control circuit 50.It is to be appreciated that in certain embodiments, resistance R70
Reference voltage for being exported to arithmetic control circuit 30 carries out partial pressure.
Specifically, transformer T1 vice-side winding N1 produces corresponding induction electric based on the source voltage that primary side winding is exported
Gesture, and export secondary voltage.It is to be appreciated that the secondary voltage of vice-side winding N1 outputs is square-wave voltage.Preferably, secondary
Winding N1 output secondary voltage as power supply voltage, in embodiment of the present utility model, vice-side winding N1 output pair
Polygonal voltage rectified filter circuit 10 exported after rectifying and wave-filtering the output voltage of DC voltage, i.e. power supply.Further, it is defeated
Go out voltage as the supply voltage powering load of load.
As shown in Fig. 2 current rectifying and wave filtering circuit 10 includes commutation diode D7 and filter capacitor CE5.Commutation diode D7's
Anode is connected with vice-side winding N1 anode, and commutation diode D7 negative electrode is connected with filter capacitor CE5 positive pole, and both are even
The node connect is additionally coupled to the anode of load；Vice-side winding N1 negative terminal is connected to filter capacitor CE5 negative pole, and both connections
Node be additionally coupled to reference ground.Preferably, the alternating voltage progress that commutation diode D7 is used to export vice-side winding N1 is whole
Stream, exports d. c. voltage signal, i.e., alternating voltage is converted into DC voltage by commutation diode D7 and used for load.Filtering
Electric capacity CE5 to being filtered by the commutation diode D7 d. c. voltage signals exported, by the noise in d. c. voltage signal and
Interference component is filtered out, so that being supplied to the output voltage of load more smoothly, stably.
Current rectifying and wave filtering circuit 10 also includes dummy resistance R14, and dummy load circuit R14 is in parallel with filter capacitor CE5.At this
In embodiment, dummy resistance R14 is used to prevent power supply from occurring shaking and discontinuous operation in unloaded or underloading, reduces output electricity
Press through punching.
Sample circuit 20 includes sampling resistor RJ1, and sampling resistor RJ1 first end is connected with current rectifying and wave filtering circuit 10, i.e.,
Sampling resistor RJ1 first end is connected reference ground, sampling resistor RJ1 the second end and electricity jointly with filter capacitor CE5 negative pole
The negative terminal connection of source output terminal, sampling resistor RJ1 the second end is additionally coupled to arithmetic control circuit 30.It is to be appreciated that sampling
Resistance RJ1 is used for the output current for gathering power output end, and exports corresponding sampled voltage.
Arithmetic control circuit 30 is used for according to output to the output reference voltage of bleeder circuit 40, while always according to bleeder circuit
The voltage division signal of 30 outputs is compared output feedback ontrol signal with sampled voltage and feeds back to transformer T1 primary side, so as to reach
To the purpose of regulation power supply output current.Specifically, arithmetic control circuit 30 includes control chip.It is to be appreciated that computing control
Circuit 30 processed also includes the associated peripheral circuits used cooperatively with control chip (associated peripheral circuits are not shown in figure).It is preferred that
Ground, control chip includes the first operational amplifier and the second operational amplifier.Further, the first operational amplifier is same mutually defeated
Enter PIN3 pin of the end for the reference voltage controlling switch, i.e. control chip of control chip.Second operational amplifier it is anti-phase defeated
Enter PIN6 pin of the end for the signal acquisition pin, i.e. control chip of control chip.The in-phase input end of second operational amplifier
For the input pin of control chip, i.e. control chip PIN5 pins be arithmetic control circuit 30 the second operational amplifier input
End.Specifically, the negative terminal connection of the PIN6 pins of control chip and power output end, for receiving adopting on sampling resistor RJ1
Sample voltage, the sampled voltage that control chip is received according to PIN6 pins, while controlling reference voltage controlling switch, (i.e. PIN3 draws
Pin) output reference voltage signal, to resistance R70, exports to bleeder circuit 40 after resistance R70 partial pressures, exported by bleeder circuit 40
Voltage division signal is back to the signal input pin (i.e. PIN5 pins) of control chip.Specifically, the same phase of the first operational amplifier
Input (PIN3 pins) is connected with resistance R70 first end, and the output end (PIN1 pins) of the first operational amplifier is connected to
(feedback signal is back to transformer T1 primary side winding to feedback circuit by the feedback circuit, specific feedback electricity not shown in figure
Road).The inverting input (PIN6 pins) of second operational amplifier is connected with sampling resistor RJ1 the second end, and the second computing is put
The node of in-phase input end (PIN5 pins) between resistance R71 and resistance R1 of big device is connected, the second operational amplifier it is defeated
Go out end to be connected to feedback circuit (feedback signal is back to transformer T1 primary side winding by the feedback circuit, not shown in figure has
The feedback circuit of body).
Preferably, in embodiment of the present utility model, the magnitude of voltage of reference voltage is 2.5V, and the output of PIN3 pins
Reference voltage is constant voltage, i.e. 2.5V.It is to be appreciated that the specific magnitude of voltage of reference voltage is determined by control chip, and
It is not limited to the specific magnitude of voltage of the utility model.
Bleeder circuit 40 is used to carry out partial pressure to the reference voltage that arithmetic control circuit 30 is exported and exports voltage division signal, point
Signal output is pressed to the signal input pin (i.e. PIN5 pins) of the second operational amplifier of the control chip in control circuit 30,
The sampled voltage at the sampling resistor RJ1 ends that the voltage inputted by PIN5 pins is inputted with PIN6 pins is compared, after comparing
The amplified output feedback ontrol signal of signal to feedback circuit, the control electricity of transformer T1 primary sides is fed back to by feedback circuit
Road (feedback circuit and primary-side-control circuit not shown in figure), and then realize the output current of regulation power supply.Specifically, partial pressure electricity
Road 40 includes resistance R71 and resistance R1.Resistance R71 first end is connected with resistance R70 the second end, resistance R71 the second end
It is connected with resistance R1 first end, resistance R1 the second end connection reference ground, and resistance R71 the second end and the first of resistance R1
Node between end is additionally coupled to the signal input pin (i.e. PIN5 pins) of the operational amplifier of control chip second.It is appreciated that
Ground, the node voltage between signal the input pin input resistance R71 and resistance R1 of the operational amplifier of control chip second.It is preferred that
Ground, due to the characteristic of the second operational amplifier " empty short ", the PIN5 pin voltages of control chip are identical with the voltage of PIN6 pins.
Therefore, by adjust the voltage of control chip PIN5 pins so that reach regulation control chip PIN6 pins voltage, that is, sample
Resistance RJ1 terminal voltage.
Temperature detection control circuit 50 is used to adjust what bleeder circuit 40 was exported when the abnormal conditions of excess temperature occurs in power supply
Voltage division signal, realizes the purpose of the output current of reduction power supply.It is to be appreciated that when temperature such as occurs in the course of the work in power supply
During too high phenomenon, the power switch conducting of temperature detection control circuit 50, and with the formation parallel circuit of bleeder circuit 40, enter one
The resistance value of step reduction resistance value, i.e. parallel circuit is less than the resistance value of bleeder circuit 40, and then control circuit 30 is exported
When reference voltage carries out partial pressure, the voltage division signal obtained is less than the voltage division signal before temperature detection control circuit 50 is turned on, i.e.,
Reduce the magnitude of voltage of control chip signal input pin (PIN5 pins), reduction sampling resistor RJ1 terminal voltage.Due to sampling electricity
The resistance value for hindering RJ1 keeps constant, when sampling resistor RJ1 terminal voltage reduction, from Ohm's law, flows through sampling resistor
RJ1 electric current changes with voltage change, i.e. the electric current of sampling resistor RJ1 is also reduced.And flow through sampling resistor RJ1 electric current i.e.
For the output current of power output end, that is, reduce the output current of power supply.Because electric power output voltage keeps constant, therefore,
In the case where output current is reduced, power output is also decreased, i.e. the output lower power consumption of power supply, and then realize reduction
The temperature of power supply, makes the caloric value of load also decrease.It is to be appreciated that effectively being protected by the effect of reduction voltage circuit 40
The security performance of load, extends the service life of power supply.
Further, temperature detection control circuit 50 includes resistance R93, power switch, pull-up resistor RT1 and drop-down electricity
Hinder R90.Resistance R93 first end is connected with resistance R70 the second end, resistance R70 first end and the benchmark electricity of control chip
Press controlling switch (PIN3 pins) connection, i.e. the reference voltage controlling switch that resistance R93 passes through resistance R70 and control chip
(PIN3 pins) is connected.Resistance R93 the second end and the second end of power switch are connected, first end and the pull-up electricity of power switch
Hinder RT1 the second end connection, pull-up resistor RT1 first end connection feeder ear, pull down resistor R90 first end and power switch
First end connection, pull down resistor R90 the second end and the 3rd end of power switch connect reference ground jointly.Preferably, power
Switch as triode.As Fig. 2 shows, power switch is triode Q10.The first end of power switch is triode Q10 base stage, work(
The colelctor electrode that second end of rate switch is triode Q10, the 3rd end of power switch is triode Q10 emitter stage.It can manage
Xie Di, the conducting of power switch is controlled with judging the first end control by power switch by triode Q10 base stage,
When the voltage that triode Q10 base stage is received reaches triode Q10 conducting voltage, triode Q10 colelctor electrode and hair
Emitter-base bandgap grading is turned on.It is to be appreciated that triode Q10 conducting voltage is 0.6~0.7V, and before triode Q10 conductings, temperature inspection
Work of the observing and controlling circuit 50 on power circuit does not influence.
In embodiment of the present utility model, it is preferable that pull-up resistor RT1 is thermistor.Further, thermistor
RT1 is the thermistor of negative temperature system.When the temperature increases, thermistor RT1 resistance value is reduced as temperature is raised,
Gradually reduced with thermistor RT1 resistance, thermistor RT1 terminal voltage is gradually reduced, and then cause triode Q10's
Base voltage is gradually risen, when reaching triode Q10 conducting voltage, and triode Q10 colelctor electrode and emitter stage are turned on, this
When, resistance R93 is shorted to reference ground, i.e. resistance R93 the second end connection reference ground, and now, resistance R93 and bleeder circuit 40 are simultaneously
Connection.After triode Q10 conductings, the voltage division signal that the reduction bleeder circuit 40 of temperature detection control circuit 50 is exported reduces
Node voltage between resistance R71 and resistance R1, and then the voltage of PIN5 pins is dragged down, by " empty short " of the second operational amplifier
Characteristic, PIN6 pin voltages are identical with the voltage of PIN5 pins.In other words, the voltage of PIN6 pins is pulled low, and causes sampling
Resistance RJ1 terminal voltage reduction, and then output current is reduced, in the case where output voltage is constant, reach reduction output work
The purpose of rate, realizes the temperature of reduction power supply.
In embodiment of the present utility model, it is preferable that resistance R93 is adjustable resistance.Further, as triode Q10
After conducting, the power output in the case of power supply excess temperature can be changed by adjusting resistance R93 resistance.Specifically, resistance is worked as
During R93 resistance increase, the parallel resistance after resistance R93 is in parallel with resistance R71, resistance R1 increases therewith, now, parallel circuit
The voltage increase got；Conversely, when resistance R93 resistance reduce when, it is after resistance R93 is in parallel with resistance R71, resistance R1 and
Connection resistance reduces therewith, and the voltage that now parallel circuit is got reduces.Now the second operational amplifier of control chip is same
Phase pin (PIN5 pins) input resistance R71 and resistance R1 between node voltage also with resistance R93 resistance change and
Change, i.e., when resistance R93 resistance increases, the voltage of PIN5 pins is relative to be increased, and output current increase, power output also increases
Greatly；When resistance R93 resistance reduces, the voltage of PIN5 pins is relatively reduced, and output current reduces, and power output also reduces.Cause
This, when excess temperature occurs in power supply, triode Q10 conductings, by adjusting resistance R93 resistance, gradually reduce the of control chip
The voltage of two operational amplifier input pins (PIN5 pins), and then gradually reduction sampling resistor RJ1 terminal voltage, so as to realize
The purpose of output current is gradually reduced, i.e., gradually reduces power output, solves because excess temperature power supply is stopped power supply at once, load
It is stopped immediately, when connecing LED such as load, LED gives people because power supply overtemperature protection is stopped power supply immediately and is extinguished suddenly
Production and life the problem of make troubles.Simultaneously can also effectively prevent because temperature is too high damage component the problem of, prolong
The service life of power supply is grown.In addition, component used in the increased reduction voltage circuit 40 of the utility model is all very cheap, therefore
Significantly reduce the material cost of power supply.
The operation principle to Fig. 2 circuits is further detailed below：
When the temperature rise of power supply, with the rising of power source temperature, thermistor RT1 resistance is gradually reduced, three poles
Pipe Q10 base voltage gradually increases, and causes the leakage current between triode Q10 colelctor electrode and emitter stage to incrementally increase.When
When base voltage reaches triode Q10 cut-in voltage, triode Q10 conductings, so that resistance R93 is turned on over the ground, and now, electricity
Hinder R93 in parallel with bleeder circuit 30；That is resistance R71 is in parallel with resistance R93 again after being connected with resistance R1, thus, resistance R93 and electricity
Hinder after R71, resistance R1 parallel connection, parallel resistance is less than the series resistance that resistance R71 connects with resistance R1, and now, the second computing is put
The in-phase input end of big device, i.e. node voltage between the resistance R71 and resistance R1 of the input of PIN5 pins reduce, i.e. PIN5 pins
Voltage be pulled low, the homophase input terminal voltage and the voltage of inverting input that this is lowered by the second operational amplifier again are (i.e.
The sampled voltage of sampling resistor RJ1 collections) it is compared, output feedback ontrol signal (is schemed to feedback circuit after comparing amplification
Not shown in), then dutycycle is controlled by the primary-side-control circuit (not shown) of feedback circuit output feedback signal to power supply
(or working frequency), and then the output current of power output end is reduced, so as to reach reduction output power of power supply, reduce power consumption
Purpose.
The utility model additionally provides a kind of power supply, and the power supply includes above-mentioned overheat protector and controls circuit, by setting
Temperature protection control circuit allows power supply to be effectively protected, it is to avoid damages power supply because temperature is too high, makes the life of people
Produce work unaffected, and circuit structure is simple, the cost of material is low.
Above example is only to illustrate technical concepts and features of the present utility model, and its object is to allow be familiar with technique
Personage can understand content of the present utility model and implement accordingly, protection domain of the present utility model can not be limited.It is all with
The equivalent changes and modifications that the utility model right is done, all should belong to the utility model claim covers model
Enclose.
It should be appreciated that for those of ordinary skills, can according to the above description be improved or converted,
And all these modifications and variations should all belong to the protection domain of the utility model appended claims.
Claims (10)
1. a kind of power supply overheat protector controls circuit, it is characterised in that including：
The vice-side winding of transformer；
It is connected with the vice-side winding of the transformer, receives the secondary voltage of the vice-side winding output and export output voltage
Current rectifying and wave filtering circuit；
It is connected between the current rectifying and wave filtering circuit and the negative terminal of power output end, the output voltage is sampled and exported
The sample circuit of sampled voltage；
The arithmetic control circuit being connected with the sample circuit, the arithmetic control circuit produces reference voltage；
It is connected with the arithmetic control circuit, the bleeder circuit of voltage division signal is exported based on the reference voltage；
The temperature detection control circuit being connected with the bleeder circuit；
The temperature detection control circuit detects the temperature of the power supply and adjusts the bleeder circuit in the power supply excess temperature
The voltage division signal of output, the arithmetic control circuit is compared output feedback ontrol according to the voltage division signal with the sampled voltage
Signal is to reduce the output current of the power supply.
2. power supply overheat protector according to claim 1 controls circuit, it is characterised in that the arithmetic control circuit includes
Control chip, the control chip includes the first operational amplifier and the second operational amplifier；
The in-phase input end of first operational amplifier is the reference voltage controlling switch of the control chip, second fortune
The inverting input for calculating amplifier is the signal acquisition pin of the control chip.
3. power supply overheat protector according to claim 2 controls circuit, it is characterised in that the sample circuit includes sampling
Resistance RJ1, the sampling resistor RJ1 first end are connected to reference ground, the second end and the power supply of the sampling resistor RJ1
The negative terminal connection of output end.
4. power supply overheat protector according to claim 2 controls circuit, it is characterised in that the bleeder circuit includes resistance
R71 and resistance R1；The first end of the resistance R71 is connected with the reference voltage controlling switch of the control chip, the resistance
R71 the second end is connected with the first end of the resistance R1, the second end connection reference ground of the resistance R1；The resistance R71
Node between the resistance R1 is additionally coupled to the in-phase input end of second operational amplifier.
5. power supply overheat protector according to claim 2 controls circuit, it is characterised in that the temperature detection control circuit
Including resistance R93, power switch, pull-up resistor RT1 and pull down resistor R90；
The first end of the resistance R93 is connected with the reference voltage controlling switch of the control chip, and the second of the resistance R93
End is connected with the second end of the power switch, and the first end of the power switch and the second end of the pull-up resistor RT1 connect
Connect, the first end connection feeder ear of the pull-up resistor RT1, first end and the power switch of the pull down resistor R90
First end is connected, and the second end of the pull down resistor R90 is connected reference ground jointly with the 3rd end of the power switch；
In the power supply excess temperature, the reduction of the resistance of the pull-up resistor RT1, inputted after the pull-up resistor RT1 partial pressures to
The voltage signal of the power switch reaches the conducting voltage of the power switch, and the power switch turns on and makes the resistance
R93 is shorted to reference ground, and the resistance R93 is in parallel with the bleeder circuit, reduces the voltage division signal of the bleeder circuit output,
Second operational amplifier is compared output feedback ontrol signal with the sampled voltage according to the voltage division signal, and then is reduced
The output current of the power supply.
6. power supply overheat protector according to claim 5 controls circuit, it is characterised in that the power switch is triode
Q10, the first end of the power switch is the base stage of the triode Q10, and the second end of the power switch is three pole
Pipe Q10 colelctor electrode, the 3rd end of the power switch is the emitter stage of the triode Q10；
In the power supply excess temperature, the resistance reduction of the pull-up resistor RT1, the base voltage increase of the triode Q10 is simultaneously
Conducting voltage is reached, the triode Q10 is switched on, after triode Q10 conductings, the resistance R93 is shorted to reference
Ground, the resistance R93 is in parallel with the bleeder circuit, reduces the voltage division signal of the bleeder circuit output, second computing
Amplifier is compared output feedback ontrol signal with the sampled voltage according to the voltage division signal, and then reduces the defeated of the power supply
Go out electric current.
7. power supply overheat protector according to claim 5 controls circuit, it is characterised in that the pull-up resistor RT1 is negative
Temperature coefficient thermistor.
8. power supply overheat protector according to claim 5 controls circuit, it is characterised in that the resistance R93 is adjustable electric
Resistance.
9. the power supply overheat protector control circuit according to any one of claim 1 to 8, it is characterised in that also including resistance
R70, the resistance R70 is connected between the arithmetic control circuit and the temperature detection control circuit.
10. a kind of power supply, it is characterised in that control electricity including the power supply overheat protector as described in any one of claim 1 to 9
Road.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621444411.0U CN206533294U (en) | 2016-12-27 | 2016-12-27 | Power supply overheat protector controls circuit and power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621444411.0U CN206533294U (en) | 2016-12-27 | 2016-12-27 | Power supply overheat protector controls circuit and power supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206533294U true CN206533294U (en) | 2017-09-29 |
Family
ID=59921822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621444411.0U Active CN206533294U (en) | 2016-12-27 | 2016-12-27 | Power supply overheat protector controls circuit and power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206533294U (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109738834A (en) * | 2019-01-31 | 2019-05-10 | 苏州经贸职业技术学院 | A kind of detection device of server power supply |
| CN110635696A (en) * | 2018-06-25 | 2019-12-31 | 台达电子工业股份有限公司 | Power supply switching circuit and switching method |
| CN110943428A (en) * | 2019-12-20 | 2020-03-31 | 上海新进芯微电子有限公司 | Over-temperature protection circuit and electronic product |
| WO2020098201A1 (en) * | 2018-11-14 | 2020-05-22 | 深圳市崧盛电子股份有限公司 | Over-temperature protection circuit of led driving power supply |
| CN112737297A (en) * | 2020-12-15 | 2021-04-30 | 广东新昇电业科技股份有限公司 | Driving power supply and method for improving reliability of driving power supply in abnormal environment |
| CN114025413A (en) * | 2017-12-19 | 2022-02-08 | 海能达通信股份有限公司 | Temperature protection circuit and electronic equipment |
| CN117111520A (en) * | 2023-09-12 | 2023-11-24 | 中航试金石检测科技(大厂)有限公司 | Laboratory environment monitoring system |
-
2016
- 2016-12-27 CN CN201621444411.0U patent/CN206533294U/en active Active
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114025413A (en) * | 2017-12-19 | 2022-02-08 | 海能达通信股份有限公司 | Temperature protection circuit and electronic equipment |
| CN114025413B (en) * | 2017-12-19 | 2023-12-19 | 海能达通信股份有限公司 | Temperature protection circuit and electronic equipment |
| CN110635696A (en) * | 2018-06-25 | 2019-12-31 | 台达电子工业股份有限公司 | Power supply switching circuit and switching method |
| WO2020098201A1 (en) * | 2018-11-14 | 2020-05-22 | 深圳市崧盛电子股份有限公司 | Over-temperature protection circuit of led driving power supply |
| CN109738834A (en) * | 2019-01-31 | 2019-05-10 | 苏州经贸职业技术学院 | A kind of detection device of server power supply |
| CN110943428A (en) * | 2019-12-20 | 2020-03-31 | 上海新进芯微电子有限公司 | Over-temperature protection circuit and electronic product |
| CN112737297A (en) * | 2020-12-15 | 2021-04-30 | 广东新昇电业科技股份有限公司 | Driving power supply and method for improving reliability of driving power supply in abnormal environment |
| CN117111520A (en) * | 2023-09-12 | 2023-11-24 | 中航试金石检测科技(大厂)有限公司 | Laboratory environment monitoring system |
| CN117111520B (en) * | 2023-09-12 | 2024-02-20 | 中航试金石检测科技(大厂)有限公司 | Laboratory environment monitoring system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN206533294U (en) | Power supply overheat protector controls circuit and power supply | |
| CN106793246A (en) | Leadage circuit and its control method and LED control circuit | |
| CN107454706B (en) | A kind of integrated circuit and linear constant current driving circuit and its control method | |
| CN208477417U (en) | A kind of LDO flow restriction not increasing quiescent current | |
| CN203618179U (en) | Voltage-stabilization dimmable LED (light emitting diode) driving power supply circuit | |
| CN105517268A (en) | Bus current control circuit, current-constant driving controller and LED light source | |
| CN103533707A (en) | Voltage-stabilization dimmable LED (light emitting diode) driving power supply circuit | |
| CN106658838A (en) | Lighting device, control chip, linear dimming system and linear dimming method | |
| CN107171555A (en) | A kind of mu balanced circuit applied to high tension voltage IC interior | |
| CN107148121A (en) | A kind of chop control linear switch constant current and constant power circuit | |
| CN102404921B (en) | Output current adjustable intelligent constant current power supply device | |
| CN104754800B (en) | A kind of control device of LED modules inrush current | |
| CN107591282A (en) | The control device and method of relay coil | |
| CN106849629A (en) | A kind of protection circuit and LED drive circuit | |
| CN207965722U (en) | The control circuit of PFC busbar voltages | |
| CN203387165U (en) | High-speed half-bridge MOSFET short circuit protection circuit | |
| CN104080228A (en) | Detection control circuit of electric parameter of lamp | |
| CN108811257A (en) | A kind of control method of LED illumination System and LED load circuit | |
| CN209390429U (en) | LED lamp firm power circuit | |
| CN203708589U (en) | Linear constant current LED driving circuit possessing temperature compensation | |
| CN107969054A (en) | LED drive power, the control method of electric power output voltage and LED lamp | |
| CN207053387U (en) | The power module of automobile controller | |
| CN206442103U (en) | A kind of inexpensive high-definition digital sound equipment multichannel short-circuit protection circuit | |
| CN203327330U (en) | Mobile phone LCD backlight energy-saving drive circuit | |
| CN208657135U (en) | A kind of LED illumination System |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |