CN108495418A - A kind of thermal management algorithm and device of LED - Google Patents
A kind of thermal management algorithm and device of LED Download PDFInfo
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- CN108495418A CN108495418A CN201810377919.0A CN201810377919A CN108495418A CN 108495418 A CN108495418 A CN 108495418A CN 201810377919 A CN201810377919 A CN 201810377919A CN 108495418 A CN108495418 A CN 108495418A
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
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Abstract
The invention discloses the thermal management algorithm of LED a kind of and devices, including：Detect the operating temperature of LED；Corresponding with operating temperature pwm signal is determined according to preset temperature duty ratio correspondence, wherein the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；The driving current for generating LED is corresponded to drive LED operation in safe temperature range according to pwm signal.Wherein, as the rising of LED operation temperature, the duty ratio of corresponding pwm signal reduce, the driving current of generation reduces, and the operating power of LED reduces, to reduce the operating temperature of LED.As it can be seen that the operating temperature that the application can automatically control LED makes it be operated in safe temperature range, the loss late of light output is reduced, maintains the self performance of material as far as possible, to extend the lumen depreciation of LED, and has modified the color temperature shift of LED.
Description
Technical field
The present invention relates to thermal management technology fields, more particularly to the thermal management algorithm and device of a kind of LED.
Background technology
Currently, since LED (Light Emitting Diode, light emitting diode) has brightness high, environmental protection and energy saving etc.
Advantage makes LED lighting technology be widely used in every field.But with the long-time of LED use, the operating temperature of itself compared with
Height can cause light output slowly to be lost and the degradation of material, to influence the lumen depreciation and color temperature shift of LED.It is existing
Have in technology, generally use fan cooling or use highly heat-conductive material improve heat dissipation performance, and still, both thermal management algorithms are only
The lumen depreciation of LED can be extended, with the increase of use time, the performance of LED materials can still be deteriorated, thus can not repair
The color temperature shift of positive LED.
Therefore, how to provide it is a kind of solve above-mentioned technical problem scheme be that those skilled in the art needs to solve at present
The problem of.
Invention content
The object of the present invention is to provide the thermal management algorithm of LED a kind of and devices, can automatically control the operating temperature of LED
So that it is operated in safe temperature range, reduces the loss late of light output, maintain the self performance of material as far as possible, to prolong
The lumen depreciation of LED has been grown, and has had modified the color temperature shift of LED.
In order to solve the above technical problems, the present invention provides a kind of thermal management algorithms of LED, including：
Detect the operating temperature of Light-emitting diode LED；
Pulse width modulation (PWM) letter corresponding with the operating temperature is determined according to preset temperature duty ratio correspondence
Number, wherein the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
The driving current for generating the LED is corresponded to drive the LED operation in safe temperature model according to the pwm signal
It encloses.
Preferably, the setting up procedure of the temperature duty ratio correspondence is specially：
The corresponding beginning work of maximum working temperature, lower working temperature and the lower working temperature of the LED is set
The duty ratio of pwm signal when making, and N number of intermediate work is set between the maximum working temperature and the lower working temperature
Temperature, wherein N is positive integer；
The duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein higher operating temperature corresponds to
Duty ratio be less than the corresponding duty ratio of lower operating temperature；
It is then described that pwm signal corresponding with the operating temperature is determined according to preset temperature duty ratio correspondence, according to
The pwm signal corresponds to the driving current for generating the LED to drive the LED operation specific in the process of safe temperature range
For：
When the operating temperature of the LED is equal to any intermediate operating temperature, PWM corresponding with current operating temperature is determined
Signal, and driving current is correspondingly adjusted to adjust the operating temperature of the LED according to the pwm signal；
When the operating temperature of the LED rises to the maximum working temperature, stop generating driving current to control
It states LED to be stopped, when the operating temperature of the LED drops to the lower working temperature, when generating with starting to work
The corresponding driving current of pwm signal to drive the LED to start to work.
Preferably, it is determining pwm signal corresponding with current operating temperature, and drive is correspondingly adjusted according to the pwm signal
Before streaming current, which further includes：
When the operating temperature of the LED is equal to any intermediate operating temperature, it is pre- to judge whether current operating temperature is more than
If reliability temperature threshold, pwm signal corresponding with current operating temperature is determined if so, executing, and corresponding according to the pwm signal
Ground adjusts the step of driving current；If it is not, not adjusting driving current then.
Preferably, the operating temperature of the LED is specially equal to the decision process of any intermediate operating temperature：
When the operating temperature of the LED reaches any intermediate operating temperature, and the time arrival of lasting current operating temperature
When preset durations, judge that the operating temperature of the LED is equal to any intermediate operating temperature.
Preferably, the operating temperature of the LED rises to the maximum working temperature or drops to the lower limit work temperature
The decision process of degree is specially：
It is arrived when the time that the operating temperature of the LED reaches the maximum working temperature and the lasting maximum working temperature
Up to the duration, or reach the lower working temperature and continue the lower working temperature time reach it is described lasting
When the time, correspondingly judge that the operating temperature of the LED rises to the maximum working temperature or drops to the lower limit work
Temperature.
Preferably, the process of the adjustment driving current is specially：
Add up algorithm using default high dynamic or default gamma correction algorithm adjusts driving current.
In order to solve the above technical problems, the present invention also provides a kind of heat management devices of LED, including：
Temperature sensing circuit, the operating temperature for detecting LED；
Controller, for determining pwm signal corresponding with the operating temperature according to preset temperature duty ratio correspondence,
Wherein, the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
Driving circuit, for corresponding to the driving current for generating the LED according to the pwm signal to drive the LED works
Make in safe temperature range.
Preferably, the temperature sensing circuit includes power supply, divider resistance and for by the operating temperature of the LED
It is converted into the thermistor of voltage value, wherein：
The output end of the power supply is connect with the first end of the divider resistance, the second end of the divider resistance with
The first end of the thermistor connects, the second end ground connection of the thermistor；
Then the controller includes：
A/D converter for the voltage value to be converted into the operating temperature.
Preferably, the temperature sensing circuit further includes the capacitance for circuit where stablizing, the anode point of the capacitance
It is not connect with the first end of the second end of the divider resistance and the thermistor, the cathode of the capacitance and temperature-sensitive electricity
The second end of resistance connects, common end grounding.
Preferably, the controller includes：
Setting unit, maximum working temperature, lower working temperature and the lower working temperature for the LED to be arranged
The duty ratio of pwm signal when corresponding start-up operation, and set between the maximum working temperature and the lower working temperature
It sets N number of intermediate operating temperature, and the duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein N is just whole
Number, the corresponding duty ratio of higher operating temperature are less than the corresponding duty ratio of lower operating temperature；
Control unit, for when the operating temperature of the LED is equal to any intermediate operating temperature, generating work at present temperature
Spend corresponding pwm signal；When the operating temperature of the LED rises to the ceiling temperature, stop generating pwm signal, until
When the operating temperature of the LED drops to the lower limit temperature, pwm signal when starting to work is generated.
The present invention provides a kind of thermal management algorithms of LED, including：Detect the operating temperature of LED；It is accounted for according to preset temperature
Sky determines corresponding with operating temperature pwm signal than correspondence, wherein the corresponding duty ratio of higher operating temperature less than compared with
The corresponding duty ratio of low operating temperature；The driving current for generating LED is corresponded to drive LED operation in safety according to pwm signal
Temperature range.
Compared with thermal management algorithm in the prior art, the application detects the operating temperature of LED first, then according to setting
Temperature duty ratio correspondence determine corresponding with operating temperature pwm signal, to generate corresponding driving current to drive
LED operation is in safe temperature range.Wherein, with the rising of LED operation temperature, the duty ratio of corresponding pwm signal reduces, raw
At driving current reduce, the operating power of LED reduces, to reduce the operating temperature of LED.As it can be seen that the application can be certainly
The operating temperature of dynamic control LED makes it be operated in safe temperature range, reduces the loss late of light output, maintains material as far as possible
The self performance of material to extend the lumen depreciation of LED, and has modified the color temperature shift of LED.
The present invention also provides a kind of heat management devices of LED, with above-mentioned thermal management algorithm advantageous effect having the same.
Description of the drawings
It to describe the technical solutions in the embodiments of the present invention more clearly, below will be to institute in the prior art and embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the present invention
Example, for those of ordinary skill in the art, without creative efforts, can also obtain according to these attached drawings
Obtain other attached drawings.
Fig. 1 is a kind of flow chart of the thermal management algorithm of LED provided by the invention；
Fig. 2 is a kind of structural schematic diagram of the heat management device of LED provided by the invention；
Fig. 3 (1) is a kind of structural schematic diagram of LED provided by the invention；
Fig. 3 (2) is the structural schematic diagram of driving circuit shown in a kind of Fig. 2 provided by the invention；
Fig. 4 is a kind of structural schematic diagram of Voltage stabilizing module provided by the invention；
Fig. 5 is the structural schematic diagram of temperature sensing circuit shown in a kind of Fig. 2 provided by the invention.
Specific implementation mode
Core of the invention is to provide a kind of thermal management algorithm and device of LED, can automatically control the operating temperature of LED
So that it is operated in safe temperature range, reduces the loss late of light output, maintain the self performance of material as far as possible, to prolong
The lumen depreciation of LED has been grown, and has had modified the color temperature shift of LED.
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is
A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art
The every other embodiment obtained without making creative work, shall fall within the protection scope of the present invention.
Fig. 1 is please referred to, Fig. 1 is a kind of flow chart of the thermal management algorithm of LED provided by the invention.
The thermal management algorithm includes：
Step S1：Detect the operating temperature of Light-emitting diode LED；
It should be noted that default in the application sets in advance, it is only necessary to which setting is primary, unless according to reality
Situation needs to change, and otherwise need not reset.
Specifically, it is contemplated that LED temperature when long-time uses is higher, and high temperature can cause the light output of LED slowly to be damaged
It loses, influences the lumen depreciation of LED；The material property of LED itself can also be deteriorated, and influence the color temperature shift of LED.So this Shen
It please improve the lumen depreciation and color temperature shift of LED by the way of controlling temperature.
The application detects the operating temperature of LED first, and there are many kinds of the modes of temperature detection, for example, using temperature-sensitive is carried
The circuit of resistance, the voltage value by detecting thermistor determine its temperature value detected.As for the specific side of temperature detection
Formula, the application are not particularly limited herein.
Step S2：Pulse width modulation (PWM) corresponding with operating temperature is determined according to preset temperature duty ratio correspondence
Signal, wherein the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
Specifically, the operating temperature of LED is determined by its operating power, when the internal structure of LED is fixed, the work of LED
Power is by driving the driving current of the driving circuit of its work to determine, and the driving current of LED is by the PWM of input driving circuit
(Pulse Width Modulation, pulse width modulation) signal deciding.
So the correspondence of the operating temperature of LED and the duty ratio of pwm signal is arranged in the application in advance, moreover, it is contemplated that
Duty ratio to pwm signal is smaller, and the driving current of driving circuit is smaller, and the operating power of LED is smaller, and the temperature of LED is lower,
So when the temperature of LED increases, the duty ratio of pwm signal should reduce to reduce the temperature of LED, to realize the control of temperature
System.That is, in temperature duty ratio correspondence, the operating temperature of LED is higher, and the duty ratio of corresponding pwm signal is got over
It is small.
After LED operation, the operating temperature of LED can be detected, then accounted for from temperature according to the operating temperature of detection
Sky lays the first stone than determining duty ratio corresponding with the operating temperature in correspondence for subsequent drive circuit drives LED operation.
Step S3：The driving current for generating LED is corresponded to drive LED operation in safe temperature range according to pwm signal.
Specifically, when the operating temperature of LED increases, the corresponding duty of operating temperature after raising is smaller, in determination
After the corresponding duty ratio of operating temperature after raising, driving circuit, which can correspond to, generates smaller driving current, makes the work of LED
The rate of doing work reduces to reduce the operating temperature of LED, to make LED operation in safe temperature range.As it can be seen that the application can be automatic
The operating temperature of control LED makes it be operated in safe temperature range, reduces the loss late of light output, extends the lumen of LED
Sustainment rate；And the self performance of material is maintained as much as possible, have modified the color temperature shift of LED.
The present invention provides a kind of thermal management algorithms of LED, including：Detect the operating temperature of LED；It is accounted for according to preset temperature
Sky determines corresponding with operating temperature pwm signal than correspondence, wherein the corresponding duty ratio of higher operating temperature less than compared with
The corresponding duty ratio of low operating temperature；The driving current for generating LED is corresponded to drive LED operation in safety according to pwm signal
Temperature range.
Compared with thermal management algorithm in the prior art, the application detects the operating temperature of LED first, then according to setting
Temperature duty ratio correspondence determine corresponding with operating temperature pwm signal, to generate corresponding driving current to drive
LED operation is in safe temperature range.Wherein, with the rising of LED operation temperature, the duty ratio of corresponding pwm signal reduces, raw
At driving current reduce, the operating power of LED reduces, to reduce the operating temperature of LED.As it can be seen that the application can be certainly
The operating temperature of dynamic control LED makes it be operated in safe temperature range, reduces the loss late of light output, maintains material as far as possible
The self performance of material to extend the lumen depreciation of LED, and has modified the color temperature shift of LED.
On the basis of the above embodiments：
As a kind of preferred embodiment, the setting up procedure of temperature duty ratio correspondence is specially：
PWM believes when maximum working temperature, lower working temperature and the lower working temperature corresponding start-up operation of LED is arranged
Number duty ratio, and N number of intermediate operating temperature is set between maximum working temperature and lower working temperature, wherein N is just whole
Number；
The duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein higher operating temperature is corresponding to be accounted for
Sky is than duty ratio corresponding less than lower operating temperature；
Pwm signal corresponding with operating temperature is then determined according to preset temperature duty ratio correspondence, according to pwm signal pair
The driving current of LED should be generated to drive the LED operation to be specially in the process of safe temperature range：
When the operating temperature of LED is equal to any intermediate operating temperature, PWM letters corresponding with current operating temperature are determined
Number, and driving current is correspondingly adjusted to adjust the operating temperature of LED according to the pwm signal；
When the operating temperature of LED rises to maximum working temperature, stop generating driving current to control LED stopping works
Make, when the operating temperature of LED drops to lower working temperature, generates driving corresponding with pwm signal when starting to work
Electric current is to drive LED to start to work.
Further, it is contemplated that LED is in the case where working long hours, even if adjusting its operating temperature always, the work temperature of LED
Degree may also continue rise, only uphill process some slowly, the operating temperature of LED rises to safe temperature range in order to prevent
Outside, the maximum working temperature and lower working temperature of LED is arranged when temperature duty ratio correspondence is arranged in the application first,
The mark temperature that maximum working temperature is stopped as LED, after lower working temperature is stopped as LED due to high temperature,
The mark temperature for waiting for it to start to work.So pwm signal when the application also sets up lower working temperature corresponding start-up operation
Duty ratio.
If maximum working temperature and lower working temperature is only arranged, operating temperature between the two is set as line with duty ratio
Sexual intercourse, then as the operating temperature of LED constantly changes, the duty ratio of pwm signal also can constantly change, and lead to the brightness of LED
Constantly adjustment, the experience effect of user are poor.So the application is arranged one between maximum working temperature and lower working temperature
A or multiple intermediate operating temperatures, and according to the smaller principle of the corresponding duty of higher operating temperature, intermediate work is set
The duty ratio of the corresponding pwm signal of temperature so that the operating temperature of LED is in two adjacent intermediate temperature changes, LED
Brightness will not adjust, improve the experience effect of user.
Correspondingly, when intermediate operating temperature is set as one, the detailed process of LED operation is driven to include：When the work of LED
When making temperature equal to the intermediate operating temperature, pwm signal corresponding with the intermediate operating temperature is determined, and corresponding adjustment driving is electric
Stream, so as to adjust the operating temperature of LED.
When intermediate operating temperature is set as multiple, the detailed process of LED operation is driven to include：When the operating temperature of LED
When equal to any intermediate operating temperature, pwm signal corresponding with current operating temperature is determined, and correspondingly adjust driving current,
So as to adjust the operating temperature of LED.
When the operating temperature of LED rises to maximum working temperature, illustrate that the operating temperature of LED arrived set peace
The upper limit of total temperature range, then corresponding duty ratio is 0, i.e., driving circuit stops generating driving current, is stopped to controlling LED
Work, until the operating temperature of LED drops to lower working temperature, the application generates pwm signal when starting to work, makes driving
Circuit, which corresponds to, generates driving current to drive LED to start to work.
As a kind of preferred embodiment, pwm signal corresponding with current operating temperature is being determined, and believe according to the PWM
Before number correspondingly adjusting driving current, which further includes：
When the operating temperature of LED is equal to any intermediate operating temperature, judge whether current operating temperature is more than default peace
Total temperature threshold value determines pwm signal corresponding with current operating temperature if so, executing, and is correspondingly adjusted according to the pwm signal
The step of whole driving current；If it is not, not adjusting driving current then.
Further, it is contemplated that the operating temperature of LED is before the temperature for not up to influencing light output and own material, nothing
Operating temperature need to be adjusted, so, a reliability temperature threshold is arranged in the application, when the operating temperature of LED is more than the peace
When total temperature threshold value, just go the size for determining duty ratio according to temperature duty ratio correspondence, and corresponding adjustment driving current with
Adjust operating temperature；When the operating temperature of LED is less than or equal to the reliability temperature threshold, without being adjusted to driving current.
As a kind of preferred embodiment, the operating temperature of LED is specific equal to the decision process of any intermediate operating temperature
For：
It is preset when the time that the operating temperature of LED reaches any intermediate operating temperature, and continues current operating temperature reaches
When the duration, judge that the operating temperature of LED is equal to any intermediate operating temperature.
Further, it is contemplated that the system of control LED operation temperature may be interfered, and the operating temperature of detection is caused to go out
Mistake, so the operating temperature of the application repeated detection LED to be to ensure that data are consistent, namely within certain duration, LED can
Current operating temperature is persistently kept, then judges that the operating temperature of LED is equal to the operating temperature of current detection.
For example, the decision process for being equal to any intermediate operating temperature for the operating temperature of LED includes：Continue in certain
In time, if LED persistently keeps one of intermediate operating temperature, judge that the operating temperature of LED is equal to centre work temperature
Degree.
As a kind of preferred embodiment, the operating temperature of LED rises to maximum working temperature or drops to lower limit work
The decision process of temperature is specially：
The duration is reached when the time that the operating temperature of LED reaches maximum working temperature and lasting maximum working temperature,
Or when reaching lower working temperature and continuing arrival duration time of lower working temperature, correspondingly judge the work of LED
Temperature rise is to maximum working temperature or drops to lower working temperature.
Specifically, the judgement of maximum working temperature or lower working temperature is equal to for the operating temperature of LED, is please referred to
State the decision process of intermediate operating temperature.
As a kind of preferred embodiment, the process for adjusting driving current is specially：
Add up algorithm using default high dynamic or default gamma correction algorithm adjusts driving current.
Specifically, there is the non-linear and dynamic deferred characteristic of logarithm to the response of brightness due to human eye, so being adjusted in dynamic
During whole brightness, algorithm (including high dynamic accumulation algorithm and high dynamic regressive algorithm) or gamma correction are added up with high dynamic
Algorithm adjusts driving current, keeps the brightness of LED smooth slowly excessive, solves the shake and delay during brightness adjustment, from
And improve the comfort level of human eye brightness perception.
Fig. 2 is please referred to, Fig. 2 is a kind of structural schematic diagram of the heat management device of LED provided by the invention.
The heat management device includes：
Temperature sensing circuit 1, the operating temperature for detecting LED；
Controller 2, for determining pwm signal corresponding with operating temperature according to preset temperature duty ratio correspondence,
In, the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
Driving circuit 3, for corresponding to the driving current for generating LED according to pwm signal to drive LED operation in safe temperature
Range.
Specifically, Fig. 3 (1) and Fig. 3 (2) is please referred to, Fig. 3 (1) is a kind of structural schematic diagram of LED provided by the invention；
Fig. 3 (2) is the structural schematic diagram of driving circuit shown in a kind of Fig. 2 provided by the invention.LED in the application may include multiple
Concatenated sub- LED, wherein the anode for being located at the sub- LED of head end is connect with the port of the mark of driving circuit 3 LED+, is located at tail end
Cathode and the driving circuit 3 of sub- LED indicate the port of LED- and connect, driving circuit 3 indicates port and the company of controller 2 of IN
It connects, to complete the drive control of LED.As for the specific choice of LED and driving circuit 3, the application does not do special limit herein
It is fixed.
Controller 2 in the application can be but be not limited only to MCU (Micro Control Unit, micro-control unit),
The application is not particularly limited herein.
In addition, controller 2 and driving circuit 3 can be powered by same power module.Further, the heat management device is also
Including Voltage stabilizing module, it is used for the supply voltage of stability controller 2 and driving circuit 3, improves the stability and reliability of device.
Fig. 4 is please referred to, Fig. 4 is a kind of structural schematic diagram of Voltage stabilizing module provided by the invention.
Fig. 5 is please referred to, Fig. 5 is the structural schematic diagram of temperature sensing circuit shown in a kind of Fig. 2 provided by the invention.
As a kind of preferred embodiment, temperature sensing circuit 1 includes power supply, divider resistance R1 and is used for LED
Operating temperature be converted into the thermistor R2 of voltage value, wherein：
The output end of power supply is connect with the first end of divider resistance R1, the second end and thermistor of divider resistance R1
The first end of R2 connects, the second end ground connection of thermistor R2；
Then controller 2 includes：
A/D converter for voltage value to be converted into operating temperature.
Specifically, the temperature sensing circuit in the application includes power supply, divider resistance R1 and thermistor R2.Temperature-sensitive
Resistance R2 is sensitive to temperature change, different resistance values is shown at different temperature, and then change the voltage value at both ends, temperature
Detection circuit will pass through the operating temperature of the voltage value reflection LED of thermistor R2, then controller includes A/D converter, can be incited somebody to action
The voltage value of thermistor R2 is converted into operating temperature, in order to subsequently carry out temperature control zone reason.
Here thermistor R2 can be but be not limited only to NTC (Negative Temperature Coefficient,
Negative temperature coefficient) thermistor, the application is not particularly limited herein.
As a kind of preferred embodiment, temperature sensing circuit 1 further includes the capacitance C, capacitance C for circuit where stablizing
Anode connect respectively with the first end of the second end of divider resistance R1 and thermistor R2, the cathode and thermistor of capacitance C
The second end of R2 connects, common end grounding.
Further, in order to improve the stability of circuit, it is connected in parallel with a capacitor C at the both ends of thermistor R2, makes detection
Operating temperature value it is more accurate.
As a kind of preferred embodiment, controller 2 includes：
Setting unit, maximum working temperature, lower working temperature and lower working temperature for LED to be arranged are corresponding to be opened
The duty ratio of pwm signal when beginning work, and N number of intermediate work temperature is set between maximum working temperature and lower working temperature
Degree, and the duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein N is positive integer, higher operating temperature pair
The duty ratio answered is less than the corresponding duty ratio of lower operating temperature；
Control unit, for when the operating temperature of LED is equal to any intermediate operating temperature, generating current operating temperature pair
The pwm signal answered；When the operating temperature of LED rises to ceiling temperature, stop generating pwm signal, until the operating temperature of LED
When dropping to lower limit temperature, pwm signal when starting to work is generated.
Other introductions for heat management device, please refer to above-mentioned thermal management algorithm embodiment, the application repeats no more.
It should also be noted that, in the present specification, relational terms such as first and second and the like be used merely to by
One entity or operation are distinguished with another entity or operation, without necessarily requiring or implying these entities or operation
Between there are any actual relationship or orders.Moreover, the terms "include", "comprise" or its any other variant meaning
Covering non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only that
A little elements, but also include other elements that are not explicitly listed, or further include for this process, method, article or
The intrinsic element of equipment.In the absence of more restrictions, the element limited by sentence "including a ...", is not arranged
Except there is also other identical elements in the process, method, article or apparatus that includes the element.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
Various modifications to these embodiments will be apparent to those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, of the invention
It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one
The widest range caused.
Claims (10)
1. a kind of thermal management algorithm of LED, which is characterized in that including：
Detect the operating temperature of Light-emitting diode LED；
Pulse width modulation (PWM) signal corresponding with the operating temperature is determined according to preset temperature duty ratio correspondence,
In, the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
The driving current for generating the LED is corresponded to drive the LED operation in safe temperature range according to the pwm signal.
2. the thermal management algorithm of LED as described in claim 1, which is characterized in that the temperature duty ratio correspondence is set
The process of setting is specially：
When the corresponding start-up operation of maximum working temperature, lower working temperature and the lower working temperature of the LED is set
The duty ratio of pwm signal, and N number of intermediate work temperature is set between the maximum working temperature and the lower working temperature
Degree, wherein N is positive integer；
The duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein higher operating temperature is corresponding to be accounted for
Sky is than duty ratio corresponding less than lower operating temperature；
It is then described that pwm signal corresponding with the operating temperature is determined according to preset temperature duty ratio correspondence, according to described
Pwm signal, which corresponds to, generates the driving current of the LED to drive the LED operation to be specially in the process of safe temperature range：
When the operating temperature of the LED is equal to any intermediate operating temperature, PWM letters corresponding with current operating temperature are determined
Number, and driving current is correspondingly adjusted to adjust the operating temperature of the LED according to the pwm signal；
When the operating temperature of the LED rises to the maximum working temperature, stop generating driving current to control the LED
It is stopped, when the operating temperature of the LED drops to the lower working temperature, generates and PWM when starting to work
The corresponding driving current of signal is to drive the LED to start to work.
3. the thermal management algorithm of LED as claimed in claim 2, which is characterized in that corresponding with current operating temperature in determination
Pwm signal, and before correspondingly adjusting driving current according to the pwm signal, which further includes：
When the operating temperature of the LED is equal to any intermediate operating temperature, judge whether current operating temperature is more than default peace
Total temperature threshold value determines pwm signal corresponding with current operating temperature if so, executing, and is correspondingly adjusted according to the pwm signal
The step of whole driving current；If it is not, not adjusting driving current then.
4. the thermal management algorithm of LED as claimed in claim 2, which is characterized in that the operating temperature of the LED be equal to it is any in
Between the decision process of operating temperature be specially：
It is preset when the time that the operating temperature of the LED reaches any intermediate operating temperature, and continues current operating temperature reaches
When the duration, judge that the operating temperature of the LED is equal to any intermediate operating temperature.
5. the thermal management algorithm of LED as claimed in claim 4, which is characterized in that the operating temperature of the LED rises to described
Maximum working temperature or the decision process for dropping to the lower working temperature are specially：
When the operating temperature of the LED reaches the maximum working temperature and continues the time arrival institute of the maximum working temperature
The duration is stated, or reaches the lower working temperature and continues arrival duration time of the lower working temperature
When, correspondingly judge that the operating temperature of the LED rises to the maximum working temperature or drops to the lower working temperature.
6. the thermal management algorithm of LED as claimed in claim 5, which is characterized in that the process of the adjustment driving current is specific
For：
Add up algorithm using default high dynamic or default gamma correction algorithm adjusts driving current.
7. a kind of heat management device of LED, which is characterized in that including：
Temperature sensing circuit, the operating temperature for detecting LED；
Controller, for determining pwm signal corresponding with the operating temperature according to preset temperature duty ratio correspondence,
In, the corresponding duty ratio of higher operating temperature is less than the corresponding duty ratio of lower operating temperature；
Driving circuit, for corresponding to the driving current for generating the LED according to the pwm signal to drive the LED operation to exist
Safe temperature range.
8. the heat management device of LED as claimed in claim 7, which is characterized in that the temperature sensing circuit includes power supply electricity
Source, divider resistance and the thermistor for the operating temperature of the LED to be converted into voltage value, wherein：
The output end of the power supply is connect with the first end of the divider resistance, the second end of the divider resistance with it is described
The first end of thermistor connects, the second end ground connection of the thermistor；
Then the controller includes：
A/D converter for the voltage value to be converted into the operating temperature.
9. the heat management device of LED as claimed in claim 8, which is characterized in that the temperature sensing circuit further includes being used for
The capacitance of circuit where stablizing, the anode of the capacitance respectively with the second end of the divider resistance and the thermistor the
One end connects, and the cathode of the capacitance is connect with the second end of the thermistor, common end grounding.
10. such as the heat management device of claim 7-9 any one of them LED, which is characterized in that the controller includes：
Setting unit, maximum working temperature, lower working temperature and the lower working temperature for the LED to be arranged correspond to
Start-up operation when pwm signal duty ratio, and be arranged between the maximum working temperature and the lower working temperature N number of
Intermediate operating temperature, and the duty ratio of the corresponding pwm signal of N number of intermediate operating temperature is set, wherein N is positive integer, compared with
The corresponding duty ratio of high operating temperature is less than the corresponding duty ratio of lower operating temperature；
Control unit, for when the operating temperature of the LED is equal to any intermediate operating temperature, generating current operating temperature pair
The pwm signal answered；When the operating temperature of the LED rises to the ceiling temperature, stop generating pwm signal, until described
When the operating temperature of LED drops to the lower limit temperature, pwm signal when starting to work is generated.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810377919.0A CN108495418B (en) | 2018-04-25 | LED thermal management method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810377919.0A CN108495418B (en) | 2018-04-25 | LED thermal management method and device |
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| Publication Number | Publication Date |
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| CN108495418A true CN108495418A (en) | 2018-09-04 |
| CN108495418B CN108495418B (en) | 2024-11-15 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110087360A (en) * | 2019-04-10 | 2019-08-02 | 北京乐驾科技有限公司 | The adjustable LED of brightness and brightness adjusting method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101276556A (en) * | 2007-03-30 | 2008-10-01 | 群康科技(深圳)有限公司 | Drive circuit and drive method for LED as well as LED device |
| CN102426823A (en) * | 2011-09-21 | 2012-04-25 | 友达光电股份有限公司 | Active protection circuit for controlling temperature of light-emitting diode (LED) backlight driver |
| CN102918578A (en) * | 2010-05-28 | 2013-02-06 | Nec显示器解决方案株式会社 | Projection display device |
| US20150035438A1 (en) * | 2013-08-05 | 2015-02-05 | Cal-Comp Electronics & Communications Company Limited | Over-temperature protecting apparatus and over-temperature protecting method thereof |
| CN104684216A (en) * | 2015-02-11 | 2015-06-03 | 广州市德晟照明实业有限公司 | Over-temperature protection circuit and method for LED lamp |
| CN208143540U (en) * | 2018-04-25 | 2018-11-23 | 广东工业大学 | A kind of heat management device and system of LED |
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101276556A (en) * | 2007-03-30 | 2008-10-01 | 群康科技(深圳)有限公司 | Drive circuit and drive method for LED as well as LED device |
| CN102918578A (en) * | 2010-05-28 | 2013-02-06 | Nec显示器解决方案株式会社 | Projection display device |
| CN102426823A (en) * | 2011-09-21 | 2012-04-25 | 友达光电股份有限公司 | Active protection circuit for controlling temperature of light-emitting diode (LED) backlight driver |
| US20150035438A1 (en) * | 2013-08-05 | 2015-02-05 | Cal-Comp Electronics & Communications Company Limited | Over-temperature protecting apparatus and over-temperature protecting method thereof |
| CN104684216A (en) * | 2015-02-11 | 2015-06-03 | 广州市德晟照明实业有限公司 | Over-temperature protection circuit and method for LED lamp |
| CN208143540U (en) * | 2018-04-25 | 2018-11-23 | 广东工业大学 | A kind of heat management device and system of LED |
Non-Patent Citations (1)
| Title |
|---|
| 陈英;冯全源;: "滞流控制实现LED恒流驱动", 微电子学与计算机, no. 06, 5 June 2010 (2010-06-05), pages 193 - 196 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110087360A (en) * | 2019-04-10 | 2019-08-02 | 北京乐驾科技有限公司 | The adjustable LED of brightness and brightness adjusting method |
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