CN102221667B - Measuring apparatus and method for diode chip - Google Patents
Measuring apparatus and method for diode chip Download PDFInfo
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- CN102221667B CN102221667B CN 201010151743 CN201010151743A CN102221667B CN 102221667 B CN102221667 B CN 102221667B CN 201010151743 CN201010151743 CN 201010151743 CN 201010151743 A CN201010151743 A CN 201010151743A CN 102221667 B CN102221667 B CN 102221667B
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Abstract
The invention discloses a measuring apparatus and method for a diode chip. The diode chip is provided on a thermal conduction element. The measuring apparatus firstly measures the instant starting current of the diode chip and measures a first temperature corresponding to the instant starting current of the thermal conduction element. After the operation of the diode chip starts, the measuring apparatus adjusts the temperature of the thermal conduction element to a second temperature such that the current of the diode chip equals to the instant starting current. The measuring apparatus calculates the attributes of the diode chip based on the practical power of the diode chip and the temperature difference between the first temperature and the second temperature.
Description
Technical field
The invention relates to a kind of measuring equipment and method for measurement of diode chip for backlight unit, and particularly can exchange in order to measurement measuring equipment and the method for measurement of electrically driven (operated) diode chip for backlight unit relevant for a kind of.
Background technology
In recent years, light emitting diode (Light Emitting Diode, LED) development of semiconductor technology is due to the lifting of technology, make chip light emitting efficient significantly promote, also therefore be increased in the application of each side, such as from projection pen to the application etc. of throwing light on, significantly increased the scope of using.In addition, LED has also that volume is little, the life-span is long, the low pollution and the advantages such as low-cost, has more the characteristics such as the good and dynamic color control of color saturation on optical characteristics, therefore makes the LED correlation technique become the technology that attracts most attention at present.
Generally speaking, LED is widely known by the people exactly and has more power saving compared with the conventional lights source most, the less advantage of environmental protection and volume more, the appearance of alternating current driving LED makes it more competitive on illuminator is used, but must face equally the chip electricity problem low with the conversion efficiency of light with direct-current drive LED, the chip of LED is still most input electric energy is converted to heat energy at present, and only small part is converted to light, so problems of excessive heat is still the main themes of LED technical development.Under the limited situation of present LED chip luminescence efficiency, most power supply is converted into heat, also makes heat generation density significantly promote.Problems of excessive heat has become the bottleneck of technical development.And being defined as the temperature (Junction Temperature) at LED chip junction place, thermal resistance deducts environment temperature, then divided by the value of power input gained.This thermal resistance value is in the LED encapsulation, the standard of judgement heat-sinking capability quality, if thermal resistance value is larger, the expression heat-sinking capability is poorer; Otherwise if thermal resistance value is less, heat-sinking capability is better.Therefore thermal resistance value provides a criterion.
In the LED encapsulation, often need to do to heat dissipation element the restriction of maximum thermal resistance, so the measurement of element thermal resistance, there is its importance that its representativeness is also arranged.In the parameter of calculating thermal resistance, ambient temperature is utilized thermocouple (Thermo couple) can be easy to measure and is arrived.For a heater element, its power input is also known, can calculate out.But in a complete encapsulation, just be difficult to directly measure the junction temperature of chip, therefore generally need to a kind of indirectly electrical method for measurement, obtain chip junction temperature.If the method can measure fast and accurately the heat of checking element and pass characteristic and hot impact on optical characteristics, the heat that will help to promote LED chip passes design and checking, reaches effective radiating effect.
The situation that the alternating current driving LED is identical with direct-current drive LED is all can't directly measure to obtain the chip contact temperature, all must convert with the electrical method for measurement of indirect and obtain, it is because the power supply of inputting is alternating current that but the thermal resistance method for measurement of alternating current driving LED is different from direct-current drive LED, voltage and the non-certain value of electric current of input, and be a sinusoidal period ripple, so method for measurement will be different with direct-current drive LED.The foundation of alternating current driving LED packaging thermal resistance measurement technology will help to promote the package cooling design of alternating current driving LED.
TaiWan, China patent 200925571 discloses a kind of device that measures LED characteristic and chip temperature, and its measurement process mainly contains two steps.First step is to utilize the electric current of conductive form and input pulse form to measure TSP (the Temperature Sensitive Parameter) calibration curve of its bias value and temperature.Second step is the magnitude of voltage that measures in the practical operation situation, recycling TSP calibration curve conversion light-emitting diode chip for backlight unit temperature and packaging thermal resistance value.But this Apparatus and method for is only to measure direct-current drive LED.In addition, this front case only is confined to measure the direct supply light emitting diode, and also no-trump light, heat and electric three specific character method for measurement combine.
U. S. application number of patent application US0815403043 discloses the method for measurement of the junction temperature of an alternating current driving LED, its method for measurement is the light-emitting diode heat resistance method for measurement with reference to direct supply, and just alternating-current light emitting diode is that mode with input ac voltage measures.Its measurement process mainly contains two stages.In the phase one measurement step, first give LED one trigger voltage, control the different LED substrate temperature, and measure electric current and the substrate temperature of LED, to obtain the family curve of LED.In the subordinate phase measurement step, the small resistance of connecting in addition operating practically the input of specified alternating voltage, and utilizes the data acquisition module of two-way to obtain simultaneously the resistance value of resistance and the magnitude of voltage of alternating current.Afterwards again by the magnitude of voltage of the trigger voltage of finding out LED in voltage waveform and the resistance that corresponds to thereof, to be converted into current value.In addition, then the current change quantity of the current value after obtaining its initial current value and reaching thermal equilibrium, its temperature variation obtained to convert according to above-mentioned family curve.And above-mentioned temperature variation is added initial temperature value, is the diode junction temperature.
More front case patent although TaiWan, China patent 200925571 possesses the function of rapid measuring light-emitting diode heat resistance, only is confined to measure the direct supply light emitting diode, and also no-trump light, heat and electric three specific character method for measurement combine.Though U. S. application number of patent application US0815403043 method for measurement can measure the AC power light emitting diode, but measuring program is complicated, need two stage steps, and needing in addition when carrying out second step, resistance of serial connection measures, and the resistance sizes difference will affect measurement, select again the resistance of which kind of resistance because being difficult for judgement, therefore it has many variablees and inconvenience on measuring.
Summary of the invention
The invention provides a kind of measuring equipment and method for measurement thereof of diode chip for backlight unit, it can accurately and rapidly measure the electrical characteristics of diode chip for backlight unit at certain temperature.
The present invention proposes a kind of method for measurement of diode chip for backlight unit.Above-mentioned method for measurement comprises this diode chip for backlight unit is arranged on heat-conduction component.Afterwards, voltage is applied to this diode chip for backlight unit, and by the instant starting currents of this diode chip for backlight unit of current measurement unit measuring, and is the first temperature by the temperature that the measuring temp element measures this heat-conduction component.After this voltage was applied to this diode chip for backlight unit, beginning was controlled the temperature of this heat-conduction component, until the electric current of this current measurement this diode chip for backlight unit that the unit measures equals this instant starting currents by temperature control modules.After the temperature of controlling this heat-conduction component, if the electric current of this current measurement this diode chip for backlight unit that the unit measures equals this instant starting currents, the temperature that measures this heat-conduction component by this measuring temp element is the second temperature.
The method for measurement of described diode chip for backlight unit more comprises:
Calculate the real power of this diode chip for backlight unit when applying this voltage;
This first temperature is deducted this second temperature, in the hope of the temperature difference between this first temperature and this second temperature; And
With this temperature difference divided by this real power, in the hope of a thermal resistance value of this diode chip for backlight unit.
This voltage is alternating voltage, and the electric current of this diode chip for backlight unit that is measured and this instant starting currents are rms current.
This voltage is DC voltage.
This diode chip for backlight unit has at least one light emitting diode.
The present invention proposes a kind of measuring equipment.Above-mentioned measuring equipment comprises heat-conduction component, voltage source, current measurement unit, measuring temp element and temperature control modules.Described heat-conduction component is suitable for arranging above-mentioned diode chip for backlight unit.Described voltage source is suitable for voltage is applied to above-mentioned diode chip for backlight unit.Described current measurement unit is suitable for when voltage source applies voltage at diode chip for backlight unit, measures the electric current of diode chip for backlight unit.Described measuring temp element is suitable for measuring the temperature of heat-conduction component.Described temperature control modules is suitable for controlling the temperature of heat-conduction component.Wherein when voltage source begins to apply voltage at diode chip for backlight unit, the instant starting currents of the above-mentioned diode chip for backlight unit of current measurement unit measuring, and the temperature that the measuring temp element measures above-mentioned heat-conduction component is the first temperature.Wherein after above-mentioned voltage was applied to diode chip for backlight unit, temperature control modules began the temperature of above-mentioned heat-conduction component is controlled to the second temperature, so that the electric current of above-mentioned current measurement diode chip for backlight unit that the unit measures equals above-mentioned instant starting currents.Above-mentioned the second temperature is not equal to the first temperature.
In one embodiment of this invention, above-mentioned measuring equipment calculates the real power of diode chip for backlight unit when applying above-mentioned voltage, and the first temperature is deducted the second temperature in the hope of the temperature difference between the first temperature and the second temperature, and said temperature is poor divided by the thermal resistance value of above-mentioned real power in the hope of diode chip for backlight unit.
In one embodiment of this invention, above-mentioned voltage is alternating voltage, and the electric current of the diode chip for backlight unit that is measured and instant starting currents are rms current.
In one embodiment of this invention, above-mentioned voltage is DC voltage.
In one embodiment of this invention, above-mentioned diode chip for backlight unit has at least one light emitting diode.
Based on above-mentioned, the measuring equipment of diode chip for backlight unit of the present invention and method for measurement not only can be in order to measure the electrical characteristics with the diode chip for backlight unit of direct-current drive, also can be in order to measure to exchange the electrical characteristics of electrically driven (operated) diode chip for backlight unit.In addition, the present invention uses the temperature of conductive form to control the control that can reach quite quick and high accurancy and precision, but and light, heat and the electrical characteristics of the different chip contact temperatures of rapid measuring.
Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.
Description of drawings
Fig. 1 is the schematic diagram according to the measuring equipment of one embodiment of the invention;
Fig. 2 is flow through when not yet applying voltages to the diode chip for backlight unit electric current of diode chip for backlight unit and the graph of a relation of time of the voltage source in Fig. 1;
Fig. 3 is flow through when beginning to apply voltages to the diode chip for backlight unit electric current of diode chip for backlight unit and the graph of a relation of time of the voltage source in Fig. 1;
Fig. 4 is when the temperature control modules in Fig. 1 is controlled the temperature of heat-conduction component, the electric current of diode chip for backlight unit and the graph of a relation of time;
Fig. 5 is the schematic diagram according to the measuring equipment of another embodiment of the present invention.
Wherein, Reference numeral
100,500: measuring equipment
101,264: radiating module
102,266: temperature control component
104: heat-conduction component
105: insulation film
106: diode chip for backlight unit
107: pin
108: insulation cover
110: temperature controller
112: the power supply ammeter
114: data reading card
116: retaining element
118: the measuring temp element
258: integrating sphere
Embodiment
The embodiment of the present invention can make the electrical characteristics of LED measure and measure with thermal characteristics to reach more complete, result fast and accurately.The method also can be in order to measure to exchange the electrical characteristics of electrically driven (operated) diode chip for backlight unit except measuring the electrical characteristics with the diode chip for backlight unit of direct-current drive.Below describe the present invention for some embodiment, but the present invention is not subject to illustrated embodiment.Again, also appropriate combination can be mutually done between illustrated embodiment, the content of single embodiment need not be limited to.
Please refer to Fig. 1, Fig. 1 is the schematic diagram according to the measuring equipment 100 of one embodiment of the invention.Consult Fig. 1, control in order to reach temperature, can control temperature by a temperature control modules of measuring equipment 100.Above-mentioned temperature control modules can comprise a temperature control component 102, such as: well heater, thermoelectric cooling module etc.Wherein thermoelectric cooling module can cool the temperature to lower than room temperature, measures at the temperature lower than room temperature to allow measuring equipment 100.The thermal source that temperature control component 102 is taken out of (Heat source) can be reached stable heat radiation by radiating module (Thermal Module) 101, especially can take away the heat energy of thermoelectric cooling module when thermoelectric cooling module operates.Do not need radiating module 101 if adopt well heater to heat again.Temperature control modules also comprises some control circuits in addition, and the control circuit of this class is for example temperature controller 110, to reach temperature controlled effect.Temperature controller 110 can be the controllers such as proportion integration differentiation (proportional-integral-derivative, PID) controller, shutdown reactor cooling (shutdown reactor cooling, SRC) controller.
The present invention more proposes a kind of measurement mode of utilizing hot conductive form (Thermal Conductive Type), and diode chip for backlight unit heating or refrigeration with to measuring reach desired temperature.For example be connected with temperature control component 102 by a heat-conduction component 104.So heat-conduction component 104 can be fast and the temperature of temperature control component 102 reach balance, obtain desired temperature.Heat-conduction component 104 such as be structured metal layer with high heat-conduction coefficient, such as the structural sheet of copper, bronze, aluminium etc.In an embodiment of the present invention, heat-conduction component 104 top layers are coated with the insulation film 105 of a high heat-conduction coefficient, and the material of insulation film 105 is for example that aluminium oxide, class are bored carbon (Diamond-like carbon, DLC) film etc.The purpose of insulation film 105 is to utilize the characteristic of its electrical isolation, makes diode chip for backlight unit 106 its electric current of unlikely generation when test have part to have influence on the accuracy of measurement from the phenomenon of heat-conduction component 104 leakages.In addition, measuring equipment 100 can comprise a heat-insulating cover 108, is arranged on heat-conduction component 105, to consist of a heat insulation space.Insulation cover 108 for example more available heat insulation silk flosses and bakelite combines.
In the present embodiment, the diode chip for backlight unit 106 that test comprises at least one light emitting diode, and diode chip for backlight unit 106 is to drive with alternating current.Yet the present invention is not as limit, and for example in an embodiment of the present invention, the diode chip for backlight unit 106 that test does not include light emitting diode, and only has general non-diode that can be luminous.For example in another embodiment of the present invention, diode chip for backlight unit 106 is to drive with direct current again.In addition, the diode chip for backlight unit 106 that test for example can be attached on heat-conduction component 104 by heat-conducting cream, and is in insulated space in insulation cover 108, with equilibrium temperature that must be better.Yet noticeable, insulation cover 108 is not indispensable element for the purpose of the present invention.In addition, in an embodiment of the present invention, measuring equipment 1 () 0 comprises two retaining elements 116, contacts with two pins 107 of diode chip for backlight unit 106 respectively, so that diode chip for backlight unit 106 is fixed on heat-conduction component 104, and make the measurement personnel can promptly change diode chip for backlight unit 106.In addition, affect the result of the heat survey of diode chip for backlight unit 106 because absorbing light for fear of retaining element 116, in other embodiment of the present invention, retaining element 116 can be selected the material of white material, or plates barium sulphate on retaining element 116.The mechanism design of the power supply of diode chip for backlight unit 106 can be provided because of retaining element 116, therefore can not need to weld in addition outlet, connect two pins 107 of voltage source 112 and diode chip for backlight unit 106.
Above-mentioned temperature control modules separately comprises a measuring temp element 118, is located at the junction of substrate and the heat-conduction component 104 of diode chip for backlight unit 106, and is placed in the below of diode chip for backlight unit 106, is used for the temperature of detecting heat-conduction component 104.Basically, because heat-conduction component 104 and insulation film 105 have high heat-conduction coefficient, therefore the temperature that measuring temp element 118 is measured except meeting equals the temperature of heat-conduction component 104, also can equal the substrate temperature of diode chip for backlight unit 106.Measuring temp element 118 can be thermocouple (thermocouple), thermistor (thermistor) or resistance temperature detector (Resistance Temperature Detector, RTD).
In the flow process that measures diode chip for backlight unit 106, can first utilize above-mentioned temperature control modules that the substrate temperature of diode chip for backlight unit 106 and the temperature of heat-conduction component 104 are controlled at a certain equilibrium temperature, for example: 25 ℃.At this moment, voltage source 112 not yet applies a voltage to diode chip for backlight unit 106, and the junction temperature (junction temperature) because of thermally equilibrated cause diode chip for backlight unit 106 can be identical with the temperature of heat-conduction component 104 again.Afterwards, voltage source 112 applies voltages to diode chip for backlight unit 106, so that diode chip for backlight unit 106 comes into operation.Begin to apply voltages to the baseline of diode chip for backlight unit 106 at voltage source 112, current measurement unit 114 measures the instant starting currents of diode chip for backlight unit 106, and the temperature that measuring temp element 118 measures heat-conduction components 104 is one first temperature.In an embodiment of the present invention, if diode chip for backlight unit 106 is to drive with alternating current, the instant starting currents of current measurement unit 114 diode chip for backlight unit that measures 106 root-mean-square value of first positive half-wave of electric current of diode chip for backlight unit 106 that can equal to flow through.In other words, above-mentioned instant starting currents is rms current.Therefore the time, diode chip for backlight unit 106 is not subject to the impact of thermal effect, therefore corresponding current value when the junction temperature that instant starting currents is diode chip for backlight unit 106 is the first temperature.
Please refer to Fig. 2 and Fig. 3, wherein Fig. 2 is flow through when not yet applying voltages to diode chip for backlight unit 106 electric current of diode chip for backlight unit 106 and the graph of a relation of time of voltage source 112, and Fig. 3 is voltage source 112 flow through when beginning to apply voltages to diode chip for backlight unit 106 electric current of diode chip for backlight unit 106 and the graph of a relation of time.Wherein, as shown in Figure 2, when voltage source 112 not yet was applied to diode chip for backlight unit 106, corresponding current value was zero.Shown in figure three, when current measurement unit 114 measured the instant starting currents of diode chip for backlight unit 106, it can be according to t
1To t
2The current value of the diode chip for backlight unit that detects 106 during this time calculate the rms current of diode chip for backlight unit 106, and resulting rms current is the instant starting currents of diode chip for backlight unit 106.In addition, in the present invention one implements, if diode chip for backlight unit 106 is with direct voltage drive, the current waveform that detects of current measurement unit 114 will can be not as shown in Figure 3, in the case, can begin to be applied to a Preset Time interval after diode chip for backlight unit 106 according to voltage source 112, the electric current of the diode chip for backlight unit 106 that is measured calculates above-mentioned instant starting currents.Wherein, above-mentioned Preset Time interval is for example less than the millisecond grade.
After voltage was applied to diode chip for backlight unit 106, because of the cause of power consumption, the temperature of diode chip for backlight unit 106 can raise gradually.The cause that raises because of the temperature of diode chip for backlight unit 106 again, the electric current of diode chip for backlight unit 106 also can increase.For measuring the characteristic of diode chip for backlight unit 106, after voltage is applied to diode chip for backlight unit 106, above-mentioned temperature control modules begins to control the temperature of heat-conduction component 104, until the electric current of the diode chip for backlight unit 106 that current measurement unit 114 is measured equals above-mentioned instant starting currents.In addition, after the temperature of heat-conduction component 104 is controlled, if the electric current of current measurement unit 114 diode chip for backlight unit that measures 106 equals above-mentioned instant starting currents, the temperature that measures the heat-conduction component 104 of this moment by measuring temp element 118 is one second temperature.Noticeable, if diode chip for backlight unit 106 is to drive with alternating voltage, the electric current of the diode chip for backlight unit 106 that current measurement unit 114 measured also is its rms current.
Please refer to Fig. 4, Fig. 4 is when temperature control modules is controlled the temperature of heat-conduction component 104, the electric current of diode chip for backlight unit 106 and the graph of a relation of time.One implement at this, the instant starting currents of the diode chip for backlight unit 106 that current measurement unit 114 is measured is 27.05732mA, and because the cause of thermal effect, the current boost of diode chip for backlight unit 106 arrives approximately 28mA.Afterwards, temperature control modules begins to downgrade the temperature of heat-conduction component 104.Because of the decline of the temperature of heat-conduction component 104, the junction temperature of diode chip for backlight unit 106 also can descend, and then makes the electric current of diode chip for backlight unit 106 also and then descend.After the temperature of heat-conduction component 104 descends, if the electric current of the diode chip for backlight unit 106 that current measurement unit 114 is measured equals above-mentioned instant starting currents, the temperature of the heat-conduction component 104 that measured this moment of measuring temp element 118 is the second above-mentioned temperature.Take Fig. 4 as example, begin to downgrade 500 seconds after the temperature of heat-conduction component 104 at temperature control modules, the electric current of diode chip for backlight unit 106 namely equals the instant starting currents of diode chip for backlight unit 106, and the temperature that this moment, measuring temp element 118 was measured is the second above-mentioned temperature.
In an embodiment of the present invention, the real power (Real Power) of diode chip for backlight unit 106 when being applied in voltage calculated in current measurement unit 114 meetings, if the real power of diode chip for backlight unit 106 is with P
RealExpression, real power P
RealCan represent by following equation:
P
apparent＝V
rms×I
rms (2)
Wherein, V (t) is for putting on the magnitude of voltage of diode chip for backlight unit 106 at time point t;
I (t) is the current value of the diode chip for backlight unit 106 of flowing through at time point t;
T is the current/voltage sample period, and in an embodiment of the present invention, if diode chip for backlight unit 106 is driven by alternating voltage, T is the cycle of this alternating voltage;
P
ApparentApplied power for diode chip for backlight unit 106;
V
rmsVRMS voltage root mean square for diode chip for backlight unit 106;
I
rmsRms current value for diode chip for backlight unit 106;
PF is the power factor (Power Factor) of diode chip for backlight unit 106.
Afterwards, a counting circuit of measuring equipment 100 (not icon) or above-mentioned current measurement unit 114 meetings deduct the second above-mentioned temperature with the first above-mentioned temperature, in the hope of the temperature difference between the first temperature and the second temperature.For instance, if the first above-mentioned temperature is T
J, the second above-mentioned temperature is T
C, and above-mentioned temperature difference is Δ T:
ΔT＝T
J-T
C (3)
Afterwards, above-mentioned counting circuit or current measurement unit 114 with temperature difference Δ T divided by real power P
Real, in the hope of a thermal resistance value of diode chip for backlight unit 106.The thermal resistance value of supposing diode chip for backlight unit 106 equals R
JC:
Fig. 5 is the schematic diagram according to the measuring equipment 500 of another embodiment of the present invention.Consult Fig. 5, the basic structure of the present embodiment still with the structural similarity of Fig. 1, but insulation cover 108 can be changed into integrating sphere 258 and heat-conduction component 104 and fit together, and for example utilizes chip fixing structure to fix diode chip for backlight unit, and it also can prevent the light leak of integrating sphere 258.Temperature control unit below heat-conduction component 104 for example includes temperature control component 102 and radiating module 101.So heat-conduction component 104 can be fast and temperature control component 102 reach uniform temp.Radiating module 101 coordinates temperature control component 102 to operate together in addition, and the variation that reaches temperature is controlled.The electric current of diode chip for backlight unit for example can provide by power supply ammeter 112 in addition.Power supply ammeter 112 is read the magnitude of voltage of diode simultaneously.Also can increase again data reading card 114 in addition, read magnitude of voltage more accurately.In addition, temperature controller 110 also can be controlled simultaneously another temperature control component 266 and control integrating sphere 258 is done temperature except the temperature that can control temperature control component 102.Temperature control component 266 also coordinates radiating module 264 to operate together.
The present embodiment can the Fast Installation diode chip for backlight unit and power supply is provided, and need not weld the derivation line.Again integrating sphere is designed to heatable spheroid, can reaches and control the heat-conduction component operating temperature and control environment temperature, and then obtain the relation of optical characteristics and environment temperature (or heat-conduction component operating temperature).
The effect of integrating sphere, the light that for example sends with the scattering light-emitting diode chip for backlight unit, and integration adds stack up and gets its optical characteristics, so allows the present invention also can measure simultaneously the function of optical characteristics and thermal characteristics.For example when being input as actual input current, doing optical characteristics and measure; When the input Weak current, do chip temperature and thermal resistance and measure.Integrating sphere can be designed as the function of thermostat characteristic, makes this device can do the control of environment temperature, with the optical characteristics of observation light emitting diode and the relation of environment temperature.
Certainly; the present invention also can have other various embodiments; in the situation that do not deviate from spirit of the present invention and essence thereof; those of ordinary skill in the art work as can make according to the present invention various corresponding changes and distortion, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the present invention.
Claims (10)
1. the method for measurement of a diode chip for backlight unit, is characterized in that, comprising:
This diode chip for backlight unit is arranged on a heat-conduction component;
One voltage is applied to this diode chip for backlight unit, and by the starting current in a flash of this diode chip for backlight unit of current measurement unit measuring, and is one first temperature by the temperature that a measuring temp element measures this heat-conduction component;
After this voltage was applied to this diode chip for backlight unit, beginning was controlled the temperature of this heat-conduction component, until the electric current of this current measurement this diode chip for backlight unit that the unit measures equals this instant starting currents by a temperature control modules; And
After the temperature of controlling this heat-conduction component, if the electric current of this current measurement this diode chip for backlight unit that the unit measures equals this instant starting currents, the temperature that measures this heat-conduction component by this measuring temp element is one second temperature.
2. the method for measurement of diode chip for backlight unit according to claim 1, is characterized in that, more comprises:
Calculate the real power of this diode chip for backlight unit when applying this voltage;
This first temperature is deducted this second temperature, in the hope of the temperature difference between this first temperature and this second temperature; And
With this temperature difference divided by this real power, in the hope of a thermal resistance value of this diode chip for backlight unit.
3. the method for measurement of diode chip for backlight unit according to claim 1, is characterized in that, this voltage is alternating voltage, and the electric current of this diode chip for backlight unit that is measured and this instant starting currents are rms current.
4. the method for measurement of diode chip for backlight unit according to claim 1, is characterized in that, this voltage is DC voltage.
5. the method for measurement of diode chip for backlight unit according to claim 1, is characterized in that, this diode chip for backlight unit has at least one light emitting diode.
6. the measuring equipment of a diode chip for backlight unit, is characterized in that, comprising:
One heat-conduction component is used for arranging this diode chip for backlight unit;
One voltage source is used for a voltage is applied to this diode chip for backlight unit;
One current measurement unit is used for measuring the electric current of this diode chip for backlight unit when this voltage source applies this voltage at this diode chip for backlight unit;
One measuring temp element is for the temperature that measures this heat-conduction component; And
One temperature control modules is for the temperature of controlling this heat-conduction component;
Wherein when this voltage source begins to apply this voltage at this diode chip for backlight unit, the starting current in a flash of this this diode chip for backlight unit of current measurement unit measuring, and the temperature that this measuring temp element measures this heat-conduction component is one first temperature;
Wherein after this voltage is applied to this diode chip for backlight unit, this temperature control modules begins the temperature of this heat-conduction component is controlled to one second temperature, so that the electric current of this current measurement this diode chip for backlight unit that the unit measures equals this instant starting currents, and this second temperature is not equal to this first temperature.
7. the measuring equipment of diode chip for backlight unit according to claim 6, it is characterized in that, this current measurement unit calculates the real power of this diode chip for backlight unit when applying this voltage, this first temperature is deducted this second temperature in the hope of the temperature difference between this first temperature and this second temperature, and with this temperature difference divided by the thermal resistance value of this real power in the hope of this diode chip for backlight unit.
8. the method for measurement of diode chip for backlight unit according to claim 6, is characterized in that, this voltage is alternating voltage, and the electric current of this diode chip for backlight unit that is measured and this instant starting currents are rms current.
9. the method for measurement of diode chip for backlight unit according to claim 6, is characterized in that, this voltage is DC voltage.
10. the method for measurement of diode chip for backlight unit according to claim 6, is characterized in that, this diode chip for backlight unit has at least one light emitting diode.
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| TWI482233B (en) | 2012-08-14 | 2015-04-21 | Ind Tech Res Inst | Method and appartus for detecting relationship between thermal and electrical properties of semiconductor device |
| CN103630820A (en) * | 2013-12-03 | 2014-03-12 | 黑龙江省计量科学研究院 | High-power LED heat resistance measuring device and method of measuring high-power LED heat resistance thereby |
| CN104459507A (en) * | 2014-11-27 | 2015-03-25 | 深圳市华测检测技术股份有限公司 | Multi-channel detecting system for detecting optical performance of LED chip |
| CN104459506A (en) * | 2014-11-27 | 2015-03-25 | 深圳市华测检测技术股份有限公司 | Multipath detection system for LED chip |
| CN104459568A (en) * | 2014-11-27 | 2015-03-25 | 深圳市华测检测技术股份有限公司 | LED chip detection and analysis system |
| CN107843762B (en) * | 2017-12-01 | 2023-08-15 | 北京华峰测控技术有限公司 | Measuring circuit and method for on-state voltage drop of wafer die |
| CN113494968B (en) * | 2020-03-19 | 2022-11-25 | 长鑫存储技术有限公司 | Temperature measurement and temperature calibration method and temperature measurement system |
| CN117630620A (en) * | 2023-11-16 | 2024-03-01 | 深圳市拓睿特科技有限公司 | Photoelectric product performance detection equipment |
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| US5639163A (en) * | 1994-11-14 | 1997-06-17 | International Business Machines Corporation | On-chip temperature sensing system |
| US6612738B2 (en) * | 2000-03-08 | 2003-09-02 | Infineon Technologies | Method for determining the temperature of a semiconductor chip and semiconductor chip with temperature measuring configuration |
| TW200925571A (en) * | 2007-12-14 | 2009-06-16 | Ind Tech Res Inst | Apparatus and method for measuring character and chip temperature of LED |
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| US7052180B2 (en) * | 2002-01-04 | 2006-05-30 | Kelvin Shih | LED junction temperature tester |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5639163A (en) * | 1994-11-14 | 1997-06-17 | International Business Machines Corporation | On-chip temperature sensing system |
| US6612738B2 (en) * | 2000-03-08 | 2003-09-02 | Infineon Technologies | Method for determining the temperature of a semiconductor chip and semiconductor chip with temperature measuring configuration |
| TW200925571A (en) * | 2007-12-14 | 2009-06-16 | Ind Tech Res Inst | Apparatus and method for measuring character and chip temperature of LED |
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