CN201008224Y

CN201008224Y - Luminous load driving device

Info

Publication number: CN201008224Y
Application number: CNU2007200047249U
Authority: CN
Inventors: 周勤; 翟宏伟; 刘咸瑞; 李自林
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-02-09
Filing date: 2007-02-09
Publication date: 2008-01-16
Anticipated expiration: 2017-02-09

Abstract

A luminous loading drive device comprises a drive unit, a switch unit, a detecting unit and a control unit, an input end, and an output end, wherein the drive unit is utilized for driving one or more luminous loadings to shine, the switch unit is employed to control the make-and-break of the connection of the drive unit and one or more luminous loadings, the detecting unit is used to detect the temperature of the one or more luminous loadings and to export relative temperature signals according to the temperature of the one or more luminous loadings, the control unit is employed to control the make-and-break of the switch unit according to the correspondent control signals of the temperature signals, and the input end is connected with the output end of the detecting unit, the output end is in connected with the switch unit. The controlling of the switch unit can be realized by the control unit according to the corresponding temperature signals, further the power consumption of the luminous loadings can be controlled effectively, and thereby the power consumption can be reduced when the temperature of the luminous loadings is too high. The utility model can avoid overheating of the luminous loadings to prolong the service life of the device.

Description

The luminous load drive unit

Technical field

The utility model relates to a kind of luminous load drive unit.

The background skill originally

The high power consumption of light-emitting diode or other luminous loads can improve its internal temperature, cause its internal temperature to surpass maximum operating range, thereby cause that light-emitting diode or other luminous loads produce superheating phenomenon, usually, overheated luminous flux and the life-span that can reduce light-emitting diode or other luminous loads again greatly.

Therefore the problem that how to solve existing luminous load existence has become the technical problem that those skilled in the art need to be resolved hurrily in fact.

The utility model content

The purpose of this utility model is to provide a kind of luminous load drive unit, and is overheated to prevent luminous load, and then prolongs its useful life.

In order to achieve the above object, the utility model provides a kind of luminous load drive unit, and it comprises: be used to drive the luminous driver element of one or more luminous loads; Be used to control the switch element of the break-make that described driver element is connected with described one or more luminous loads; Be used to detect the temperature of described one or more luminous loads, and export the detecting unit of relevant temperature signal according to the temperature of described one or more luminous loads; And input is connected with described detecting unit output, and its output is connected with described switch element, is used for producing according to the temperature signal of input the control unit of the folding of the described switch element of corresponding control signals.

Wherein, described luminous load be light-emitting diode or organic electroluminescent LED (Organic Light-EmittingDiode, OLED); Described driver element is for producing the current drives unit of drive current; Described control unit comprises the pwm switch controller that has corresponding duty cycle signals according to described temperature signal generation, the minimum duty cycle of described pwm switch controller output signal is not less than default duty ratio, and described pwm switch controller also can comprise according to described pulse width signal and judges whether the temperature of described one or more luminous loads exceeds preset temperature value and export first determining device of first count signal when the temperature of described one or more luminous loads exceeds preset temperature value; Described switch element also comprises one in order to described drive current is carried out first switch of flow-dividing control; Described control unit can comprise that also one is connected with described first switch and produces the shunt of flow-dividing control signal so that described drive current is shunted of the described first switch folding of control according to described temperature signal, and described shunt also comprises according to the inner signal relevant with described temperature signal of described shunt and judges whether the temperature of described one or more luminous loads exceeds preset temperature value is also exported second count signal when the temperature of described one or more luminous loads exceeds preset temperature value second determining device; Described switch comprises one or more in field effect transistor, transistor and the relay; Described detecting unit comprises first temperature sensor of exporting digital current potential temperature signal, also can comprise second temperature sensor of output analog temperature signal, also can comprise the three-temperature sensor of exporting digit period pulse temperature signal; Described luminous load drive unit can comprise also the temperature signal that is used for according to described detecting unit output judges whether the temperature of described one or more luminous loads exceeds preset temperature value, and produces the 3rd determining device of the 3rd count signal when the temperature of described luminous load exceeds preset temperature value; Be used for according to count signal control gate time to calculate the time that described one or more luminous load temperature continues to surpass preset temperature value, and when described gate time surpasses preset value the counter controller of output alarm signal and the fault detector that is used for sending fault-signal according to described alarm signal, wherein, described count signal comprises one or more in first count signal, second count signal and the 3rd count signal.

In sum, luminous load drive unit of the present utility model is realized can preventing that luminous load is overheated, and then prolonging its useful life the control of the power consumption of luminous load by the detection to the luminous load temperature.

Description of drawings

Fig. 1 is the basic framework schematic diagram of the utility model luminous load drive unit.

Fig. 2 is the embodiment schematic diagram of the utility model luminous load drive unit.

Fig. 3 a to Fig. 3 d is its output signal schematic diagram of different temperatures transducer that the utility model luminous load drive unit adopts.

Fig. 4 a to Fig. 4 b is the pwm switch controller input/output signal schematic diagram of the utility model luminous load drive unit.

Fig. 5 a to Fig. 5 e is example one schematic diagram of the utility model luminous load drive unit.

Fig. 6 a to Fig. 6 h is example two schematic diagrames of the utility model luminous load drive unit.

Fig. 7 a to Fig. 7 d is example three schematic diagrames of the utility model luminous load drive unit.

Fig. 8 a to Fig. 8 d is example four schematic diagrames of the utility model luminous load drive unit.

Embodiment

See also Fig. 1 and Fig. 2, luminous load drive unit 1 of the present utility model comprises at least: driver element 11, switch element 12, detecting unit 13, control unit 14, the 3rd determining device 15, counter controller 16 and fault detector 17.

It is luminous that described driver element 11 is used to drive one or more luminous loads, in the present embodiment, it is the current drives unit, promptly be used to produce the drive current of driven for emitting lights load 10, it can be by inductance L, diode D0, capacitor C is formed, in addition, those skilled in the art also can adopt other drive circuits according to actual needs, for example, adopt current source, described luminous load 10 is made up of light-emitting diode D1 ~ D3, but it is not to exceed with present embodiment, for example, its also can be organic electroluminescent LED (Organic Light-Emitting Diode, OLED).

Described switch element 12 is used to control the break-make that described driver element 11 is connected with described luminous load 10, usually it is connected with luminous load 10 with described driver element 11 respectively, it is that field effect pipe M1 and second switch are that field effect pipe M2 is formed by first switch, wherein, when field effect pipe M2 conducting, described driver element 11 is that driven for emitting lights diode D1 ~ D3 is luminous, when described field effect transistor M2 disconnects, light-emitting diode D1 ~ D3 promptly extinguishes, this shows, can realize control light-emitting diode D1 ~ D3 current effective value by the duty ratio of regulating field effect transistor M2 folding; Equally, can make the effective value of the electric current of the field effect transistor M1 that flows through that corresponding change takes place by the duty ratio of regulating field effect transistor M1 folding, because the shunting action of described field effect transistor M1, and then can make the drive current generation respective change of the light-emitting diode D1 ~ D3 that flows through that described driver element 11 produced, can realize control with this to light-emitting diode D1 ~ D3 power consumption, be noted that, described switch element 12 is not to exceed with present embodiment, it also can adopt other switching circuits, for example transistor or relay etc. according to actual needs.

Described detecting unit 13 is used to detect the temperature of described luminous load 10, and according to the temperature of described luminous load 10 output relevant temperature signal, it can comprise that the temperature signal of output is first temperature sensor of digital electric potential signal, see also Fig. 3 a, temperature is above preset value constantly at t1 as light-emitting diode D1 ~ D3, and the current potential OT1 of described first temperature sensor output at t1 saltus step takes place constantly; Described detecting unit 13 can comprise that also the temperature signal of output is second temperature sensor of analog signal, see also Fig. 3 b and Fig. 3 c, when the temperature T led of Light-Emitting Diode D1 ~ D3 raises in the time period gradually at t2 ~ t3, and in t3 ~ t4 temperature decline in the time period, the temperature signal OT2 of corresponding second temperature sensor output descends in the time period gradually at t2 ~ t3, and raises gradually in the time period at t3 ~ t4; Described detecting unit 13 can comprise that also the temperature signal of output is the three-temperature sensor of recurrent pulse digital signal, see also Fig. 3 d, surpass default temperature value in t5 moment light-emitting diode D1 ~ D3 temperature, the temperature signal OT3 of described three-temperature sensor output begins the burst pulse cycle signal exported constantly from t5, be noted that, for the temperature signal that makes the output of each temperature sensor suits the requirements, described detecting unit 13 also can be provided with corresponding auxiliary circuit, for example inverter circuit M3 etc.

Described control unit 14 inputs are connected with described detecting unit 13 outputs, its output is connected with described switch element 12, be used for producing the folding of the described switch element 12 of corresponding control signals according to the temperature signal of input, it comprises pwm switch controller 141 and shunt 142, wherein, described pwm switch controller 141 is provided with comparison signal input 141a, reference signal input 141b and output 141c, when comparison signal input 141a input sawtooth signal, shown in solid line among Fig. 4 a, reference signal input 141b imports simple level signal, its level is respectively in moment t6 and the saltus step of t7 generation constantly, shown in dotted line among Fig. 4 a, accordingly, the output signal of described output 141c is the pulse width signal with certain duty ratio, promptly in 0 ~ t6 time period, output duty cycle is the pulse width signal of q1, when described reference signal input 141b input signal at t6 saltus step takes place constantly, the pulse width signal duty ratio of corresponding output becomes q2, when described reference signal input 141b input signal at t7 saltus step takes place once more constantly, the duty ratio of the pulse width signal of the desirable output of output 141c is q3, shown in the dotted line among Fig. 4 b, but because pwm switch controller 141 self is defined as q4 (q4＞q3) with the minimum duty cycle of the pulse width signal of output, so begin constantly from t7, the duty ratio of the pulse width signal of the actual output of output 141c is q4, usually q4 is set according to national standard, be generally 70%, shown in the solid line among Fig. 4 b, in addition, described pwm switch controller 141 also can be provided with one first determining device 145, be used for judging according to described pulse width signal whether the temperature of described luminous load 10 exceeds preset temperature value and export first count signal when the temperature of described luminous load 10 exceeds preset temperature value, the temperature that is described luminous load 10 when usually, the pulse width signal duty ratios of exporting when described pwm switch controller 141 ideals are reduced to q4 has exceeded preset temperature value.Described shunt 142 is used for being connected with described first switch and producing the flow-dividing control signal of the described first switch folding of control so that described drive current is shunted according to described temperature signal, usually it produces the folding of the described field effect transistor M1 of High Speed Modulation signal controlling, and then control flows is through the effective value of the electric current of described field effect transistor M1, the operation principle of described shunt 142 is similar to existing LTC3783 chip operation principle, no longer describes in detail at this.Have again, described shunt 142 also can be provided with one second determining device 146, is used for judging according to the inner signal relevant with described temperature signal of described shunt whether the temperature of described luminous load 10 exceeds preset temperature value and export second count signal (being described in detail after please holding) when the temperature of described luminous load 10 exceeds preset temperature value.

Described the 3rd determining device 15 is used for judging according to the temperature signal of described detecting unit 13 outputs whether the temperature of described luminous load 10 exceeds preset temperature value, and when exceeding preset temperature value, the temperature of described luminous load 10 produces the 3rd count signal, for example, when described detecting unit 13 adopts first temperature sensor, its output OT1 output signal is shown in Fig. 3 a, the temperature that described the 3rd determining device 15 can be judged from the described constantly light-emitting diode D1 ~ D3 of t1 according to the signal of output OT1 output surpasses preset temperature value, in addition, when described detecting unit 13 adopts other temperature sensors, for example during second temperature sensor, described the 3rd determining device 15 also can be judged according to the corresponding temperature signal of input, not repeat them here.

Described counter controller 16 is used for according to count signal control gate time to calculate the time that described luminous load 10 temperature continue to surpass preset temperature value, and when described gate time surpasses preset value the output alarm signal, wherein, described count signal comprises first count signal, in second count signal and the 3rd count signal one or more, for example, described counter controller 16 adopts the 3rd count signal of the 3rd determining device output to count, as shown in Figure 2, when described the 3rd determining device 15 is judged the temperature preset temperature value that begins described light-emitting diode D1 ~ D3 from t1 constantly, therefore described counter controller 16 begins counting constantly from t1, it sends alarm signal when (i.e. 1 second) when described counter controller 16 gate times surpass preset value, it is noted that, but when if the gate time of described counter controller 16 does not also reach Preset Time, described the 3rd determining device 145 is judged described light-emitting diode D1 ~ D3 temperature and is not exceeded preset temperature value, then clear 0 signal of its corresponding output makes described counter controller clear 0.

Described fault detector 17 is used for sending fault-signal according to described alarm signal, and described fault detector 17 sends fault-signal, and it can be indicator light usually.

Example one:

See also Fig. 5 a ~ Fig. 5 e, when described detecting unit 13 adopts first temperature sensor, the output signal OT1 of described first temperature sensor inputs to described reference signal input 141b by field effect transistor M3, comparison signal input 141a inserts sawtooth signal, and adopt the triggering signal of first determining device 145 as counter controller 16, when the temperature that detects light-emitting diode D1 ~ D3 when described first temperature sensor surpasses default temperature value, the level of its output OT1 output (being the t8 moment) at once jumps to high level from low level, shown in Fig. 5 b, two input end signals of corresponding described pwm switch controller 141 are shown in Fig. 5 c, the signal of the output 141c of described pwm switch controller 141 is shown in Fig. 5 d, be noted that, begin constantly from t8, the duty ratio of the pulse width signal of its output is reduced to limit value q4, and then the power consumption of light-emitting diode D1 ~ D3 lowers gradually, simultaneously, the duty ratio that described first determining device 145 is judged the pulse width signal that described pwm switch controller 141 produces be reduced to limit value q4 constantly (being t8) surpass moment of preset temperature value for light-emitting diode D1 ~ D3 temperature, therefore it exports first count signal to described counter controller 16 constantly from t8, described counter controller 16 begins counting, when its count up to t9 constantly the duty ratio of the pulse width signal that produced of described pwm switch controller 141 still maintain q4, at this moment, when gate time has surpassed preset value, then described counter controller 16 output alarm signal alarm, shown in Fig. 5 e, described fault detector 17 sends fault-signal according to described alarm signal alarm constantly from t9.

Example two:

See also Fig. 6 a ~ 6h, when described detecting unit 13 adopts second temperature sensor, its output signal OT2 inserts described reference signal input 141b, comparison signal input 141a still inserts sawtooth signal, and still adopt the triggering signal of first judging unit 145 as counter controller 16, when the temperature T led of light-emitting diode D1 ~ D3 is raise gradually by initial stable temperature, shown in Fig. 6 b, the described second temperature sensor output OT2 output signal is shown in dotted line among Fig. 6 c, when Tled rises to t10 during the moment, the duty ratio of the pulse width signal of the output 141c output of corresponding described pwm switch controller 141 has been reduced to its limit value q4, shown in Fig. 6 d, therefore the current effective value that flows through described field effect transistor M2 constantly from t10 is reduced to minimum value, and then the power consumption of light-emitting diode D1 ~ D3 is adjusted to floor level, the temperature of light-emitting diode D1 ~ D3 begins to descend gradually thereupon, thereby realizes the temperature controlling to light-emitting diode D1 ~ D3, prolongs its useful life.

But if constantly to t10, because it is too small that the power consumption of described light-emitting diode D1 ~ D3 reduces amplitude, the speed that its temperature is risen slows down, promptly begin the temperature of light-emitting diode D1 ~ D3 constantly still to continue rising more by a small margin from t10, shown in Fig. 6 e, the corresponding described second temperature sensor output OT2 output signal is shown in dotted line among Fig. 6 f, but because the minimum duty cycle of the pulse width signal of the output 141c of described pwm switch controller 141 output is q4, the signal of therefore described output 141c output is shown in Fig. 6 g, at this moment, the duty ratio that described first determining device 145 is judged the pulse width signal that described pwm switch controller 141 produces be reduced to limit value q4 constantly (being t10) surpass moment of preset temperature value for light-emitting diode D1 ~ D3 temperature, therefore it exports first count signal to described counter controller 16 constantly from t10, described counter controller 16 begins counting, when it counts up to t11 during the moment, the duty ratio of the pulse width signal that described pwm switch controller 141 is produced still maintains q4, when this moment, gate time surpassed preset value, then from the constantly described counter controller 16 output alarm signal alarm of t11, shown in Fig. 6 h, described fault detector 17 sends fault-signal according to described alarm signal alarm constantly from t11, it is noted that, but when if the gate time of described counter controller 16 does not also reach Preset Time, described first determining device 145 is judged described light-emitting diode D1 ~ D3 temperature and is not exceeded preset temperature value, then clear 0 signal of its corresponding output makes described counter controller clear 0.

Example three:

See also Fig. 7 a ~ 7d, when described detecting unit 13 adopts three-temperature sensor, and with described pwm switch controller 141 comparison signal input 141a and input 141a ' of reference signal input 141b merging formation, the output signal of the output 141c of described pwm switch controller 141 is changed along with the variation of input signal (known to those skilled in the art the knowing of described merging method, do not repeat them here), then three-temperature sensor output OT3 is connected with described input 141a ', and still adopt the triggering signal of first judging unit 145 as counter controller 16, shown in Fig. 7 a, when the temperature signal of the output OT3 of three-temperature sensor output shown in Fig. 7 b, promptly when light-emitting diode D1 ~ the D3 temperature stabilization just often, the duty ratio of output OT3 output signal is bigger, as light-emitting diode D1 ~ when the D3 temperature is too high, output OT3 output signal becomes burst pulse cycle signal at moment t12, the desirable output signal of the output 141c of described pwm switch controller 141 should be consistent with the temperature signal of input, promptly shown in the dotted line among Fig. 7 c, but because described pwm switch controller 141 self is limited to q4 with the minimum duty cycle of the pulse width signal of output, so the signal of the actual output of described output 141c is shown in the solid line among Fig. 7 c, promptly begin the pulse width signal that output duty cycle is q4 constantly at t12, because reducing of duty ratio, the connection of field effect transistor M2 and opening time are than reducing, the current effective value that respective streams is crossed light-emitting diode D1 ~ D3 reduces, and then can reduce the temperature of light-emitting diode D1 ~ D3, simultaneously described first determining device 145 duty ratio of judging the pulse width signal that described pwm switch controller 141 produces be reduced to limit value q4 constantly (being t12) surpass moment of preset temperature value for light-emitting diode D1 ~ D3 temperature, therefore it exports first count signal to described counter controller 16 constantly from t12, described counter controller 16 begins counting, when it counts up to t13 during the moment, the duty ratio of the pulse width signal that described pwm switch controller 141 is produced still maintains q4, at this moment, when gate time surpasses preset value, then from the constantly described counter controller 16 output alarm signal alarm of t13, shown in Fig. 7 d, described fault detector 17 sends fault-signal according to described alarm signal alarm constantly from t13.

Example four:

See also Fig. 8 a ~ 8d, described detecting unit 13 also can adopt 142 couples of described light-emitting diode D1 ~ D3 of shunt to carry out adjustment, when if described detecting unit 13 adopts second temperature sensor, the described second temperature sensor output OT2 is connected to described shunt input 142a, and adopt the triggering signal of second judging unit 146 as counter controller 16, shown in Fig. 8 a, when the temperature T led of light-emitting diode D1 ~ D3 changes shown in Fig. 8 b, the signal of the desirable output of the described second temperature sensor output OT2 is shown in the dotted line among Fig. 8 c, because the 142 pairs of the highest minimum level that will import of described shunt limit, so the signal of described shunt 142 actual inputs is shown in the solid line among Fig. 8, be that it begins from moment t14, the signal level of input 142a maintains its limit value, but not the level of output OT2 output, described shunt 142 produces corresponding High Speed Modulation signal to control described field effect transistor M1 according to the signal of input, (operation principle and the internal structure that are chip LTC3783 are all familiar to shunt 142 owing to those skilled in the art, no longer describe in detail at this), (described coherent signal can be the actual input value of described shunt 146 to described second determining device 146 according to the described shunt 142 inner signals relevant with described temperature signal simultaneously, also can be the flow-dividing control signal of its actual output etc.) judge the temperature that begins described light-emitting diode D1 ~ D3 constantly from t14 and surpass preset temperature value, therefore it exports second count signal, described counter controller 16 begins counting according to described second count signal, when its gate time surpasses preset value is that t15 is during the moment, the temperature that described second determining device 146 is judged described light-emitting diode D1 ~ D3 still surpasses preset temperature value, described fault detector 143 sends fault-signal, in addition, when if the temperature that described second determining device 146 is judged described light-emitting diode D1 ~ D3 surpasses preset temperature value, corresponding its can be exported clear 0 signal, and described counter controller 16 makes counting clear 0 according to clear 0 signal.

In addition, described control unit also can combine described pwm switch controller and control with the temperature to described luminous load with described shunt, and those skilled in the art can combine both according to above stated specification, so no longer repeat at this.

In sum, the utility model is by the detection to the luminous load temperature, can effectively reduce the power consumption of described luminous load by the effective value of shunting or regulate the drive current of the luminous load of flowing through, and then the luminous load temperature is effectively controlled, realization prolongs its useful life to the control of luminous load superheating phenomenon.

Claims

1. luminous load drive unit is characterized in that comprising:

Driver element, it is luminous to be used to drive one or more luminous loads;

Switch element is used to control the break-make that described driver element is connected with described one or more luminous loads;

Detecting unit is used to detect the temperature of described one or more luminous loads, and according to the temperature output relevant temperature signal of described one or more luminous loads;

Control unit, its input is connected with described detecting unit output, and its output is connected with described switch element, is used for producing according to the temperature signal of input the folding of the described switch element of corresponding control signals.

2. luminous load drive unit as claimed in claim 1 is characterized in that: described luminous load is light-emitting diode or organic electroluminescent LED.

3. luminous load drive unit as claimed in claim 2 is characterized in that: described driver element is for producing the current drives unit of drive current.

4. luminous load drive unit as claimed in claim 3 is characterized in that: described current drives unit comprises inductance, diode and electric capacity.

5. luminous load drive unit as claimed in claim 1 is characterized in that: described control unit comprises the pwm switch controller that produces the pulse width signal with corresponding duty ratio according to described temperature signal.

6. luminous load drive unit as claimed in claim 5 is characterized in that: described pwm switch controller is not less than the controller of default duty ratio for the minimum duty cycle of the pulse width signal of output.

7. luminous load drive unit as claimed in claim 5 is characterized in that described pwm switch controller comprises according to described pulse width signal and judges whether the temperature of described one or more luminous loads exceeds preset temperature value and export first determining device of first count signal when the temperature of described one or more luminous loads exceeds preset temperature value.

8. luminous load drive unit as claimed in claim 3 is characterized in that: described switch element also comprises one in order to described drive current is carried out first switch of flow-dividing control.

9. luminous load drive unit as claimed in claim 8 is characterized in that: described control unit comprises the shunt of flow-dividing control signal so that described drive current is shunted that is connected with described first switch and controls the described first switch folding according to described temperature signal generation.

10. luminous load drive unit as claimed in claim 9 is characterized in that described shunt comprises according to the inner signal relevant with described temperature signal of described shunt and judges whether the temperature of described one or more luminous loads exceeds preset temperature value is also exported second count signal when the temperature of described one or more luminous loads exceeds preset temperature value second determining device.

11. luminous load drive unit as claimed in claim 1 is characterized in that: described switch comprises one or more in field effect transistor, transistor and the relay.

12. luminous load drive unit as claimed in claim 1 is characterized in that: described detecting unit comprises first temperature sensor of exporting digital current potential temperature signal.

13. luminous load drive unit as claimed in claim 1 is characterized in that: described detecting unit comprises second temperature sensor of output analog temperature signal.

14. luminous load drive unit as claimed in claim 1 is characterized in that: described detecting unit comprises the three-temperature sensor of exporting digit period pulse temperature signal.

15. luminous load drive unit as claimed in claim 1, it is characterized in that also comprising the temperature signal that is used for according to described detecting unit output judges whether the temperature of described one or more luminous loads exceeds preset temperature value, and when the temperature of described luminous load exceeds preset temperature value, produce the 3rd determining device of the 3rd count signal.

16., it is characterized in that also comprising as claim 7 or 10 or 15 arbitrary described luminous load drive units:

Counter controller, be used for according to count signal control gate time to calculate the time that described one or more luminous load temperature continues to surpass preset temperature value, and when described gate time surpasses preset value the output alarm signal, wherein, described count signal comprises one or more in first count signal, second count signal and the 3rd count signal;

Fault detector is used for sending fault-signal according to described alarm signal.