CN203590552U

CN203590552U - Dimmable drive circuit used for LED MR16 spotlight

Info

Publication number: CN203590552U
Application number: CN201320708330.7U
Authority: CN
Inventors: 王兴华
Original assignee: Shenzhen Jiuzhou Optoelectronics Technology Co Ltd
Current assignee: Shenzhen Jiuzhou Optoelectronics Technology Co Ltd
Priority date: 2013-11-11
Filing date: 2013-11-11
Publication date: 2014-05-07
Anticipated expiration: 2023-11-11

Abstract

The utility model discloses a dimmable drive circuit used for an LED MR16 spotlight. The drive circuit comprises a rectification filter circuit, a voltage boosting and stabilizing circuit and a voltage reduction and constant current circuit, wherein the rectification filter circuit, the voltage boosting and stabilizing circuit and the voltage reduction and constant current circuit are successively connected. The drive circuit further comprises a phase control circuit. The input end of the rectification filter circuit is connected with a power supply. The output end of the voltage reduction and constant current circuit is connected with an LED. The phase control circuit comprises a rectification module, a voltage dividing module and a voltage regulating module. The rectification module is used for rectifying an input voltage and then outputting the voltage to the voltage dividing module. The voltage dividing module is used for dividing the input voltage and then outputting the voltage to the voltage regulating module. The voltage regulating module is used for outputting varied voltage to a voltage reduction and constant current module. The drive circuit can utilize independent devices and modules to achieve silicon controlled rectifier light modulation. The drive circuit is simple, practical, low in price and good in performance.

Description

For the tunable optical drive circuit of LED MR16 shot-light

Technical field

The utility model relates to LED technical field, relates more specifically to a kind of tunable optical drive circuit for LED MR16 shot-light.

Background technology

At present, LED light source, as green energy conservation light source, just progressively replaces conventional light source at lighting field.Meanwhile, the MR16 shot-light of LED also progressively replaces traditional MR16 shot-light.And traditional MR16 shot-light adopts controllable silicon and prime electronic transformer to drive light modulation more, based on this, LED need to realize with professional light modulation IC when capable of being matched with electronic transformer light modulation, and its price is comparatively expensive.

Therefore, be necessary to provide a kind of light modulation tunable optical drive circuit for LED MR16 shot-light that can address the aforementioned drawbacks.

Utility model content

The purpose of this utility model is to provide a kind of tunable optical drive circuit for LED MR16 shot-light to avoid light fixture flicker, improves light fixture serviceability and useful life.

To achieve these goals, the technical solution adopted in the utility model is: a kind of tunable optical drive circuit for LED MR16 shot-light is provided, it comprises connected successively current rectifying and wave filtering circuit, voltage boosting and stabilizing circuit and step-down constant-current circuit, wherein, the input termination input power of described current rectifying and wave filtering circuit, the output termination LED of described step-down constant-current circuit.Comprise in addition phase-control circuit, described phase-control circuit comprises rectification module, division module and voltage regulating module, described rectification module is for carrying out exporting to division module after rectification to input voltage, described division module is for inputted voltage is carried out exporting to voltage regulating module after dividing potential drop, and described voltage regulating module is used for the voltage of exporting change to step-down constant flow module.

Its further technical scheme is: described voltage regulating module comprises triode Q1, resistance R 2 and resistance R 4, the base stage of described triode Q1 is connected with the output of division module, its collector electrode is connected with voltage boosting and stabilizing circuit, its emitter is connected with one end of resistance R 4, the other end of described resistance R 4 is connected with one end of resistance R 2, the other end ground connection of described resistance R 2, the output that the connected node of described resistance R 4 and resistance R 2 is voltage regulating module, this output is connected to described step-down constant-current circuit.

Its further technical scheme is: described voltage regulating module also comprises capacitor C 7, and described capacitor C 7 is high-frequency filter capacitor, and its one end is connected to the connected node of resistance R 5 and resistance R 11, other end ground connection.

Its further technical scheme is: described division module comprises resistance R 5 and resistance R 11, described resistance R 5 and resistance R 11 are cascaded and one end is connected to the output of rectification module, other end ground connection, the base stage of described triode Q1 is connected to the connected node of resistance R 5 and resistance R 11.

Its further technical scheme is: described rectification module comprises diode D7, diode D8, resistance R 7 and capacitor C 6, the positive pole of described diode D7 and diode D8 is connected to the two ends of input power, its negative pole is all connected with one end of resistance R 7, the other end of described resistance R 7 is connected with resistance R 11, one end of described capacitor C 6 is connected to the connected node of resistance R 7 and resistance R 11, other end ground connection.

Compared with prior art, the tunable optical drive circuit for LED MR16 shot-light that the utility model provides has been set up phase-control circuit on the basis of existing drive circuit, phase circuit can change to adjust the output voltage of step-down constant-current circuit according to the controllable silicon phase place of input, thereby realizes the adjusting of LED brightness from 0-100%.The utility model can utilize cheap discrete device to realize controllable silicon light modulation, and it is simple and practical, low price and functional.

By following description also by reference to the accompanying drawings, it is more clear that the utility model will become, and these accompanying drawings are used for explaining embodiment of the present utility model.

Accompanying drawing explanation

Fig. 1 is the circuit diagram of the utility model for tunable optical drive circuit one embodiment of LED MR16 shot-light.

Embodiment

Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in embodiment is clearly and completely described, in accompanying drawing, similarly assembly label represents similar assembly.Obviously, below by the embodiment of description, be only the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment obtaining under creative work prerequisite, all belong to the scope of the utility model protection.

With reference to Fig. 1, Fig. 1 is the circuit diagram of the utility model for tunable optical drive circuit one embodiment of LED MR16 shot-light.In the present embodiment, described tunable optical drive circuit 10 comprises current rectifying and wave filtering circuit 11, voltage boosting and stabilizing circuit 12, step-down constant-

current circuit

13 and 14 4 parts of phase-control circuit.Wherein, current rectifying and wave filtering circuit 11, voltage boosting and stabilizing circuit 12 and step-down constant-current circuit 13 are connected successively, the input termination input power AC(of current rectifying and wave filtering circuit 11 is also the output of electronic transformer, its voltage is generally AC5V between 18V), this input voltage is raised to 24-30V interval after rectifying and wave-filtering, the output voltage that guarantees the IC of follow-up BUCK circuit is a stationary value and higher than output voltage, and BUCK circuit just can steady operation like this.The output termination LED of step-down constant-current circuit 13, its output voltage range is 9V-21V, LED can be used 3 to 7 strings.Input thyristor regulating light phase feeds back to BUCK constant current chip through phase-control circuit 14 and realizes electric current adjusting.Below in conjunction with Fig. 1, describe particular circuit configurations of the present utility model and operation principle in detail.

The current rectifying and wave filtering circuit 11 of the present embodiment comprises four rectifier diode D1～D4, electrochemical capacitor C1 and filter capacitor C5.Wherein, filter capacitor C5 is connected in parallel on the two ends of input power AC, for level and smooth input waveform; Four rectifier diode D1～D4 composition bridge heaps are to transfer interchange input to direct current output, and the positive pole of input power AC is connected on the connected node of D1 and D3, and the negative pole of input power AC is connected on the connected node of D2 and D4; Electrochemical capacitor C1 one end is connected on the connected node of electric capacity D3 and D4, other end ground connection, and it can provide filter action.

The voltage boosting and stabilizing circuit 12(BOOST level of the present embodiment) comprise master chip U1, power inductance L2, sustained diode 6, sampling resistor R1, R6 and output filter capacitor C4.Wherein, master chip U1 is the IC that boosts, and there is the benchmark output voltage of 1.25V its inside, and passing ratio divider resistance R1 and R6 raise output by the output voltage of BOOST level and be greater than the output of BUCK level, i.e. the pressure drop of LED series connection.Can guarantee that like this BUCK functional circuit normally works.The pin 1 of master chip U1 is grounding pin GND; Pin 2 is level enable pin EN, and high level is effective, and this pin can unsettledly not used; The switch pin SW that pin 3 is U1; The input power pin VIN that pin 4 is U1; Pin 5 is feedback pin FB.Power inductance L2 is connected between pin SW and pin VIN, and sustained diode 6 positive poles are connected with power inductance L2, negative pole exports step-down constant-current circuit 13 to, when the switch conduction of U1 inside, inductance L 2 stored energys, voltage reversal when switch turn-offs in inductance L 1, the negative pole output voltage of sustained diode 6 be VIN follow VL's and.The electrochemical capacitor C4 being connected in parallel in circuit is filter capacitor.

The step-down constant-current circuit 13(BUCK level of the present embodiment) comprise master chip U2, sustained diode 5, power inductance L1, sampling resistor R3 and patch capacitor C10.Master chip U2 has input voltage pin VIN, grounding pin GND, pin ADJ, pin LX and pin ISENSE, wherein, between pin VIN and pin ISENSE, meet sampling resistor R3, capacitance difference between two pins is 0.1V, so the pressure drop that output current is 0.1V is divided by the resistance of R3, thereby the switch that compares the pressure reduction of its two pins and the size of 0.1V control U2 inside by the comparator of IC inside turn-offs and conducting, realizes the object of step-down constant current.Sustained diode 5 is connected between pin VIN and pin LX and inductance L 1 is connected between pin LX and output, when the switch in U2 turn-offs, is that the energy of energy storage inductor L1 is outputed on load LED by loop.Patch capacitor C10 is connected between pin VIN and pin GND with filtering high frequency ripple.

The phase-control circuit 14 of the present embodiment comprises rectification module 141, division module 142 and voltage regulating module 143, wherein, described rectification module 141 is exported to division module 142 for input voltage is carried out after rectification, described division module 142 carries out exporting to voltage regulating module 143 after dividing potential drop for the voltage to inputted, described voltage regulating module 143 for the voltage of exporting change to step-down constant flow module 13.

Particularly, in the present embodiment, rectification module 141 comprises two rectifier diode D7 and D8, resistance R 7 and capacitor C 6; Division module 142 comprises divider resistance R5 and R11; Voltage regulating module 143 comprises triode Q1, divider resistance R2 and R4 and filtering high frequency capacitance C7.In rectification module 141, the positive pole of rectifier diode D7 and diode D8 is connected to the two ends of input power AC, its negative pole is all connected with one end of resistance R 7, the other end of resistance R 7 is connected with resistance R 11, and one end of capacitor C 6 is connected to the connected node of resistance R 7 and resistance R 11, the other end is connected to the earth terminal of U2.In division module 142, divider resistance R5 and resistance R 11 are cascaded and one end is connected to one end (output of rectification module 141) of resistance R 7, and the other end is connected to the earth terminal of U2.In voltage regulating module 143, the base stage of triode Q1 is connected to the connected node of resistance R 5 and resistance R 11, collector electrode is connected with voltage boosting and stabilizing circuit 12, its emitter is connected with one end of resistance R 4, the other end of described resistance R 4 is connected with one end of resistance R 2, the earth terminal of another termination U2 of described resistance R 2, the connected node of described resistance R 4 and resistance R 2 is the output of voltage regulating module 143, this output is connected to the ADJ pin of U2 in described step-down constant-current circuit 13.

In foregoing circuit, the controllable silicon phase place variation of circuit input end realizes average current detection by detecting diode D7, D8, R7 and C6, R5, R11 is for dividing potential drop and reduce the velocity of discharge, and voltage changes with input phase, its voltage is for controlling the base stage of penetrating with circuit triode Q1, changes voltage by Q1, launch U2 very the voltage of variation is provided with phase place, realize electric current and regulate, and then realize the brightness regulation of LED.U2 pin voltage range 0.2V～1.2V, no-output when being less than 0.2V, LED is bad, and when magnitude of voltage changes between 0.2V～1.2V, LED realizes the variation of brightness from 0-100%, while being greater than 1.2V, LED maintains 100% brightness, thereby realize phase place, change, LED brightness changes.

As mentioned above, the tunable optical drive circuit for LED MR16 shot-light that the utility model provides has been set up phase-control circuit on the basis of existing drive circuit, phase circuit can change to adjust the output voltage of step-down constant-current circuit according to the controllable silicon phase place of input, thereby realizes the adjusting of LED brightness from 0-100%.The utility model can utilize cheap discrete device to realize controllable silicon light modulation, and it is simple and practical, low price and functional.

In conjunction with most preferred embodiment, the utility model is described above, but the utility model is not limited to the embodiment of above announcement, and should contains the various modifications of carrying out according to essence of the present utility model, equivalent combinations.

Claims

1. the tunable optical drive circuit for LED MR16 shot-light, comprise connected successively current rectifying and wave filtering circuit (11), voltage boosting and stabilizing circuit (12) and step-down constant-current circuit (13), wherein, the input termination input power (AC) of described current rectifying and wave filtering circuit (11), the output termination LED of described step-down constant-current circuit (13), it is characterized in that: also comprise phase-control circuit (14), described phase-control circuit (14) comprises rectification module (141), division module (142) and voltage regulating module (143), described rectification module (141) is exported to division module (142) for input voltage is carried out after rectification, described division module (142) carries out exporting to voltage regulating module (143) after dividing potential drop for the voltage to inputted, described voltage regulating module (143) for the voltage of exporting change to step-down constant flow module (13).

2. the tunable optical drive circuit for LED MR16 shot-light as claimed in claim 1, it is characterized in that: described voltage regulating module (143) comprises triode (Q1), resistance (R2) and resistance (R4), the base stage of described triode (Q1) is connected with the output of division module (142), its collector electrode is connected with voltage boosting and stabilizing circuit (12), its emitter is connected with the one end of resistance (R4), the other end of described resistance (R4) is connected with one end of resistance (R2), the other end ground connection of described resistance (R2), the connected node of described resistance (R4) and resistance (R2) is the output of voltage regulating module (143), this output is connected to described step-down constant-current circuit (13).

3. the tunable optical drive circuit for LED MR16 shot-light as claimed in claim 2, it is characterized in that: described voltage regulating module (143) also comprises electric capacity (C7), described electric capacity (C7) is high-frequency filter capacitor, its one end is connected to the connected node of resistance (R5) and resistance (R11), other end ground connection.

4. as claimed in claim 2 or claim 3 for the tunable optical drive circuit of LED MR16 shot-light, it is characterized in that: described division module (142) comprises resistance (R5) and resistance (R11), described resistance (R5) and resistance (R11) are cascaded and one end is connected to the output of rectification module (141), other end ground connection, the base stage of described triode (Q1) is connected to the connected node of resistance (R5) and resistance (R11).

5. the tunable optical drive circuit for LED MR16 shot-light as claimed in claim 4, it is characterized in that: described rectification module (141) comprises diode (D7), diode (D8), resistance (R7) and electric capacity (C6), the positive pole of described diode (D7) and diode (D8) is connected to the two ends of input power (AC), its negative pole is all connected with one end of resistance (R7), the other end of described resistance (R7) is connected with resistance (R11), one end of described electric capacity (C6) is connected to the connected node of resistance (R7) and resistance (R11), other end ground connection.