CN201680198U

CN201680198U - LED lamp capable of changing color temperature

Info

Publication number: CN201680198U
Application number: CN2010201875826U
Authority: CN
Inventors: 吴昭莉
Original assignee: Zhejiang Jinzhong Mechanical & Electrical Technology Co Ltd
Current assignee: Zhejiang Jinzhong Mechanical & Electrical Technology Co Ltd
Priority date: 2010-05-11
Filing date: 2010-05-11
Publication date: 2010-12-22
Anticipated expiration: 2020-05-11

Abstract

An LED lamp capable of changing color temperature comprises a filtering rectifier circuit (1), a switch control circuit (2), a pulse transformer (T), a constant current driver circuit (3), a bistable circuit (4), two switch triodes (Q2 and Q3) and two groups of LED lamp string. The LED lamp string in one group includes high color temperature lamps, and the LED lamp string in the other group includes low color temperature lamps, the lamp string in each group is respectively connected with a switch triode in series and is connected with the output end of the constant current driver circuit, the bases of the two switch triodes are respectively connected with the two output ends of the bistable circuit. A power supply input end is connected with an AC power supply, one output end of the bistable circuit is high level and the other output end of the bistable circuit is low level, so one LED lamp string is on and the other LED lamp string is off. When the AC power supply is turned off and on for once, the bistable circuit is inverted, then the LED lamp string already turned on is turned off and the other LED lamp string is turned on, so as to change the color temperature of the LED lamps, and the transformation can be continuously and repeatedly carried out.

Description

Can change the LED lamp of colour temperature

Technical field

The utility model relates to a kind of structure of LED lamp, a kind of LED lamp that can change colour temperature.

Background technology

Because incandescent lamp has shortcomings such as energy consumption height, life-span weak point, all there are the relevant policies of superseded incandescent lamp countries in the world.The LED light fixture has energy-conservation, as to subtract carbon advantage, is new illuminating product of future generation.Illuminating LED lamp generally comprises power unit and one group of LED lamp string of being made up of filter rectifier, ON-OFF control circuit, pulse transformer, constant-current drive circuit.The colour temperature of this class LED lamp can not be regulated.

Summary of the invention

The utility model is intended to propose a kind of structure that can change the LED lamp of colour temperature.

This LED lamp that can change colour temperature comprises filter rectifier, ON-OFF control circuit, pulse transformer, constant-current drive circuit, bistable circuit, two switch triodes and two groups of LED lamp strings.Wherein one group of LED lamp string is a high color temperature lamp, another group LED lamp string is low color temperature lamp, every group of LED lamp string respectively with the output of receiving constant-current drive circuit after a switch triode is connected, the base stage of two switch triodes is joined with two outputs of bistable circuit respectively.

After the power input of this LED lamp that can change colour temperature and AC power are connected, an output of bistable circuit is a high level, the switch triode conducting that is attached thereto, corresponding one group of LED lamp cross luma, another output of bistable circuit is a low level, the switch triode that is attached thereto ends, and this group LED lamp string does not work accordingly.AC power close-is opened once, the bistable circuit counter-rotating, high level output originally becomes low level, low level output originally becomes high level, originally one group of LED lamp string lighting is gone out, and the one group of LED lamp cross luma that did not work originally, thereby can change the colour temperature of LED lamp, and can constantly repeat above-mentioned conversion.

Description of drawings

Fig. 1 is the schematic diagram of existing LED lamp;

Fig. 2 is the schematic diagram of the LED lamp that can change colour temperature that the utility model proposes.

The specific embodiment

As shown in Figure 1, existing illuminating LED lamp generally comprises power unit and the one group of LED lamp string LED0 that is made up of filter rectifier 1, ON-OFF control circuit 2, pulse transformer T, constant-current drive circuit 3.This circuit is the led driver of a typical inverse-excitation type isolation structure.Wherein filter rectifier 1 comprises wave filter N0, rectifier DB1, the first filter capacitor C1.ON-OFF control circuit 2 comprises pulse width controller N1, FET Q1, the second commutation diode D2 and the second filter capacitor C3.Pulse transformer T comprises primary coil L1, secondary coil L2 and the first ancillary coil L3.Constant-current drive circuit 3 comprises constant-current controller N2, the 3rd commutation diode D3, the 3rd filter capacitor C5, divider resistance R10 and sample resistance R11.The input of wave filter N0 joins by a K switch and AC power, and the ac input end of the output of wave filter and rectifier DB1 joins.The first filter capacitor C1 is connected between the positive output end and negative output terminal of rectifier.The end of the primary coil L1 of the positive output end of rectifier and pulse transformer joins.The negative output terminal of rectifier by FET Q1 source electrode and the other end of the primary coil L1 of drain electrode and pulse transformer join.The control end DIV of pulse width controller N1 links to each other with the grid of FET Q1, the opening and closing of control FET, thus in L1, produce a dither electric current, through pulse transformer T coupling, in secondary coil L2, obtain corresponding pulse voltage.The positive pole of the output of secondary coil L2 and the 3rd commutation diode D3 joins, the negative pole of the 3rd commutation diode D3 is received the anode of LED lamp string LED0, the 3rd filter capacitor C5 is connected between another output of the negative pole of the 3rd commutation diode D3 and secondary coil L2, and the negative terminal of LED lamp string LED0 and another output of secondary coil L2 join.Pulse voltage among secondary coil L2 output dc voltage after D3 rectification, C5 filtering is given LED0.Divider resistance R10 and the two ends of receiving LED0 after sample resistance R11 connects.Divider resistance R10 links to each other with the signal input part of constant-current controller N2 with the tie point of sample resistance R11.The output of constant-current controller N2 is connected to a diode QP2 in the photo-coupler, is connected to a triode QP1 in the photo-coupler between the light modulation end DIM of pulse width controller N1 and the ground.The variation of the voltage on the LED0 (electric current) feeds back to pulse width controller N1 by sample resistance R11, constant-current controller N2 and photo-coupler QP1, QP2, is used for adjusting the dutycycle of the conduction and cut-off of FET.Pulse width controller N1 is by the first ancillary coil L3 supply of electrical energy.Diode D1 is a fly-wheel diode among the figure, when FET Q1 ends, by D1 the energy of inductance winding is discharged to load.

This LED lamp that can change colour temperature that the utility model proposes is to have increased a bistable circuit and two switch triodes on circuit shown in Figure 1.Its principle as shown in Figure 2.This LED lamp that can change colour temperature comprises filter rectifier 1, ON-OFF control circuit 2, pulse transformer T, constant-current drive circuit 3, LED lamp string, bistable circuit 4 and the first switch triode Q2, second switch triode Q3.Wherein LED lamp string is two groups of LED1, LED2, and one group is high color temperature lamp, and another group is low color temperature lamp.LED1 and the output of receiving constant-current drive circuit after the first switch triode Q2 connects, just the positive output end of the anode of LED1 and constant-current drive circuit joins, the negative terminal of LED1 and the colelctor electrode of Q2 join, and the emitter stage of Q2 and the negative output terminal of constant-current drive circuit join.LED2 and the output of receiving constant-current drive circuit after second switch triode Q3 connects, just the positive output end of the anode of LED2 and constant-current drive circuit joins, the negative terminal of LED2 and the colelctor electrode of Q3 join, and the emitter stage of Q3 and the negative output terminal of constant-current drive circuit join.Bistable circuit 4 comprises flip and flop generator N3, the 4th commutation diode D4, filter resistance R4 and the 4th filter capacitor C7.Pulse transformer T goes up increases by one group of second ancillary coil L4.The end of the second ancillary coil L4 and the positive pole of the 4th commutation diode D4 join, the negative pole of the 4th commutation diode D4 joins by the positive pole of filter resistance R4 and the 4th filter capacitor C7, and the negative pole of the other end of the second ancillary coil L4 and the 4th filter capacitor C7 joins.The power end VCC of flip and flop generator N3 and the positive pole of the 4th filter capacitor C7 join.The trigger end CP of the negative pole of the 4th commutation diode D4 and flip and flop generator N3 joins.The negative pole of the 4th commutation diode D4 is that trigger end CP by current-limiting resistance R6 and flip and flop generator N3 joins among the figure, and C9 is an integrating capacitor, and C9 makes the CP terminal voltage stable.Output O0 of flip and flop generator and the base stage of the first switch triode Q2 are joined by a resistance R 8, and the base stage of another output O1 of flip and flop generator and second switch triode Q3 is joined by another resistance R 9.C6 also is a filter capacitor among the figure, and it and R4, C7 form π type RC filter circuit, and the operating voltage of bistable circuit is provided.

The course of work of this LED lamp that can change colour temperature is as follows: establishing LED1 is high color temperature lamp, and LED2 is low color temperature lamp, and for example high colour temperature is the white of 6000K, and low colour temperature is the warm colour of 3000K.After power input and civil power were connected, the O0 output of flip and flop generator N3 was a high level, the switch triode Q2 conducting that it is controlled, LED1 is bright, sends out colour temperature light high, and the O1 output of flip and flop generator is a low level, the switch triode Q3 that it is controlled ends, and LED2 does not work.K switch close-is opened once, the trigger end CP of flip and flop generator N3 obtains a new triggering signal, the circuit counter-rotating, high level output O0 originally becomes low level, low level output 01 originally becomes high level, originally the LED1 that lighted is gone out, and the LED2 that did not work originally is bright, sends low colour temperature light.Repeatedly K switch is closed an ON operation, can change the colour temperature of LED lamp repeatedly.The K switch short time, capacitor C 7 can make flip and flop generator keep one period working time, thereby can carry out the conversion of the different-colour of LED lamp when disconnecting.When the electric weight in K switch disconnection long period, the capacitor C 7 was not enough to keep flip and flop generator work, after K connected again, circuit will be started working from original state again.

Wave filter N0, rectifier DB1, pulse width controller N1, constant-current controller N2 and flip and flop generator N3 in this LED lamp that can change colour temperature all can adopt known model commonly used.

The utility model can be applicable to various indoor lamp lighting devices such as bulb class, fluorescent tube class, spotlight, strip light, following illuminator, ornament lamp, Recessed light class.

Claims

1. LED lamp that can change colour temperature, comprise filter rectifier (1), ON-OFF control circuit (2), pulse transformer (T), constant-current drive circuit (3) and LED lamp string, it is characterized in that this LED lamp that can change colour temperature also comprises bistable circuit (4) and first switch triode (Q2), second switch triode (Q3), described LED lamp string is two groups of (LED1, LED2), wherein one group is high color temperature lamp, another group is low color temperature lamp, every group of LED lamp string respectively with the output of receiving constant-current drive circuit after a switch triode is connected, the base stage of two switch triodes is joined with two outputs of bistable circuit respectively.

2. the LED lamp that can change colour temperature as claimed in claim 1, it is characterized in that described bistable circuit (4) comprises flip and flop generator (N3), the 4th commutation diode (D4), filter resistance (R4) and the 4th filter capacitor (C7), one group of second ancillary coil (L4) arranged on the described pulse transformer (T), the positive pole of one end of second ancillary coil (L4) and the 4th commutation diode (D4) joins, the negative pole of the 4th commutation diode (D4) joins by the positive pole of filter resistance (R4) with the 4th filter capacitor (C7), the power end (VCC) of flip and flop generator (N3) joins with the positive pole of the 4th filter capacitor (C7), the trigger end (CP) of the negative pole of the 4th commutation diode (D4) and flip and flop generator (N3) joins, an output (O0) of flip and flop generator joins by a resistance (R8) with the base stage of first switch triode (Q2), and another output (O1) of flip and flop generator joins by another resistance (R9) with the base stage of second switch triode (Q3).