CN202261959U - Color temperature adjusting driver of light-emitting diode (LED) lamp - Google Patents

Abstract

The utility model discloses a driver for adjusting the color temperature of an LED lamp. Through a time-division multiplexing control module, the control signals of light source modules corresponding to high and low color temperatures are divided in time, so that at most one of them is at a high level at any moment. The power output module can output a driving voltage or current at most to drive the corresponding light source module to emit light. In this way, the power provided by the power converter is distributed to different branches in different time periods in turn, and there is no power supply caused by the superposition of power peaks. Converter overload problem, so power converter power configuration can be reduced to one-half of the prior art. The reduction of the power of the power converter means that its size and weight are reduced, thus saving the cost of the LED lamp.

Description

A LED lamp color temperature adjustment driver

technical field

The utility model belongs to the technical field of LED lamp control, and more specifically relates to a driver for adjusting the color temperature of an LED lamp.

Background technique

As a high-efficiency new light source, LED lights are widely used in commercial, industrial, road, advertising light boxes and other fields due to their advantages of long life, low energy consumption, energy saving and environmental protection.

With the wide application of LED lights, people have higher and higher requirements for LED lights, forming a variety of control methods from single brightness adjustment to color temperature adjustment. In order not to affect the color temperature drift of the LED, most of the LED lights that adjust the brightness and color temperature adopt the PWM (Pulse Width Modulation, pulse width modulation) method.

In order to maintain the consistency of power, color temperature LED lights usually use the power of the single color temperature light source module as the maximum power of the LED light. When two color temperature light source modules emit light at the same time, the maximum power does not exceed the single color temperature light source module. Power, so the two color temperature light source modules emit light at the same time, and when the brightness is maximum, they both work at half power.

At present, when the color temperature LED lights are adjusted by PWM, there is a problem of power peak superposition. In order to avoid power overload, the power converter of the color temperature LED lamp is configured based on the total power of all light source modules. However, the maximum actual power consumption of the color-temperature LED lamp is only about half of the output power of the power converter, which will cause a waste of power for the configuration. Relatively high defects.

Contents of the invention

The purpose of the utility model is to overcome the deficiencies of the prior art, and provide a driver for adjusting the color temperature of the LED lamp, which makes the output power of the power converter equal to the maximum value of the actual power consumption of the LED lamp with the color temperature.

In order to achieve the above purpose, the utility model LED lamp color temperature adjustment driver is characterized in that it includes:

A time-division multiplexing control module. The time-division multiplexing control module has two registers and a communication interface. The two registers are used to store the switch-on time of the high color temperature and low color temperature light source modules respectively. The communication interface is connected to the color temperature adjustment control circuit. The on-time data of the high color temperature and low color temperature light source modules from the color temperature adjustment control circuit is used to adjust and update the on time of the high color temperature and low color temperature light source modules stored in the two registers to realize the adjustment of the color temperature of the LED lamp ; There are two light source module control signal outputs, corresponding to the control of high color temperature and low color temperature respectively;

In the control cycle, first change the control signal of the light source module corresponding to the high color temperature or low color temperature from low level to high level, and maintain the corresponding on-time, and then, the light source module corresponding to the high color temperature or low color temperature After the control signal becomes low level, the control signal of the light source module corresponding to the low color temperature or high color temperature is changed from low level to high level, and the corresponding on-time is maintained.

A power output module, when the control signal of the light source module corresponding to a certain color temperature is at a high level, it outputs a driving voltage or current to drive the corresponding light source module to emit light;

Both the time-division multiplexing control module and the power output module are connected to the power converter, and the power converter provides DC power for the time-division multiplexing control module and the power output module.

The utility model purpose is achieved in that:

The LED lamp color temperature adjustment driver of the utility model divides the light source module control signals corresponding to the high and low color temperatures in time through the time-division multiplexing control module, so that at any one time, at most one of them is at high level, and the power output module is at most one way Output driving voltage or current to drive the corresponding light source module to emit light, so that the power provided by the power converter is distributed to different branches in different time periods in sequence, and there is no problem of power overload caused by power peak superposition, so The output power configuration of the power converter can be reduced to one-half of the prior art. The reduction of the power of the power converter means that its size and weight are reduced, thus saving the cost of the LED lamp.

Description of drawings

Fig. 1 is a schematic diagram of a specific embodiment of the driver for adjusting the color temperature of the LED lamp of the present invention;

Fig. 2 is a schematic diagram of a specific embodiment of the time division multiplexing control module shown in Fig. 1;

Fig. 3 is a functional block diagram of a specific embodiment of the power output module shown in Fig. 1;

Fig. 4 is a functional block diagram of another specific embodiment of the power output module shown in Fig. 1;

Fig. 5 is a functional block diagram of another specific embodiment of the power output module shown in Fig. 1;

Fig. 6 is a functional block diagram of another specific embodiment of the power output module shown in Fig. 1;

Fig. 7 is a functional block diagram of another specific embodiment of the power output module shown in Fig. 1;

FIG. 8 is a time sequence diagram of specific examples of control signals of the light source module in different color temperature states.

Detailed ways

The specific embodiments of the present invention will be described below in conjunction with the accompanying drawings, so that those skilled in the art can better understand the present invention. It should be noted that in the following description, when detailed descriptions of known functions and designs may dilute the main content of the present invention, these descriptions will be ignored here.

Fig. 1 is a principle diagram of a specific embodiment of the driver for adjusting the color temperature of the LED lamp of the present invention.

In this embodiment, as shown in FIG. 1 , the LED lamp color temperature adjustment driver 2 includes a time division multiplexing control module 201 and a power output module 202 .

The time-division multiplexing control module 201 has two light source module control signals PMW1 and PMW2 output, corresponding to the control of high color temperature and low color temperature respectively.

The power output module 202 outputs a driving voltage or current to drive the corresponding light source module to emit light when the control signal of the light source module corresponding to high color temperature or low color temperature is at a high level. That is, when the light source module control signal PMW1 is at a high level, it outputs a driving voltage or current to drive the high color temperature light source module to emit light; when the light source module control signal PMW2 is at a high level, it outputs a driving voltage or current to drive a low color temperature light source module. Group glow.

Both the time-division multiplexing control module 201 and the power output module 202 are connected to the power converter 1 , and the power converter 1 provides DC power for the time-division multiplexing control module 201 and the power output module 202 . In this embodiment, power converter 1 includes AC-DC converter 101 and plug 102; Connect to the grid for AC power. The AC-DC converter 101 converts the alternating current obtained from the grid into direct current, and provides it to the time-division multiplexing control module 201 and the power output module 202 . The structure and principle of the power converter belong to the prior art and will not be repeated here.

Fig. 2 is a schematic diagram of a specific embodiment of the time division multiplexing control module shown in Fig. 1 .

In the present embodiment, as shown in Figure 2, time division multiplexing control module 201 comprises a microprocessing unit (MCU) 2011 and DC-DC converter 2012; There are two registers R1, R2 and communication interface in the microprocessing unit 2011 , in this embodiment, the communication interface is a DALI interface (Digital Addressable Lighting Interface, Digital Addressable Lighting Interface).

The two registers R1 and R2 are respectively used to store the switch-on time of the high color temperature and low color temperature light source modules, the communication interface is connected to the color temperature adjustment control circuit, and receives the high color temperature and low color temperature light source module switch-on from the color temperature adjustment control circuit The time data DATA is used to adjust and update the switch-on time of the high color temperature and low color temperature light source modules stored in the two registers R1 and R2, so as to realize the color temperature adjustment of the LED lamp.

Because in this embodiment, the power converter 1 only outputs one direct current Vdd, because it needs to provide power to the power output module 202 at the same time, its voltage value is relatively high, so it needs to be stepped down to meet the needs of the microprocessing unit 2011. For power requirements, the DC-DC converter 2012 steps down the direct current Vdd, and then outputs it as the power of the micro-processing unit 2011 .

Fig. 3 is a functional block diagram of a specific implementation manner of the power output module shown in Fig. 1 .

In this embodiment, as shown in FIG. 3 , the power output module 202 includes two constant current drivers Q1 and Q2, both of which have PWM dimming interfaces. When the control signal of a certain light source module is When the level is high, the constant current driver connected to it has a driving current output, and drives the corresponding light source module to emit light. In addition, the constant current driver is a constant current source with open circuit protection.

In the control period T, firstly, the light source module control signal PWM1 corresponding to a color temperature, in this embodiment, a high color temperature is changed from low level to high level, and the corresponding on-time t1 is maintained, and then, the high color temperature corresponds to After the light source module control signal PWM1 becomes low level, another light source module control signal PWM2 corresponding to low color temperature in this embodiment is changed from low level to high level, and the corresponding connection is maintained. time t2.

As shown in Figure 1, the time division multiplexing control module 201 outputs two high-level non-overlapping light source module control signals PWM1 and PWM2 signals. When the light source module control signal PWM1 is high level, the constant current driver Q1 outputs a driving current to drive The high color temperature light source module emits light; when the light source module control signal PWM2 is at a high level, the constant current driver Q2 outputs a driving current to drive the low color temperature light source module to emit light; thus realizing the power transmission power at different time periods within the control cycle T, through the constant current The driver Q1 is distributed to the high color temperature light source module, and is distributed to the low color temperature light source module via the constant current driver Q2.

By setting the on-times t1 and t2 of the light source modules with high color temperature and low color temperature, and controlling the high-level time of the control signals PWM1 and PWM2 of the light source modules, the color temperature of the LED lamp can be adjusted.

Fig. 4 is a functional block diagram of another embodiment of the power output module shown in Fig. 1 .

In this embodiment, as shown in FIG. 4 , the time-division multiplexing control module 201 outputs two high-level non-overlapping light source module control signals PWM1 and PWM2, and each light source module control signal controls two sets of constant current drivers. When the light source module control signal PWM1 is at a high level, the constant current drivers Q1A and Q1B have outputs, and the high color temperature light source modules 1A and 1B emit light; when the light source module control signal PWM2 is at a high level, the constant current drivers Q2A and Q2B have outputs, The low color temperature light source modules 2A and 2B emit light, so that the output power of the power converter is distributed to the high color temperature light source modules 1A and 1B via the constant current drivers Q1A and Q1B at different time periods within the control cycle T, and then distributed to the high color temperature light source modules 1A and 1B via the constant current driver. Q2A and Q2B are allocated to the low color temperature light source modules 2A and 2B, and the color temperature adjustment of the LED lamp is realized by setting the high level time of the two light source module control signals PWM1 and PWM2.

In this embodiment, a LED lamp with a rated power of 40W is a panel lamp with color temperature. The light source part consists of two groups of 14 strings of 24 parallel high color temperature single 0.06W light source modules 1A and 1B and two groups of 14 strings of 24 parallel low color temperature. The single 0.06W light source modules 2A and 2B are composed of four groups of light source modules connected by independent loops.

Fig. 5 is a functional block diagram of another embodiment of the power output module shown in Fig. 1 .

In this embodiment, as shown in Figure 5, the power output module 202 includes a constant current driver 2021 and two switch tubes K1, K2, the constant current driver 202 is a constant current source with open circuit protection, and the two switch tubes K1 , K2 are respectively connected in series with the light source modules D1 and D2 corresponding to the respective color temperatures. In this embodiment, the light source modules D1 and D2 are respectively a high color temperature light source module and a low color temperature light source module, and then both are connected to the constant current driver 2021 The output terminals of the two light source module control signals PWM1 and PWM2 are respectively connected to the control terminals of the switch tubes K1 and K2 corresponding to the color temperature. When the control signal of a certain light source module is at high level, the switch tube connected to it On, the constant current driver has an output to drive the corresponding light source module to emit light through the switch tube. In this way, compared with the power output modules shown in Figs. 3 and 4, only one constant current driver is needed, so the cost is greatly reduced.

Fig. 6 is a functional block diagram of another embodiment of the power output module shown in Fig. 1 .

In this embodiment, as shown in FIG. 6 , the power output module 202 only includes two switch tubes K1 and K2, and the two switch tubes K1 and K2 are respectively connected in series with the light source modules D1 and D2 corresponding to their respective color temperatures, and then directly Connect to the output terminals Vdd and GND of the power converter, and the control signals PWM1 and PWM2 of the two light source modules are respectively connected to the control terminals of the switch tubes K1 and K2 corresponding to the color temperature. When the control signal of a certain light source module is at high level, The switch tube connected to it is turned on, and the output of the power converter drives the corresponding light source module to emit light through the switch tube.

In this manner, compared with the power output module shown in FIG. 5 , only two switch tubes K1 and K2 are needed, so that the cost is further reduced.

Fig. 7 is a functional block diagram of another specific embodiment of the power output module shown in Fig. 1 .

In this embodiment, as shown in FIG. 7, the power output module 202 includes an AC-DC constant current driver 2021 and two switch tubes K1, K2; the AC-DC constant current driver 202 is a constant current source with open circuit protection , which puts the AC-DC conversion module in the constant current driver shown in Figure 5, and directly obtains electric energy from the grid, essentially combining the power converter 1 in Figure 5 with the constant current driver. The other working processes and principles are the same as those of the LED light adjusting driver in Fig. 5, and will not be repeated here.

FIG. 8 is a time sequence diagram of specific examples of control signals of the light source module in different color temperature states.

In this embodiment, as shown in Figure 5, (a) to (d) are the control signals of the light source module in different color temperature states, that is, medium color temperature high brightness, medium color temperature half brightness, high color temperature high brightness, high color temperature half brightness Bright) Lower time sequence diagram of the light source module control signals PWM1 and PWM2 output by the time-division multiplexing control module 202 . The on-time t1 corresponds to the high-level time of the control signal PWM1 of the light source module, the on-time t2 corresponds to the high-level time of the control signal PWM2 of the light source module, and the control period is T=4ms.

Figure 8(a) shows the timing diagram of the time division multiplexing module in the medium color temperature high brightness state, t1=2ms, t2=2ms, t1+t2=T, the output power of the constant current driver is about 40W, the high color temperature light source module and the low color temperature The light source modules all work at half power.

Figure 8(b) shows the timing diagram of the time-division multiplexing module in the medium color temperature half-brightness state, t1=1ms, t2=1ms, t1+t2=T/2, the output power of the constant current driver is about 20W, the high color temperature light source module and Low color temperature light source modules all work at 1/4 power.

Figure 8(c) shows the timing diagram of the time division multiplexing module in the high color temperature and high brightness state, t1=4ms, t2=0ms, t1+t2=T, the output power of the constant current driver is about 40W, and the high color temperature light source module works at full power , the low color temperature light source module does not work;

Figure 8(d) shows the timing diagram of the time division multiplexing module in the high color temperature half-bright state, t1=2ms, t2=0ms, t1+t2=T/2, the output power of the constant current driver is about 20W, and the high color temperature light source module Working at half power, the low color temperature light source module does not work.

Four examples of color temperature adjustment are given above. Other color temperature states can be adjusted by adjusting the high-level time of the light source module control signals PWM1 and PWM2, that is, changing the on-time t1 and t2 to control the high color temperature light source module and low color temperature. The light source module can mix colors into different color temperature states. For the adjustment of a certain color temperature, in the case of keeping the brightness unchanged, change the on-time t1, t2, but the sum of t1, t2 maintains a constant value.

At the same time, it can be seen from Figure 8 that as long as the maximum power of the LED lamp is determined, the maximum power of each light source module is also determined, which is the same as the maximum power of the LED lamp. The maximum brightness of each color temperature display should be the same, otherwise when the color temperature is adjusted, the brightness will change.

In this embodiment, if the traditional driving method is adopted, the control signals PWM1 and PWM2 of the light source module will both be at high level, and the power peaks will be superimposed. At this time, an 80W power converter needs to be configured. And adopt the scheme of the utility model, the power of the power converter is 1/2 of the traditional scheme. In addition, since there will be no superposition of power peaks, the output power is relatively stable.

In this embodiment, as shown in FIG. 5 , within the control time T, the high levels of the control signals PWM1 and PWM2 of each light source module are evenly spaced, which can further maintain the stability of the output power of the power converter 1 .

The light source module control signal PWM signal described in the utility model adopts positive logic, and the high level is effective to control the output of the power output module to drive the light source module with high color temperature and low color temperature to emit light. The utility model can also adopt negative Logic, or positive and negative logic mixed way, to achieve output power peak complementary control.

Although the illustrative specific implementation of the present invention has been described above, so that those skilled in the art can understand the utility model, it should be clear that the utility model is not limited to the scope of the specific implementation, and those of ordinary skill in the art Speaking, as long as the various changes are within the spirit and scope of the utility model defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the utility model are included in the protection list.

Claims (7)

1. A driver for adjusting the color temperature of an LED lamp, characterized in that it comprises: A time-division multiplexing control module. The time-division multiplexing control module has two registers and a communication interface. The two registers are respectively used to store the switch-on time of the high color temperature and low color temperature light source modules. The communication interface is connected to the color temperature adjustment control circuit. Receive the on-time data of the high color temperature and low color temperature light source modules from the color temperature adjustment control circuit, and use it to adjust and update the on-time of the high color temperature and low color temperature light source modules stored in the two registers, so as to realize the adjustment of the color temperature of the LED lamp. Adjustment; there are two light source module control signal outputs, corresponding to the control of high color temperature and low color temperature respectively; In the control cycle, first change the control signal of the light source module corresponding to the high color temperature or low color temperature from low level to high level, and maintain the corresponding on-time, and then, the light source module corresponding to the high color temperature or low color temperature After the control signal becomes low level, change the control signal of the light source module corresponding to the low color temperature or high color temperature from low level to high level, and maintain the corresponding on-time; A power output module, when the control signal of the light source module corresponding to a certain color temperature is at a high level, it outputs a driving voltage or current to drive the corresponding light source module to emit light; Both the time-division multiplexing control module and the power output module are connected to the power converter, and the power converter provides DC power for the time-division multiplexing control module and the power output module. 2. The LED lamp color temperature adjustment driver according to claim 1, wherein the communication interface is a digitally addressable lighting interface. 3. The LED lamp color temperature adjustment driver according to claim 1, wherein the power output module includes two constant current drivers, and the constant current driver is a constant current power supply with open circuit protection; when a certain light source module When the group control signal is at a high level, the constant current driver connected to it has a driving current output, and drives the corresponding light source module to emit light. 4. The LED lamp color temperature adjustment driver according to claim 1, wherein the power output module includes a constant current driver and two switch tubes; The constant current driver is a constant current power supply with open circuit protection. The two switch tubes are connected in series with the light source modules corresponding to their respective color temperatures, and then both are connected to the output terminals of the constant current driver. The control signals of the two light source modules are respectively connected to the corresponding At the control end of the color temperature switch tube, when the control signal of a certain light source module is at high level, the switch tube connected to it is turned on, and the output of the constant current driver drives the corresponding light source module to emit light through the switch tube. the 5. The driver for adjusting the color temperature of an LED lamp according to claim 1, wherein the adjustment of the color temperature is as follows: changing the on-time of the high color temperature and low color temperature light source modules, but the high color temperature and low color temperature light source modules The sum of on time maintains a constant value. 6 . The LED lamp color temperature adjustment driver according to claim 1 , wherein within the control time T, the high levels of the light source module control signals corresponding to the high color temperature and low color temperature are evenly spaced. 7. The driver for adjusting the color temperature of an LED lamp according to claim 1, wherein the power output module only includes two switch tubes, and the two switch tubes are respectively connected in series with the light source modules corresponding to their respective color temperatures, and then both are directly connected to each other. Connect to the output terminal of the power converter, and the control signals of the two light source modules are respectively connected to the control terminals of the switch tubes corresponding to the color temperature. When the control signal of a certain light source module is at high level, the switch tube connected to it is turned on , the output of the power converter drives the corresponding light source module to emit light through the switch tube. the

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