TWI468075B - A dimming device - Google Patents

Description

Light dimming device

The invention relates to a dimming technology for a lighting device, and aims to provide a lighting device capable of dimming using a light emitting diode (LED) or a cold cathode lamp (CCFL) as a light source at an alternating current end without causing flicker. The dimming method and the dimming device associated therewith.

According to the policy of energy saving and carbon reduction, and the policy of governments to ban incandescent bulbs in the future, the advantages of high efficiency, energy saving and dimming of light emitting diodes (LEDs) have been in the lighting market. It has gradually formed a trend, and its application in street lamps, car lights, outdoor lighting, and situational lighting has become the focus of attention worldwide.

In the traditional lighting technology field, dimmers are often used to adjust the brightness of lighting equipment; similar dimmers (such as Tri-electrode AC switch, TRIAC) provide voltage according to their conduction conditions to fine-tune the resistance. Lighting device lighting elements (such as halogen lamps, tungsten lamps, etc.), so the dimmer inside the home can be set separately from the lighting device (for example, the dimmer is placed in the appropriate position on the wall), to facilitate user adjustment The purpose of lighting brightness.

Furthermore, a lighting device using a light-emitting diode (LED) or a cold cathode lamp (CCFL) as a light source converts a commercial alternating current into a low-voltage direct current for use by an LED or a CCFL thereof via a DC-AC boost/ Frequency conversion, that is, driven by the line to emit light. Since the circuit characteristics of the light-emitting diode (LED) exhibit a capacitive characteristic, when the brightness of the light source of the LED light bulb is directly controlled by the dimmer, when the dimmer (TRIAC) operates, the waveform cannot be synchronized and cannot be synchronized to cause flicker. The phenomenon.

Therefore, there is a light-emitting diode lighting device that first adjusts the input mains AC power supply to a dimming AC power source through a dimming control unit composed of a dimmer and a transformer unit, and then passes through a multiple of a driving device. The pressing unit doubles the dimming AC power and converts it into a DC power source, so that the driving DC power generated by the voltage doubler is within the operating voltage range of the dimming driving unit, thereby driving the LED and avoiding the LED The body flickers during dimming. However, such a design not only complicates the overall dimming circuit architecture, but also has low interchangeability of the lighting device itself, and relatively increases the manufacturing cost of the lighting device.

In view of the above, the present invention provides a dimming method capable of dimming an illumination device using a light-emitting diode (LED) or a cold cathode lamp (CCFL) as a light source at an alternating current end without causing flicker. The dimming device is its main purpose.

In order to achieve the above object, a dimming method of the present invention is mainly provided with a phase comparison unit connected between the rectifying unit and the oscillating unit on the primary side of the transforming unit of the illuminating device, and the phase comparing unit is used to obtain the output of the rectifying unit. The frequency-doubled frequency signal of the pulsed DC signal is used as a reference phase, and the AC power signal θ phase angle synchronization signal is transmitted to the enable control terminal of the oscillating unit, so that the oscillating circuit frequency of the oscillating unit and the frequency θ phase of the output of the rectifying unit The angle is synchronized, so as to avoid the phase of the AC power source being caused by the adjustment of the tuner (TRAIC) to cause the illumination source to flicker.

A dimming device of the present invention includes: a rectifying unit, an oscillating unit, a transforming unit, and a phase comparing unit; wherein the rectifying unit is configured to obtain a mains AC sine wave periodic signal and convert it into a a pulsed DC signal of a full-spindle waveform of a positive period; the oscillating unit is configured to obtain a pulsed DC signal of the rectifying unit as a level signal to determine an output power-on period signal; the transformer unit is for each voltage The pulse signal receives the continuous voltage pulse signal, and operates the output voltage to the photoelectric component of the illumination device according to the input voltage of each voltage pulse signal.

The phase comparison unit is configured to obtain a frequency multiplied frequency signal of the pulsed DC signal outputted by the rectifying unit as a reference phase, and obtain an AC power signal θ phase angle synchronization signal to be sent to an enable control terminal of the oscillating unit to make the oscillating unit The oscillating circuit frequency is synchronized with the phase angle of the multiplied signal θ output by the rectifying unit.俾 Achieve the purpose of avoiding the phase of the AC power source due to the adjustment of the tuner (TRAIC) to cause the lighting source to flicker.

According to the above main structural features, the phase comparison unit further includes: a voltage dividing circuit, a filter circuit, a clamp circuit, and a switching element; wherein the voltage dividing circuit is configured to obtain a pulse of the rectifying unit The frequency multiplied frequency signal of the direct current signal is used as a reference phase; the filter circuit is used for reducing noise of the frequency doubled frequency signal; the clamp circuit is configured to limit the voltage of the frequency doubled frequency signal to be between 5 and 10V The switching element is set when the frequency multiplied frequency signal is Low, the switching element is not turned on (open circuit), and is set when the frequency multiplied frequency signal is High, the switching element is turned on (closed), Then, the oscillating unit is synchronously oscillated to achieve the purpose of synchronizing the oscillating circuit frequency of the oscillating unit with the phase angle of the multiplied signal θ output by the entire stream unit.

The above switching element may be one of a transistor, a MOSFET, and an OP comparator.

According to the above main structural features, a power factor control unit (PFC) is electrically connected between the rectifying unit and the oscillating unit.

The present invention can produce the following effects:

1. It can effectively solve the problem that the lighting device using the light-emitting diode (LED) or the cold cathode lamp (CCFL) as the light source will cause flicker when dimming through the dimmer (TRIAC).

2. The dimming device (TRIAC) can be used for dimming at the AC end, which greatly simplifies the dimming line of the lighting device and reduces the manufacturing cost of the lighting device.

3. Dimming can be performed on the AC side with a dimmer (TRIAC), which greatly increases the interchangeability of lighting equipment.

The features of the present invention can be clearly understood by referring to the drawings and the detailed description of the embodiments.

The present invention mainly provides a dimming method capable of dimming an illumination device using a light emitting diode (LED) or a cold cathode lamp (CCFL) as a light source at an alternating current end without causing flicker, and a dimming device associated therewith; As shown in the first figure, a dimming method of the present invention is mainly provided with a phase comparison unit 40 connected between the rectifying unit 10 and the oscillating unit 20 on the primary side of the transforming unit 30 of the illuminating device, and the phase comparing unit is utilized. 40: Obtaining the frequency multiplied frequency signal of the pulsed DC signal outputted by the rectifying unit 10 as a reference phase, and obtaining the AC power signal θ phase angle synchronization signal is transmitted to the enabling control end of the oscillating unit 20, so that the oscillating circuit frequency of the oscillating unit 20 Synchronizing with the phase angle of the multiplied signal θ output by the rectifying unit 10, the phase of the AC power source is avoided by the dimmer (TRAIC). The adjustment changes cause the lighting source to flicker.

With reference to the second figure, a dimming device of the present invention includes: a rectifying unit 10, an oscillating unit 20, a transforming unit 30, and a phase comparing unit 40; wherein: the rectifying unit 10 It is used to obtain the AC sine wave periodic signal of the mains and convert it into a full-string pulsed DC signal with a positive period. The oscillating unit 20 is configured to obtain a pulsed direct current signal of the rectifying unit 10 as a level signal to determine an output power on period signal; the transforming unit 30 is configured to receive a continuous voltage pulse signal corresponding to each voltage pulse signal. And outputting the voltage to the optoelectronic component 50 of the illumination device according to the input voltage of each voltage pulse signal. The optoelectronic component 50 can be a light emitting diode (LED) or a cold cathode lamp (CCFL).

The phase comparison unit 40 is configured to obtain a frequency multiplied frequency signal of the pulsed DC signal outputted by the rectifying unit 10 as a reference phase, and obtain an AC power signal θ phase angle synchronization signal to be transmitted to the enabling control end of the oscillating unit 20, The oscillation circuit frequency of the oscillating unit 20 is synchronized with the phase angle of the multiplied signal θ output by the rectifying unit.俾 Achieve the purpose of avoiding the phase of the AC power source due to the adjustment of the tuner (TRAIC) to cause the lighting source to flicker. Of course, the overall dimming device can further electrically connect a power factor control unit (PFC) 60 between the rectifying unit 10 and the oscillating unit 20 to improve the power usage rate.

In the implementation of the present invention, the phase comparison unit 40 further includes: a voltage dividing circuit 41, a filter circuit 42, a clamp circuit 43, and a switching element 44; wherein: the voltage dividing circuit 41 is provided Obtaining a frequency multiplied frequency signal of the pulsed DC signal of the rectifying unit 10 as a reference phase; the filtering circuit 42 is configured to reduce the multiple The noise of the frequency frequency signal; the clamp circuit 43 is used to limit the voltage of the frequency doubling frequency signal to be between 5 and 10V.

As for the switching element 44, it may be a transistor, a metal oxide semiconductor field effect transistor (MOSFET), an operational amplifier (OP) comparator, and in the embodiment shown in the figure, a transistor, mainly for setting When the frequency multiplied frequency signal is low, the transistor is not turned on (is an open circuit), and is set when the frequency doubling frequency signal is high (High), the transistor is turned on (closed), and at this time The oscillating unit 20 synchronously oscillates to achieve the purpose of synchronizing the oscillating circuit frequency of the oscillating unit 20 with the phase angle of the multiplied signal θ output by the entire stream unit 10.

Compared with the conventional technology, the dimming method and the related dimming device thereof can effectively solve the problem that the lighting device using the light emitting diode (LED) or the cold cathode lamp (CCFL) as the light source passes through the dimmer (TRIAC) The problem of flickering occurs when dimming; in particular, the dimming method disclosed in the present invention and the dimming device associated therewith can be dimmed at the AC end by using a dimmer (TRIAC), which greatly simplifies the tuning of the lighting device. The optical line reduces the manufacturing cost of the lighting device, and thus greatly increases the interchangeability of the lighting device.

As described above, the present invention provides a preferred dimming method and a dimming device associated therewith using a light-emitting diode (LED) or a cold cathode lamp (CCFL) as a light source, and presenting a patent for invention according to law. The application and the technical features of the present invention are disclosed above, but those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should be construed as being limited by the scope of the appended claims

10‧‧‧Rectifier unit

20‧‧‧Oscillation unit

30‧‧‧Transformer unit

40‧‧‧ phase comparison unit

41‧‧‧voltage circuit

42‧‧‧Filter circuit

43‧‧‧Clamp circuit

44‧‧‧Switching elements

50‧‧‧Optoelectronic components

60‧‧‧Power Factor Control Unit (PFC)

The first figure is a basic composition diagram of the dimming device of the present invention.

The second figure is a circuit diagram of a phase comparison unit according to a preferred embodiment of the present invention.

10. . . Rectifier unit

20. . . Oscillation unit

30. . . Transformer unit

40. . . Phase comparison unit

50. . . Optoelectronic component

60. . . Power Factor Control Unit (PFC)

Claims (3)

A dimming device includes: a rectifying unit configured to obtain a mains alternating current sine wave periodic signal and converted into a pulsed direct current signal having a full-period waveform; and an oscillating unit for obtaining the rectifying The pulsed DC signal of the unit is used as a level signal to determine an output power on period signal; a transformer unit is configured to receive a continuous voltage pulse signal corresponding to each voltage pulse signal, and an input voltage according to each voltage pulse signal Actuating the output voltage to the optoelectronic component of the illumination device; a phase comparison unit for obtaining the multiplied frequency signal of the pulsed DC signal outputted by the rectifying unit as the reference phase, and obtaining the AC power signal θ phase angle synchronization signal is transmitted to the oscillating unit The control terminal is configured to synchronize the oscillation circuit frequency of the oscillating unit with the phase angle of the multiplication signal θ output by the rectifying unit, and the phase comparison unit has a voltage dividing circuit, a filtering circuit, a clamping circuit and a switching element. The voltage dividing circuit is configured to obtain a frequency multiplied frequency signal of the pulsed direct current signal of the rectifying unit as a reference phase, and the filtering The circuit is configured to reduce the noise of the frequency doubling frequency signal, the clamping circuit is configured to limit the voltage of the frequency doubling frequency signal to be between 5 and 10V, and the switching component is set to be low at the frequency doubling frequency signal ( Low), the switching element is not turned on, and is set when the frequency multiplied frequency signal is high (High), the switching element is turned on, and at this time, the oscillating unit is synchronously oscillated. The dimming device of claim 1, wherein the switching element is one of a transistor, a metal oxide semiconductor field effect transistor (MOSFET), and an operational amplification (OP) comparator. The dimming device of claim 1, wherein the rectifying A power factor control unit (PFC) is electrically connected between the unit and the oscillating unit.