CN101742760A - Sine wave dimming control method and control device thereof - Google Patents
Sine wave dimming control method and control device thereof Download PDFInfo
- Publication number
- CN101742760A CN101742760A CN200810180118A CN200810180118A CN101742760A CN 101742760 A CN101742760 A CN 101742760A CN 200810180118 A CN200810180118 A CN 200810180118A CN 200810180118 A CN200810180118 A CN 200810180118A CN 101742760 A CN101742760 A CN 101742760A
- Authority
- CN
- China
- Prior art keywords
- unit
- sine wave
- modulation
- direct current
- pulsating direct
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The invention discloses a sine wave dimming control method and a control device thereof, which are used for controlling the brightness of a bulb. The sine wave dimming control method comprises the following steps of: firstly, providing an alternating voltage; secondly, rectifying the alternating voltage to obtain a first pulsating direct current; thirdly, modulating the first pulsating direct current to obtain a modulation wave; fourthly, filtering the modulation wave to obtain a second pulsating direct current; and finally, switching the second pulsating direct current by a switch unit so as to obtain a dimming alternating voltage for use by the bulb. The sine wave dimming control method switches the second pulsating direct current into the dimming alternating voltage in a mode of using the switch unit, and the dimming alternating voltage is a sine wave, so the bulb can work with the sine wave to achieve the technical effect of promoting power factors.
Description
Technical field
The present invention relates to a kind of light-dimming method and device, particularly relate to a kind of sine wave dimming control method and control device thereof of controlling the bulb brightness variation with alternating voltage.
Background technology
Generally be used for the light modulating device on the light fixture,, utilize lock stream superior characteristic of crystal own and condition, go to change the size of conduction angle with the method for phase control, to reach the purpose of control lamplight brightness mostly with lock stream crystalline phase control mode.This kind mode belongs to the semipermanent assembly because of lock stream crystal, and failure rate is low, so still used widely at present.
With reference to figure 1, be known phase modulation formula adjusting control circuit schematic diagram.Shown in Figure 1, control the conduction angle that is added on load 2 two ends output voltage V out by the dimmer circuit 1 that lock stream crystal (thyristor (SCR)/three-pole AC switch (TRIAC)) is formed.Figure 2 shows that known output voltage V out waveform, in Fig. 2, dimmer circuit 1 can be adjusted the conduction angle 21 of control output voltage Vout, and then reaches the effect of light modulation.
Yet, aforementioned phase modulation formula adjusting control circuit is to do the positive phase light modulation by SCR, this kind dimming mode belongs to simple and effectively control, but because use phase control mode can produce very big electric current surge (inrush current), and cause bulb to produce vibratory murmur, and can reduce bulb life.In addition, this dimming mode also can produce High-frequency Interference, and can power-supply system be exerted an adverse impact, moreover this dimming mode power factor (PowerFactor of also making load; PF) descend, and the alternating voltage of input can't be done effective use, and cause the waste of the energy.
Therefore dimming mode also has by isolated gate bipolar transistor (Insulated GateBipolar Transistor at present, IGBT) be used as reverse brightness adjustment control, surge and reduce influence to reduce electric current bulb life, but this kind control mode still belongs to phase control, the problem that has equally that serious interference, power-efficient can't promote, power factor is on the low side etc.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of sine wave dimming control method and control device thereof, to solve the problem that power factor that known dimming mode is caused is on the low side and power-efficient can't effectively promote.Therefore the objective of the invention is directly to provide sinusoidal wave, and control the luminosity of bulb, so that power factor can obviously promote by controlling sinusoidal wave voltage amplitude to bulb.
In order to solve the problems of the technologies described above, according to a kind of scheme of the present invention, provide a kind of sine wave dimming control method, in order to control the light source of a bulb, this method comprises: an alternating voltage is provided; Rectified AC voltage is to obtain one first pulsating direct current; Obtain a modulation ripple with mode modulation first pulsating direct current of a pulse width modulation (PWM); To the filtering of modulation ripple to obtain one second pulsating direct current; And switch the output of switching second pulsating direct current in the unit by one and use to bulb to obtain a light modulation alternating voltage; Wherein this switch unit is to make second pulsating direct current flow through respectively one first guiding path and one second guiding path and export and become the light modulation alternating voltage in an alternating manner, and is to allow second pulsating direct current bulb of flowing through with opposite direction between first guiding path and second guiding path.
In order to solve the problems of the technologies described above, according to a kind of scheme of the present invention, provide a kind of sine wave dimming control device, in order to control the light source of a bulb, comprising: a rectification unit, a modulation unit, a filter unit, switch a unit and a control unit.Wherein rectification unit is in order to an alternating voltage is carried out rectification and exports one first pulsating direct current; The modulation unit is to be coupled to rectification unit and first pulsating direct current is carried out modulation and exported a modulation ripple in the mode of pulse width modulation (PWM); Filter unit is to be coupled to the modulation unit and the modulation ripple is carried out filtering and to export one second pulsating direct current; Switch unit is to be coupled to filter unit, and switch unit provides one first guiding path and one second guiding path and comes second pulsating direct current switched to export a light modulation alternating voltage and use to bulb; Control unit is to couple switch unit, control unit is that this switch unit of control comes to flow through first guiding path and second guiding path respectively and export and become the light modulation alternating voltage for second pulsating direct current in an alternating manner, and is to allow second pulsating direct current this bulb of flowing through with opposite direction between first guiding path and second guiding path.
Therefore by above-mentioned execution mode, the present invention switches to the light modulation alternating voltage by the mode of switch unit with second pulsating direct current, and this light modulation alternating voltage is a sine wave, so bulb can be operated in sine wave, and reaches the technique effect that power factor promotes.
More than general introduction and ensuing detailed description and accompanying drawing all is to reach mode, means and the technique effect that predetermined purpose is taked in order to further specify the present invention.And relevant other purpose of the present invention and advantage will be set forth in follow-up explanation and accompanying drawing.
Description of drawings
Fig. 1 is known phase modulation formula adjusting control circuit schematic diagram;
Fig. 2 is the output voltage V out oscillogram among Fig. 1;
Fig. 3 is the flow chart of a sine wave dimming control method of preferred embodiment of the present invention;
Fig. 4 is for to come an alternating voltage is carried out the schematic diagram of brightness adjustment control by the method for Fig. 3;
Fig. 5 is for to come an alternating voltage is carried out another schematic diagram of brightness adjustment control by the method for Fig. 3;
Fig. 6 is the schematic diagram of one sine wave dimming control device of preferred embodiment of the present invention; And
Fig. 7 is the schematic diagram of another sine wave dimming control device of preferred embodiment of the present invention.
[main element mark description of drawings]
1 dimmer circuit
2 loads
21 conduction angles
40,50 rectification units
42,52 modulation unit
44,54 filter units
46,56 switch units
48,58 control units
421,521 pulse-width modulation drive circuits
S301~S311 flow chart step explanation
Embodiment
The invention provides a kind of high power factor (power factor that has; Pf) sine wave dimming control method and control device thereof, be used for the light-source brightness of a bulb is adjusted, and the focusing on of demand of the present invention directly provides sine wave to use for bulb, and just reaches dimming effect by changing sinusoidal wave voltage amplitude.
See also Fig. 3, it is the flow chart of a sine wave dimming control method of preferred embodiment of the present invention.The described sine wave dimming control method of present embodiment is to be used for the luminosity of a bulb is adjusted, and includes the following step:
At first obtain an alternating voltage (as step S301) from a power output end, this power output end can be a mains-supplied end;
Next this alternating voltage is carried out rectification to obtain the signal output (as step S303) of first pulsating direct current (first pulseDC);
Afterwards modulation is carried out in this first pulsating direct current and obtain modulation ripple output (as step S305), the modulation mode of this step is with high-frequency impulse width modulation (Pulse WidthModulation; PWM) come modulation is carried out in this first pulsating direct current, so that the voltage amplitude of first pulsating direct current height can be decided by the work period (duty cycle) of high-frequency impulse width;
And this modulation ripple obtains one second pulsating direct current output (secondpulse DC) (as step S307) through Filtering Processing again, owing to the modulation ripple is in high-frequency impulse width modulation mode modulation to be carried out in first pulsating direct current to obtain, therefore in the modulation ripple signal wave of carrying radio-frequency component secretly, so filtering mode is to come high-frequency signal in this modulation ripple of filtering by the low-pass filtering means;
Then the conversion process of this second pulsating direct current by AC/DC obtained light modulation alternating voltage output (as step S309), and this light modulation alternating voltage is to belong to sinusoidal wave (sinewave);
Last this light modulation alternating voltage is directly to supply with bulb to use (as step S311), so that bulb can come work shinny according to this light modulation alternating voltage, and the shinny brightness of bulb is that the voltage amplitude size of following the light modulation alternating voltage is done variation.
Wherein the conversion process of the described AC/DC of abovementioned steps S309 is to switch the unit by one to come the way of output of second pulsating direct current is switched, and when each half wave cycles of second pulsating direct current, come in an alternating manner to flow through one first guiding path and one second guiding path respectively and export and become this light modulation alternating voltage, and be to allow second pulsating direct current bulb of flowing through between first guiding path and second guiding path with opposite direction for second pulsating direct current.
The waveform of each step gained when carrying out in order more to clearly demonstrate Fig. 3, can consult Fig. 4 and Fig. 5 respectively, wherein Fig. 4 is the waveform that each step execution gained of Fig. 3 is described in the mode of full-wave rectification, and Fig. 5 is the waveform that each step execution gained of Fig. 3 is described in the mode of halfwave rectifier.
At first see also Fig. 4 and cooperate Fig. 3 in the lump, alternating voltage A obtains one first pulsating direct current B through way of full-wave rectification in Fig. 4, and this first pulsating direct current B belongs to an all-wave pulsating direct current, this first pulsating direct current afterwards is to obtain a modulation ripple C via the processing of high-frequency impulse width modulation, this modulation ripple C is again via obtaining one second pulsating direct current D after the low-pass filtering treatment, again this second pulsating direct current D is obtained a light modulation alternating voltage E with the conversion process of AC/DC afterwards, and this light modulation alternating voltage is to belong to sinusoidal wave and directly use for bulb.
Then please consult Fig. 5 again and cooperate Fig. 3 in the lump, alternating voltage A ' just obtains through the halfwave rectifier mode among Fig. 5, the one first pulsating direct current B ' that negative half period separates, this first pulsating direct current B ' handles and just obtains via the high-frequency impulse width modulation afterwards, the modulation ripple C ' that negative half period separates, this modulation ripple C ' just obtains via after the low-pass filtering treatment again, the one second pulsating direct current D ' that negative half period separates, again this second pulsating direct current D ' is obtained a light modulation alternating voltage E ' with the conversion process of AC/DC afterwards, and this light modulation alternating voltage is to belong to sinusoidal wave and directly use for bulb.
Next see also Fig. 6, it is the schematic diagram for one sine wave dimming control device of preferred embodiment of the present invention.The sine wave dimming control device includes a rectification unit 40, a modulation unit 42, a filter unit 44, a switching unit 46 and a control unit 48.Wherein rectification unit 40 is to receive alternating voltage input, and this ac voltage rectifier is become one first pulsating direct current output, and rectification unit 40 is to implement with full-wave rectifying circuit (as bridge rectifier) in the present embodiment.
Moreover in order to allow the voltage amplitude height of supplying with the sine wave that bulb uses can precisely meet the input voltage Vset that sets, control unit 48 is to adopt the mechanism of FEEDBACK CONTROL to reach.Control unit 48 is to obtain a feedback voltage with feedback system from the bulb end, and this feedback voltage and input voltage Vset are compared, when feedback voltage during greater than input voltage Vset, and the work period of then reducing the PWM1 control signal; Opposite to feedback voltage during less than input voltage Vset, the work period of then improving the PWM1 control signal.And how obtaining this feedback voltage as for control unit 48, this technology belongs to the technology that these those skilled in the art should know, for example can be by at bulb side and connect the voltage that a transformer T1 obtains bulb side.
In addition, control unit 48 also further provides control to switch unit 46, for example control unit 48 is the ON time by control its switch SW1~SW4, and allows second pulsating direct current alternately flow through bulb by first guiding path and second guiding path.Further, control unit is obtained alternating voltage from the Vin input, and when positive half cycle control unit 48 control its switch SW1 and the SW4 conducting during cycle at alternating voltage, and diverter switch SW2 and SW3 end; Otherwise when negative half period control unit 48 control its switch SW2 and the SW3 conducting during cycle at alternating voltage, and diverter switch SW1 and SW4 end.
Next please consult Fig. 7 again, it is the schematic diagram of another sine wave dimming control device of one of preferred embodiment of the present invention.The sine wave dimming control device includes a rectification unit 50, a modulation unit 52, a filter unit 54, a switching unit 56 and a control unit 58.Wherein rectification unit 50 is to receive alternating voltage input, and one first pulsating direct current that this ac voltage rectifier becomes positive and negative half cycle to separate is exported.Rectification unit 50 is to implement with half-wave rectifying circuit in the present embodiment, and this half-wave rectifying circuit includes the positive half cycle half-wave rectifying circuit of diode D2 formation and the negative half period half-wave rectifying circuit that diode D3 constitutes.
Moreover in order to allow the voltage amplitude height of supplying with the sine wave that bulb uses can precisely meet the input voltage that sets, control unit 58 is to adopt the mechanism of FEEDBACK CONTROL to reach, and this feedback controling mode is identical with the mode of earlier figures 6, does not repeat them here.In addition, control unit 58 also further provides control to switch unit 56, when the positive half cycle of alternating voltage during the cycle control unit 58 are control its switch SW5 conductings, and diverter switch SW6 ends; And when the negative half period of alternating voltage during the cycle control unit 58 are control its switch SW6 conductings, and diverter switch SW5 ends.
The aforementioned power switch of mentioning can for the isolated gate bipolar transistor (Insulated GateBipolar Transistor, IGBT) or metal-oxide half field effect transistor (MOSFET).Diverter switch can be thyristor (Silicon Controlled Rectifier; SCR).Control unit can pass through microprocessor (micro-processor), microcontroller (MCU) or single-chip (SOC), at this to the explanation of power switch, diverter switch and control unit as an example usefulness only, be not in order to limit the scope of the invention, everyly can reach these feature operations by other electronic building brick, all be to belong within the claim scope of the present invention.
By above stated specification, sine wave dimming control method of the present invention is afterwards directly to provide sinusoidal wave to use to bulb through the described step process of Fig. 3, and controls this sinusoidal wave voltage amplitude size by the modulation unit.Therefore can eliminate the electric current of surging (inrush current) fully by mode of the present invention, and can thoroughly eliminate bulb and on business know and adopt the mechanical nose that phase control dimming produces and the High-frequency Interference of power line bulb.So dimming mode of the present invention can allow power factor remain on more than 98%, and can reach the highest power-efficient.
But above-mentioned disclosed accompanying drawing, explanation only are embodiments of the invention; non-so promptly limit to scope of patent protection of the present invention; so the equivalent structure that all utilizations specification of the present invention and accompanying drawing content are done changes, and all in like manner is contained in protection scope of the present invention explanation hereby.
Claims (20)
1. a sine wave dimming control method is characterized in that, in order to control the light source of a bulb, this method comprises:
One alternating voltage is provided;
This alternating voltage is carried out rectification to obtain one first pulsating direct current;
Mode with a pulse width modulation is carried out modulation and is obtained a modulation ripple this first pulsating direct current;
This modulation ripple is carried out filtering and obtains one second pulsating direct current; And
Provide one to switch the unit and come this second pulsating direct current switched and obtain a light modulation alternating voltage to use to this bulb;
Wherein this switch unit is to come in an alternating manner to flow through one first guiding path and one second guiding path respectively and export and become this light modulation alternating voltage for this second pulsating direct current, and is to allow this second pulsating direct current this bulb of flowing through with opposite direction between this first guiding path and this second guiding path.
2. sine wave dimming control method as claimed in claim 1 is characterized in that, wherein this alternating voltage being carried out rectification is to be undertaken by a full-wave rectifying circuit.
3. sine wave dimming control method as claimed in claim 1 is characterized in that, wherein this alternating voltage being carried out rectification is to be undertaken by a positive half cycle half-wave rectifying circuit and a negative half period half-wave rectifying circuit.
4. sine wave dimming control method as claimed in claim 1, it is characterized in that, wherein the modulation that this first pulsating direct current is carried out is the conducting of controlling at least one power switch by a pulse-width modulation drive circuit, and this power switch obtains this modulation ripple and this first pulsating current is flowed through.
5. sine wave dimming control method as claimed in claim 4 is characterized in that, wherein the adjustment of this employed work period of pulse-width modulation drive circuit is the control according to a control unit.
6. sine wave dimming control method as claimed in claim 5 is characterized in that, wherein this control unit is adjusted this work period according to a feedback voltage of an input voltage and this bulb.
7. sine wave dimming control method as claimed in claim 6 is characterized in that, wherein when this feedback voltage during greater than this input voltage, this control unit is turned down this work period.
8. sine wave dimming control method as claimed in claim 6 is characterized in that, wherein when this feedback voltage during less than this input voltage, this control unit is heightened this work period.
9. sine wave dimming control method as claimed in claim 6 is characterized in that, wherein the conducting of this first guiding path and this second guiding path is to be controlled by this control unit.
10. sine wave dimming control method as claimed in claim 1 is characterized in that, wherein this modulation ripple being carried out filtering is by a low-pass filter circuit.
11. a sine wave dimming control device is characterized in that, in order to control the light source of a bulb, comprising:
One rectification unit is in order to carry out rectification to export one first pulsating direct current to an alternating voltage;
One modulation unit is coupled to this rectification unit, and this first pulsating direct current is carried out modulation to export a modulation ripple in the mode of pulse width modulation;
One filter unit is coupled to this modulation unit, and this modulation ripple is carried out filtering to export one second pulsating direct current;
One switches the unit, is coupled to this filter unit, and this switch unit provides one first guiding path and one second guiding path comes this second pulsating direct current is switched to export a light modulation alternating voltage to this bulb use; And
One control unit, couple this switch unit, this control unit is controlled this switch unit and is come in an alternating manner to flow through this first guiding path and this second guiding path respectively and export and become this light modulation alternating voltage for this second pulsating direct current, and is to allow this second pulsating direct current this bulb of flowing through with opposite direction between this first guiding path and this second guiding path.
12. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this rectification unit is a full-wave rectifying circuit.
13. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this rectification unit includes a positive half cycle half-wave rectifying circuit and a negative half period half-wave rectifying circuit.
14. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this modulation unit includes:
One pulse-width modulation drive circuit and at least one power switch, wherein this pulse-width modulation drive circuit is the conducting of this power switch of control, obtains this modulation ripple so that this first pulsating direct current of this power switch of flowing through is dammed;
Wherein this control unit is coupled to this modulation unit, and the adjustment of the work period of the employed pwm control signal of this pulse-width modulation drive circuit is the control that is subjected to this control unit.
15. sine wave dimming control device as claimed in claim 14 is characterized in that, wherein this power switch is isolated gate bipolar transistor or metal-oxide half field effect transistor.
16. sine wave dimming control device as claimed in claim 14, it is characterized in that, wherein this control unit is to adjust this work period according to a feedback voltage of an input voltage and this bulb, and when this feedback voltage during greater than this input voltage, this control unit is turned down the work period of this pwm control signal, and when this feedback voltage during less than this input voltage, this control unit is heightened the work period of this pwm control signal.
17. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this control unit is controlled this first guiding path in the positive half cycle conducting of this alternating voltage and control the negative half period conducting of this second guiding path at this alternating voltage.
18. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this switch unit is to have a plurality of diverter switches, and this control unit forms this first guiding path and this second guiding path by the conducting of controlling those diverter switches.
19. sine wave dimming control device as claimed in claim 18 is characterized in that, wherein this diverter switch is for being thyristor.
20. sine wave dimming control device as claimed in claim 11 is characterized in that, wherein this filter unit is a low-pass filter circuit.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN200810180118A CN101742760A (en) | 2008-11-27 | 2008-11-27 | Sine wave dimming control method and control device thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN200810180118A CN101742760A (en) | 2008-11-27 | 2008-11-27 | Sine wave dimming control method and control device thereof |
Publications (1)
Publication Number | Publication Date |
---|---|
CN101742760A true CN101742760A (en) | 2010-06-16 |
Family
ID=42465428
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN200810180118A Pending CN101742760A (en) | 2008-11-27 | 2008-11-27 | Sine wave dimming control method and control device thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN101742760A (en) |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1070303A (en) * | 1991-09-06 | 1993-03-24 | 浙江舞台电子技术研究所 | Pulse width modulation type AC light regulating circuit |
US5969484A (en) * | 1998-05-14 | 1999-10-19 | Optimum Power Conversion, Inc. | Electronic ballast |
-
2008
- 2008-11-27 CN CN200810180118A patent/CN101742760A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1070303A (en) * | 1991-09-06 | 1993-03-24 | 浙江舞台电子技术研究所 | Pulse width modulation type AC light regulating circuit |
US5969484A (en) * | 1998-05-14 | 1999-10-19 | Optimum Power Conversion, Inc. | Electronic ballast |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN102083254B (en) | WLED driving circuit and driving method suitable for three-terminal controlled silicon dimmer | |
CN101835314B (en) | LED drive circuit with dimming function and lamp | |
US20150195878A1 (en) | Led driver | |
CN107046750B (en) | Using PWM mode to the LED drive device of lamps and lanterns stepless dimming | |
CN102065600A (en) | LED dimming driving system | |
Baek et al. | Single-stage buck-derived LED driver with improved efficiency and power factor using current path control switches | |
US9748844B2 (en) | Systems and methods for controlling and improving power converters | |
JP2023141472A (en) | AC-DC power supply | |
CN205378285U (en) | LED lamp lighting system based on PWM adjusts luminance | |
CN204191007U (en) | Led drive device | |
WO2014139399A1 (en) | An electrical load driving apparatus | |
CN203181303U (en) | Light modulator used for voltage drop dimming light fixture | |
CN205961512U (en) | LED light modulator and LED drive arrangement | |
WO2015107498A1 (en) | Power control by phase cutting | |
Ma et al. | Control scheme for TRIAC dimming high PF single-stage LED driver with adaptive bleeder circuit and non-linear current reference | |
CN210093612U (en) | LED double-color dimming built-in power supply | |
CN107404784B (en) | Dimming module, dimming method and lighting device | |
CN106102245B (en) | LED dimmer, LED light-dimming method and LED drive device | |
KR101367383B1 (en) | Ac led dimmer | |
CN101742760A (en) | Sine wave dimming control method and control device thereof | |
CN205196033U (en) | Wireless LED power of adjusting luminance | |
CN203167350U (en) | LED drive circuit with capabilities of light modulation and color temperature adjustment | |
Chowdhury et al. | An electrically isolated low power LED driver offering power factor correction with ameliorated mains current THD | |
Sekhar et al. | Input regulated soft switched ripple free current LED driver | |
CN107072020A (en) | A kind of single-stage HID digital ballast circuits based on piezoelectric transformer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20100616 |