CN103944381A - Voltage output circuit based on PWM control - Google Patents
Voltage output circuit based on PWM control Download PDFInfo
- Publication number
- CN103944381A CN103944381A CN201410119320.9A CN201410119320A CN103944381A CN 103944381 A CN103944381 A CN 103944381A CN 201410119320 A CN201410119320 A CN 201410119320A CN 103944381 A CN103944381 A CN 103944381A
- Authority
- CN
- China
- Prior art keywords
- resistance
- operational amplifier
- triode
- pwm
- capacitor
- 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
Landscapes
- Amplifiers (AREA)
Abstract
The invention provides a voltage output circuit based on PWM control. The voltage output circuit based on PWM control is used for being connected between a PWM control signal and a load and is characterized in that the voltage output circuit comprises a filtering unit, a driving unit, an operational amplifier U1 and a feedback circuit, the filtering unit is used for converting the PWM signal into direct-current voltage and then outputting the direct-current voltage to the inverted input end of the operational amplifier U1, the positive-going input end of the operational amplifier U1 is grounded through a resistor R3, the output end of the operational amplifier U1 is connected to the driving unit through a resistor R4, and the feedback circuit is formed by a resistor R6 connected between the driving unit and the positive-going input end of the operational amplifier U1. The voltage output circuit based on PWM control well solves the problem that an existing voltage output circuit outputs low impedance in work and outputs high impedance in the idle state.
Description
Technical field
The present invention relates to lighting field, mainly by circuit, improve and optimizes the performance of illumination and stable etc., more specifically by, particularly relate to a kind of voltage follower circuit based on PWM control.
Background technology
Development along with electronic technology, occurred that multiple PWM(is the abbreviation of English Pulse Width Modulation, be called for short pulse-width modulation) technology, comprising: phase voltage is controlled PWM, pulsewidth PWM method, random PWM, SPWM method, line voltage control PWM etc., and the pulsewidth PWM method adopting in nickel-hydrogen battery smart charger, it be using each pulse duration all equal spike train as PWM waveform, can frequency modulation by changing the cycle of spike train, changing the width of pulse or duty ratio can pressure regulation, adopt suitable control method can make voltage and frequency coordination change.Can be by adjusting the cycle of PWM, the duty ratio of PWM reaches the object of controlling charging current.
At lighting field, also usually utilize PWM technology to control voltage input, thereby reach the effect of effective control lighting.But, there is such problem in current illumination control circuit, and, when illumination control is not worked, the output impedance of control circuit is not high, once controller lost efficacy, will affect the brightness of lighting; In addition, also there is the situation that burns out circuit because output current is too high in existing voltage follower circuit, thereby damage lighting or affect whole lighting mains.
Summary of the invention
The shortcoming of prior art in view of the above; the object of the present invention is to provide a kind of voltage follower circuit of controlling based on PWM; while being used for solving the work of prior art voltage follower circuit, export Low ESR; and the not high problem of output impedance while not working; protective circuit while simultaneously also providing output current too high, burns out the problem of circuit for solving existing voltage follower circuit because output current is too high.
For achieving the above object and other relevant objects, the invention provides following technical scheme:
A kind of voltage follower circuit of controlling based on PWM, be used for being connected between pwm control signal and load, it is characterized in that, comprise filter unit, driver element and operational amplifier U1, described filter unit is in order to convert pwm signal to the inverting input that is exported to described operational amplifier U1 after direct voltage, the positive input of described operational amplifier U1 is connected to described driver element by the output of resistance R 3 ground connection and this operational amplifier U1 by resistance R 4, this driver element is exported in order to the voltage signal obtaining is expanded to stream after described operational amplifier U1 amplifier after, and the feedback loop forming by the resistance R 6 being connected between described driver element and operational amplifier U1 positive input.The basic principle of the technical program is to utilize the input impedance of normal phase input end of amplifier higher than negative input impedance, and external triode output impedance is higher than amplifier output impedance, cuts off the loop with power supply simultaneously.
In above technical scheme, preferably, described filter unit comprises resistance R 1, resistance R 2, capacitor C 1 and capacitor C 2, and wherein, described resistance R 1 and resistance R 2 are connected in series in the reverse input end of described operational amplifier U1 successively; One end of described capacitor C 1 is connected between described resistance R 1 and resistance R 2, other end ground connection; One end of described capacitor C 2 is connected between described resistance R 2 and the reverse input end of described operational amplifier U1, other end ground connection.
Further, in above technical scheme, described driver element comprises triode Q1 and resistance R 5, the base stage of described triode Q1 is connected in the output of described operational amplifier U1 by described resistance R 4, the emitter of described triode Q1 is by ground connection after contact resistance R5, the collector electrode of described triode Q1 connects one end of described resistance R 6, and forms voltage output end by the emitter and collector of described triode Q1.
Further; on the basis of the above technical scheme, preferably, between the output of described operational amplifier U1 and described driver element, be also provided with an over-current protecting unit; this over-current protecting unit one end connects described resistance R 4, and the other end connects described driver element.Particularly; described over-current protecting unit at least comprises a triode Q2; the base stage of this triode Q2 is connected between the emitter and resistance R 5 of described triode Q1, and the collector electrode of triode Q2 is connected between resistance R 4 and the base stage of triode Q1, the grounded emitter of triode Q2.
By above technical scheme; the invention solves in prior art that voltage output control circuit is exported Low ESR when work and the not high problem of output impedance while not working; also by increasing output overcurrent protected location, further protected whole circuit because input current is too high, to burn out the problem of circuit simultaneously; thereby reduced the failure rate of light fixture, is also indirectly provided the useful life of lighting.
Accompanying drawing explanation
Fig. 1 a is shown as the circuit structure diagram of a kind of voltage follower circuit of controlling based on PWM of the present invention in embodiment mono-.
Fig. 1 b is shown as a kind of voltage follower circuit another circuit structure diagram in embodiment mono-of controlling based on PWM of invention.
Fig. 2 is shown as the circuit structure diagram of a kind of voltage follower circuit of controlling based on PWM in embodiment bis-.
Fig. 3 is shown as the circuit structure diagram of a kind of voltage follower circuit of controlling based on PWM in embodiment tri-.
Fig. 4 a is shown as the circuit structure diagram of a kind of voltage follower circuit of controlling based on PWM in embodiment tetra-.
Fig. 4 b is shown as a kind of voltage follower circuit of controlling based on PWM another circuit structure diagram in embodiment tetra-.
Drawing reference numeral explanation
10 filter units
20 driver elements
30 feedback loops
Embodiment
Below, by specific instantiation explanation embodiments of the present invention, those skilled in the art can understand other advantages of the present invention and effect easily by the disclosed content of this specification.The present invention can also be implemented or be applied by other different embodiment, and the every details in this specification also can be based on different viewpoints and application, carries out various modifications or change not deviating under spirit of the present invention.It should be noted that, in the situation that not conflicting, the feature in following examples and embodiment can combine mutually.
Refer to Fig. 1 to Fig. 4, it should be noted that, the diagram providing in following examples only illustrates basic conception of the present invention in a schematic way, satisfy and only show with assembly relevant in the present invention in graphic but not component count, shape and size drafting while implementing according to reality, during its actual enforcement, kenel, quantity and the ratio of each assembly can be a kind of random change, and its assembly layout kenel also may be more complicated.
The object of the present invention is to provide a kind of voltage follower circuit of controlling based on PWM, while being used for solving the work of prior art voltage follower circuit, export Low ESR, and the not high problem of output impedance while not working, protective circuit while simultaneously also providing output current too high, owing to solving in existing voltage follower circuit, because output current is too high, burn out the problem of circuit, compared with prior art, the present invention has optimized circuit, make Voltage-output precision high, driving force is strong, and there is output overcurrent protection, power-off output is the feature of high-impedance state, thereby improved the total quality of street lamp, operation effectively ensures safety.
Those skilled in the art mode with specific embodiment at length set forth to technical scheme of the present invention below, so that can implement the present invention better.
Embodiment mono-
See Fig. 1 a, show a kind of overall structure figure of the voltage follower circuit of controlling based on PWM, known according to figure, this circuit comprises filter unit, driver element and operational amplifier U1, described filter unit is in order to convert pwm signal to the inverting input that is exported to described operational amplifier U1 after direct voltage, the positive input of described operational amplifier U1 is connected to described driver element by the output of resistance R 3 ground connection and this operational amplifier U1 by resistance R 4, this driver element is exported in order to the voltage signal obtaining is expanded to stream after described operational amplifier U1 amplifier after, to drive load, in addition, this circuit also comprises the feedback loop that the resistance R 6 by being connected between described driver element and operational amplifier U1 positive input forms.
In the technical scheme of above enforcement one, first allow pwm signal pass through filter unit, this filter unit is in order to convert this pwm signal to d. c. voltage signal, and then this d. c. voltage signal is accessed to the reverse input end of described operational amplifier U1, the positive input of described operational amplifier U1 is ground connection, be that described operational amplifier U1 carries out operation amplifier to the d. c. voltage signal being converted to by this pwm signal, d. c. voltage signal after described operational amplifier U1 amplifies removes to drive described driver element again after resistance R 6, wherein this driver element is exported after the voltage signal of exporting after described d. c. voltage signal amplifier being expanded to stream, so that driving load.
Particularly, at filter unit described in the technical scheme of above embodiment mono-, comprise resistance R 1, resistance R 2, capacitor C 1 and capacitor C 2, wherein, described resistance R 1 and resistance R 2 are connected in series in the reverse input end of described operational amplifier U1 successively; One end of described capacitor C 1 is connected between described resistance R 1 and resistance R 2, other end ground connection; One end of described capacitor C 2 is connected between described resistance R 2 and the reverse input end of described operational amplifier U1, other end ground connection.
Above filter unit that is to say a secondary low-pass filter unit, by this secondary low-pass filter unit, the pwm signal of input is converted to d. c. voltage signal, its specific implementation principle is: by comprising the first order filtering of resistance R 1 and capacitor C 1, pwm signal is changed to pulsating direct current signal, through comprising the second level filtering of resistance R 2 and capacitor C 2, this pulsating direct current signal is converted to d. c. voltage signal again, is also about to pwm signal and is converted to d. c. voltage signal output.
Further, described driver element comprises triode Q1 and resistance R 5, the base stage of described triode Q1 is connected in the output of described operational amplifier U1 by described resistance R 4, the emitter of described triode Q1 is by ground connection after contact resistance R5, the collector electrode of described triode Q1 connects one end of described resistance R 6, and forms voltage output end by the emitter and collector of described triode Q1.
The effect of above driver element is exported in order to the voltage signal of exporting is expanded to stream after amplifier after, it realizes principle: the voltage signal of exporting after amplifier is controller triode Q1 after resistance R 4 dividing potential drops, makes up the problem of the current driving ability deficiency of the voltage signal of exporting after amplifier by the amplification of triode Q2.In addition, see Fig. 1 b, on the basis of above embodiment mono-technical scheme, increase again by a resistance R 7, one end of this resistance R 7 is connected between resistance R 4 and driver element (also at transistor base), other end ground connection, coordinates resistance R 4 in order to the voltage signal of exporting after amplifier is carried out to dividing potential drop by increasing resistance R 7, with this, meets the requirement of triode to base voltage in driver element.
Embodiment bis-
In order further to optimize or to enrich the present invention, will do some decision design to the present invention below, so that the present invention can be applied to the art better.See Fig. 2; show the structure chart of the present invention in embodiment bis-; particularly; technical scheme in the present embodiment two is the further optimization in the technical scheme in implementing; therefore except comprising all technical schemes in embodiment mono-; this enforcement two and enforcement one difference are: between the output of described operational amplifier U1 and described driver element, be also provided with an over-current protecting unit, this over-current protecting unit one end connects described resistance R 4, and the other end connects described driver element.
Particularly; described over-current protecting unit at least comprises a triode Q2; the base stage of this triode Q2 is connected between the emitter and resistance R 5 of described triode Q1, and the collector electrode of triode Q2 is connected between resistance R 4 and the base stage of triode Q1, the grounded emitter of triode Q2.
In the technical scheme of above embodiment bis-; described over-current protecting unit is used for when the output current of the triode Q1 of driver module surpasses set point; the voltage being connected in the resistance R 5 on described triode Q1 emitter will raise; thereby make triode Q1 saturation conduction; to drag down voltage in triode Q2 base stage; make triode Q2 cut-off, arrive the object that protection triode Q2 does not burn because electric current is excessive, also play the effect of overcurrent protection.
Implement three
Basis embodiment mono-or two, can also do further optimization to the present invention, see Fig. 3, show the present invention's particular circuit configurations schematic diagram in embodiment tri-, according to figure, the present embodiment three is except having and (be optimization on embodiment bis-bases in Fig. 3 technical scheme identical in embodiment mono-or embodiment bis-, because being, the optimization in enforcement one removes over-current protecting unit, those skilled in the art can be well understood to very much, so locate to omit, will not specifically illustrate), difference is that two capacitor C 3 and capacitor C 4 have also been added in this enforcement three, wherein, one end of described capacitor C 3 is connected between described operational amplifier U1 and resistance R 4, the other end is connected between described resistance R 6 and the positive input of operational amplifier U1, one end of described capacitor C 4 is connected between described resistance R 6 and described driver element, and the other end is connected between described resistance R 5 and described driver element.
Particularly, by the situation that having triode Q1 and triode Q2, one end of this capacitor C 4 is connected between resistance R 4 and triode Q1 base stage, the other end is connected between resistance R 6 and triode Q1 collector electrode; Utilize capacitor C 4 and capacitor C 3 to eliminate the self-oscillation of negative feedback amplifier circuit, increase the stability margin of circuit, thereby improve the stability of circuit.
Embodiment tetra-
Further, on the basis of above embodiment mono-, embodiment bis-and embodiment tri-, also can do further to optimize to the present invention, see Fig. 4 a, show the circuit structure diagram of the present invention in embodiment tetra-, according to figure, different from above all embodiment is, in this enforcement four, also added a capacitor C 5, this capacitor C 5 is connected in parallel on output one end of the voltage follower circuit that the present invention is based on PWM control, specific to implementing to be about to this capacitor C 5 in one, is parallel between the collector and emitter of triode Q1.
In addition, in Fig. 4 b, show the present invention at another circuit structure diagram of the present embodiment four, according to figure, it is to be mainly specially on the basis of triode Q1 at driver element, an external DC power supply VCC again on the collector electrode of triode Q1, also series resistor R8 and diode D1 successively between this DC power supply VCC and the collector electrode of triode Q1 simultaneously, the positive pole of this diode D1 connects this resistance R 8, negative pole connects the collector electrode of this triode Q1, by regulate the static point of triode at the extraneous DC power supply VCC of this triode Q1.The object that increases by a resistance R 8 between this power supply VCC and the collector electrode of triode Q1 is by resistance R 8, power supply VCC to be carried out the effect of dividing potential drop and current limliting, because if do not increase resistance R 8, so in actual debug process, output end voltage value will be limited by power supply VCC, thereby make circuit can not realize the object of voltage amplification.
In sum; the invention solves in prior art that voltage output control circuit is exported Low ESR when work and the not high problem of output impedance while not working; also by increasing output overcurrent protected location, further protected whole circuit because input current is too high, to burn out the problem of circuit simultaneously; thereby reduced the failure rate of light fixture, is also indirectly provided the useful life of lighting.So the present invention has effectively overcome various shortcoming of the prior art and tool high industrial utilization.
Above-described embodiment is illustrative principle of the present invention and effect thereof only, but not for limiting the present invention.Any person skilled in the art scholar all can, under spirit of the present invention and category, modify or change above-described embodiment.Therefore, such as in affiliated technical field, have and conventionally know that the knowledgeable, not departing from all equivalence modifications that complete under disclosed spirit and technological thought or changing, must be contained by claim of the present invention.
Claims (9)
1. a voltage follower circuit of controlling based on PWM, for being connected between pwm control signal and load, is characterized in that, comprising:
Operational amplifier U1;
Filter unit, pwm signal is converted to the inverting input that is exported to described operational amplifier U1 after direct voltage, the positive input of described operational amplifier U1 is by resistance R 3 ground connection;
Driver element, is connected to the output of described operational amplifier U1 by a resistance R 4, this driver element is exported in order to the voltage signal obtaining is expanded to stream after described operational amplifier U1 amplifier after; And
The feedback loop forming by the resistance R 6 being connected between described driver element and operational amplifier U1 positive input.
2. the voltage follower circuit of controlling based on PWM according to claim 1, it is characterized in that, described filter unit comprises resistance R 1, resistance R 2, capacitor C 1 and capacitor C 2, and wherein, described resistance R 1 and resistance R 2 are connected in series in the reverse input end of described operational amplifier U1 successively; One end of described capacitor C 1 is connected between described resistance R 1 and resistance R 2, other end ground connection; One end of described capacitor C 2 is connected between described resistance R 2 and the reverse input end of described operational amplifier U1, other end ground connection.
3. the voltage follower circuit of controlling based on PWM according to claim 1, it is characterized in that, described driver element comprises triode Q1 and resistance R 5, the base stage of described triode Q1 is connected in the output of described operational amplifier U1 by described resistance R 4, the emitter of described triode Q1 is by ground connection after contact resistance R5, the collector electrode of described triode Q1 connects one end of described resistance R 6, and forms voltage output end by the emitter and collector of described triode Q1.
4. the voltage follower circuit of controlling based on PWM according to claim 3, is characterized in that, the emitter and collector of the described triode Q1 capacitor C 5 that is also connected in parallel.
5. according to the arbitrary described voltage follower circuit of controlling based on PWM of claims 1 to 3; it is characterized in that; between the output of described operational amplifier U1 and described driver element, be also provided with an over-current protecting unit; this over-current protecting unit one end connects described resistance R 4, and the other end connects described driver element.
6. the voltage follower circuit of controlling based on PWM according to claim 5; it is characterized in that; described over-current protecting unit at least comprises a triode Q2; the base stage of this triode Q2 is connected between the emitter and resistance R 5 of described triode Q1; the collector electrode of triode Q2 is connected between resistance R 4 and the base stage of triode Q1, the grounded emitter of triode Q2.
7. the voltage follower circuit of controlling based on PWM according to claim 1, it is characterized in that, also comprise capacitor C 3 and capacitor C 4, wherein, one end of described capacitor C 3 is connected between described operational amplifier U1 and resistance R 4, and the other end is connected between described resistance R 6 and the positive input of operational amplifier U1; One end of described capacitor C 4 is connected between described resistance R 6 and described driver element, and the other end is connected between described resistance R 4 and described driver element.
8. the voltage follower circuit of controlling based on PWM according to claim 1, is characterized in that, the positive input of described operational amplifier U1 is by connecting the rear ground connection of a resistance R 3.
9. the voltage follower circuit of controlling based on PWM according to claim 1, is characterized in that, also comprise resistance R 7, one end of this resistance R 7 is connected between described resistance R 6 and described driver element, other end ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410119320.9A CN103944381A (en) | 2014-03-27 | 2014-03-27 | Voltage output circuit based on PWM control |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410119320.9A CN103944381A (en) | 2014-03-27 | 2014-03-27 | Voltage output circuit based on PWM control |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103944381A true CN103944381A (en) | 2014-07-23 |
Family
ID=51191912
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410119320.9A Pending CN103944381A (en) | 2014-03-27 | 2014-03-27 | Voltage output circuit based on PWM control |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103944381A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105163472A (en) * | 2015-10-30 | 2015-12-16 | 沈阳鼎越节能科技有限公司 | PWM ripple wave treatment and constant-current control circuit |
| CN105657887A (en) * | 2015-12-29 | 2016-06-08 | 浙江方大智控科技有限公司 | LED dimming circuit and LED driving circuit |
| CN108062054A (en) * | 2017-12-22 | 2018-05-22 | 深圳市英威腾电气股份有限公司 | A kind of analog signals output circuit |
| CN109274369A (en) * | 2018-08-29 | 2019-01-25 | 苏州瑞迈斯医疗科技有限公司 | A kind of scintillation pulse method for digitizing and device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1567721A (en) * | 2003-06-19 | 2005-01-19 | 台达电子工业股份有限公司 | PWM buffer circuit for regulating frequency and operating cycle of PWM signal |
| CN1838020A (en) * | 2005-03-23 | 2006-09-27 | 联发科技股份有限公司 | Switchable linear regulator |
| CN102025139A (en) * | 2010-11-11 | 2011-04-20 | 苏州合欣美电子科技有限公司 | Current expanding and limiting protection circuit of ecological house |
-
2014
- 2014-03-27 CN CN201410119320.9A patent/CN103944381A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1567721A (en) * | 2003-06-19 | 2005-01-19 | 台达电子工业股份有限公司 | PWM buffer circuit for regulating frequency and operating cycle of PWM signal |
| CN1838020A (en) * | 2005-03-23 | 2006-09-27 | 联发科技股份有限公司 | Switchable linear regulator |
| CN102025139A (en) * | 2010-11-11 | 2011-04-20 | 苏州合欣美电子科技有限公司 | Current expanding and limiting protection circuit of ecological house |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105163472A (en) * | 2015-10-30 | 2015-12-16 | 沈阳鼎越节能科技有限公司 | PWM ripple wave treatment and constant-current control circuit |
| CN105163472B (en) * | 2015-10-30 | 2017-09-05 | 沈阳鼎越节能科技有限公司 | The processing of PWM ripples and constant-current control circuit |
| CN105657887A (en) * | 2015-12-29 | 2016-06-08 | 浙江方大智控科技有限公司 | LED dimming circuit and LED driving circuit |
| CN108062054A (en) * | 2017-12-22 | 2018-05-22 | 深圳市英威腾电气股份有限公司 | A kind of analog signals output circuit |
| CN109274369A (en) * | 2018-08-29 | 2019-01-25 | 苏州瑞迈斯医疗科技有限公司 | A kind of scintillation pulse method for digitizing and device |
| CN109274369B (en) * | 2018-08-29 | 2022-05-10 | 苏州瑞迈斯医疗科技有限公司 | Method and device for digitizing scintillation pulse |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102856892B (en) | A kind of power supply | |
| CN203180783U (en) | Boosted circuit | |
| CN103944381A (en) | Voltage output circuit based on PWM control | |
| CN103152928A (en) | Load overvoltage protection circuit and control method thereof | |
| CN103298210B (en) | Overvoltage protection circuit and electronic device with same | |
| CN203368838U (en) | LED driver | |
| CN202696134U (en) | Power supply | |
| CN104577966A (en) | Overvoltage protection circuit | |
| CN204376382U (en) | For the protective circuit of LED high-voltage light bar | |
| CN205141638U (en) | Switching power supply output short circuit disconnection protection circuit | |
| CN201403045Y (en) | MOS tube driver circuit | |
| CN204168140U (en) | IGBT drive module, motor drive controller and power-driven system | |
| CN202773148U (en) | Backlight LED driving protective circuit under 3D state and television set | |
| CN202907251U (en) | Adjustable voltage stabilization power supply circuit and lamp | |
| CN203313057U (en) | Power supply circuit | |
| CN203151366U (en) | Double current loop circuit for controlling output voltage pulse width | |
| CN202602243U (en) | LED (Light-Emitting Diode) illumination power supply protection circuit | |
| CN205427683U (en) | Intelligent direct -current stabilized power supply | |
| CN206060723U (en) | Communicating circuit between AGV circuit boards | |
| CN204482097U (en) | A kind of high-power LED drive circuit | |
| CN204179633U (en) | A kind of short-circuit protection circuit of LED power | |
| CN105099236B (en) | A kind of VCC accessory power supplys power supply circuit | |
| CN204517360U (en) | Excess voltage protection | |
| CN104105245A (en) | LED driving protection circuit | |
| CN207118029U (en) | The circuit system of input high-low voltage defencive function is realized in a kind of non-isolated driving of common LED |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20140723 |