CN203691696U - Bridgeless LED drive circuit - Google Patents
Bridgeless LED drive circuit Download PDFInfo
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- CN203691696U CN203691696U CN201320864033.1U CN201320864033U CN203691696U CN 203691696 U CN203691696 U CN 203691696U CN 201320864033 U CN201320864033 U CN 201320864033U CN 203691696 U CN203691696 U CN 203691696U
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- control circuit
- led drive
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Abstract
The utility model discloses a bridgeless LED (Light Emitting Diode) drive circuit, comprising a switch tube (Q1), a switch tube (Q2), an input power supply (V1), a diode (D1), a diode (D2), and an inductor (L1); wherein a drain electrode of the switch tube (Q1) is connected with a positive electrode of the diode (D1), and the drain electrode of the switch tube (Q1) is connected with a first end of the input power supply (V1) through the inductor (L1); a drain electrode of the switch tube (Q2) is connected with a positive electrode of the diode (D2), and the drain electrode of the switch tube (Q2) is connected with a second end of the input power supply (V1) through the inductor (L1); the bridgeless LED drive circuit also comprises a peak value control circuit configured to sample peak value currents of the switch tube (Q1) and the switch tube (Q2), and to control conduction or closing of the switch tube (Q1) and the switch tube (Q2) through grid electrodes of the switch tube (Q1) and the switch tube (Q2).
Description
Technical field
The utility model relates to a kind of LED drive circuit, relates in particular to a kind of without bridge LED drive circuit.
Background technology
In illumination application, LED, because it has the features such as energy-saving and environmental protection, the life-span is long, volume is little, can be widely used in various light fixtures.The most of low-voltage DC that adopts of existing LED light fixture, as 12V, 24V.In order to use civil power 220V alternating current, between them, just need to add transformer and drive circuit, in order to driving LED.Transformer, be divided into linear transformer and electronic transformer, drive circuit is made up of rectifier bridge and DC transfer circuit, rectifier bridge can bring certain conducting kwh loss, especially electronic transformer is used in LED more and more, due to electronic transformer output be high-frequency ac square wave, rectifier bridge needs high frequency switch operating, simultaneously, in order to maintain the electronic transformer input of normally vibrating, the electric current that flows to rectifier bridge must ensure a minimum amplitude.In this case, the conduction loss of rectifier bridge is just more obvious, and in the concrete instance of 3.5W power LED lamp, the application of rectifier bridge can bring 8% decrease in efficiency.
As shown in Figure 1, for using the LED circuit system block diagram of rectifier bridge in prior art, LED circuit receives external ac power source, generally, this AC power is 220V or 110V civil power, then carries out transformation by electronic transformer or linear transformer, and 220V, 110V AC power are become to low pressure, as 12V, 24V etc.In the time carrying out transformation by linear transformer, the voltage of linear transformer output is civil power same frequency, synchronous sine wave, and in the time carrying out transformation by electronic transformer, the voltage of electronic transformer output is high-frequency ac square wave.In Fig. 1, the rectifier circuit of diode D1, diode D2, diode D3, diode D4 composition, is converted into direct current by input power V1 from alternating current, and exports to LED light source by the DC transfer circuit connecting.
As shown in Figure 2, for in prior art, use single inductance without bridge circuit schematic diagram, in figure, input power V1 first end connects the positive pole of diode D1 by an inductance L 1, adding inductance is mainly the effect of playing storage power and releasing energy in switching tube Q1, Q2 work, and inductance L 1 is boost inductance.
As shown in Figure 3, in prior art, use coupling inductance without bridge circuit schematic diagram.In figure, one end of input power V1 connects the positive pole of this diode D1 by an inductance L 1, and the second end of this input power V1 connects the positive pole of this diode D2 by an inductance L 2, and this inductance L 1 and this inductance L 2 are coupled, composition common mode inductance.
Prior art all need feed back input voltage and input current without bridge LED drive circuit, feedback circuit is very loaded down with trivial details like this, complexity.
Utility model content
In order to overcome above-mentioned technological deficiency, the purpose of this utility model is to provide a kind of LED drive circuit of non-rectifying bridge structure can reduce the heating of circuit and raise the efficiency.
The utility model discloses a kind of LED drive circuit, comprise, switching tube (Q1), switching tube (Q2), input power (V1), diode (D1), diode (D2), inductance (L1), described switching tube (Q1) drain electrode is connected with described diode (D1) is anodal, and described switching tube (Q1) drain electrode is connected with the first end of described input power (V1) by inductance (L1); Described switching tube (Q2) drain electrode is connected with described diode (D2) is anodal, and described switching tube (Q2) drain electrode is connected with the second end of described input power (V1) by inductance (L1); Also comprise peak value control circuit, described peak value control circuit be configured to the to sample peak current of described switching tube (Q1) and described switching tube (Q2), and by switching tube (Q1) and (Q2) conducting of described switching tube or closure described in the grid control of described switching tube (Q1) and described switching tube (Q2).
Preferably, comprise sample circuit, control circuit at the control circuit of peak value described in the utility model, described sample circuit be configured to the to sample peak current of described switching tube (Q1) and described switching tube (Q2), and sending described control circuit to, described control circuit receives described peak current and according to switching tube (Q1), switching tube (Q2) conducting or closure described in described peak current control.
Preferably, comprise sampling resistor (Rs1), sampling resistor (Rs2), diode (D3), diode (D4) at sample circuit described in the utility model; Described sampling resistor (Rs1) first end connects described switching tube (Q1) source electrode, described sampling resistor (Rs1) the second end ground connection; Described sampling resistor (Rs2) first end connects described switching tube (Q2) source electrode, described sampling resistor (Rs2) the second end ground connection; Described diode (D3) is anodal to be connected with described sampling resistor (Rs1) first end, and described diode (D3) negative pole is connected with described control circuit; Described diode (D4) is anodal to be connected with described sampling resistor (Rs2) first end, and described diode (D4) negative pole is connected with described control circuit.
Preferably, comprise operational amplifier (U1), operational amplifier (U2), resistance (Z1), resistance (Z2), resistance (Z3) at control circuit described in the utility model, a reference source, circuits for triggering, the negative pole of described operational amplifier (U1) is connected with the negative pole of described diode (D1) by described resistance (Z1), and by described resistance Z2 ground connection, the positive pole of described operational amplifier (U1) connects described a reference source simultaneously; The negative pole of described operational amplifier (U2) connects the output of described operational amplifier (U1), and the positive pole of described operational amplifier (U2) connects the negative pole of described diode (D3), and simultaneously by resistance (Z3) ground connection; The output of described operational amplifier (U2) is connected with described circuits for triggering.
Preferably, comprise rest-set flip-flop at circuits for triggering described in the utility model, clock signal, drives,
Described rest-set flip-flop R end is connected with the output of described operational amplifier (U2), described rest-set flip-flop S end is connected with described clock signal, and described rest-set flip-flop Q end is connected with described switching tube (Q1) grid and described switching tube (Q2) grid by described driving.
Preferably, also comprise resistance (Z4), electric capacity (C1) at control circuit described in the utility model, described resistance (Z4) first end is connected with the output of described operational amplifier (U1), the second end of described resistance (Z4) is connected with the negative pole of described operational amplifier (U1) by described electric capacity (C1), composition compensating network.
Preferably, in the utility model, at least described sample circuit and control circuit are integrated in a chip.
Preferably, connect described switching tube (Q1) drain electrode at sample circuit described in the utility model simultaneously, switching tube (Q2) drain electrode, and described control circuit also comprises a PWM device, for exporting high and low level signal.
Preferably, be configured at control circuit described in the utility model, in the time of PWM device output high level signal, described control circuit is opened described switching tube (Q1), described switching tube (Q2), and described control circuit receives described sample circuit feedback signal; In the time of PWM device output low level signal, described control circuit cuts out described switching tube (Q1), described switching tube (Q2), and described control circuit does not receive described sample circuit feedback signal.
Preferably, in the utility model, at least described sample circuit and control circuit are integrated in a chip.
Preferably, comprise first mirror image current source circuit at sample circuit described in the utility model, the second image current source circuit, described first mirror image current source circuit is configured to certain proportion image copying the flow through electric current of described switching tube (Q1) output; Described the second mirror current source Circnit Layout is the electric current of described switching tube (Q2) that flow through with certain proportion image copying, and output.
Preferably, also comprise sampling resistor (Rs3) at sample circuit described in the utility model, diode (D3), diode (D4), the output of described first mirror image current source circuit is connected with described diode (D3) is anodal; The output of described the second image current source circuit is connected with described diode (D4) is anodal; Described sampling resistor (Rs3) first end is connected with described diode (D3), described diode (D4) negative pole simultaneously, described sampling resistor (Rs3) the second end ground connection; Described control circuit is connected with described sample circuit by described sampling resistor (Rs3) first end.
Preferably, at sample circuit described in the utility model, control circuit, switching tube (Q1), switching tube (Q2) are integrated in a chip.
Preferably, connect the positive pole of described diode (D2) at the second end of input power described in the utility model (V1) by an inductance (L2), described inductance (L1) and described inductance (L2) are coupled or are independent mutually.
Preferably, provided by electronic transformer or linear transformer at input power described in the utility model (V1).
Adopt after technique scheme, compared with prior art, there is following beneficial effect:
1. improve LED drive circuit efficiency;
2. reduce circuit volume and components and parts number;
3. reduce costs and design difficulty.
Brief description of the drawings
Fig. 1 is the LED circuit system block diagram that uses rectifier bridge in prior art;
Fig. 2 be in prior art, use single inductance without bridge circuit schematic diagram;
Fig. 3 be in prior art, use coupling inductance without bridge circuit schematic diagram;
Fig. 4 is the schematic diagram of the utility model the first embodiment LED drive circuit;
Working waveform figure when Fig. 5 is the use electronic transformer of the utility model the first embodiment;
Fig. 6 is the schematic diagram of the utility model the second embodiment LED drive circuit;
Fig. 7 is the schematic diagram of the utility model the 3rd embodiment LED drive circuit.
Embodiment
Further set forth advantage of the present utility model below with reference to specific embodiment and accompanying drawing.
As shown in Figure 4, be the schematic diagram of the utility model the first embodiment LED drive circuit.
The utility model LED drive circuit has comprised without bridge circuit and peak value control circuit.Switching tube Q1, switching tube Q2, input power V1, diode D1, diode D2, inductance L 1 and output capacitance C are comprised without bridge circuit.Input power V1 is low-voltage AC, and input power V1 first end connects the positive pole of diode D1 by inductance L 1, and the negative pole of diode D1 is connected with output capacitance C first end.This input power V1 the second end connects the positive pole of diode D2, and the negative pole of this diode D2 is connected with output capacitance C first end.The drain electrode of switching tube Q1 is connected with diode D1 is anodal, and the drain electrode of switching tube Q2 is connected with diode D2 is anodal.
Peak value control circuit has comprised sample circuit and control circuit.Sample circuit is made up of sampling resistor Rs1, sampling resistor Rs2, diode D3, diode D4.The source electrode of switching tube Q1 is connected with output capacitance C the second end by a sampling resistor Rs1, and the source electrode of switching tube Q2 is connected with output capacitance C the second end by a sampling resistor Rs2.Sampling resistor Rs1, sampling resistor Rs2 are respectively the sampling resistor of switching tube Q1 and switching tube Q2, because needing in circuit that the electric current of switching tube Q1 and switching tube Q2 is sampled, the simplest mode is exactly the sampling resistor of directly connecting, again because switching tube Q1 and switching tube Q2 can be according to positive and negative being used alternatingly of input power V1 voltage, thus switching tube Q1 and switching tube Q2 all need the sampling resistor of connecting.Current diode D1, diode D2 adopt Schottky diode conventionally, and switching tube Q1, switching tube Q2 use low pressure field effect transistor.
Control circuit, has comprised circuits for triggering, operational amplifier U1, operational amplifier U2, resistance Z1, resistance Z2 and resistance Z3.Wherein circuits for triggering have comprised rest-set flip-flop, driving, clock signal.The grid of switching tube Q1, switching tube Q2 connects the Q end of rest-set flip-flop simultaneously by driving, the source electrode of Simultaneous Switching pipe Q1 connects the positive pole of diode D3, the source electrode of switching tube Q2 connects the positive pole of diode D4, the positive terminal of the negative pole concatenation operation amplifier U2 of diode D3, diode D4.Like this, the sample rate current of switching tube Q1 and switching tube Q2 directly feeds back in control circuit through diode D3 or diode D4.Diode D3 and diode D4 are for preventing that electric current reverse reflux in control circuit is to switching tube Q1 and switching tube Q2.The output of operational amplifier U2 is connected with the R of rest-set flip-flop end, and the S end of this rest-set flip-flop connects a clock signal, and the positive terminal of this operational amplifier U2 is by a resistance Z3 ground connection, and its negative pole end connects the output of an operational amplifier U1.The output of operational amplifier U1 is connected to the negative pole end of operational amplifier U1 by a resistance Z4 and a capacitor C 1, then by a resistance Z2 ground connection.The negative pole end of this operational amplifier U1 is also connected with output capacitance C first end by a resistance Z1 simultaneously, and its positive terminal connects an a reference source.Output capacitance C first end connects out-put supply Vo positive pole, and its second end connects out-put supply Vo negative pole.Out-put supply Vo can directly connect LED light source in this embodiment, or connects LED light source by a constant-current drive circuit again.Switching tube Q1, switching tube Q2 are subject to the control of rest-set flip-flop simultaneously, and the voltage of out-put supply Vo, through resistance Z1 and resistance Z2 dividing potential drop, feeds back to the negative pole end of operational amplifier U1, and resistance Z4 and capacitor C 1 form compensating network simultaneously, are designed to low-frequency filter characteristics.The output valve of operational amplifier U1 is the reference value as the current peak of switching tube Q1 and switching tube Q2 by operational amplifier U2, the feedback voltage of sampling resistor Rs1 and sampling resistor Rs2 is sent to operational amplifier U2, resistance Z3, as bleeder resistance, avoids operational amplifier U2 positive terminal place charge accumulated.In the time that the electric current of sampling resistor Rs1 or sampling resistor Rs2 process is enough large, positive terminal voltage at operational amplifier U2 exceedes negative pole end voltage, operational amplifier U2 is just output as, by rest-set flip-flop cut-off switch pipe Q1 and switching tube Q2, clock signal is as start signal, make switching tube Q1 and switching tube Q2 timing conducting by rest-set flip-flop, what it may occur to persons skilled in the art that is the operating frequency that can change circuit by the frequency of change clock signal.
As shown in Figure 5, the working waveform figure while using electronic transformer for the utility model the first embodiment, because electronic transformer adopts high frequency square wave output, the set of frequency of circuit is the output frequency higher than electronic transformer.When input power V1 voltage is for just, when switching tube Q1 and switching tube Q2 conducting, electric current is from input power V1 first end process inductance L 1, switching tube Q1, switching tube Q2(comprises the parasitic diode in its body) return to input power V1 the second end, at this moment the electric current of inductance L 1 is linear rises, in the time that switching tube Q1 and switching tube Q2 close, because the electric current of inductance L 1 can not suddenly change, electric current is from the first end process inductance L 1 of input power V1, diode D1, out-put supply Vo, switching tube Q2(endophyte diode) return to input power V1, now inductive current is linear decline.In like manner, in the time that input power V1 voltage is negative value, when switching tube Q1 and switching tube Q2 conducting, the electric current of inductance L 1 is linear to rise, but direction and the voltage of input power V1 be on the occasion of time contrary; In the time that switching tube Q1 and switching tube Q2 close, the electric current of inductance L 1 is linear to decline, but direction and the voltage of input power V1 be on the occasion of time contrary.Such setting compared with prior art, can effectively be saved unnecessary device, has improved conversion efficiency, has reduced temperature rise.In the time using electronic transformer, preferred, the utility model can adopt fixed frequency peak current control circuit, obtains normal vibration output in order to ensure electronic transformer internal drive magnetic saturation, and inductive current must reach certain peak value.Adopt peak current control circuit can realize easily the peaked control of inductive current.In the time that switching tube Q1 and switching tube Q2 Current rise arrive maximum to design load or duty ratio, switching tube Q1 and switching tube Q2 disconnect.
As shown in Figure 6, be the circuit diagram of the utility model the second embodiment, the LED drive circuit of the utility model the second embodiment comprises without bridge circuit, control circuit and sample circuit.The grid of switching tube Q1 is connected control circuit with the grid of switching tube Q2, and the drain electrode of Simultaneous Switching pipe Q1 is connected sample circuit with the drain electrode of switching tube Q2.Sample circuit sends the current signal sampling to control circuit.In control circuit, be also provided with a PWM(pulse width modulation) device, this PWM device can produce pwm signal, and control circuit is by pwm signal control sample circuit and switching tube Q1, switching tube Q2.Because sampling resistor can increase the loss of circuit in large electric current application, therefore, can utilize the conducting resistance of switching tube Q1 and switching tube Q2 to carry out the detection of electric current for this situation.Because switching tube Q1 and switching tube Q2 have certain conducting resistance when the conducting, and resistance is less, the drain voltage by sample circuit can be switching tube Q1 and switching tube Q2 conducting time by sample circuit sampling feedback to control circuit.The drain voltage of switching tube Q1 and switching tube Q2 is the waveform of a HF switch, and in the time of conducting, its value equals the product of electric current and conducting resistance, and in the time closing, equals the magnitude of voltage of out-put supply Vo.So sample circuit need to, in conjunction with pwm signal, when pwm signal is high level, be sampled to switching tube Q1 and switching tube Q2 when that is to say switching tube Q1, Q2 conducting.When pwm signal is when being low level, that is to say that when switching tube Q1, Q2 disconnect, sample circuit does not feed back drain voltage.Similarly, in order to reduce chip port, improve level of integrated system, sample circuit and control circuit can be integrated in a chip and make a chip, can also improve like this precision and the interference of avoiding other signals of sampling simultaneously.
As shown in Figure 7, be the circuit diagram of the utility model the 3rd embodiment, in the present embodiment, LED drive circuit of the present utility model comprises without bridge circuit and peak value control circuit.Described peak value control circuit has comprised sample circuit and control circuit.Sample circuit is made up of image current source circuit and diode D3, diode D4 and sampling resistor Rs3.Adopt image current source circuit the electric current of flow through switching tube Q1 and switching tube Q2 with certain proportion mirror image out.Image current source circuit comprises the first mirror image circuit and the second mirror image circuit.The first mirror image circuit is for the electric current of image copying switching tube Q1 drain electrode, and the second mirror image circuit is for the electric current of image copying switching tube Q2 drain electrode.First mirror connects the positive pole of diode D3 as circuit output end, the second mirror image circuit output connects the positive pole of diode D4, and this diode D3 negative pole is connected the first end of sampling resistor Rs3, the second end ground connection of sampling resistor Rs3 with this diode D4 negative pole.Diode D3 negative pole is also connected control circuit with diode D4 negative pole simultaneously, by the current feedback sampling in control circuit.Image current utilizes mirror image circuit to sample, can effectively reduce the loss on sample circuit Rs3, because can design little more much through the electric current of switching tube Q1 and switching tube Q2 than actual flow.Equally also can will comprise the sample circuit of mirror image circuit, switching tube Q1 and switching tube Q2, control circuit is incorporated into and in chip piece, makes an integrated chip.
Should be noted that, embodiment of the present utility model has preferably implementation, and not the utility model is done to any type of restriction, any person skilled in art of being familiar with may utilize the technology contents of above-mentioned announcement to change or be modified to the effective embodiment being equal to, in every case do not depart from the content of technical solutions of the utility model, any amendment or equivalent variations and the modification above embodiment done according to technical spirit of the present utility model, all still belong in the scope of technical solutions of the utility model.
Claims (15)
1. a LED drive circuit, comprises,
Switching tube (Q1), switching tube (Q2), input power (V1), diode (D1), diode (D2), inductance (L1),
Described switching tube (Q1) drain electrode is connected with described diode (D1) is anodal, and described switching tube (Q1) drain electrode is connected with the first end of described input power (V1) by inductance (L1);
Described switching tube (Q2) drain electrode is connected with described diode (D2) is anodal, and described switching tube (Q2) drain electrode is connected with the second end of described input power (V1) by inductance (L1);
It is characterized in that,
Also comprise peak value control circuit, described peak value control circuit be configured to the to sample peak current of described switching tube (Q1) and described switching tube (Q2), and by switching tube (Q1) and (Q2) conducting of described switching tube or closure described in the grid control of described switching tube (Q1) and described switching tube (Q2).
2. LED drive circuit as claimed in claim 1, is characterized in that, described peak value control circuit comprises sample circuit, control circuit,
Described sample circuit be configured to the to sample peak current of described switching tube (Q1) and described switching tube (Q2), and sending described control circuit to, described control circuit receives described peak current and according to switching tube (Q1), switching tube (Q2) conducting or closure described in described peak current control.
3. LED drive circuit as claimed in claim 2, is characterized in that, described sample circuit comprises sampling resistor (Rs1), sampling resistor (Rs2), diode (D3), diode (D4);
Described sampling resistor (Rs1) first end connects described switching tube (Q1) source electrode, described sampling resistor (Rs1) the second end ground connection;
Described sampling resistor (Rs2) first end connects described switching tube (Q2) source electrode, described sampling resistor (Rs2) the second end ground connection;
Described diode (D3) is anodal to be connected with described sampling resistor (Rs1) first end, and described diode (D3) negative pole is connected with described control circuit;
Described diode (D4) is anodal to be connected with described sampling resistor (Rs2) first end, and described diode (D4) negative pole is connected with described control circuit.
4. LED drive circuit as claimed in claim 3, is characterized in that, described control circuit comprises operational amplifier (U1), operational amplifier (U2), resistance (Z1), resistance (Z2), resistance (Z3), a reference source, and circuits for triggering,
The negative pole of described operational amplifier (U1) is connected with the negative pole of described diode (D1) by described resistance (Z1), and simultaneously by described resistance Z2 ground connection, the positive pole of described operational amplifier (U1) connects described a reference source;
The negative pole of described operational amplifier (U2) connects the output of described operational amplifier (U1), and the positive pole of described operational amplifier (U2) connects the negative pole of described diode (D3), and simultaneously by resistance (Z3) ground connection;
The output of described operational amplifier (U2) is connected with described circuits for triggering.
5. LED drive circuit as claimed in claim 4, is characterized in that, described circuits for triggering comprise rest-set flip-flop, and clock signal drives,
Described rest-set flip-flop R end is connected with the output of described operational amplifier (U2), described rest-set flip-flop S end is connected with described clock signal, and described rest-set flip-flop Q end is connected with described switching tube (Q1) grid and described switching tube (Q2) grid by described driving.
6. LED drive circuit as claimed in claim 4, is characterized in that, described control circuit also comprises resistance (Z4), electric capacity (C1),
Described resistance (Z4) first end is connected with the output of described operational amplifier (U1), and the second end of described resistance (Z4) is connected with the negative pole of described operational amplifier (U1) by described electric capacity (C1), composition compensating network.
7. LED drive circuit as claimed in claim 6, is characterized in that, at least described sample circuit and control circuit are integrated in a chip.
8. LED drive circuit as claimed in claim 2, is characterized in that, described sample circuit connects described switching tube (Q1) drain electrode simultaneously, switching tube (Q2) drain electrode, and described control circuit also comprises a PWM device, for exporting high and low level signal.
9. LED drive circuit as claimed in claim 8, is characterized in that, described control circuit is configured to,
In the time of PWM device output high level signal, described control circuit is opened described switching tube (Q1), described switching tube (Q2), and described control circuit receives described sample circuit feedback signal;
In the time of PWM device output low level signal, described control circuit cuts out described switching tube (Q1), described switching tube (Q2), and described control circuit does not receive described sample circuit feedback signal.
10. LED drive circuit as claimed in claim 9, is characterized in that, at least described sample circuit and control circuit are integrated in a chip.
11. LED drive circuits as claimed in claim 2, is characterized in that, described sample circuit comprises first mirror image current source circuit, the second image current source circuit,
Described first mirror image current source circuit is configured to certain proportion image copying the flow through electric current of described switching tube (Q1) output;
Described the second mirror current source Circnit Layout is the electric current of described switching tube (Q2) that flow through with certain proportion image copying, and output.
12. LED drive circuits as claimed in claim 11, is characterized in that, described sample circuit also comprises sampling resistor (Rs3), diode (D3), and diode (D4),
The output of described first mirror image current source circuit is connected with described diode (D3) is anodal;
The output of described the second image current source circuit is connected with described diode (D4) is anodal;
Described sampling resistor (Rs3) first end is connected with described diode (D3), described diode (D4) negative pole simultaneously, described sampling resistor (Rs3) the second end ground connection;
Described control circuit is connected with described sample circuit by described sampling resistor (Rs3) first end.
13. LED drive circuits as claimed in claim 12, is characterized in that, described sample circuit, control circuit, and switching tube (Q1), switching tube (Q2) are integrated in a chip.
14. LED drive circuits as described in claim 1-13 any one, it is characterized in that, the second end of described input power (V1) connects the positive pole of described diode (D2) by an inductance (L2), described inductance (L1) and described inductance (L2) are coupled or are independent mutually.
15. LED drive circuits as described in claim 1-13 any one, is characterized in that, described input power (V1) is provided by electronic transformer or linear transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320864033.1U CN203691696U (en) | 2013-12-25 | 2013-12-25 | Bridgeless LED drive circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320864033.1U CN203691696U (en) | 2013-12-25 | 2013-12-25 | Bridgeless LED drive circuit |
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| Publication Number | Publication Date |
|---|---|
| CN203691696U true CN203691696U (en) | 2014-07-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320864033.1U Expired - Fee Related CN203691696U (en) | 2013-12-25 | 2013-12-25 | Bridgeless LED drive circuit |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104149647A (en) * | 2014-08-19 | 2014-11-19 | 青岛盛嘉信息科技有限公司 | Brake method based on DSP control |
| CN104754792A (en) * | 2013-12-25 | 2015-07-01 | 欧普照明股份有限公司 | Bridgeless LED (Light Emitting Diode) driving circuit |
-
2013
- 2013-12-25 CN CN201320864033.1U patent/CN203691696U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104754792A (en) * | 2013-12-25 | 2015-07-01 | 欧普照明股份有限公司 | Bridgeless LED (Light Emitting Diode) driving circuit |
| CN104754792B (en) * | 2013-12-25 | 2018-03-06 | 欧普照明股份有限公司 | One kind is without bridge LED drive circuit |
| CN104149647A (en) * | 2014-08-19 | 2014-11-19 | 青岛盛嘉信息科技有限公司 | Brake method based on DSP control |
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