CN104427702A - Ripple compensation circuit, BUCK type LED (light emitting diode) driver and lamp - Google Patents
Ripple compensation circuit, BUCK type LED (light emitting diode) driver and lamp Download PDFInfo
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- CN104427702A CN104427702A CN201310399726.2A CN201310399726A CN104427702A CN 104427702 A CN104427702 A CN 104427702A CN 201310399726 A CN201310399726 A CN 201310399726A CN 104427702 A CN104427702 A CN 104427702A
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Abstract
The invention relates to a ripple compensation circuit, a BUCK type LED (light emitting diode) driver and a lamp. The ripple compensation circuit comprises a BUCK converting circuit, a ripple current detecting module, a ripple current regulating module and a control circuit, wherein the BUCK converting circuit is connected with a power supply and an LED lamp, the ripple current detecting module is connected with the BUCK converting circuit, the ripple current regulating module is connected with the ripple current detecting module, the control circuit is connected with the ripple current regulating module and the BUCK converting circuit, the ripple current detecting module is used for detecting ripple current in a circuit, the ripple current regulating module is used for regulating the ripple current, and the control circuit is used for maintaining the current constancy. The inductor ripple current in the circuit can be compensated, in addition, the service life of the lamp is prolonged, the stability is higher, and the size is smaller.
Description
Technical field
The present invention relates to compensating circuit, particularly relate to ripple compensation circuit, BUCK type LED driver and light fixture.
Background technology
In traditional LED drive power, BUCK circuit rear class adopts LC filtering, and during driving power work, its output voltage is made up of small ripple and larger DC component.Current-voltage characteristic due to LED is nonlinear, as long as forward voltage changes, all can cause the change of larger forward current, and the brightness of LED and size of current closely related.When power drives LED works, this ripple voltage will cause ripple current larger on LED.The filter capacitor (being generally electrochemical capacitor) increased in lc circuit can reduce the ripple current of LED.But along with the increase of capacitance, cause power volume and weight to increase, affect the miniaturization of power supply and integrated, the more important thing is, the electrochemical capacitor life in practical application becomes the main cause limiting the LED drive power life-span.Under actual LED illumination applied environment, the life-span of electrochemical capacitor is less than 10,000 hours usually, forms sharp contrast, become the short slab of LED lamp reliability with the theoretical long-life (100,000 hours) of LED.
Summary of the invention
The technical problem to be solved in the present invention is the deficiency overcoming the existence of above-mentioned prior art, and a kind of ripple compensation circuit, BUCK type LED driver and light fixture are proposed, it can reduce the ripple current in circuit and the volume keeping power supply less, can also extend the life-span of light fixture.
For solving the problems of the technologies described above, the present invention proposes a kind of ripple compensation circuit of BUCK type LED driver, it comprises: ripple current detection module, and it is for the ripple current in testing circuit, and it comprises: first input end, the second input, the first output and the second output; And ripple current adjusting module, it is for adjusting ripple current, it comprises: first input end, the second input and output, the first input end of ripple current adjusting module connects the first output of ripple current detection module, second input of ripple current adjusting module connects the second output of ripple current detection module, and the output of ripple current adjusting module connects the first input end of ripple current detection module.First resistance, second resistance, first operational amplifier, first electric capacity and the second electric capacity, first resistance is connected between the first input end of ripple current detection module and the end of oppisite phase of the first operational amplifier, second resistance is connected between the second input of ripple current detection module and the in-phase end of the first operational amplifier, one end of first electric capacity connects the in-phase end of the first operational amplifier, the other end ground connection of the first electric capacity, second output of ripple current detection module connects the other end of the first electric capacity, between the end of oppisite phase that second electric capacity is connected to the first operational amplifier and the first output.
Preferably, the first electric capacity and the second electric capacity are solid capacitance.
Preferably, ripple current adjusting module comprises ripple amplifying unit and the first switching tube, ripple amplifying unit comprises first input end, second input, first output and the second output, first switching tube comprises control end, input and output, the first input end of ripple amplifying unit and the second input connect first input end and second input of ripple current adjusting module respectively, first output of ripple amplifying unit connects the control end of the first switching tube, second output of ripple amplifying unit connects the input of the first switching tube, the output of the first switching tube connects the output of ripple current adjusting module.
Preferably, ripple amplifying unit comprises the 3rd resistance, 4th resistance, 5th resistance, 6th resistance and the second operational amplifier, 3rd resistance is connected between the in-phase end between the first input end of ripple amplifying unit and the second operational amplifier, 4th resistance is connected between the end of oppisite phase between the second input of ripple amplifying unit and the second operational amplifier, between the second input that 5th resistance is connected to ripple amplifying unit and the second output, 6th resistance is connected between the end of oppisite phase of the second operational amplifier and the second output of ripple amplifying unit.
Preferably, the first switching tube is triode, and the base stage of triode is the control end of the first switching tube, the input of the current collection of triode very the first switching tube, the output of the transmitting of triode very the first switching tube.
The present invention also proposes a kind of BUCK type LED driver, BUCK translation circuit, it is for converting input voltage, it comprises first input end, the second input, the first output, the second output and an inductance, the first input end of BUCK translation circuit connects power supply, second output of BUCK translation circuit connects one end of load, and one end of inductance connects the first output of BUCK translation circuit, and the other end of inductance connects the second output of BUCK translation circuit; Control circuit, it is for keeping the constant of electric current, and it comprises sampling end and output, and the sampling end of control circuit connects the other end of load, and the output of control circuit connects the second input of BUCK translation circuit; And ripple compensation circuit as above, the first input end of the ripple current detection module of ripple compensation circuit connects the first output of BUCK translation circuit, second input of the ripple current detection module of ripple compensation circuit connects the second output of BUCK translation circuit, and the output of the ripple current adjusting module of ripple compensation circuit connects the first output of BUCK translation circuit.
Preferably, BUCK translation circuit comprises: the 5th resistance, the 6th resistance, second switch pipe, inductance and fly-wheel diode; Between the second input that 5th resistance and the 6th resistance are connected on BUCK translation circuit successively and first input end, second switch pipe comprises control end, input and output, the control end of second switch pipe connects the junction of the 5th resistance and the 6th resistance, the input of second switch pipe connects the first input end of BUCK translation circuit, the output of second switch pipe connects the first output of BUCK translation circuit, the negative electrode of fly-wheel diode connects the output of second switch pipe, the plus earth of fly-wheel diode.
Preferably, second switch pipe is metal-oxide-semiconductor, and the grid of metal-oxide-semiconductor is the control end of switching tube, and the source electrode of metal-oxide-semiconductor is the input of switching tube, and the drain electrode of metal-oxide-semiconductor is the output of switching tube.
The present invention also proposes a kind of light fixture, and it comprises described BUCK type LED driver.
Compared with prior art, the present invention has following beneficial effect: ripple compensation circuit of the present invention, BUCK type LED driver and light fixture, the functional circuit consisted of operational amplifier composition differential integrator circuit and triode is to the compensation of the electric current of inductance ripple, the life-span of product can be made longer, stability is better, and keeps less volume.
Accompanying drawing explanation
Fig. 1 is the electrical block diagram of BUCK type LED driver ripple compensation circuit.
Wherein, description of reference numerals is as follows: ripple compensation circuit 1 ripple current detection module 11 first resistance R1 second resistance R2 first operational amplifier U1 first electric capacity C1 second electric capacity C2 ripple current adjusting module 12 ripple amplifying unit 121 the 3rd resistance R3 the 4th resistance R4 the 5th resistance R5 the 6th resistance R6 second operational amplifier U2 first switching tube Q1 BUCK translation circuit 2 the 5th resistance R5 the 6th resistance R6 second switch pipe Q2 inductance L 1 sustained diode 3 control circuit 3 load 4 first LED D1 second LED D2.
Embodiment
In order to further illustrate principle of the present invention and structure, existing by reference to the accompanying drawings to a preferred embodiment of the present invention will be described in detail.
ripple compensation circuit embodiments
The present invention proposes a kind of ripple compensation circuit, and it comprises: ripple current detection module 11 and ripple current adjusting module 12.Ripple current detection module 11 is for the ripple current in testing circuit, and ripple current adjusting module 12 is for adjusting ripple current.
Ripple current detection module 11 comprises: first input end, the second input, the first output and the second output.Ripple current adjusting module 12 comprises: first input end, the second input and output.The first input end of ripple current adjusting module 12 connects the first output of ripple current detection module 11, second input of ripple current adjusting module 12 connects the second output of ripple current detection module 11, and the output of ripple current adjusting module 12 connects the first input end of ripple current detection module 11.
Ripple current detection module 11 comprises: the first resistance R1, the second resistance R2, the first operational amplifier U1, the first electric capacity C1 and the second electric capacity C2.First resistance R1 is connected between the first input end of ripple current detection module 11 and the end of oppisite phase of the first operational amplifier U1.Second resistance R2 is connected between the second input of ripple current detection module 11 and the in-phase end of the first operational amplifier U1.One end of first electric capacity C1 connects the in-phase end of the first operational amplifier U1, the other end ground connection of the first electric capacity C1, and the second output of ripple current detection module 11 connects the other end of the first electric capacity C1.Second electric capacity C2 is connected between the end of oppisite phase of the first operational amplifier U1 and the first output of ripple current detection module 11.
Ripple current adjusting module 12 comprises ripple amplifying unit 121 and the first switching tube Q1.Ripple amplifying unit 121 comprises first input end, the second input, the first output and the second output.First switching tube Q1 comprises control end, input and output.The first input end of ripple amplifying unit 121 and the second input connect first input end and second input of ripple current adjusting module 12 respectively.First output of ripple amplifying unit 121 connects the control end of the first switching tube Q1, and the second output of ripple amplifying unit 121 connects the input of the first switching tube Q1.The output of the first switching tube Q1 connects the output of ripple current adjusting module 12.
Ripple amplifying unit 121 comprises the 3rd resistance R3, the 4th resistance R4, the 5th resistance R5, the 6th resistance R6 and the second operational amplifier U2.3rd resistance R3 is connected between the in-phase end between the first input end of ripple amplifying unit 121 and the second operational amplifier U2.4th resistance R4 is connected between the end of oppisite phase between the second input of ripple amplifying unit 121 and the second operational amplifier U2.5th resistance R5 is connected between the second input of ripple amplifying unit 121 and the input of the first switching tube Q1.6th resistance R6 is connected between the end of oppisite phase of the second operational amplifier U2 and the input of the first switching tube Q1.The output of the first switching tube Q1 connects the output of ripple current adjusting module 12.This ripple current adjusting module 12 is all use basic electronic component, is easy to realize, has actual application value.
In the present embodiment, the first electric capacity C1 and the second electric capacity C2 is solid capacitance, such as tantalum electric capacity etc.Solid capacitance is the Novel long-life type electric capacity that energy density is less, so just can replace electrochemical capacitor, namely can ensure the life-span of LED lamp, also makes power supply keep miniaturized and integrated.
In the present embodiment, the first switching tube Q1 is triode, and the base stage of triode is the control end of the first switching tube Q1, the input of the current collection of triode very the first switching tube Q1, the output of the transmitting of triode very the first switching tube Q1.In other embodiments, also triode can be replaced with metal-oxide-semiconductor.
The compensation of this ripple compensation circuit 1 by adopting the functional circuit of solid capacitor, operational amplifier composition differential integrator circuit and triode composition can realize the electric current of inductance ripple, and stability is better, is easier to realize.
bUCK type LED driver embodiment
The present invention also proposes a kind of BUCK type Switching Power Supply, and it comprises: ripple compensation circuit 1, BUCK translation circuit 2 and control circuit 3 as above.
Ripple compensation circuit 1 is for compensating the ripple current in circuit, and BUCK translation circuit 2 is for converting input voltage, and control circuit 3 is for keeping the constant of electric current.
BUCK translation circuit 2 comprises first input end, the second input, the first output and the second output.Control circuit 3 comprises sampling end and output.The first input end of BUCK translation circuit 22 connects power supply, and the second output of BUCK translation circuit 22 connects one end of load.The first input end of the ripple current detection module 11 of ripple compensation circuit 1 connects the first output of BUCK translation circuit 2, second input of the ripple current detection module 11 of ripple compensation circuit 1 connects the second output of BUCK translation circuit 2, and the output of the ripple current adjusting module 12 of ripple compensation circuit 1 connects the first output of BUCK translation circuit 2.The sampling end of control circuit 3 connects the other end of load 4, and the output of control circuit 3 connects the second input of BUCK translation circuit 2.
BUCK translation circuit 2 comprises: the 5th resistance R5, the 6th resistance R6, second switch pipe Q2, inductance L 1, sustained diode 3 and inductance L 1.Between the second input that 5th resistance R5 and the 6th resistance R6 is connected on BUCK translation circuit 2 successively and first input end.Second switch pipe Q2 comprises control end, input and output, the control end of second switch pipe Q2 connects the junction of the 5th resistance R5 and the 6th resistance R6, the input of second switch pipe Q2 connects the first input end of BUCK translation circuit 2, and the output of second switch pipe Q2 connects the first output of BUCK translation circuit 2.One end of inductance L 1 connects the first output of BUCK translation circuit 2, and the other end of inductance L 1 connects the second output of BUCK translation circuit 2.The negative electrode of sustained diode 3 connects the output of second switch pipe Q2, the plus earth of sustained diode 3.
Control circuit, it is for keeping the constant of electric current, and it comprises sampling end and output.The sampling end of control circuit connects the other end of load, and the output of control circuit connects the second input of BUCK translation circuit.
In the present embodiment, control circuit is provided with the single-chip microcomputer (not shown) exporting pwm pulse.
In the present embodiment, second switch pipe Q2 is metal-oxide-semiconductor, and the grid of metal-oxide-semiconductor is the control end of switching tube, and the source electrode of metal-oxide-semiconductor is the input of switching tube, and the drain electrode of metal-oxide-semiconductor is the output of switching tube.In other embodiments, also metal-oxide-semiconductor can be replaced with triode.
After this BUCK type Switching Power Supply have employed ripple compensation circuit, its volume can be made less, and useful life is also longer.
light fixture embodiment
The present invention also proposes a kind of light fixture, and it comprises BUCK type Switching Power Supply as above and load 4.
Load 4 comprises: the first diode D1, the second diode D2, the 7th resistance R7 and the 8th resistance R8.Between one end that first diode D1 and the second diode D2 is connected on load 4 successively and the other end.7th resistance R7 and the 8th resistance R8 is in parallel, and one end of the 7th resistance R7 connects the negative electrode of LED, the other end ground connection of the 7th resistance R7.The sampling end of one end connection control circuit 3 of the 7th resistance R7.The output of control circuit 3 exports PWM, makes second switch pipe Q2 open or close, thus the current constant in holding circuit.
Operation principle of the present invention is described in detail below in conjunction with Fig. 1.
PWM is the adjustable pwm signal of duty ratio, and CS is sampled voltage input, by detecting the duty ratio of the voltage control PWM on the 7th resistance R7 and the 8th resistance R8, thus makes the constant current hold on LED.Meanwhile, by observing the voltage at inductance L 1 two ends detect ripple current, according to the relation of the voltage and current of inductance L 1, the voltage and current rate of change at the two ends of inductance L 1 is directly proportional, and this proportionality coefficient is inductance value L1.Ripple current detection module 11 forms differential integrator circuit by the first operational amplifier U1, the first resistance R1, the second resistance R2, the first electric capacity C1 and the second electric capacity C2, and the output voltage values of the first operational amplifier U1 and the ripple current of inductance L 1 are directly proportional.Second operational amplifier U2 and peripheral circuit thereof form ripple amplifying circuit together, amplify the variable quantity of the ripple current in inductance L 1, thus control the conducting state of triode Q1, realize the On current of triode Q1 to the compensation of inductance ripple current.Adjust the parameter of the peripheral circuit of the second operational amplifier U2, the full remuneration of the ripple current to inductance L 1 can be realized.
In other embodiments, the quantity of diode can be arranged according to the demand of practical matter.
Compared with prior art, the present invention has following beneficial effect: ripple compensation circuit of the present invention, BUCK type LED driver and light fixture, the functional circuit consisted of operational amplifier composition differential integrator circuit and triode is to the compensation of the electric current of inductance ripple, the life-span of product can be made longer, stability is better, and keeps less volume.
These are only better possible embodiments of the present invention, not limit the scope of the invention, all utilizations specification of the present invention and the change of the equivalent structure done by accompanying drawing content, be all included in protection scope of the present invention.
Claims (10)
1. a ripple compensation circuit for BUCK type LED driver, it is characterized in that, it comprises:
Ripple current detection module, it is for the ripple current in testing circuit, and it comprises: first input end, the second input, the first output and the second output; And
Ripple current adjusting module, it is for adjusting described ripple current, it comprises: first input end, the second input and output, the first input end of described ripple current adjusting module connects the first output of described ripple current detection module, second input of described ripple current adjusting module connects the second output of described ripple current detection module, and the output of described ripple current adjusting module connects the first input end of described ripple current detection module.
2. ripple compensation circuit as claimed in claim 1, it is characterized in that, described ripple current detection module comprises: the first resistance, second resistance, first operational amplifier, first electric capacity and the second electric capacity, described first resistance is connected between the first input end of described ripple current detection module and the end of oppisite phase of the first operational amplifier, described second resistance is connected between the second input of described ripple current detection module and the in-phase end of the first operational amplifier, one end of described first electric capacity connects the in-phase end of described first operational amplifier, the other end ground connection of described first electric capacity, second output of described ripple current detection module connects the other end of described first electric capacity, between the end of oppisite phase that described second electric capacity is connected to described first operational amplifier and the first output.
3. ripple compensation circuit as claimed in claim 2, described first electric capacity and the second electric capacity are solid capacitance.
4. ripple compensation circuit as claimed in claim 1, it is characterized in that, described ripple current adjusting module comprises ripple amplifying unit and the first switching tube, described ripple amplifying unit comprises first input end, second input, first output and the second output, described first switching tube comprises control end, input and output, the first input end of described ripple amplifying unit and the second input connect first input end and second input of described ripple current adjusting module respectively, first output of described ripple amplifying unit connects the control end of described first switching tube, second output of described ripple amplifying unit connects the input of described first switching tube, the output of described first switching tube connects the output of described ripple current adjusting module.
5. ripple compensation circuit as claimed in claim 4, it is characterized in that, described ripple amplifying unit comprises the 3rd resistance, 4th resistance, 5th resistance, 6th resistance and the second operational amplifier, described 3rd resistance is connected between the in-phase end between the first input end of described ripple amplifying unit and the second operational amplifier, described 4th resistance is connected between the end of oppisite phase between the second input of described ripple amplifying unit and the second operational amplifier, between the second input that described 5th resistance is connected to described ripple amplifying unit and the second output, described 6th resistance is connected between the end of oppisite phase of described second operational amplifier and the second output of described ripple amplifying unit.
6. ripple compensation circuit as claimed in claim 4, it is characterized in that, described first switching tube is triode, the base stage of described triode is the control end of described first switching tube, the input of very described first switching tube of current collection of described triode, the output of very described first switching tube of transmitting of described triode.
7. a BUCK type LED driver, is characterized in that,
BUCK translation circuit, it is for converting input voltage, it comprises first input end, the second input, the first output, the second output and an inductance, the first input end of described BUCK translation circuit connects power supply, second output of described BUCK translation circuit connects one end of load, one end of described inductance connects the first output of described BUCK translation circuit, and the other end of described inductance connects the second output of described BUCK translation circuit;
Control circuit, it is for keeping the constant of electric current, and it comprises sampling end and output, and the sampling end of described control circuit connects the other end of described load, and the output of described control circuit connects the second input of described BUCK translation circuit; And
Ripple compensation circuit as described in claim 1 to 6 any one, the first input end of the ripple current detection module of described ripple compensation circuit connects the first output of described BUCK translation circuit, second input of the ripple current detection module of described ripple compensation circuit connects the second output of described BUCK translation circuit, and the output of the ripple current adjusting module of described ripple compensation circuit connects the first output of described BUCK translation circuit.
8. BUCK type LED driver as claimed in claim 7, it is characterized in that, described BUCK translation circuit comprises: the 5th resistance, the 6th resistance, second switch pipe, inductance and fly-wheel diode, between the second input that described 5th resistance and the 6th resistance are connected on described BUCK translation circuit successively and first input end, described second switch pipe comprises control end, input and output, the control end of described second switch pipe connects the junction of described 5th resistance and the 6th resistance, the input of described second switch pipe connects the first input end of described BUCK translation circuit, the output of described second switch pipe connects the first output of described BUCK translation circuit, the negative electrode of described fly-wheel diode connects the output of described second switch pipe, the plus earth of described fly-wheel diode.
9. BUCK type LED driver as claimed in claim 8, it is characterized in that, described second switch pipe is metal-oxide-semiconductor, and the grid of described metal-oxide-semiconductor is the control end of described switching tube, the source electrode of described metal-oxide-semiconductor is the input of described switching tube, and the drain electrode of described metal-oxide-semiconductor is the output of described switching tube.
10. a light fixture, is characterized in that, it comprises the BUCK type LED driver as described in claim 7 to 9 any one.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310399726.2A CN104427702B (en) | 2013-09-04 | 2013-09-04 | Ripple compensation circuit, BUCK types LED driver and lamps and lanterns |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310399726.2A CN104427702B (en) | 2013-09-04 | 2013-09-04 | Ripple compensation circuit, BUCK types LED driver and lamps and lanterns |
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| Publication Number | Publication Date |
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| CN104427702A true CN104427702A (en) | 2015-03-18 |
| CN104427702B CN104427702B (en) | 2018-04-27 |
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| CN201310399726.2A Active CN104427702B (en) | 2013-09-04 | 2013-09-04 | Ripple compensation circuit, BUCK types LED driver and lamps and lanterns |
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| US20030231047A1 (en) * | 2002-06-13 | 2003-12-18 | Deaton Donald Joe | Pulse forming converter |
| CN1623269A (en) * | 2002-01-29 | 2005-06-01 | 英特赛尔美国股份有限公司 | Synthetic ripple regulator |
| CN101405671A (en) * | 2006-03-17 | 2009-04-08 | Nxp股份有限公司 | Supply circuit with ripple compensation |
| CN101471603A (en) * | 2007-12-27 | 2009-07-01 | 英业达股份有限公司 | DC-DC decompression converter and ripple improving circuit |
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2013
- 2013-09-04 CN CN201310399726.2A patent/CN104427702B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1623269A (en) * | 2002-01-29 | 2005-06-01 | 英特赛尔美国股份有限公司 | Synthetic ripple regulator |
| US20030231047A1 (en) * | 2002-06-13 | 2003-12-18 | Deaton Donald Joe | Pulse forming converter |
| CN101405671A (en) * | 2006-03-17 | 2009-04-08 | Nxp股份有限公司 | Supply circuit with ripple compensation |
| CN101471603A (en) * | 2007-12-27 | 2009-07-01 | 英业达股份有限公司 | DC-DC decompression converter and ripple improving circuit |
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| CN104427702B (en) | 2018-04-27 |
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