CN104768303B - LED drive control circuits - Google Patents
LED drive control circuits Download PDFInfo
- Publication number
- CN104768303B CN104768303B CN201510185449.4A CN201510185449A CN104768303B CN 104768303 B CN104768303 B CN 104768303B CN 201510185449 A CN201510185449 A CN 201510185449A CN 104768303 B CN104768303 B CN 104768303B
- Authority
- CN
- China
- Prior art keywords
- output
- voltage
- adjustment pipe
- output end
- circuit
- 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.)
- Active
Links
Landscapes
- Dc-Dc Converters (AREA)
Abstract
LED drive control circuits, including direct-flow input end, DC output end, output voltage feedback end, control loop and the power tube being connected with control loop；Also include the first reference voltage, linear voltage regulator, sampling resistor and adjustment pipe, the sampling resistor is connected between DC output end and adjustment pipe drain electrode, adjust pipe source electrode connection load LED, the control terminal of the adjustment pipe is connected with linear voltage regulator output end, and two inputs of the linear voltage regulator connect the common port and the first reference voltage of adjustment pipe and sampling resistor respectively；Second reference voltage is the divider resistance string being connected between direct-flow input end and ground.Rechargeable energy path turn-on and turn-off of the present invention by control input to output capacitance, realize transmission energy and supply on demand, the direct sampling to input direct voltage is realized into error amplifier using direct current input feedback, improves input response speed.
Description
Technical field
The invention belongs to IC design field, is related to Switching Power Supply, particularly a kind of LED drive controls circuit.
Background technology
With more and more harsh requirement of the development and LED drive power of high-voltage LED lamp bead to cost and volume, it is low into
This high voltage and constant current Linear Driving method obtains certain technology innovation and application in the past few years.But current Linear Driving side
All the time there is low reliability in method, require high matching to input voltage and output lamp bead, can not bear input and output voltage significantly
The shortcomings of fluctuation, Linear Driving method is hindered really applied in the production in enormous quantities and safety applications of LED illumination.
The content of the invention
To overcome the shortcomings of that existing LED drive chip is existing using linear voltage regulator decompression control, the invention discloses
A kind of LED drive controls circuit.
LED drive controls circuit of the present invention, including direct-flow input end, DC output end, output voltage feedback end, root
The power tube for controlling the control loop of power tube duty cycle of switching according to output voltage feedback end and being connected with control loop；
Also include the first reference voltage, linear voltage regulator LDO, sampling resistor R4 and adjustment pipe, the sampling resistor R4 to connect
Be connected between DC output end VOUT and adjustment pipe drain electrode, adjustment pipe source electrode connection load LED, the control terminal of the adjustment pipe with
Linear voltage regulator output end connects, and two inputs of the linear voltage regulator connect the public of adjustment pipe and sampling resistor respectively
End and the first reference voltage；The adjustment pipe is with loading LED common port as output voltage feedback end；The second benchmark electricity
Press to be connected to the divider resistance string between direct-flow input end and ground.
Preferably, the control loop includes logic drive circuit, PWM comparators, error amplifier, the second reference voltage
And current sampling circuit, two inputs of the error amplifier connect the second reference voltage and output voltage feedback respectively
End, two inputs of the PWM comparators connect the output end of error amplifier and current sampling circuit, the PWM respectively
The output end connection logic drive circuit of comparator, the output end connection power tube control terminal of the logic drive circuit.
Preferably, the current sampling circuit includes the current sampling resistor and electricity being connected between power tube source electrode and ground
Electric pressure converter is flowed, the input connection power tube source electrode of the current-to-voltage convertor, output end is as current sampling circuit
Output end.
Preferably, in addition to the protection circuit that is connected with logic drive circuit of output end.
The present invention is applied in booster type LED drive circuit by combining switched-capacitor circuit and linear constant current LDO, control
The rechargeable energy path turn-on and turn-off to output capacitance are inputted, LDO is realized to LED ripple-free constant current and fed-back output voltage
Switching capacity loop is given, transmission energy is realized and supplies on demand, is realized using direct current input feedback into error amplifier pair
The direct sampling of input direct voltage, improves input response speed.
Brief description of the drawings
Fig. 1 shows a kind of embodiment structural representation of the present invention.
Reference in Fig. 1 is entitled
VIN- direct-flow input end VOUT- DC output end M1- power tubes M2- adjustment pipe LDO- linear voltage regulators D1-
Sustained diode 2- load LED R1- the first divider resistance R2- the second divider resistance R3- current sampling resistors R4- samplings
Resistance COUT- output capacitance L- inductance VREF1- the first reference voltage V the second reference voltages of REF2-.
Embodiment
Below in conjunction with the accompanying drawings, the embodiment of the present invention is described in further detail.
LED drive controls circuit of the present invention, including direct-flow input end, DC output end, output voltage feedback end, root
The power tube for controlling the control loop of power tube duty cycle of switching according to output voltage feedback end and being connected with control loop；
Also include first reference voltage V REF, LDO, sampling resistor R4 and adjustment pipe M2, the sampling resistor is connected to directly
Flow between output end and adjustment pipe drain electrode, adjustment pipe source electrode connection load LED, the control terminal and LDO output ends of the adjustment pipe
Connection, two inputs of the LDO connect the common port and the first reference voltage of adjustment pipe and sampling resistor respectively；The tune
Homogeneous tube is with loading LED common port as output voltage feedback end；
The control loop includes logic drive circuit, PWM comparators, error amplifier, the second reference voltage and exchanged
Sample circuit, two inputs of the error amplifier connect the second reference voltage and output voltage feedback end respectively, described
Two inputs of PWM comparators connect the output end of error amplifier and alternating current sampling circuit respectively, the PWM comparators
Output end connects logic drive circuit, the output end connection power tube control terminal of the logic drive circuit.
Specifically, the current sampling circuit include being connected to current sampling resistor R3 between power tube source electrode and ground and
Current-to-voltage convertor, the input connection power tube source electrode of the current-to-voltage convertor, output end is as current sample electricity
The output end on road.
As shown in figure 1, system is divided into two large divisions, power tube M1 and output capacitance COUT form switching capacity controlling transmission
To the turn-on and turn-off of COUT energy pathways.LDO and adjustment pipe M2 is control LED output currents, and it is with exporting LED string string
The energy of connection, LDO and LED conductings comes from output capacitance COUT.The anode LED+, LED+ of M2 drain terminal connection load LED strip can
Reflect the size of energy on COUT electric capacity in real time, LDO positive input is connected with the first reference voltage.Adjusting pipe can be
PMOS or PNP pipe.
Using above-mentioned LDO and adjustment pipe control mode, eliminate and loaded caused by being fluctuated due to output voltage on LED
Fluctuation of pressure drop, make LED output currents more stable, while make the output voltage feedback terminal voltage for being input to Inner Control Loop
It is constant, reduce the power attenuation of control loop.
Using input voltage as 220V civil powers, output voltage is used to drive 28-60 LED light emitting diode, and output voltage exists
Tested exemplified by 80-200V excursion, the loss of control loop only changes 0.2W or so.It is considered that loss with
Output voltage is substantially unrelated.
Second reference voltage V REF2 is formed by the divider resistance string partial pressure being connected between direct-flow input end and ground, such as Fig. 1
Shown, the first divider resistance R1 and the second divider resistance R2 common port is divider node as the second reference voltage, the second base
Quasi- voltage is obtained by the voltage of direct-flow input end so that in booster type LED drive circuit, the change of input voltage can
Rapid feedback makes change of the control loop to input voltage adjust the change of power tube dutycycle in time to control loop.
Control loop preferably uses current feedback form, and the control loop includes logic drive circuit, PWM compares
Device, error amplifier, the second reference voltage and alternating current sampling circuit, two inputs of the error amplifier connect respectively
Two reference voltages and output voltage feedback end, two inputs of the PWM comparators connect error amplifier and exchanged respectively
The output end of sample circuit, the output end connection logic drive circuit of the PWM comparators, the output of the logic drive circuit
End connection power tube control terminal.Wherein the first reference voltage V REF1 can be produced by bandgap voltage reference output voltage partial pressure,
Partial pressure can use conventional electric resistance partial pressure form.
Preferably, protection circuit, such as overvoltage crowbar, overheating protection circuit etc. can also be set, it is defeated when detecting
Go out controls logic drive circuit to close power tube when voltage is excessive or power tube current is excessive.
Previously described each preferred embodiment for the present invention, if the preferred embodiment in each preferred embodiment
It is not obvious contradictory or premised on a certain preferred embodiment, each preferred embodiment can any stack combinations
Use, the design parameter in the embodiment and embodiment merely to clearly state the invention verification process of inventor, and
The scope of patent protection of the limitation present invention is not used to, scope of patent protection of the invention is still defined by its claims, all
It is the equivalent structure change made with the specification and accompanying drawing content of the present invention, similarly should be included in the protection model of the present invention
In enclosing.
Claims (2)
1.LED drive control circuits, including it is direct-flow input end, DC output end, output voltage feedback end, anti-according to output voltage
The control loop of feedback end control power tube duty cycle of switching and the power tube being connected with control loop；Characterized in that,
Also include the first reference voltage, linear voltage regulator, sampling resistor and adjustment pipe, the sampling resistor and be connected to direct current output
Between end and adjustment pipe drain electrode, adjustment pipe source electrode connection load LED, the control terminal and linear voltage regulator output end of the adjustment pipe
Connection, two inputs of the linear voltage regulator connect adjustment pipe and the common port of sampling resistor and the first benchmark electricity respectively
Pressure；The adjustment pipe is with loading LED common port as output voltage feedback end；Second reference voltage is by being connected to direct current
Divider resistance string partial pressure between input and ground is formed；
The control loop includes logic drive circuit, PWM comparators, error amplifier, the second reference voltage and current sample
Circuit, two inputs of the error amplifier connect the second reference voltage and output voltage feedback end, the PWM ratios respectively
Two inputs compared with device connect the output end of error amplifier and current sampling circuit, the output of the PWM comparators respectively
End connection logic drive circuit, the output end connection power tube control terminal of the logic drive circuit；
Also include the protection circuit that output end is connected with logic drive circuit.
2. LED drive controls circuit as claimed in claim 1, it is characterised in that the current sampling circuit includes being connected to
Current sampling resistor and current-to-voltage convertor between power tube source electrode and ground, the input of the current-to-voltage convertor connect
Connect power tube source electrode, output end of the output end as current sampling circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510185449.4A CN104768303B (en) | 2015-04-20 | 2015-04-20 | LED drive control circuits |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510185449.4A CN104768303B (en) | 2015-04-20 | 2015-04-20 | LED drive control circuits |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104768303A CN104768303A (en) | 2015-07-08 |
| CN104768303B true CN104768303B (en) | 2018-01-26 |
Family
ID=53649814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510185449.4A Active CN104768303B (en) | 2015-04-20 | 2015-04-20 | LED drive control circuits |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104768303B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107645803B (en) * | 2016-07-22 | 2019-04-12 | 得能创科有限公司 | A kind of omnipotent LED drive control device |
| CN106533140A (en) * | 2017-01-04 | 2017-03-22 | 西南应用磁学研究所 | High-efficiency magnetic tuning device drive circuit |
| CN107343344B (en) * | 2017-09-04 | 2019-11-22 | 矽力杰半导体技术(杭州)有限公司 | For the control circuit of LED driver, integrated circuit and LED driver |
| CN108513403B (en) * | 2018-04-17 | 2020-11-10 | 南京矽力微电子技术有限公司 | Control circuit and control method of power converter |
| CN111526641B (en) * | 2020-05-15 | 2022-06-10 | 深圳市洲明科技股份有限公司 | Back pressure self-adjusting method and device |
| CN111796621A (en) * | 2020-07-16 | 2020-10-20 | 山东超越数控电子股份有限公司 | Constant current source control method based on linear voltage stabilizer and constant current source circuit |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201681625U (en) * | 2010-05-21 | 2010-12-22 | 睿俐翔智通讯技术（北京）有限公司 | Multi-directional playing flat-panel mobile terminal |
| US8970200B2 (en) * | 2012-11-09 | 2015-03-03 | Apple Inc. | Systems and methods for light-load efficiency in displays |
| CN104470096B (en) * | 2014-11-26 | 2017-05-03 | 上海晶丰明源半导体股份有限公司 | LED driving circuit |
-
2015
- 2015-04-20 CN CN201510185449.4A patent/CN104768303B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN104768303A (en) | 2015-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104768303B (en) | LED drive control circuits | |
| CN103813587B (en) | A kind of LED drive circuit of numerical model analysis light modulation | |
| CN104780684A (en) | DC conversion LED drive circuit | |
| US9246381B2 (en) | Active power factor correction control circuit, chip and LED driving circuit thereof | |
| CN203872056U (en) | Direct-current power supply controlled by constant power | |
| CN103747561B (en) | Adjustment of load compensated switching power supply | |
| CN101500354A (en) | Light modulation control circuit for LED | |
| CN103079322B (en) | Closed loop light-emitting diode (LED) current control circuit and power-switching circuit | |
| CN103037597A (en) | Multi-channel LED (Light Emitting Diode) constant current control circuit and LED light source control system | |
| CN102098843A (en) | LED driving circuit with high accuracy and low power consumption | |
| CN203645873U (en) | Load regulation compensating circuit based on quasi-resonance LED constant current switch power supply | |
| CN104470096B (en) | LED driving circuit | |
| CN104302053A (en) | LED constant current source output detection control circuit and control method thereof | |
| CN102645948B (en) | Adjustable constant-current source | |
| CN203814023U (en) | PAM2842-based dimmable LED driver | |
| CN204681625U (en) | Input feedforward LED drive circuit | |
| US9977445B2 (en) | Low power standby mode for buck regulator | |
| CN102364569B (en) | A kind of linear constant current Drive and Control Circuit and light-emitting diode display thereof | |
| CN102404921B (en) | Output current adjustable intelligent constant current power supply device | |
| CN103457465B (en) | A kind of constant current/constant voltage DC-DC converting system with outside adjustable current-limiting function | |
| CN104470095B (en) | Ripple rejection LED drive circuit | |
| CN204697328U (en) | Booster type LED drive circuit | |
| CN105101539A (en) | Light-emitting diode (LED) constant current driving circuit | |
| CN107579648A (en) | A kind of inverse-excitation type switch power-supply and its control circuit | |
| CN204259229U (en) | Exchange the current mode LED fast start circuit driven |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C41 | Transfer of patent application or patent right or utility model | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20160426 Address after: 201204 Zhang Heng road Shanghai, Pudong New Area Zhangjiang hi tech Park Lane 666 No. 2 floor 504-511 room 5 Applicant after: Shanghai Bright Power Semiconductor Co.,Ltd. Address before: West high tech Zone Fucheng Road in Chengdu city of Sichuan province 610000 399 No. 6 Building 1 unit 10 floor No. 2 Applicant before: Chengdu Minchuang Science & Technology Co., Ltd. |
|
| CB02 | Change of applicant information |
Address after: 5 room 504-511, room 2, Lane 666, Zhang Heng Road, Pudong New Area, China (Shanghai) free trade zone, Shanghai, China () Applicant after: Shanghai semiconducto Limited by Share Ltd Address before: 201204 Zhang Heng road Shanghai, Pudong New Area Zhangjiang hi tech Park Lane 666 No. 2 floor 504-511 room 5 Applicant before: Shanghai Bright Power Semiconductor Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |