CN101998729A - Driving device and driving voltage regulation method - Google Patents
Driving device and driving voltage regulation method Download PDFInfo
- Publication number
- CN101998729A CN101998729A CN2009101696724A CN200910169672A CN101998729A CN 101998729 A CN101998729 A CN 101998729A CN 2009101696724 A CN2009101696724 A CN 2009101696724A CN 200910169672 A CN200910169672 A CN 200910169672A CN 101998729 A CN101998729 A CN 101998729A
- Authority
- CN
- China
- Prior art keywords
- voltage
- detecting
- reference voltage
- unit
- oxide
- 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.)
- Granted
Links
Images
Abstract
The invention relates to a driving device. The driving device is used for driving a plurality of loads to work and comprises a voltage regulation unit and a plurality of sensing units, wherein the voltage regulation unit is used for receiving direct current (DC) voltage to be electrified to work so as to output a driving voltage to the plurality of loads; the plurality of sensing units are used for sensing the total forward voltage of the plurality of corresponding loads respectively to generate a plurality of corresponding sensing voltages and comparing the plurality of sensing voltages with a preset first reference voltage respectively, and the corresponding sensing unit generates a first feedback signal when one sensing voltage is lower than the first reference voltage; and the voltage regulation unit increases the driving voltage based on the first feedback signal.
Description
Technical field
The present invention relates to electronic technology field, particularly a kind of drive unit and driving voltage control method.
Background technology
Light-emitting diode (LED, Light Emitting Diode) is because characteristics such as supply power voltage is low, power consumption is little, safe and reliable, environmental protection are widely used in lighting field.For example light-emitting diode is applied in the backlight liquid crystal display module.Light-emitting diode is generally exported constant current driven by constant current source to it, so that the luminosity of light-emitting diode is consistent.
Yet, variations in temperature inhomogeneous, when using during because of manufacturing is different, add conductive materials on the circuit board also because the inhomogeneous equivalent resistance that makes all has difference when making, when often causing driving LED between the different LED string always forward voltage (VF, Forward Voltage) fall difference and make the driving between each LED string have problems.If the LED driving voltage is crossed low some LED string that will cause and can't be lighted, but if too high then have too much voltage loss on the driven MOS pipe of constant current source.
Summary of the invention
Given this, be necessary to provide a kind of drive unit that suitable sufficient driving voltage is provided to the LED string.
Also be necessary to provide a kind of driving voltage control method that suitable sufficient driving voltage is provided to the LED string.
A kind of drive unit is used to drive a plurality of loaded work pieces.This drive unit comprises voltage-regulation unit and a plurality of load, this voltage-regulation unit is used to receive direct voltage and works on power, give a plurality of loads with outputting drive voltage, these a plurality of detecting units are used for detecting respectively total forward voltage of corresponding a plurality of loads to produce corresponding a plurality of detecting voltages, these a plurality of detecting units respectively should a plurality of detecting voltages and a preset first reference voltage compare, its corresponding detecting unit produced first feedback signal when detecting voltage was less than first reference voltage therein, and this voltage-regulation unit makes driving voltage increase based on first feedback signal.
A kind of driving voltage control method, it may further comprise the steps:
A plurality of detecting units are detected total forward voltage of corresponding a plurality of loads respectively to produce corresponding a plurality of detecting voltages;
A plurality of detecting units compare a plurality of detecting voltages and a preset first reference voltage respectively, to judge that whether one of them detecting voltage is less than first reference voltage;
Its corresponding detecting unit produced first feedback signal when detecting voltage was less than first reference voltage therein;
The voltage-regulation unit receives first feedback signal, and makes driving voltage increase based on first feedback signal.
Above-mentioned drive unit and driving voltage control method, by a plurality of detecting units are set, these a plurality of detecting units are used for detecting respectively the voltage forward always of a plurality of loads, to produce a plurality of detecting voltages respectively, its corresponding detecting unit produced first feedback signal when detecting voltage was less than first reference voltage therein, thereby the voltage-regulation unit makes driving voltage increase based on first feedback signal, with the total forward load of voltage maximum of enough drivings, in the present embodiment, this load is the LED string, thereby can export the suitableeest sufficient driving voltage to drive a plurality of LED strings.
Description of drawings
Fig. 1 is the detailed circuit diagram of the drive unit of a better embodiment.
Fig. 2 is the flow chart of the driving voltage control method of a better embodiment.
Embodiment
See also Fig. 1, the drive unit 100 of a better embodiment comprise AC/DC converter unit 10, voltage-regulation unit 20, load Ld1, Ld2 ... Ldn, pull-up resistor R1, R2 ... Rn and detecting unit IC1, IC2 ... ICn.Detecting unit IC1, IC2 ... ICn have respectively sense terminal Dt1, Dt2 ... Dtn and feedback output end F1, F2 ... Fn.In the present embodiment, this load Ld1, Ld2 ... Ldn is that example describes with the LED string with a plurality of LED that are connected in series respectively.
AC/DC converter unit 10 is used for alternating voltage is converted to direct voltage.
Voltage-regulation unit 20 is used to receive from the direct voltage of AC/DC converter unit 10 inputs and works on power, with outputting drive voltage to LED go here and there Ld1, Ld2 ... Ldn.
LED string Ld1, Ld2 ... the anode of Ldn all links to each other with voltage-regulation unit 20, LED string Ld1, Ld2 ... the negative electrode of Ldn respectively with detecting unit IC1, IC2 ... sense terminal Dt1, the Dt2 of ICn ... Dtn is continuous.
Pull-up resistor R1, R2 ... the end of Rn all links to each other with voltage-regulation unit 20, pull-up resistor R1, R2 ... the other end of Rn respectively with detecting unit IC1, IC2 ... feedback output end F1, the F2 of ICn ... Fn links to each other.In other embodiments, pull-up resistor R1, R2 ... Rn can be integrated in respectively detecting unit IC1, IC2 ... ICn inside.
Detecting unit IC1, IC2 ... ICn all links to each other with voltage-regulation unit 20.Detecting unit IC1, IC2 ... ICn be respectively applied for detecting LED string Ld1, Ld2 ... Ldn always forward voltage with produce detecting voltage VD1, VD2 ... VDn, this detecting voltage VD1, VD2 ... VDn be respectively driving voltage and LED go here and there Ld1, Ld2 ... voltage poor forward always of Ldn.Wherein, LED string Ld1, Ld2 ... Ldn always forward voltage be respectively LED string Ld1, Ld2 ... Ldn is the forward voltage sum on its a plurality of LED when driving.
Detecting unit IC1, IC2 ... ICn all is preset with first reference voltage.Detecting unit IC1, IC2 ... ICn also be used for will detecting respectively voltage VD1, VD2 ... the VDn and first reference voltage compare.Therein detecting voltage VD1, a VD2 ... VDn during less than first reference voltage its corresponding detecting unit produce first feedback signal.Voltage-regulation unit 20 also is used to receive first feedback signal, and makes driving voltage increase based on first feedback signal.
Under the situation that driving voltage increases, detecting unit IC1, IC2 ... detecting voltage VD1, the VD2 that ICn produced ... VDn also can increase.Detecting unit IC1, IC2 ... detecting voltage VD1, the VD2 that ICn also is used for respectively magnitude of voltage is increased ... the VDn and first reference voltage compare.Therein detecting voltage VD1, a VD2 ... VDn during greater than first reference voltage its corresponding detecting unit produce second feedback signal.Voltage-regulation unit 20 also is used to receive second feedback signal, and makes driving voltage reduce based on second feedback signal.
Particularly, voltage-regulation unit 20 comprises pwm unit 22, the first metal-oxide-semiconductor M1, inductance L 1, the first diode D1, filter capacitor C1.Pwm unit 22 has supply power voltage end 220, Pulse Electric pressure side 240 and feedback end 250.The supply power voltage end 220 of pwm unit 22 links to each other with AC/DC converter unit 10, and it is used to receive the direct voltage of AC/DC converter unit 10 outputs and works on power, and by the adjustable pulse voltage of Pulse Electric pressure side 240 output duty cycles.The feedback end 250 of pwm unit 22 respectively with detecting unit IC1, IC2 ... feedback output end F1, the F2 of ICn ... Fn links to each other.
One end of inductance L 1 connects AC/DC converter unit 10, and the other end connects the anode of the first diode D1.The grid of the first metal-oxide-semiconductor M1 connects the Pulse Electric pressure side 240 of pwm unit 22, source ground, and drain electrode is connected between the anode of the inductance L 1 and the first diode D1.The negative electrode of the first diode D1 is by filter capacitor C1 ground connection.The negative electrode of the first diode D1 also respectively with LED string Ld1, Ld2 ... the anode of Ldn links to each other.In the present embodiment, first metal-oxide-semiconductor is the N-channel MOS pipe.
Below describe with regard to the physical circuit of detecting unit IC1:
Detecting unit IC1 comprises reference voltage module 32, control module 34, pull down resistor Rd, the second metal-oxide-semiconductor M2, the first operational amplifier U1, the second operational amplifier U2 and the second diode D2.In other embodiments, the second diode D2 can not be integrated in detecting unit IC1 inside, and promptly the second diode D2 is arranged at detecting unit IC1 outside.Reference voltage module 32 is used to provide the inverting input of first reference voltage to the first operational amplifier U1, and this reference voltage module 32 also is used to provide the in-phase input end of second reference voltage to the second operational amplifier U2.The inverting input of the second operational amplifier U2 is by pull down resistor Rd ground connection, and the output of the second operational amplifier U2 links to each other with the grid of the second metal-oxide-semiconductor M2.The source electrode of the second metal-oxide-semiconductor M2 connects inverting input and the pull down resistor Rd of the second operational amplifier U2 respectively, and the drain electrode of the second metal-oxide-semiconductor M2 connects the negative electrode of LED string Ld1.The in-phase input end of the first operational amplifier U1 is connected between the drain electrode of the negative electrode of LED string Ld1 and the second metal-oxide-semiconductor M2, and the output of the first operational amplifier U1 connects the negative electrode of the second diode D2.The anode of the second diode D2 connects the negative electrode of the first diode D1 by pull-up resistor R1.In the present embodiment, second metal-oxide-semiconductor is the N-channel MOS pipe.
The operation principle of drive unit 100 is as follows:
When voltage-regulation unit 20 outputting drive voltage V1 to LED go here and there Ld1, Ld2 ... during Ldn, LED string Ld1 always forward voltage be V2, the detecting voltage VD1=V1-V2 of sense terminal D1.When always forward voltage V2 increase when causing detecting voltage VD1 less than first reference voltage, the first operational amplifier U1 output low level voltage, the feedback end 250 of pwm unit 22 is a low level voltage.Therefore pwm unit 22 can increase by the duty ratio of the pulse voltage of its Pulse Electric pressure side 240 outputs, and the ON time of the first metal-oxide-semiconductor M1 is elongated, stores more energy in the inductance L 1, therefore makes driving voltage V1 increase.
When driving voltage V1 increased, detecting voltage VD1 also can increase, when detecting voltage VD1 greater than first reference voltage, and the first operational amplifier U1 output high level voltage, the feedback end 250 of pwm unit 22 is a high level voltage.Therefore pwm unit 22 can reduce by the duty ratio of the pulse voltage of its Pulse Electric pressure side 240 outputs, and the ON time of the first metal-oxide-semiconductor M1 shortens, and stores less energy in the inductance L 1, therefore makes driving voltage V1 reduce.By the adjusting of the 20 couples of driving voltage V1 in voltage-regulation unit, finally make the detecting voltage VD1 of sense terminal D1 equate with the first reference voltage V ref1.Also be LED string Ld1 always forward voltage V2 be constant voltage, i.e. V2=V1-Vref1, thus realized to LED string Ld1, Ld2 ... the constant voltage of Ldn drives.
Because the second operational amplifier U2 works in empty short status, also promptly the voltage of the inverting input of the second operational amplifier U2 equals the second reference voltage V ref2 simultaneously.Because the second reference voltage V ref2 is a constant voltage, therefore flow through the electric current I of LED string Ld1
1Also be constant electric current, i.e. I
1=Vref2/Rd, thus realized to LED string Ld1, Ld2 ... the constant current driven of Ldn.
See also Fig. 2, the driving voltage control method 200 of a better embodiment may further comprise the steps:
Those skilled in the art will be appreciated that; above execution mode only is to be used for illustrating the present invention; and be not to be used as limitation of the invention; as long as within connotation scope of the present invention, appropriate change and the variation that above embodiment did all dropped within the scope of protection of present invention.
Claims (12)
1. drive unit, be used to drive a plurality of loaded work pieces, it is characterized in that: this drive unit comprises voltage-regulation unit and a plurality of detecting units that are connected with a plurality of loads respectively, this voltage-regulation unit is used to receive direct voltage and works on power, give a plurality of loads with outputting drive voltage, these a plurality of detecting units are used for detecting respectively total forward voltage of corresponding a plurality of loads to produce corresponding a plurality of detecting voltages, these a plurality of detecting units respectively should a plurality of detecting voltages and a preset first reference voltage compare, its corresponding detecting unit produced first feedback signal when detecting voltage was less than first reference voltage therein, and this voltage-regulation unit makes driving voltage increase based on first feedback signal.
2. drive unit as claimed in claim 1 is characterized in that: its corresponding detecting unit produced second feedback signal when detecting voltage was greater than first reference voltage therein, and this voltage-regulation unit also reduces driving voltage based on second feedback signal.
3. drive unit as claimed in claim 2 is characterized in that: this load is a LED string, voltage poor forward always that this LED string comprises that a plurality of LED that are connected in series, these a plurality of detecting voltages are respectively that this driving voltage and a plurality of LED go here and there.
4. drive unit as claimed in claim 3 is characterized in that: this drive unit also comprises a plurality of pull-up resistors that link to each other with a plurality of detecting units respectively, and these a plurality of pull-up resistors all link to each other with the voltage-regulation unit.
5. drive unit as claimed in claim 3 is characterized in that: the anode of these a plurality of LED strings all connects the voltage-regulation unit, and the negative electrode of these a plurality of LED strings links to each other with a plurality of detecting units respectively.
6. drive unit as claimed in claim 4, it is characterized in that: this detecting unit comprises the reference voltage module that is used to provide first reference voltage and second reference voltage, first operational amplifier, second operational amplifier, pull down resistor, second diode, second metal-oxide-semiconductor, the in-phase input end of this second operational amplifier is used to receive second reference voltage, inverting input is by pull down resistor ground connection, the output of this second operational amplifier connects the grid of second metal-oxide-semiconductor, the source electrode of this second metal-oxide-semiconductor connects the inverting input of second operational amplifier, the drain electrode of this second metal-oxide-semiconductor connects the negative electrode of LED string, the in-phase input end of this first operational amplifier is connected between the negative electrode of the drain electrode of second metal-oxide-semiconductor and LED string, inverting input is used to receive first reference voltage, the output of this first operational amplifier connects the negative electrode of second diode, and the anode of this second diode connects pull-up resistor and voltage-regulation unit respectively.
7. drive unit as claimed in claim 6, it is characterized in that: this drive unit also comprises second diode, this detecting unit comprises the reference voltage module that is used to provide first reference voltage and second reference voltage, first operational amplifier, second operational amplifier, pull down resistor, second metal-oxide-semiconductor, the in-phase input end of this second operational amplifier is used to receive second reference voltage, inverting input is by pull down resistor ground connection, the output of this second operational amplifier connects the grid of second metal-oxide-semiconductor, the source electrode of this second metal-oxide-semiconductor connects the inverting input of second operational amplifier, the drain electrode of this second metal-oxide-semiconductor connects the negative electrode of LED string, the in-phase input end of this first operational amplifier is connected between the negative electrode of the drain electrode of second metal-oxide-semiconductor and LED string, inverting input is used to receive first reference voltage, the output of this first operational amplifier connects the negative electrode of second diode, and the anode of this second diode connects pull-up resistor and voltage-regulation unit respectively.
8. drive unit as claimed in claim 6, it is characterized in that: this voltage-regulation unit comprises pwm unit, first metal-oxide-semiconductor, inductance, first diode, filter capacitor, this pwm unit has the supply power voltage end, Pulse Electric pressure side and feedback end, this supply power voltage termination is received direct voltage, this feedback end is connected between the anode of the pull-up resistor and second diode, this Pulse Electric pressure side links to each other with the grid of first metal-oxide-semiconductor, this inductance is connected between the anode of the supply power voltage end and first diode, the negative electrode of this first diode is by filter capacitor ground connection, the negative electrode of this first diode also links to each other with the anode of a plurality of LED strings respectively, the source ground of this first metal-oxide-semiconductor, the drain electrode of this first metal-oxide-semiconductor are connected between the inductance and first diode.
9. drive unit as claimed in claim 8, it is characterized in that: this detecting unit also comprises control module, this control module is used to control the reference voltage module and stops to export first reference voltage and second reference voltage, and this control module also is used to control second metal-oxide-semiconductor and is in cut-off state.
10. driving voltage control method, it may further comprise the steps:
A plurality of detecting units are detected total forward voltage of corresponding a plurality of loads respectively to produce corresponding a plurality of detecting voltages;
A plurality of detecting units compare a plurality of detecting voltages and a preset first reference voltage respectively, to judge that whether one of them detecting voltage is less than first reference voltage;
Its corresponding detecting unit produced first feedback signal when detecting voltage was less than first reference voltage therein;
The voltage-regulation unit receives first feedback signal, and makes driving voltage increase based on first feedback signal.
11. driving voltage control method as claimed in claim 10 is further comprising the steps of:
Its corresponding detecting unit produced second feedback signal when detecting voltage was greater than first reference voltage therein;
The voltage-regulation unit receives second feedback signal, and makes driving voltage reduce based on second feedback signal.
12. driving voltage control method as claimed in claim 10, it is characterized in that: these a plurality of loads are a plurality of LED strings, voltage poor forward always that this LED string comprises that a plurality of LED that are connected in series, these a plurality of detecting voltages are respectively that this driving voltage and a plurality of LED go here and there.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910169672.4A CN101998729B (en) | 2009-08-31 | 2009-08-31 | Driving device and driving voltage regulation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910169672.4A CN101998729B (en) | 2009-08-31 | 2009-08-31 | Driving device and driving voltage regulation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101998729A true CN101998729A (en) | 2011-03-30 |
| CN101998729B CN101998729B (en) | 2014-02-26 |
Family
ID=43787977
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910169672.4A Active CN101998729B (en) | 2009-08-31 | 2009-08-31 | Driving device and driving voltage regulation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101998729B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104955197A (en) * | 2014-03-25 | 2015-09-30 | 深圳市海洋王照明工程有限公司 | Voltage detecting circuit and lamp |
| TWI711337B (en) * | 2019-05-07 | 2020-11-21 | 益力半導體股份有限公司 | Self-adaptive dimming drive system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790127A (en) * | 2004-12-13 | 2006-06-21 | 广达电脑股份有限公司 | LED drive device |
| CN101080119A (en) * | 2006-05-24 | 2007-11-28 | 电力集成公司 | Method and apparatus to power light emitting diode arrays |
| CN201116672Y (en) * | 2007-11-21 | 2008-09-17 | 亚源科技股份有限公司 | Equal-current controllable light-emitting diode array circuit |
-
2009
- 2009-08-31 CN CN200910169672.4A patent/CN101998729B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790127A (en) * | 2004-12-13 | 2006-06-21 | 广达电脑股份有限公司 | LED drive device |
| CN101080119A (en) * | 2006-05-24 | 2007-11-28 | 电力集成公司 | Method and apparatus to power light emitting diode arrays |
| CN201116672Y (en) * | 2007-11-21 | 2008-09-17 | 亚源科技股份有限公司 | Equal-current controllable light-emitting diode array circuit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104955197A (en) * | 2014-03-25 | 2015-09-30 | 深圳市海洋王照明工程有限公司 | Voltage detecting circuit and lamp |
| TWI711337B (en) * | 2019-05-07 | 2020-11-21 | 益力半導體股份有限公司 | Self-adaptive dimming drive system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101998729B (en) | 2014-02-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103648219B (en) | Light-emitting diode (LED) switch constant-current driving circuit | |
| US8558462B2 (en) | Driving circuit for cascade light emitting diodes | |
| CN102469647B (en) | Feedback control circuit and light-emitting diode driving circuit | |
| CN100539782C (en) | Light source driving circuit and driving method thereof | |
| CN103280193A (en) | Backlight driving circuit, liquid crystal display device and backlight driving method | |
| CN103280190A (en) | Backlight driving circuit, liquid crystal display device and backlight driving method | |
| CN103037597A (en) | Multi-channel LED (Light Emitting Diode) constant current control circuit and LED light source control system | |
| US20090230880A1 (en) | Driving circuit and method for light emitting diode | |
| CN104159351B (en) | Feedback control circuit and LED driving circuit | |
| KR101778898B1 (en) | Led backlight driving circuit and liquid crystal display | |
| CN202941027U (en) | Device for driving multiple strings of light emitting diodes | |
| CN2862144Y (en) | Constant-current source apparatus | |
| CN101527988B (en) | Light source driver module and circuit | |
| CN102984860A (en) | Light emitting diode (LED) dimming drive module, backlight module and liquid crystal display device | |
| CN100546420C (en) | Light source driving circuit | |
| US9661705B1 (en) | Power conversion apparatus for decreasing number of pins | |
| CN102917518A (en) | Method for achieving LED (Light-emitted Diode) light bar current multiplication and corresponding drive circuit thereof | |
| US20110089853A1 (en) | Electronic driver apparatus for large area solid-state leds | |
| CN102354483A (en) | LED (Light Emitting Diode) backlight-source boosting driving circuit, LED backlight source and liquid crystal display device | |
| CN201946274U (en) | Constant-temperature constant-current LED (light emitting diode) drive circuit | |
| CN101998729B (en) | Driving device and driving voltage regulation method | |
| CN205546073U (en) | There is not stroboscopic LED drive circuit | |
| CN102917517B (en) | Method for generating different current driving lamp bars by utilizing constant current driving chip and driving circuit thereof | |
| CN103024977A (en) | Light emitting diode driving circuit | |
| CN201563272U (en) | LED dimming drive circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20151204 Address after: 200002 Shanghai City, Pudong New Area source deep road, No. 1122 Patentee after: STATE GRID SHANGHAI MUNICIPAL ELECTRIC POWER Co. Address before: 510640 Guangdong city of Guangzhou province Tianhe District gold Yinglu No. 1 was 1106 room two Patentee before: GUANGDONG HUABO ENTERPRISE MANAGEMENT CONSULTING Co.,Ltd. Effective date of registration: 20151204 Address after: 510640 Guangdong city of Guangzhou province Tianhe District gold Yinglu No. 1 was 1106 room two Patentee after: GUANGDONG HUABO ENTERPRISE MANAGEMENT CONSULTING Co.,Ltd. Address before: China Taiwan Hsinchu Science Park industrial innovation 12, No. 6 Building Patentee before: Fitipower Integrated Technology, Inc. |