CN104768263A - Adaptive LED boost driving circuit - Google Patents
Adaptive LED boost driving circuit Download PDFInfo
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- CN104768263A CN104768263A CN201410002146.XA CN201410002146A CN104768263A CN 104768263 A CN104768263 A CN 104768263A CN 201410002146 A CN201410002146 A CN 201410002146A CN 104768263 A CN104768263 A CN 104768263A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract
The invention discloses an adaptive LED boost driving circuit. The voltage of a second voltage dividing resistor in a voltage feedback circuit is automatically detected. When the detected voltage is smaller than a preset voltage value, the boost driving circuit selects a pulse frequency modulation technology to carry out boost driving; and when the detected voltage is greater than the preset voltage value, the boost driving circuit selects a pulse width modulation technology to carry out boost driving. Moreover, based on dimming signals output by a dimming circuit, the boost driving circuit outputs different voltage signals, the magnitude of current on a main loop is changed, and the brightness of an LED light source is changed. Through automatic boost driving mode selection, the problem that which boost driving mode is selected for driving cannot be determined when the load size is not clear is avoided, the step of measuring the resistance of the light source is omitted, the circuit is convenient to use, and the driving time is saved. Furthermore, adjustment of the brightness of the LED light source is realized, and the scope of application of LED light source is expanded. The adaptive LED boost driving circuit is convenient to use and practical.
Description
Technical field
The present invention relates to lighting technical field, particularly relate to a kind of adaptive LED booster driving circuit.
Background technology
Light-emitting diode (Light-Emitting Diode, LED) is a kind of semiconductor electronic component that can be luminous.The diode be made up of the compound of gallium and arsenic, phosphorus, can give off visible ray when electronics and hole-recombination, thus can be used for making light-emitting diode.As indicator light in circuit and instrument, or form word or numerical monitor.Along with the continuous progress of technology, light-emitting diode has been widely used in display, television set daylighting decoration and illumination.
The power supply circuits of tradition LED are all storage battery power supplies, need booster circuit to drive.Traditional booster driving circuit comprises pulse width modulating technology and pulse frequency modulated technology, when carrying out boosting and driving, drives, drive for large LED load strobe pulse width modulation technology for little LED load strobe pulse frequency modulating technology.
But, for the indefinite situation of load, cannot determine to select which boosting type of drive to drive, need first to determine that load selects drive circuit again, comparatively bother.
Summary of the invention
Based on this, be necessary first to determine that load carries out the problem driven of boosting again for load indefinite needs, provide a kind of needs to determine that load directly can carry out the adaptive LED booster driving circuit driven.
A kind of adaptive LED booster driving circuit, comprising:
Inductor, connects the positive pole of power supply and LED light source, and the negative pole of described LED light source connects earth potential; Described light source, inductor and LED light source form major loop;
Booster driving circuit, comprise power end, output, Schema control end, pressure feedback port and Enable Pin, described power end connects described power supply, and described output connects the common port of described inductor and described LED light source;
Voltage feedback circuit, comprises the first divider resistance and the second divider resistance, described first divider resistance and the rear described LED light source in parallel of the second divider resistance series connection; The pressure feedback port of described booster driving circuit connects the common port of described first divider resistance and the second divider resistance;
Adaptation control circuit, comprises signal input part and signal output part, and described signal input part connects the common port of described first divider resistance and the second divider resistance, and described signal output part connects described Schema control end; When the voltage detected is less than the first voltage preset value, described adaptation control circuit by described signal output part to described Schema control end output low level, described booster driving circuit strobe pulse frequency modulating technology carries out boosting and drives, when the voltage detected is greater than described first voltage preset value, export high level to described Schema control end, described booster driving circuit strobe pulse width modulation technology carries out boosting and drives;
Light adjusting circuit, the input of described light adjusting circuit connects described power supply, and the output of light adjusting circuit connects the Enable Pin of described booster driving circuit, provides dim signal for giving described booster driving circuit.
Wherein in an embodiment, described adaptation control circuit comprises the analog-to-digital conversion module of series connection, single-chip microcomputer and pull down resistor, described analog-to-digital conversion module connects the common port of described first divider resistance and described second divider resistance, described pull down resistor is connected described Schema control end with the common port of described single-chip microcomputer, the other end ground connection of described pull down resistor.
Wherein in an embodiment, described adaptation control circuit also comprises filtration module, and described filtration module connects the input end of described analog-to-digital conversion module.
Wherein in an embodiment, described first voltage preset value is 1.5V.
Wherein in an embodiment, when the voltage of described pressure feedback port is less than the second voltage preset value, described booster driving circuit increases the voltage that described output exports; When the voltage of described pressure feedback port is greater than the second voltage preset value, described booster driving circuit is closed and is exported.
Wherein in an embodiment, described light adjusting circuit is output signal adjustable time-base circuit.
Wherein in an embodiment, described time-base circuit is the adjustable time-base circuit of described output signal that ICM7555 chip and corresponding peripheral circuit are formed;
The discharge end of described ICM7555 chip is connected power end and the threshold value end of described ICM7555 chip respectively by the first adjustable resistance and the second adjustable resistance, the output of described ICM7555 chip connects the Enable Pin of described booster driving circuit;
By regulating described first adjustable resistance and the second adjustable resistance, the output of described ICM7555 chip exports the pulse width modulating signal of different amplitude.
Wherein in an embodiment, described booster driving circuit is TPS61086 chip, 8 pin IN of described TPS61086 chip hold as described power end, as described output after 6 pin SW ends, 7 pin SW hold and connect, 9 pin MODE hold as described Schema control end, 2 pin FB hold as described pressure feedback port, and 3 pin EN hold as described Enable Pin.
Wherein in an embodiment, when the working temperature of described booster driving circuit exceedes preset temperature, described booster driving circuit is closed automatically.
Wherein in an embodiment, described adaptive LED booster driving circuit also comprises light source protection circuit, described light source protection circuit described first divider resistance in parallel.
Above-mentioned adaptive LED booster driving circuit, automatically the voltage of the second divider resistance in voltage feedback circuit is detected by adaptation control circuit, thus the automatic booster driving circuit that controls selects corresponding boosting type of drive to carry out boosting driving, when the voltage detected is less than the first voltage preset value, to Schema control end output low level, booster driving circuit strobe pulse frequency modulating technology carries out boosting and drives, when the voltage detected is greater than the first voltage preset value, high level is exported to Schema control end, booster driving circuit strobe pulse width modulation technology carries out boosting and drives, further, the dim signal exported by light adjusting circuit, booster driving circuit exports different voltage signals, and the size of current on major loop changes, and the brightness of LED light source changes.By automatically selecting type of drive of boosting, avoiding and cannot to determine when load is indefinite to select which boosting type of drive to carry out the problem driven, also saving the step of measurement light source resistance sizes, easy to use and save driving time.Further, achieve the brightness regulation of LED light source, expand the range of application of LED light source, convenient and practical.
Accompanying drawing explanation
Fig. 1 is the adaptive LED booster driving circuit schematic diagram of one embodiment of the invention;
Fig. 2 is the adaptive LED booster driving circuit schematic diagram of another embodiment of the present invention.
Embodiment
A kind of adaptive LED booster driving circuit, by automatically detecting the size of current of the LED light source of place in circuit, and automatically select to carry out the circuit driven that boosts according to size of current, avoid in the indefinite situation of load, which cannot determine to select boosting type of drive to carry out the problem driven, also save the step of measurement light source resistance sizes, easy to use and save driving time.Further, above-mentioned adaptive LED booster driving circuit, uses TPS61-86 chip, realizes overvoltage, under-voltage and overheat protective function.Further, the function of above-mentioned adaptive LED booster driving circuit by using light adjusting circuit to achieve dimming light source and Bright Source Protection.
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
Shown in Fig. 1, it is the adaptive LED booster driving circuit schematic diagram of one embodiment of the invention.With reference to figure 1, a kind of adaptive LED booster driving circuit, comprises inductor 120, booster driving circuit 140, voltage feedback circuit 160, adaptation control circuit 180 and light adjusting circuit 190.Above-mentioned inductor 120 connects the positive pole of power supply 200 and LED light source 300, and power supply 200, inductor 120 and LED light source 300 form major loop.Above-mentioned LED light source 300 is in series for series of LED, and the negative pole of LED light source 300 connects earth potential.Booster driving circuit 140 comprises power end A, output B, pressure feedback port C, Schema control end D and Enable Pin E, and the power end A of booster driving circuit 140 connects power supply 200, and output B connects the common port of inductor 120 and LED light source 300.Voltage feedback circuit 160 comprises the first divider resistance R1 and the second divider resistance R2, parallel connection LED light source 300 after above-mentioned first divider resistance R1 and the second divider resistance R2 connects, the pressure feedback port C of above-mentioned booster driving circuit 140 connects the common port of above-mentioned first divider resistance R1 and the second divider resistance R2.Adaptation control circuit 180 comprises signal input part and signal output part (not shown), the signal input part of adaptation control circuit 180 connects the common port of above-mentioned first divider resistance R1 and the second divider resistance R2, and signal output part connects the Schema control end D of above-mentioned booster driving circuit 140; Adaptation control circuit 180 detects the voltage of the second divider resistance R2, when the voltage detected is less than the first voltage preset value, adaptation control circuit 180 by signal output part to Schema control end D output low level, booster driving circuit 140 strobe pulse frequency modulating technology carries out boosting and drives, when the voltage detected is greater than above-mentioned first voltage preset value, export high level to Schema control end D, booster driving circuit 140 strobe pulse width modulation technology carries out boosting and drives.The input of above-mentioned light adjusting circuit 190 connects power supply 200, the output of light adjusting circuit 190 connects the Enable Pin E of booster driving circuit 140, by the dim signal that light adjusting circuit 190 exports, described booster driving circuit 140 exports corresponding voltage, make the current adjustment on major loop, thus LED light source 300 brightness is adjustable.
By automatically selecting type of drive of boosting, avoiding in the indefinite situation of load, cannot determine to select which boosting type of drive to carry out the problem driven, also saving the step of measurement light source resistance sizes, easy to use and save driving time.By regulating the input voltage of booster driving circuit 140 Enable Pin E, thus regulate the electric current on major loop, the brightness realizing LED light source 300 is adjustable to adapt to different applied environments, convenient and practical, and the range of application of above-mentioned LED light source 300 that increased.
Traditional LED illumination drives and uses switching circuit, this circuit itself low in energy consumption, and drive efficiency is high.The type of switching circuit probably can be divided into pulse width modulation (Pulse Width Modulation, PWM) and pulse frequency modulated (Pulse frequency modulation, PFM).During wherein PWM is mainly used in, heavy-loaded circuit, PFM is mainly used in underload circuit.PWM technology is the wide and narrow change of frequency, and PFM technology is the change of having of frequency and nothing, and PWM technology utilizes square-wave pulse width to control to export, and PFM technology utilizes the presence or absence of pulse to control to export.PWM technology is with the difference of PFM technology: for the PFM technology the same for peripheral circuit and PWM technology, when reaching its peak efficiencies, the efficiency of PFM technology and PWM technology is suitable, but before peak efficiencies, the efficiency far of PFM technology is higher than the efficiency of PWM technology, this is the main advantage of PFM technology, is also that PFM technology is applicable to underload, PWM technology is applicable to heavy duty reason; PWM technology is due to the impact of error amplifier, and loop gain and response speed are restricted, and PFM technology has response speed faster, PWM technology is fixing in whole work period frequency, and PFM technology is not, therefore, PFM technology compare PWM technology major defect be filtering difficulty; PFM technical controlling compares that PWM technical controlling IC price is expensive, and PWM Control Technique implements easily, and PFM control method implements not too easy, so in practical application, common is greatly that PWM controls, and rare PFM controls.
Shown in Fig. 2, it is the adaptive LED booster driving circuit schematic diagram of another embodiment of the present invention.
With reference to figure 2, above-mentioned adaptation control circuit 180 comprises the analog-to-digital conversion module 182 of series connection, single-chip microcomputer 184 and pull down resistor R3.Above-mentioned analog-to-digital conversion module 182 connects the common port of the first divider resistance R1 and the second divider resistance R2, the common port connection mode control end D of single-chip microcomputer 184 and pull down resistor R3, the other end ground connection of pull down resistor R3.For analog-to-digital conversion module 182, its one end connecting the common port of above-mentioned first divider resistance R1 and the second divider resistance R2 is the input end of analog-to-digital conversion module 182, is also the signal input part of above-mentioned adaptation control circuit 180; For adaptation control circuit 180, the one end connecting above-mentioned Schema control end D is the signal output part of above-mentioned adaptation control circuit 180.
Above-mentioned analog-to-digital conversion module 182 detects the current analog signal on above-mentioned voltage feedback circuit 160, and convert above-mentioned current analog signal to voltage digital signal and be transferred to above-mentioned single-chip microcomputer 184, if the voltage swing of above-mentioned voltage digital signal is more than the first voltage preset value, represent that LED light source 300 load is comparatively large, single-chip microcomputer 184 exports high level to Schema control end D; If above-mentioned voltage is less than the first voltage preset value, represent that LED light source 300 load is less, single-chip microcomputer 184 output low level is to Schema control end D.Concrete, above-mentioned first preset value is 1.5V.In other examples, above-mentioned pre-set current value also can be 0.8V-1.5V, according to concrete drive circuit need setting.
The i.e. AD conversion chip of above-mentioned analog-to-digital conversion module 182, carries out AD detection by above-mentioned analog-to-digital conversion module 182.In other embodiments, above-mentioned single-chip microcomputer 184 also can built-in analog-to-digital conversion module 182.
Further, with reference to figure 2, above-mentioned adaptation control circuit 180 also comprises filtration module 186, and filtration module 186 connects the input end of analog-to-digital conversion module 182, the Wen Bo on the major loop that filtering inductor L and LED light source 300 are formed, electromagnetic wave or other fluctuations.Concrete, above-mentioned filtration module 186 is low-pass filter circuit, one of high-pass filtering circuit or bandwidth-limited circuit, or for combining the compound filter circuit of above-mentioned filter circuit.In other examples, above-mentioned filtration module 186 also can be filtering chip.
Concrete, above-mentioned light adjusting circuit 190 be output signal adjustable time-base circuit (not shown), and in the present embodiment, above-mentioned time-base circuit can be the time-base circuit that 555 family chips and corresponding peripheral circuit are formed.Concrete, above-mentioned 555 chips can be ICM7555 chip.1 pin GND of above-mentioned ICM7555 chip holds and connects earth potential; 2 pin TRIG hold as trigger end, after connecting capacitor C6, connect earth potential; 3 pin OUTPUT hold as output, and connect the Enable Pin E of above-mentioned booster driving circuit 140, namely the 3 pin EN of TPS61086 hold; 6 pin TH hold as threshold values end, and 7 pin DIS are discharge end, and 8 pin V+ are power end, and discharge end DIS is connected power end V+ and threshold values end TH respectively by the first adjustable resistance R6 and the second adjustable resistance R7, and power end V+ connects power supply VCC.
By regulating the first adjustable resistance R6 and the second adjustable resistance R7, the output of ICM7555 chip exports the pulse width modulating signal of different amplitude, the Enable Pin E of booster driving circuit 140 receives above-mentioned pulse width modulating signal and carries out amplification and outputs to major loop, cause the electric current of major loop to change thus cause the respective change of LED light source 300 brightness, realizing the light modulation of LED light source 300.
Concrete, the operating voltage of above-mentioned ICM7555 is 2-18V.Wherein, above-mentioned dim signal is pulse width modulating signal.The frequency of dim signal is by formulae discovery below:
wherein R
a, R
bbe respectively the resistance value of the first adjustable resistance R6 and the second adjustable resistance R7, C is the electric capacity of the C6 of capacitor shown in Fig. 2.Wherein, duty ratio computing formula is:
can find out, as long as regulate the resistance of the first adjustable resistance R6 or the second adjustable resistance R7 just can carry out light modulation.
With reference to figure 2, above-mentioned booster driving circuit 140 is specially TPS61086 chip.
1 pin COMP of TPS61086 chip holds as compensating end, by ground connection after series resistance R5 and capacitor C1, can improve load transient response ability.Concrete, above-mentioned R5 resistance is 16k Ω, and the electric capacity of capacitor is 2.7nF.
2 pin FB of TPS61086 chip hold as pressure feedback port (i.e. above-mentioned pressure feedback port C, with reference to figure 1), connect the first divider resistance R1 of series connection and the common port of the second divider resistance R2.
If the maximum occurrences that the voltage on the output voltage of the public end of the first divider resistance R1 and the second divider resistance R2 and FB pin is VS, VS can not more than 18.5V.Concrete, the computing formula of above-mentioned first divider resistance R1, the second divider resistance R2 resistance size is:
wherein V
fB=1.238V is feedback regulation voltage i.e. the second voltage preset value.When voltage on FB pin is less than above-mentioned second voltage preset value, booster driving circuit 140 i.e. TPS61086 chip increases the output voltage of output, realizes under-voltage protection; When the voltage on FB pin is greater than above-mentioned second voltage preset value, booster driving circuit 140 i.e. TPS61086 chip is closed and is exported, and realizes overvoltage protection.Concrete, in another embodiment, when the voltage of FB pin higher than normal value (i.e. 1.238V) 3% time, TPS61086 chip can close output, until recover normal work when the voltage of FB pin gets back to normal value, namely above-mentioned second voltage preset value is 1.238*(1+3%) V.Further, misoperation during in order to prevent under-voltage, when the voltage of power supply VCC is lower than 2.2V, above-mentioned booster driving circuit 140, is TPS61086 chip in the present embodiment, can closes output, further ensures the stability that circuit integrity runs.
Further, with reference to figure 2, above-mentioned adaptive LED booster driving circuit also comprises light source protection circuit 170; above-mentioned light source protection circuit 170 above-mentioned first divider resistance R1 in parallel; for breaking down at circuit, when causing major loop output overvoltage, LED light source 300 is protected.Concrete, above-mentioned light source protection circuit 170 can be voltage-stabiliser tube ZD and the current-limiting resistance R4 of series connection.Wherein, above-mentioned voltage-stabiliser tube ZD can be 15V, and above-mentioned current-limiting resistance R4 is to carry out current limliting when being reversed puncturing at voltage-stabiliser tube ZD.In other examples, above-mentioned light source protection circuit 170 also can direct above-mentioned LED light source 300 in parallel, protects LED light source 300 when major loop output overvoltage.
3 pin EN pins of TPS61086 chip are Enable Pin (the i.e. Enable Pin E of above-mentioned booster driving circuit 140 of TPS61086 chip, with reference to figure 1), connect the output of above-mentioned light adjusting circuit 190, namely 3 pin OUTPUT of ICM7555 chip hold (with reference to figure 2), when ICM7555 chip exports high level, TPS61086 chip is started working, and is amplified by the corresponding voltage signal that ICM7555 chip exports.When regulating the peripheral circuit of above-mentioned ICM7555 chip namely to regulate the first adjustable resistance R6 and the second adjustable resistance R7, the amplitude of the signal magnitude that ICM7555 chip exports can change, the voltage signal size that corresponding TPS61086 chip exports also can produce corresponding change, thus regulates the brightness of LED light source 300.
4 pins of TPS61086 chip, 5 pins and AGND end and PGND end, connect earth potential respectively.6 pins of TPS61086 chip, 7 pins are respectively SW end, as output (the i.e. output B of above-mentioned booster driving circuit 140 of TPS61086 chip after above-mentioned 6 pins, 7 pins connect, with reference to figure 1), the output of above-mentioned TPS61086 chip connects the common port of inductor L and LED light source 300 in major loop.TPS61086 chip exports to above-mentioned major loop, with driving LED light source 300 after being amplified by the voltage signal that Enable Pin EN inputs.
Concrete, the inductance size of above-mentioned inductor L is 3.3uH-5uH, and computing formula is as follows: L=(V
iN/ Vs)
2* ((V
s-V
iN)/(I
oUT* f
s)) * (η/0.35).Wherein V
iNfor the input voltage of inductor L, I
oUTfor the output current of inductor L, η is circuit efficiency, and in the present embodiment, foregoing circuit efficiency specifically can be 90%; f
sfor the operating frequency of the switching tube of TPS61086 chip, f in the present embodiment
sfor fixed frequency 1.2MHz.
8 pin IN of TPS61086 chip hold power end (the i.e. power end A of above-mentioned booster driving circuit 140 for TPS61086 chip, with reference to figure 1), connect power supply VCC(and power supply 200, with reference to figure 1), power supply VCC is storage battery in the present embodiment, and general output voltage is 2.3V-6V.
Further, above-mentioned adaptive LED booster driving circuit also comprises filter circuit 150, connects the power end IN of TPS61086 chip, for carrying out High frequency filter to the power supply signal of input supply terminal IN.Concrete, above-mentioned filter circuit 150 is ceramic disc capacitor C4.Further, above-mentioned adaptive LED booster driving circuit also comprises electric source filter circuit 130, is connected to power supply VCC output, carries out low frequency filtering for the power supply signal exported power supply VCC.Concrete, above-mentioned electric source filter circuit 130 is electrochemical capacitor C4.
9 pin MODE of TPS61086 chip hold Schema control end (the i.e. Schema control end D of above-mentioned booster driving circuit 140 for TPS61086 chip, with reference to figure 1), during above-mentioned Schema control end MODE input high level, TPS61086 chip uses PWM technology to carry out boosting and drives, during above-mentioned Schema control end pin input low level, TPS61086 chip uses PFM technology to carry out boosting and drives.Shown in Fig. 2, above-mentioned Schema control end MODE connects the common port of above-mentioned single-chip microcomputer 184 and pull down resistor R3, and when single-chip microcomputer 184 exports high level, TPS61086 chip uses PWM technology to carry out boosting and drives; During single-chip microcomputer 184 output low level, TPS61086 chip uses PFM technology to carry out boosting and drives.
10 pin SS pins of TPS61086 chip are soft start pin, and after capacitor C2 ground connection, TPS61086 chip will carry out soft start, can prevent the interference of surge current.The electric capacity of usual above-mentioned capacitor C2 is 100nF, when above-mentioned adaptive LED booster driving circuit energising, when Enable Pin EN end detects high level, capacitor C2 is charged to 0.3V at once, then the current charges with 10uA is continued, until output voltage reaches 90% of rated value.When circuit closes input, capacitor C2 discharges over the ground.The capacitance of capacitor C2 is larger, and Anti-surging ability is stronger.
Further, when the working temperature of above-mentioned booster driving circuit 140 exceedes preset temperature, booster driving circuit 140 is closed automatically.In the embodiment depicted in figure 2, when the working temperature of TPS61086 chip exceedes preset temperature, the switching tube in TPS61086 chip disconnects automatically, and TPS61086 chip quits work.Concrete, above-mentioned preset temperature is 150 DEG C.The working temperature that above-mentioned TPS61086 chip allows is within 136 DEG C, and when working temperature reaches 150 DEG C, TPS61086 chip quits work automatically, until when the temperature of circuit is lower than 136 DEG C, TPS61086 chip recovers normal work.
Further, with reference to figure 2, above-mentioned adaptive LED booster driving circuit also comprises filtering capacitor C5, C5 parallel connection LED light source 300.
The major loop that above-mentioned inductor L and LED light source 300 are formed also is provided with unidirectional conducting switch (figure does not mark), unidirectional conducting switch connects the positive pole of inductor L and LED light source 300 respectively, can not reflux for preventing the electric charge of above-mentioned capacitor C5 to the output B of above-mentioned inductor L and booster driving circuit 140.Concrete, above-mentioned unidirectional conducting switch is one-way conduction diode D.
When the IN end energising of TPS61086 chip, Enable Pin EN connects high level, switching tube in TPS61086 chip is opened, the electric current that power supply VCC inputs is through inductor L, SW end, the PGND end of TPS61086 chip form loop, during this period, inductor L stored energy, LED light source 300 is powered by capacitor C5 entirely.When the switching tube of TPS61086 chip is closed, due to the effect of back-emf, the energy that inductor L stores is powered to capacitor C5 and LED light source 300 through one-way conduction diode D.Due to the existence of one-way conduction diode D, the electric charge of capacitor C5 can not reflux to the SW end of inductor L or TPS61086 chip.
Below in conjunction with the principle of circuit embodiment illustrated in fig. 2, the principle of adaptive LED booster driving circuit of the present invention is described in more detail.
Power supply VCC exports the voltage of 2.3V-6V, the major loop that a road is formed through inductor L, one-way conduction diode D and LED light source 300, the wherein minus earth of LED light source 300.
Low-pass filtering, electric capacity C4 are input to TPS61086 chip 8 pin power end IN after carrying out high-pass filtering are carried out, for TPS61086 chip provides operating voltage through electric capacity C3 in one tunnel.During ICM7555 chip output low level, the switching tube in TPS61086 chip is opened, and TPS61086 chip does not work; When ICM7555 chip exports high level, 3 pin enabled end EN of TPS61086 chip access high level, and the switching tube in TPS61086 chip closes, TPS61086 chip unlatching work.
During the switching tube of TPS61086 chip is opened, the electric current that power supply VCC exports is held through the SW of inductor L, TPS61086 chip, PGND end forms loop, and during this period, inductor L storage power, LED light source 300 is powered by electric capacity C5 entirely.When the switching tube of TPS61086 chip is closed, due to the effect of back-emf, the energy that inductor L stores is powered to electric capacity C5 and LED light source 300 through one-way conduction diode D.Due to the existence of one-way conduction diode D, the electric charge of electric capacity C5 can not reflux to the SW end of inductor L or TPS61086 chip.
Voltage feedback circuit 160, the first divider resistance R1 namely connected and the second divider resistance R2, the pressure feedback port FB of parallel connection LED light source 300, TPS61086 chip hold the common port connecting above-mentioned first divider resistance R1 and the second divider resistance R2.When the voltage of FB end is greater than the second voltage preset value, TPS61086 chip quits work, and achieves overvoltage protection; When the voltage of FB end is less than the second voltage preset value, TPS61086 chip increases the voltage that output exports, and achieves under-voltage protection.Concrete, above-mentioned second voltage preset value and feedback regulation voltage are 1.238V.
Adaptation control circuit 180 detects the current analog signal on voltage feedback circuit 160, after filtration module 186 filtering, analog-to-digital conversion module 182 converts above-mentioned current analog signal to voltage digital signal and is transferred to above-mentioned single-chip microcomputer 184, if the voltage swing of above-mentioned voltage digital signal is more than the first voltage preset value, represent that LED light source 300 load is comparatively large, single-chip microcomputer 184 exports high level to Schema control end MODE; If above-mentioned voltage is less than the first voltage preset value, represent that LED light source 300 load is less, single-chip microcomputer 184 output low level is to Schema control end MODE.Concrete, above-mentioned first voltage preset value is 1.5V.
When the Schema control end MODE of TPS61086 chip receives high level, TPS61086 chip uses PWM technology to carry out boosting and drives, and when Schema control end MODE receives low level, TPS61086 chip uses PFM technology to carry out boosting and drives.
When regulating the size of the peripheral circuit first adjustable resistance R6 of ICM7555 chip and the second adjustable resistance R7, ICM7555 chip exports the PWM square-wave signal of respective magnitudes, thus TPS61086 chip boosts to the voltage signal received, export corresponding voltage signal to major loop, thus regulate the brightness of LED light source 300.
Ground connection after 1 pin COMP end series resistance R5 and capacitor C1 of TPS61086 chip, can improve load transient response ability.
Above-mentioned first divider resistance R1 two ends parallel connection LED light source 300 protective circuit 170; comprise voltage-stabiliser tube ZD and the current-limiting resistance R4 of series connection; for breaking down at circuit; when causing major loop output overvoltage; protect LED light source 300, above-mentioned current-limiting resistance R4 is to carry out current limliting when being reversed puncturing at voltage-stabiliser tube ZD.
4 pins of TPS61086 chip, 5 pins and AGND end and PGND end, connect earth potential respectively.10 pin SS pins of TPS61086 chip are soft start pin, and after electric capacity C2 ground connection, TPS61086 chip will carry out soft start, can prevent the interference of surge current.
Further, when the working temperature of above-mentioned TPS61086 chip is higher than 150 DEG C, TPS61086 chip quits work automatically, until when the temperature of circuit is lower than 136 DEG C, TPS61086 chip recovers normal work.
To sum up, above-mentioned adaptive LED booster driving circuit is by automatically detecting the voltage swing of the upper divider resistance of dividing potential drop drive circuit thus automatically selecting corresponding boosting type of drive to drive, simple and convenient; And overheated, overvoltage, under-voltage protection can be realized, make circuit more safe and reliable.
The above embodiment only have expressed several execution mode of the present invention, and it describes comparatively concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection range of patent of the present invention should be as the criterion with claims.
Claims (10)
1. an adaptive LED booster driving circuit, is characterized in that, comprising:
Inductor, connects the positive pole of power supply and LED light source, and the negative pole of described LED light source connects earth potential; Described light source, inductor and LED light source form major loop;
Booster driving circuit, comprise power end, output, Schema control end, pressure feedback port and Enable Pin, described power end connects described power supply, and described output connects the common port of described inductor and described LED light source;
Voltage feedback circuit, comprises the first divider resistance and the second divider resistance, described first divider resistance and the rear described LED light source in parallel of the second divider resistance series connection; The pressure feedback port of described booster driving circuit connects the common port of described first divider resistance and the second divider resistance;
Adaptation control circuit, comprises signal input part and signal output part, and described signal input part connects the common port of described first divider resistance and the second divider resistance, and described signal output part connects described Schema control end; When the voltage detected is less than the first voltage preset value, described adaptation control circuit by described signal output part to described Schema control end output low level, described booster driving circuit strobe pulse frequency modulating technology carries out boosting and drives, when the voltage detected is greater than described first voltage preset value, export high level to described Schema control end, described booster driving circuit strobe pulse width modulation technology carries out boosting and drives;
Light adjusting circuit, the input of described light adjusting circuit connects described power supply, and the output of light adjusting circuit connects the Enable Pin of described booster driving circuit, provides dim signal for giving described booster driving circuit.
2. adaptive LED booster driving circuit according to claim 1, it is characterized in that, described adaptation control circuit comprises the analog-to-digital conversion module of series connection, single-chip microcomputer and pull down resistor, described analog-to-digital conversion module connects the common port of described first divider resistance and described second divider resistance, described pull down resistor is connected described Schema control end with the common port of described single-chip microcomputer, the other end ground connection of described pull down resistor.
3. adaptive LED booster driving circuit according to claim 2, is characterized in that, described adaptation control circuit also comprises filtration module, and described filtration module connects the input end of described analog-to-digital conversion module.
4. adaptive LED booster driving circuit according to claim 1, is characterized in that, described first voltage preset value is 1.5V.
5. adaptive LED booster driving circuit according to claim 1, is characterized in that, when the voltage of described pressure feedback port is less than the second voltage preset value, described booster driving circuit increases the voltage that described output exports; When the voltage of described pressure feedback port is greater than the second voltage preset value, described booster driving circuit is closed and is exported.
6. adaptive LED booster driving circuit according to claim 1, is characterized in that, described light adjusting circuit is output signal adjustable time-base circuit.
7. adaptive LED booster driving circuit according to claim 6, is characterized in that, described time-base circuit is the adjustable time-base circuit of described output signal that ICM7555 chip and corresponding peripheral circuit are formed;
The discharge end of described ICM7555 chip is connected power end and the threshold value end of described ICM7555 chip respectively by the first adjustable resistance and the second adjustable resistance, the output of described ICM7555 chip connects the Enable Pin of described booster driving circuit;
By regulating described first adjustable resistance and the second adjustable resistance, the output of described ICM7555 chip exports the pulse width modulating signal of different amplitude.
8. adaptive LED booster driving circuit according to claim 1, it is characterized in that, described booster driving circuit is TPS61086 chip, 8 pin IN of described TPS61086 chip hold as described power end, as described output after 6 pin SW ends, 7 pin SW hold and connect, 9 pin MODE hold as described Schema control end, and 2 pin FB hold as described pressure feedback port, and 3 pin EN hold as described Enable Pin.
9. adaptive LED booster driving circuit according to claim 7, is characterized in that, when the working temperature of described booster driving circuit exceedes preset temperature, described booster driving circuit is closed automatically.
10. adaptive LED booster driving circuit according to claim 1, is characterized in that, described adaptive LED booster driving circuit also comprises light source protection circuit, described light source protection circuit described first divider resistance in parallel.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108122530A (en) * | 2016-11-28 | 2018-06-05 | 昆山国显光电有限公司 | The call method and display screen of power supply chip and its PWM, PFM |
| CN109863702A (en) * | 2016-10-21 | 2019-06-07 | 昕诺飞控股有限公司 | Current modulating circuit, driving circuit and the method using current-modulation driving lighting load |
| CN110445374A (en) * | 2018-05-03 | 2019-11-12 | 广达电脑股份有限公司 | Voltage band logical enable circuit |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080136354A1 (en) * | 2006-12-12 | 2008-06-12 | Industrial Technology Research Institute | Preheat control device for modulating voltage of gas-discharge lamp |
| CN101430863A (en) * | 2008-12-02 | 2009-05-13 | 晋城市环球利特光电技术有限公司 | Led back light source driving circuit |
| CN101466187A (en) * | 2009-01-05 | 2009-06-24 | 西安理工大学 | LED drive circuit for PFM/PWM bimodal switch light modulation |
| CN101771404A (en) * | 2010-01-08 | 2010-07-07 | 北京巨数数字技术开发有限公司 | LED control chip |
| CN102708804A (en) * | 2011-10-21 | 2012-10-03 | 京东方科技集团股份有限公司 | Backlight dimming method and backlight driving circuit |
| CN203193947U (en) * | 2013-02-01 | 2013-09-11 | 杨仲辉 | Led lamp control system |
-
2014
- 2014-01-02 CN CN201410002146.XA patent/CN104768263B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080136354A1 (en) * | 2006-12-12 | 2008-06-12 | Industrial Technology Research Institute | Preheat control device for modulating voltage of gas-discharge lamp |
| CN101430863A (en) * | 2008-12-02 | 2009-05-13 | 晋城市环球利特光电技术有限公司 | Led back light source driving circuit |
| CN101466187A (en) * | 2009-01-05 | 2009-06-24 | 西安理工大学 | LED drive circuit for PFM/PWM bimodal switch light modulation |
| CN101771404A (en) * | 2010-01-08 | 2010-07-07 | 北京巨数数字技术开发有限公司 | LED control chip |
| CN102708804A (en) * | 2011-10-21 | 2012-10-03 | 京东方科技集团股份有限公司 | Backlight dimming method and backlight driving circuit |
| CN203193947U (en) * | 2013-02-01 | 2013-09-11 | 杨仲辉 | Led lamp control system |
Non-Patent Citations (2)
| Title |
|---|
| 佚名: "TPS61086EVM-526", 《德州仪器网》 * |
| 刘胜利: "新型绿色照明LED电源驱动器(三) 高压、350mA、高亮度LED驱动器MAX16836:内含PWM调光、5V调节器;适用于通用照明、汽车灯光、指示报警", 《电源世界》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109863702A (en) * | 2016-10-21 | 2019-06-07 | 昕诺飞控股有限公司 | Current modulating circuit, driving circuit and the method using current-modulation driving lighting load |
| CN108122530A (en) * | 2016-11-28 | 2018-06-05 | 昆山国显光电有限公司 | The call method and display screen of power supply chip and its PWM, PFM |
| CN110445374A (en) * | 2018-05-03 | 2019-11-12 | 广达电脑股份有限公司 | Voltage band logical enable circuit |
| CN110445374B (en) * | 2018-05-03 | 2020-08-07 | 广达电脑股份有限公司 | Voltage band-pass enabling circuit |
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|---|---|
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