CN204948399U - Zero-frequency dodges LED control device - Google Patents

Abstract

The utility model belongs to lighting field, and provide a kind of zero-frequency to dodge LED control device, described device comprises: 220V power supply constant voltage drive circuit, LED control circuit, constant current driver circuit for LED and LED; Wherein, does 220V power supply constant voltage drive circuit comprise: 36V? AC-DC change-over circuit; 36V? the input of AC-DC change-over circuit connects 220V voltage source, and output connects LED control circuit, and LED control circuit is connected with constant current driver circuit for LED, and constant current driver circuit for LED is electrically connected with LED.The utility model has the advantage that zero-frequency dodges.

Description

Zero-frequency dodges LED control device

Technical field

The utility model belongs to lighting field, particularly relates to a kind of zero-frequency and dodges LED control device.

Background technology

Lighting field, about stroboscopic, the most simply defines the continuous fluctuation just referring to light in switch periods.In the U.S., electric current is that the alternating current being 60Hz by frequency transmits, and the supply power voltage of light fixture fluctuates back and forth between crest to trough with the form of sine wave in switch periods.Therefore, 2 times may be produced to the stroboscopic of frequency of supply, namely 120Hz.If do not have suitable electronic circuit, such as ballast, driving or power supply, light source will produce stroboscopic.

New York Troy LRC(LightingResearchCenter) Director of Studies NadarajahNarendran say: " mankind can discover the light stroboscopic lower than 50Hz, certainly also have some just can notice to 100Hz ".The low stroboscopic of about 3 to 70Hz may cause the epileptic attack of high quick crowd, moderate stroboscopic between about 100 to 500Hz may cause the indirect consciousness (annotation of translation: caused by the persistence of vision) of stroboscopic effect, in this case, dynamic object may show as a series of static image.This effect is perhaps the effect reached desired by dance hall, but is but dangerous for industrial site, such as, stroboscopic can make the gear of movement or blade seem very slow, even static, equally, it also brings a series of adverse influence to health, tired as headache, kopiopia and body and mind.

Traditional light source, such as popular incandescent lamp also has stroboscopic.People do not realize it is because the thermal inertia of incandescent lamp masks stroboscopic problem, cut off the electricity supply, until during energising next time, filament all also leaving waste heat can be luminous.This feature is also the inefficient reason of incandescent lamp, and the electric energy conversion of about 90% is that thermal loss has fallen.LED also has stroboscopic as a kind of new light source.Causing one of stroboscopic Producing reason to be LED lamp is Alternating Current Power Supply, uses the light source of alternating current to have stroboscopic; Two is that electric current shakiness causes stroboscopic equally, although the stroboscopic problem that a lot of LED generally adopts independent constant current (direct current) to regulate driving power circuit to solve alternating current to be brought; But this method, alternating current can produce voltage and current output ripple to galvanic transfer process.This ripple exists with 2 times of frequencies to supply power voltage, still can cause stroboscopic.

Light modulation is the another one inducement causing stroboscopic.Present LED generally adopts pulse width modulation (PWM) signal to realize light modulation.As long as higher than the frequency of 100 hertz.The naked eyes of people just cannot see flicker, but taking general camera just can capture light has in flicker, so one of solution is that frequency is improved.Time 30,000 ~ 50,000, most of camera is also clapped really less than LED in flicker, but high stroboscopic is not equal to without dodging.Still can be arrived by candid photograph below professional test instrument.So existing most of LED illumination light source all has stroboscopic.

Summary of the invention

The object of the utility model embodiment is to provide a kind of zero-frequency to dodge LED control device, is intended to solve the problem that existing technical scheme all has stroboscopic.

On the one hand, provide a kind of zero-frequency to dodge LED control device, described device comprises: 220V power supply constant voltage drive circuit, LED control circuit, constant current driver circuit for LED and LED;

Wherein, 220V power supply constant voltage drive circuit comprises: 36VAC-DC change-over circuit; The input of 36VAC-DC change-over circuit connects 220V voltage source, and output connects LED control circuit, and LED control circuit is connected with constant current driver circuit for LED, and constant current driver circuit for LED is electrically connected with LED.

Optionally, described LED control circuit and constant current driver circuit for LED specifically comprise:

Electric capacity, resistance, triode, diode and chip; Wherein,

One end of resistance R1 is connected with PWM1 signal input part, the base stage of the other end connecting triode Q1 of resistance R1, one end of the emitter contact resistance R2 of triode Q1, the other end of resistance R2 connects 36VAC-DC change-over circuit output, electric capacity C1 and electric capacity C2 is connected in parallel, a common point ground connection of the electric capacity C1 be connected in parallel and electric capacity C2, another common point connects 36VAC-DC change-over circuit output; One end of the collector electrode contact resistance R4 of Q1, the other end base stage of connecting triode Q2 and one end of resistance R5 respectively of resistance R4, the transmitter of the other end connecting triode Q2 of resistance R5, the collector electrode of triode Q2 connects VINA+ (i.e. the anode of LED); The plus earth of diode D1, one end of the negative electrode contact resistance R18 of diode D1, the other end of resistance R18 connects 24V voltage source, electric capacity C3 and electric capacity C4 is connected in parallel, a common point ground connection of the electric capacity C3 be connected in parallel and electric capacity C4, another common point connects 24V power supply, the grounded emitter of triode Q2;

One end of resistance R6 connects the collector electrode of Q2, one end of the other end contact resistance R7 of resistance R6, the other end of resistance R7 connects No. 3 pins of chip, No. 4 pin ground connection of chip, No. 2 pins are connected with one end of resistance R8, the other end of resistance R8 connects the negative electrode of VOUTA(and LED), chip No. 1 pin connects VOUTA, one end of chip No. 8 pin contact resistance R9, the other end of resistance R9 connects 24V power supply, electric capacity C8 is connected 24V power supply with one end of electric capacity C9, other end ground connection, one end of electric capacity C7 connects chip No. 8 pins, the other end ground connection of electric capacity C7,

The other end of one end contact resistance R6 of electric capacity C5, the other end ground connection of electric capacity C5, the other end of one end contact resistance R7 of electric capacity C6, the other end ground connection of electric capacity C6.

In the utility model embodiment, the technical scheme that the utility model provides provides a kind of brand-new device, and it adopts DC power supply, has directly stopped the existence of stroboscopic, and it has the advantage that zero-frequency dodges.

Accompanying drawing explanation

The circuit block diagram of the zero-frequency sudden strain of a muscle LED control device that Fig. 1 provides for utility model;

The circuit theory diagrams of the LED control circuit that Fig. 2 provides for the utility model and constant current driver circuit for LED.

Embodiment

In order to make the purpose of this utility model, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the utility model, and be not used in restriction the utility model.

The utility model embodiment provides a kind of zero-frequency to dodge LED control device, and this device as shown in Figure 1, comprising: 220V power supply constant voltage drive circuit 1, LED control circuit 2, constant current driver circuit for LED 3 and LED;

Wherein, 220V power supply constant voltage drive circuit comprises: 36VAC-DC change-over circuit; The input of 36VAC-DC change-over circuit connects 220V voltage source, and output connects LED control circuit 2, and LED control circuit 2 is connected with constant current driver circuit for LED 3, and constant current driver circuit for LED 3 is electrically connected with LED.

The technical scheme that the utility model provides converts alternating current to direct current and powers to LED, solves stroboscopic because alternating current causes the problem of stroboscopic.

It should be noted that, above-mentioned 36VAC-DC change-over circuit is existing change-over circuit, is not limited to the concrete structure of this change-over circuit here.

Optionally, above-mentioned LED control circuit 2, constant current driver circuit for LED 3 specifically comprise:

Electric capacity, resistance, triode, diode and chip (model C 1563); Wherein,

One end of resistance R1 is connected with PWM1 signal input part, the base stage of the other end connecting triode Q1 of resistance R1, one end of the emitter contact resistance R2 of triode Q1, the other end of resistance R2 connects 36VAC-DC change-over circuit output, electric capacity C1 and electric capacity C2 is connected in parallel, a common point ground connection of the electric capacity C1 be connected in parallel and electric capacity C2, another common point connects 36VAC-DC change-over circuit output; One end of the collector electrode contact resistance R4 of Q1, the other end base stage of connecting triode Q2 and one end of resistance R5 respectively of resistance R4, the transmitter of the other end connecting triode Q2 of resistance R5, the collector electrode of triode Q2 connects VINA+; The plus earth of diode D1, one end of the negative electrode contact resistance R18 of diode D1, the other end of resistance R18 connects 24V voltage source, electric capacity C3 and electric capacity C4 is connected in parallel, a common point ground connection of the electric capacity C3 be connected in parallel and electric capacity C4, another common point connects 24V power supply, the grounded emitter of triode Q2;

One end of resistance R6 connects the collector electrode of Q2, one end of the other end contact resistance R7 of resistance R6, the other end of resistance R7 connects No. 3 pins of chip, No. 4 pin ground connection of chip, No. 2 pins are connected with one end of resistance R8, the other end of resistance R8 connects VOUTA, chip No. 1 pin connects VOUTA, one end of chip No. 8 pin contact resistance R9, the other end of resistance R9 connects 24V power supply, and electric capacity C8 is connected 24V power supply with one end of electric capacity C9, other end ground connection, one end of electric capacity C7 connects chip No. 8 pins, the other end ground connection of electric capacity C7;

The other end of one end contact resistance R6 of electric capacity C5, the other end ground connection of electric capacity C5, the other end of one end contact resistance R7 of electric capacity C6, the other end ground connection of electric capacity C6.

220V constant voltage drive circuit is exported by the constant voltage DC that 220V alternating current is converted to 36V1.3A by AC-DC.Supply LED control circuit and constant current driver circuit for LED.LED control circuit mainly controls LED by single-chip microcomputer output pwm signal.Pulse width modulation (PWM) is that one carries out digitally coded method to analog signal level.By the use of high-resolution counter, modulated being used for of the duty ratio of square wave is encoded to the level of a physical simulation signal.Pwm signal remains numeral, because in given any moment, expires the direct current supply of amplitude or has completely (ON), or completely without (OFF).Voltage or current source are added to fictitious load with the repetition pulse sequence of one logical (ON) or disconnected (OFF) to get on.Namely be namely direct current supply when being added in load time logical, be that power supply is when being disconnected time disconnected.As long as bandwidth is enough, any analogue value can use PWM to encode.Many microcontroller all include PWM controller.Such as, the PIC16C67 of Microchip company includes two PWM controller, and each can select turn-on time and cycle.Duty ratio is turn-on time and the ratio in cycle; Modulating frequency is the inverse in cycle.Therefore, the percentage of LED brightness is equal to the duty ratio of pwm signal.

Constant current driver circuit for LED mainly completes digital signal (pwm signal) by LED constant current drive IC and is converted to analogsimulation signal and controls LED and regulate brightness and directly use digital signal to carry out adjusting brightness of LED lamps.Namely constant current driver circuit for LED can realize the method that two kinds control LED brightness: one is that digital signal revolving die analog signal controls; Two is Direct Digital signal controlling.Freely can switch two kinds of modes.Concrete methods of realizing Digital Signals and analog signal control mode combined is as follows:

When hope controls LED luminance when 16% to 100% is interval, the brightness value of input is converted into pwm signal and exports by LED control circuit, receives PWM1 pin as shown in Figure 2.PWM1 pin input pwm signal, carries out oppositely through triode Q2, more oppositely amplifies through Q1, be consistent to reach phase difference and amplify pwm signal.By the integrating circuit be made up of R29, C30, R30, C29, the pwm signal of amplification is converted to DC simulation voltage signal, draws analog voltage signal by VOUTA pin and control LED luminance.VOUTA pin is connected to the negative electrode of LED lamp bead.Adjusting brightness of LED lamps is realized by changing LED cathode voltage size.

When hope control LED luminance below 15% time, corresponding voltage strength is corresponding less than normal, there will be wild effect time too small for LED magnitude of voltage, instant bright time go out.Now special digital signal (pwm signal) directly controls LED brightness.The brightness value of input is converted into pwm signal and exports by LED control circuit, receives PWM1 pin.PWM1 pin input pwm signal, carries out oppositely through triode Q2, more oppositely amplifies through Q1, be consistent to reach phase difference and amplify pwm signal.VINA pin still output pwm signal, VINA pin connects the negative electrode of LED, controls LED brightness by the duty ratio of pwm signal.

The foregoing is only preferred embodiment of the present utility model; not in order to limit the utility model; all do within spirit of the present utility model and principle any amendment, equivalent to replace and improvement etc., all should be included within protection range of the present utility model.

Claims (2)

1. zero-frequency dodges a LED control device, and it is characterized in that, described device comprises: 220V power supply constant voltage drive circuit, LED control circuit, constant current driver circuit for LED and LED;

Wherein, 220V power supply constant voltage drive circuit comprises: 36VAC-DC change-over circuit; The input of 36VAC-DC change-over circuit connects 220V voltage source, and output connects LED control circuit, and LED control circuit is connected with constant current driver circuit for LED, and constant current driver circuit for LED is electrically connected with LED.

2. device according to claim 1, is characterized in that, described LED control circuit and constant current driver circuit for LED specifically comprise:

Electric capacity, resistance, triode, diode and chip; Wherein,

One end of resistance R1 is connected with PWM1 signal input part, the base stage of the other end connecting triode Q1 of resistance R1, one end of the emitter contact resistance R2 of triode Q1, the other end of resistance R2 connects 36VAC-DC change-over circuit output, electric capacity C1 and electric capacity C2 is connected in parallel, a common point ground connection of the electric capacity C1 be connected in parallel and electric capacity C2, another common point connects 36VAC-DC change-over circuit output; One end of the collector electrode contact resistance R4 of Q1, the other end base stage of connecting triode Q2 and one end of resistance R5 respectively of resistance R4, the transmitter of the other end connecting triode Q2 of resistance R5, the collector electrode of triode Q2 connects VINA+; The plus earth of diode D1, one end of the negative electrode contact resistance R18 of diode D1, the other end of resistance R18 connects 24V voltage source, electric capacity C3 and electric capacity C4 is connected in parallel, a common point ground connection of the electric capacity C3 be connected in parallel and electric capacity C4, another common point connects 24V power supply, the grounded emitter of triode Q2;

One end of resistance R6 connects the collector electrode of Q2, one end of the other end contact resistance R7 of resistance R6, the other end of resistance R7 connects No. 3 pins of chip, No. 4 pin ground connection of chip, No. 2 pins are connected with one end of resistance R8, the other end of resistance R8 connects VOUTA, chip No. 1 pin connects VOUTA, one end of chip No. 8 pin contact resistance R9, the other end of resistance R9 connects 24V power supply, and electric capacity C8 is connected 24V power supply with one end of electric capacity C9, other end ground connection, one end of electric capacity C7 connects chip No. 8 pins, the other end ground connection of electric capacity C7;

The other end of one end contact resistance R6 of electric capacity C5, the other end ground connection of electric capacity C5, the other end of one end contact resistance R7 of electric capacity C6, the other end ground connection of electric capacity C6.