Means of mainstream LED drive and LED drive power source choose skill

  • Time:
  • Click:175
  • source:TRIANA CNC Machining
LED is characteristic and sensitive semiconductor device, have negative temperature character again, need to undertake stabilizing working status and protection to its in using a process consequently, generated the idea of drive thereby. LED parts of an apparatus is approximately slashing to the requirement of drive power source, the incandescent lamp with LED common unlike, can receive the communication town report of 220V one after another continuously. LED is the low voltage drive that 3 bend over control, must want to design complex commutation circuit, the LED lamp of different utility, want to deploy different power source adapter. The demand with life of precision of the efficiency changeover of client of the abroad on the international market to LED drive power source, effective power, constant current, power source, compatible electromagnetism is very high, design a good power supply to must consider these factor integratedly, it is important like the person's heart that because power source is in,the action in whole lamps and lanterns is just like. Because get the limitation of LED power level, need normally at the same time drive many LED in order to satisfy brightness requirement, accordingly, the drive circuit with special need will illume LED. At present the means of drive of a few kinds of LED of the mainstream has a few kinds as follows: Block allows step-down to use capacitance to restrict input electric current in the impedance below communication, obtain dc n to give LED power supply thereby. Structure of means of this kind of drive is simple, cost is low, but input blame keeps apart plan, have safe hidden trouble. And changeover efficiency is very low, cannot accomplish constant current control. Segregation stimulates circuit to use instead stimulate circuit instead, dc n arises in deputy edge through transformer, repass smooth Ou answers the ripple feedback of this n former edge, thereby self-excitation is stable. This kind of circuit is accorded with bring compasses cognizance demand, and precision of output constant current is better, changeover efficiency is taller. But because need smooth Ou and deputy edge constant current,dominate circuit, cause a system complex, volume is large, cost is high. Already replaced for former edge plan gradually at present. Plan of former limit of former edge program communicates former edge to control the power source of output and electric current through be in completely namely, can accomplish the constant current precision of 5% the most accurately, deputy edge needs simple output circuit only can. Former edge basically relies on the feedback of auxiliary edge to control output voltage, the control of resistor of support current limliting to former edge electric current, multiply the precision that exports electricity than control with circling at the same time. Former edge plan succeeded to keep apart what stimulate circuit instead a variety of advantages, the framework is simple at the same time, can accomplish minor volume and low cost, at present already predominate drive. The problem of constant current precision of former edge: Because the manufacturing precision of transformation is controlled hard, bring about former edge plan to be when transformer of use inferior quality, drift of output electric current is bigger. So, former edge plan increased deputy edge constant current to dominate circuit through improving, such although compare common former edge plan complex, but contrast dashs plan instead, OK still leave out smooth Ou, systematization price is compared highest. Ask according to the character of the regulation using phone of electrified wire netting and LED drive power source, choosing and the following should consider when power source of design LED drive: 1, high reliability is special the drive power source that resembles LED street lamp, install in headroom, maintenance is no-go, the expenses of maintenance is large also. 2, efficient 　 LED is energy-saving product, the efficiency of drive power source wants tall. Install the structure inside lamps and lanterns to power source, particularly important. Lift and drop of temperature as LED because of the glow efficiency of LED, so of LED medicinal powder heat is very important. The efficiency of power source is tall, its consume power is little, calorific inside lamps and lanterns amount is small, also reduced the temperature rise of lamps and lanterns. Advantageous to deferring the light of LED to decline. 3, element of power of high power element is the requirement of electrified wire netting to load. General 70 tile use electric equipment below, not mandatory index. Although power is not great individual with element of electric equipment power a bit lower not big to the influence of electrified wire netting, but everybody lights a lamp in the evening, congener load too concentration, can produce more serious pollution to electrified wire netting. To 30 made of baked clay ～ the LED drive power source of 40 tile, allegedly before long in the future, perhaps can have particular index demand to power element respect. 4, drive fashion is current now have two kinds: It is source of a constant voltage offers source of many constant current firstly, source of every constant current gives every LED power supply alone. This kind of means, combination is agile, all the way LED breakdown, do not affect the work of other LED, but cost is met slightly a bit taller. Another kind is power supply of direct constant current, LED establishs ties or paralell connection moves. Its advantage is cost a bit lower, but flexibility is poor, resolve trouble of a certain LED even, do not affect the issue that other LED runs. These two kinds of forms, coexist inside period of time. Multichannel constant current exports power supply way, can better in cost and performance side. Perhaps be direction of the following mainstream. 5, the ability that surge protects 　 LED to fight surge is poorer, fight retrorse voltage ability especially. The protection that strengthens this respect is very significant also. Some LED lamp installs outdoors, be like LED street lamp. Because electrified wire netting is opened ladenly,swing the induction with be struck by lightning, from electrified wire netting the system can invade all sorts of surge, some surge can cause the damage of LED. Because power source of this LED drive wants to those who restrain surge is invade, protective LED is not damaged ability. 6, the protection of protective function power source besides convention outside the function, LED temperature had better increase to lose feedback in constant current output, prevent LED temperature exorbitant. 7, defend be installed outside respect lamps and lanterns model, power source structure wants waterproof, moistureproof, crust should be able to bear or endure bask in. 8, the life of drive power source wants the life look with LED comfortable match. 9, should accord with bring the demand with compasses and compatible electromagnetism. The application as LED is increasingly wide, the function of LED drive power source will fit the requirement of LED more and more. CNC Milling