CN201207749Y

CN201207749Y - EEFL electric power having protection

Info

Publication number: CN201207749Y
Application number: CNU2008200237483U
Authority: CN
Inventors: 石汝军; 王善松
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-06-06
Filing date: 2008-06-06
Publication date: 2009-03-11
Anticipated expiration: 2018-06-06

Abstract

Disclosed is a EEFL power supply with protection, which belongs to the field of electronic lighting technology, comprising a full-bridge rectifier circuit, a filter circuit and a power supply protection circuit; the EEFL power supply is characterized in that the power supply also includes a special IC and a startup circuit thereof, a pulse transformer, an externally excited half-bridge circuit and a high-frequency output transformer. The full-bridge rectifier circuit, the filter circuit, the special IC and the startup circuit thereof, the pulse transformer, the externally excited half-bridge circuits and the high-frequency output transformer are sequentially connected; one end of the protection circuit is connected with the special IC and the startup circuit thereof, the other end is connected with the high-frequency output transformer; the protection circuit flickers during protection when over-voltage or under-voltage occurs and can be restored to normal work without switch when the voltage is recovered. The utility model can provide power for 5 - 20 EEFL fluorescent tubes with external electrode at the same time, the power can be saved by more than 20% at the same brightness and the service life is prolonged by one time. Meanwhile, the EEFL power supply has the advantages of stability in working, full protection function, high universality, easy production and debugging, high reliability and low manufacturing cost.

Description

A kind of EEFL power supply with protection

Technical field

The utility model relates to the electrical lighting technical field, further relates to external electrode fluorescence lamp EEFL, is specifically related to a kind of EEFL power supply with protection.

Background technology

External electrode fluorescence lamp, promptly EEFL lamp source is a kind of new-type light source, and is higher to its supporting high-frequency drive power requirement.EEFL power supply in the market, two kinds of main circuits of general employing, a kind of is to adopt self-excited oscillation type, the external import electric ballast chip of another kind of employing, the former is because of existing the shortcoming that can't overcome, can only be used in the small-power occasion, the advantage of EEFL fluorescent tube can not get performance, and its reliability is extremely low; The chip that the latter adopts is owing to adopt import electric ballast chip, and the not only product cost height of Zhi Zaoing, and fluorescent lamp is different with the operating characteristic of EEFL fluorescent tube, also can not get good effect.Simultaneously in actual applications because voltage fluctuation; present used EEFL power supply; be easy to damage at excessive rolling; though and in overvoltage or the protection of under-voltage circuit down; but the switch primary power source could start again; the lighting apparatus that this point was used at night is difficult to accomplish, has caused the unsurmountable weakness of existing power supply.

Publication number is that the Chinese patent of CN200620023731.9 discloses a kind of ballast and realizes that one drags many high-power energy-saving lamps; it comprises electric ballast, the fluorescent tube that is connected with resonant inductance; wherein resonant inductance is divided into multiple branches and connects a plurality of fluorescent tube co-operation; and in each loop, link to each other with electric ballast by protection device FU; integrated lamp power can be increased; the fluorescent tube manufacture difficulty also reduces simultaneously, and the influence that fault is caused is reduced to minimum.The used fluorescent tube of this patent is not the EEFL fluorescent lamp of external electrode.

Publication number is that the Chinese patent of CN200710138040.2 discloses a kind of EEFL type fluorescent lamp with efficiency optimization, the technical scheme of this invention is: design has outer casing shell and/or is positioned at (part) coating of outer casing shell inner surface, this outer casing shell and/or (part) coating provide low electron work functon preferably in the scope of 0eV＜Wa＜5eV, have therefore realized the optimization of efficient and the reduction of starting resistor.This patent does not relate to the EEFL power supply.

Can adopt special chip as 555 integrated circuits in the prior art; realized the energy-saving design of circuit, the protective circuit by adopting is worked line voltage between 150v～255v; overvoltage or under-voltage i.e. flicker protection, line voltage does not need switch to get final product operate as normal after recovering.

Summary of the invention

The purpose of this utility model provides the EEFL power supply of a kind of economize on electricity, band protection, band protection cheaply.

The technical solution of the utility model: a kind of EEFL power supply with protection, comprise full bridge rectifier, filter circuit and power supply protection circuit, it is characterized in that: also comprise application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit and high-frequency output transformer; Described full bridge rectifier, filter circuit, application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit are connected successively with high-frequency output transformer; described power supply protection circuit one end is connected with application-specific integrated circuit and start-up circuit thereof, and the other end is connected with high-frequency output transformer.Described protective circuit, in overvoltage or under-voltage i.e. flicker protection, voltage does not need switch to get final product operate as normal after recovering.

Further, described application-specific integrated circuit and start-up circuit thereof comprise one 555 chips and by a resistance and the start-up circuit that electric capacity is connected in series, described pulse transformer comprises an elementary winding and two secondary winding; Described independent-excited half-bridge circuit constitutes half-bridge by two switching tubes and is connected between the output plus terminal and negative terminal of full bridge rectifier; Described high-frequency output transformer comprises an input winding, an output winding and an auxiliary winding; The output negative terminal of the capacitance terminal of described start-up circuit and full bridge rectifier is connected, and resistance terminal is connected with the application-specific integrated circuit start end; The elementary winding of described pulse transformer is connected with the output of application-specific integrated circuit and the output negative terminal of full bridge rectifier respectively, and an end of the same name of two secondary winding connects the switching tube of independent-excited half-bridge circuit respectively; Another end of the same name is connected with the input winding of described high-frequency output transformer respectively; One end of described power supply protection circuit and the auxiliary winding of high-frequency output transformer are connected, and the feedback input end of the other end and application-specific integrated circuit is connected; The output winding output EEFL driving voltage of described high-frequency output transformer.

Described application-specific integrated circuit is that marque is 555 or serves as a kind of in the family chip of beginning with 3.For example: the employing marque is 3136,3237,3937 special chip.

The utility model has following advantage compared with the prior art:

1, the utility model economize on electricity, band protective circuit can be 5～20 EEFL external electrode fluorescence lamp pipes power supply are provided simultaneously, can economize on electricity more than 20% under equal brightness, prolong one times useful life.

2, the utility model adopts the independent-excited half-bridge circuit, and the application-specific integrated circuit peripheral circuit is simple, working stability, and defencive function is complete; highly versatile is produced debugging simply, the reliability height; low cost of manufacture is fit to Chinese national conditions very much, helps applying of EEFL lamp source.

Description of drawings

Fig. 1 is the utility model circuit block diagram;

Fig. 2 is the circuit diagram of embodiment of the present utility model.

Embodiment

The utility model is described in further detail below in conjunction with drawings and Examples.

In Fig. 1 circuit block diagram of the present utility model, the EEFL power supply of band protection comprises full bridge rectifier, filter circuit and power supply protection circuit, also comprises application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit and high-frequency output transformer; Described full bridge rectifier, filter circuit, application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit are connected successively with high-frequency output transformer, described power supply protection circuit one end is connected with application-specific integrated circuit and start-up circuit thereof, and the other end is connected with high-frequency output transformer;

The input line voltage is delivered to full bridge rectifier and is driven the EEFL power work, and EEFL power drives voltage exports external electrode fluorescence lamp EEFL fluorescent tube to through high-frequency output transformer.

Its operation principle:

The voltage that civil power 220V provides, behind the full-bridge circuit rectifying and wave-filtering, obtain comparatively galvanic current pressure, after the resistance step-down of application-specific integrated circuit start-up circuit, provide the startup power supply for the application-specific integrated circuit circuit, this application-specific integrated circuit includes the pulse square wave that oscillator produces frequency stabilization, and by the power amplification circuit in the oscillator square wave is exported, promote the independent-excited half-bridge circuit and carry out work; This application-specific integrated circuit periphery is provided with power supply protection circuit, and line voltage is worked between 150v～255v, overvoltage or under-voltage i.e. flicker protection, and line voltage recovers not need switch to get final product operate as normal behind 150v～255v.

In the circuit diagram of Fig. 2 embodiment of the present utility model:

Described application-specific integrated circuit and start-up circuit thereof comprise one 555 chips and by a resistance and the start-up circuit that electric capacity is connected in series, described pulse transformer comprises an elementary winding and two secondary winding; Described independent-excited half-bridge circuit constitutes half-bridge by two switching tubes and is connected between the output plus terminal and negative terminal of full bridge rectifier; Described high-frequency output transformer comprises an input winding, an output winding and an auxiliary winding; The output negative terminal of the capacitance terminal of described start-up circuit and full bridge rectifier is connected, and resistance terminal is connected with the application-specific integrated circuit start end; The elementary winding of described pulse transformer is connected with the output of application-specific integrated circuit and the output negative terminal of full bridge rectifier respectively, and an end of the same name of two secondary winding connects the switching tube grid of independent-excited half-bridge circuit respectively; Another end of the same name is connected with the input winding of described high-frequency output transformer respectively; One end of described power supply protection circuit and the auxiliary winding of high-frequency output transformer are connected, and the feedback input end of the other end and application-specific integrated circuit is connected; The output winding output EEFL driving voltage of described high-frequency output transformer.

Behind the big capacitor filtering of line voltage process full-bridge circuit rectification, provide starting current through dropping resistor for application-specific integrated circuit, behind the startup threshold values in starting resistor is higher than chip, oscillating circuit is just started working (after finishing startup, start-up circuit is just deactivated, and starts up to next time and arrives).Because oscillatory work voltage is taken from the reference power supply of IC inside, therefore be not subjected to the influence of mains ripple and variation of ambient temperature, the operating frequency error only depends on foozle and the temperature coefficient of oscillation resistance RT and oscillation resistance CT and IC, thereby operating frequency is highly stable.The power supply of IC is taken from the auxiliary winding of output transformer, behind the high-frequency diode rectifying and wave-filtering, for IC provides working power.The vibration output waveform is through the totem output circuit pulse transformer of IC inside, the switching tube up and down that drives the half-bridge arm respectively advances conducting and shutoff in turn, form the square-wave voltage of 50KHz, through high-frequency output transformer voltage is risen to the high-frequency and high-voltage that peak value is 1500v again, promote the EEFL fluorescent tube and carry out work.

The input signal of power supply protection circuit is taken from the auxiliary winding of high pressure output transformer; form a feedback voltage,, line voltage is worked between 150v～255v the protective circuit power supply; overvoltage or under-voltage i.e. flicker protection, line voltage does not need switch to get final product operate as normal after recovering.

Embodiment 1

After the de-noising of civil power 220V process EMC circuit, add to full bridge rectifier, through electrolytic capacitor filter C, obtain the direct voltage of comparatively stable about 300V, as the main power source of entire circuit work.This power supply is connected to 7 pin of IC by dropping resistor R, and for IC provides starting current, behind the startup threshold values in starting resistor is higher than chip, 8 pin of IC are just exported the reference voltage of 5v, and oscillating circuit is just started working, and used integrated circuit (IC) chip is 555 chips.After the Digital Logical Circuits of oscillating impulse in IC handled after interior view is risen circuit is 50% pulse square wave by the 6 pin output duty cycles of IC, through the phase-splitting of pulse transformer isolation, the switching tube up and down that drives half-bridge circuit respectively is (because the IC drive current is big, so need not to add in addition drive circuit), thereby direct current that will about 300V forms the about 150V of peak value at the high-frequency output transformer input, frequency is the high-frequency alternating current of 50KHZ, boosts to 1500v promotion EEFL fluorescent tube through high-frequency output transformer again and carries out work; Auxiliary simultaneously winding also produces the pulse ac voltage of the about 30v of peak-to-peak value, and this voltage also is added in 7 pin of IC through the high-frequency diode halfwave rectifier behind the capacitor filtering, and for IC provides working power, start-up circuit no longer works.

The input signal of protective circuit is taken from the auxiliary winding of high pressure output transformer; form a feedback voltage; the operating state of this voltage and output is closely related; this characteristic of this circuit utilizing has cleverly realized output open circuit, short circuit and civil power overvoltage protection; defencive function in conjunction with IC inside; make line voltage energy operate as normal between 150v～255v, overvoltage or under-voltage i.e. flicker protection, line voltage does not need switch to get final product operate as normal after recovering.

The integrated circuit (IC) chip of present embodiment also can adopt 3136,3237,3937 be equal to alternative.

Claims

1, a kind of EEFL power supply with protection comprises full bridge rectifier, filter circuit and power supply protection circuit, it is characterized in that: also comprise application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit and high-frequency output transformer; Described full bridge rectifier, filter circuit, application-specific integrated circuit and start-up circuit thereof, pulse transformer, independent-excited half-bridge circuit are connected successively with high-frequency output transformer, described power supply protection circuit one end is connected with application-specific integrated circuit and start-up circuit thereof, and the other end is connected with high-frequency output transformer; Described protective circuit, in overvoltage or under-voltage i.e. flicker protection, voltage does not need switch to get final product operate as normal after recovering.

2, the EEFL power supply of band protection according to claim 1, it is characterized in that: described application-specific integrated circuit and start-up circuit thereof comprise one 555 chips and by a resistance and the start-up circuit that electric capacity is connected in series, described pulse transformer comprises an elementary winding and two secondary winding; Described independent-excited half-bridge circuit constitutes half-bridge by two switching tubes and is connected between the output plus terminal and negative terminal of full bridge rectifier; Described high-frequency output transformer comprises an input winding, an output winding and an auxiliary winding; The output negative terminal of the capacitance terminal of described start-up circuit and full bridge rectifier is connected, and resistance terminal is connected with the application-specific integrated circuit start end; The elementary winding of described pulse transformer is connected with the output of application-specific integrated circuit and the output negative terminal of full bridge rectifier respectively, and an end of the same name of two secondary winding connects the switching tube of independent-excited half-bridge circuit respectively; Another end of the same name is connected with the input winding of described high-frequency output transformer respectively; One end of described power supply protection circuit and the auxiliary winding of high-frequency output transformer are connected, and the feedback input end of the other end and application-specific integrated circuit is connected; The output winding output EEFL driving voltage of described high-frequency output transformer.

3, the EEFL power supply of band according to claim 1 and 2 protection is characterized in that, described application-specific integrated circuit is that marque is 555 or serve as to start a kind of in the family chip with 3.