CN102548087A

CN102548087A - High-efficiency half-bridge LED illumination driving power source

Info

Publication number: CN102548087A
Application number: CN201010589639XA
Authority: CN
Inventors: 苟先太
Original assignee: CHENGDU SURESUN TECHNOLOGY Co Ltd
Current assignee: CHENGDU SURESUN TECHNOLOGY Co Ltd
Priority date: 2010-12-15
Filing date: 2010-12-15
Publication date: 2012-07-04

Abstract

A high-efficiency half-bridge LED illumination driving power source is capable of obviously improving reliability of a whole circuit and greatly prolonging the failure-free service life of an LED illumination lamp. The high-efficiency half-bridge LED illumination driving power source comprises a rectification circuit, a half-bridge conversion circuit, a current-limiting circuit and a high-frequency voltage-reducing rectification circuit which are in sequential connection, wherein the current-limiting circuit is serially connected at a direct communication position of two main switching tubes in the half-bridge conversion circuit. When the two switching tubes are in failure such as in a common-mode conducting state and the like due to various reasons, once current exceeds a certain set value, a switching tube in the current-limiting circuit is quickly cut off to enable the circuit not to form a loop, so that the problem that a circuit is destructively damaged due to common-mode conducting of the half-bridge conversion circuit is completed solved, reliability of the whole circuit is greatly improved, the service life of the whole driving power source can be truly matched with the super long service life of thousands of hours of the LED, and the high-efficiency half-bridge LED illumination driving power source is simple and inexpensive.

Description

A kind of high efficiency half-bridge formula LED illumination driving power

Technical field

The present invention relates to a kind of LED illuminating lamp, solved especially thoroughly that the common-mode conducting appears in semibridge system translation circuit easily and a kind of high efficiency half-bridge formula LED illumination driving power of sending a telegraph the crushing problem of damaging in road.

Background technology

At present; Known LED illuminating lamp majority has adopted the semi-bridge switching voltage regulator circuit; Characteristics such as it has high efficiency, volume is little and in light weight; But cause the semibridge system translation circuit and burn owing to the common-mode conducting appears in two main switching tubes in its circuit easily, cause that whole driving power functional reliability reduces, shorten useful life, cause at present the whole lamp of LED illuminating lamp on the market almost not reach minimum 35000 hours useful life.

Summary of the invention

In order to overcome the common-mode conducting appears in semi-bridge switching voltage regulator easily when working deficiency; The present invention provides a kind of high efficiency half-bridge formula LED illumination driving power; Characteristics such as this power supply not only has high efficiency, volume is little and in light weight, and thoroughly solved the semibridge system translation circuit and the common-mode conducting occurs and send a telegraph the crushing problem of damaging in road.

The technical solution adopted for the present invention to solve the technical problems is: directly connection place disconnection of two main switching tubes in the semibridge system translation circuit, seal in a current-limiting circuit, be communicated with two switching tubes through said current-limiting circuit.When the electric current when said two switching tubes the common-mode conducting occurs because of a variety of causes surpasses a certain set point; Switching tube in the said current-limiting circuit ends rapidly; Make circuit can not form a loop; Occur the common-mode conducting easily and send a telegraph the crushing problem of damaging in road thereby thoroughly solved the semibridge system translation circuit, improved the reliability of entire circuit greatly, make the life-span of whole driving power really can be complementary with tens thousand of hours extra long life of LED.

The particular circuit configurations of present technique scheme is shown in accompanying drawing: entire circuit is made up of rectification circuit, semibridge system translation circuit, current-limiting circuit and high frequency voltage descending rectification circuit.

Wherein, Rectification circuit is made up of four diode D1-D4; Civil power is through negative pole tie point 4 inputs of the anodal tie point 2 of said D1, D3 and D2, D4, and the negative pole tie point 1 of said D1, D3 is as the positive pole of entire circuit, and the anodal tie point 3 of said D2, D4 is as the negative pole of entire circuit.

Form the semibridge system translation circuit by components and parts such as resistance R 1, capacitor C 1, capacitor C 2, capacitor C 3, diac Q, switching tube Q1, switching tube Q2 and transformer B1.Its each components and parts are connected to: the upper end of said R1 is the electrode input end of this circuit, the upper end of the said C1 of following termination; The lower end of said C1 is the negative input of this circuit, the said R1 of the last termination of said C2 upper end, the upper end of the said C3 of following termination; Said C2 lower end is the output of this circuit, the lower end of the said C1 of following termination of said C3, and the left end of said Q is connected on the lower end of said R1, and right-hand member connects the B utmost point of said Q2; The C utmost point of said Q1 connects the upper end of said C2, and the B utmost point connects 1 end of said B1, and the E utmost point connects the C utmost point (being said Q1 and said Q2 unique direct connectivity points in circuit) of said Q2; The B utmost point of said Q2 connects 6 ends of said B1, and the E utmost point connects the lower end of said C3; The E utmost point of 2 ends of said B1, the said Q1 of 4 terminations, the E utmost point of the said Q2 of 5 terminations, 3 ends are another output of this circuit.

Current-limiting circuit is made up of biasing resistance R2, control triode Q3, sample resistance R3 and benchmark triode Q4.Wherein said R2 upper end is connected with the C utmost point of said Q3; And be this circuit input end; The lower end of said R1 connects the B utmost point of said Q3 and the C utmost point of said Q4 simultaneously; The E utmost point of said Q3 connects the B utmost point of said Q4 and the upper end of said R3 simultaneously, and the E utmost point of said Q4 connects the lower end of said R3 and as the output of this circuit.

High frequency voltage descending rectified current routing transformer B2, diode D5/D6 and capacitor C 4 constitute.Each components and parts of this circuit are connected to: 7 ends of said B2 and 8 ends are the input of this circuit, the positive pole of the said D5 of 9 terminations, and the lower end of the said C4 of 10 terminations, and as the cathode output end of this circuit, the positive pole of the said D6 of 11 terminations; The negative pole of said D5 is connected with the upper end of the negative pole of said D6, said C4 and as the cathode output end of this circuit simultaneously.

Then; Said tie point 1 and tie point 3 are connect said R1 upper end and said C1 lower end respectively; 7 ends of the said B2 of 3 terminations of said B1,8 of said B2 terminates at the lower end of said C2, so pulsating direct current just is input to the semibridge system translation circuit from rectification circuit; Deliver to the high frequency voltage descending rectification circuit again, thus output.But in order to overcome the common-mode conducting in the circuit; The present invention inserts a current-limiting circuit in the semibridge system translation circuit; Connected mode is: two switching tubes in the semibridge system translation circuit directly connection place break off, with the E utmost point of the said Q1 of last termination of said R2, the C utmost point of the said Q2 of following termination of said R3; So said current-limiting circuit just is connected between breakpoint, thereby connects two switching tubes through current-limiting circuit.When said Q1, Q2 the common-mode conducting occurs because of a variety of causes; The big electric current that produces this current-limiting circuit of to flow through; This moment, electric current made said Q3 conducting, thereby big electric current is added on said Q4 and the said R3, when the voltage that produces at said R3 arrives the conducting voltage of said Q4; Said Q4 conducting this moment makes said Q3 end rapidly.At this moment, said current-limiting circuit is in by off state, makes circuit can not form a loop, has thoroughly solved the semibridge system translation circuit and the common-mode conducting occurred and send a telegraph the crushing problem of damaging in road.

The useful effect of patent of the present invention is: have high efficiency, volume is little and advantage such as in light weight in; Also obviously improve the reliability of entire circuit work and prolong LED illuminating lamp no-failure life greatly, realized current-limiting function with the circuit very low cost that the utmost point is simplified.

Description of drawings

Accompanying drawing is the circuit theory diagrams of patent of the present invention.

Embodiment

Below in conjunction with embodiment the present invention is further specified:

Diode D1-D4 in the circuit all adopts 1N4007, resistance R 1=1 megohm, resistance R 2=0.5 ohm, resistance R 3=1 ohm; Capacitor C 1=1uF, capacitor C 2=0.1uF, capacitor C 3=0.1uF; Capacitor C 4=1uF, bidirectional trigger diode Q adopts DB4, and transformer B1 can adopt the annular high frequency magnetic core of 10X6X5; Its ratio is 7:2:2, and the turn ratio of transformer B2 is 5:1:1, and diode D5 and D6 all adopt FR107; Triode Q1 and Q2 all can adopt MJE13003, and triode Q3 can adopt 13001, and triode Q4 can adopt 8050.

Claims

1. high efficiency half-bridge formula LED illumination driving power; It is to be connected and composed in order by rectification circuit, semibridge system translation circuit, current-limiting circuit and high frequency voltage descending rectification circuit; It is characterized in that: directly connection place disconnection of two main switching tubes in the semibridge system translation circuit; Seal in said current-limiting circuit, be communicated with two main switching tubes through said current-limiting circuit.

2. high efficiency half-bridge formula LED illumination driving power according to claim 1; It is characterized in that: constitute current-limiting circuit by a switch triode, a control triode, a biasing resistance and a sample resistance; The upper end of wherein said biasing resistance is the input of this circuit; The C utmost point of said switch triode is connected with the biasing resistance upper end, and the lower end of said biasing resistance is connected with the B utmost point of switch triode, the C utmost point of control triode simultaneously, and the E utmost point of said switch triode is connected with the B utmost point of control triode, the upper end of sample resistance simultaneously; The E utmost point of said control triode and the lower end of sample resistance are connected, and as the output of this circuit.