CN202385338U

CN202385338U - LED drive power supply

Info

Publication number: CN202385338U
Application number: CN2011204788129U
Authority: CN
Inventors: 武云祥; 潘成前
Original assignee: Changzhou Jutai Electronic Co Ltd
Current assignee: Changzhou Jutai Electronic Co Ltd
Priority date: 2011-11-28
Filing date: 2011-11-28
Publication date: 2012-08-15
Anticipated expiration: 2021-11-28

Abstract

The utility model discloses a LED drive power supply, comprising a rectification circuit for conversing an input alternative current into a direct current to output; a filter circuit for filtering the signal output from the rectification circuit and composed of a resistor and a capacitor, wherein the capacitor is a CBB capacitor and/or ceramic patch capacitor; a transformer for conversing the high voltage output from the filter circuit into the lower voltage; a peak absorption circuit for absorbing electric energy released from a transformer primary winding; a rectification filter circuit for rectifying and filtering a voltage signal output from the transformer; and a controller for controlling the switch off and switch on of the transformer using the output signal of the sample transformer. The LED drive power supply has advantages of high efficiency, low cost, simple circuit and safe and reliable performance.

Description

The LED driving power

Technical field

The utility model relates to lighting technical field, particularly a kind of LED driving power.

Background technology

Under the background that the worry of current global energy shortage raises once again; Energy savings is the important problem that we shall face future, and at lighting field, the application of LED luminous product is just attracting common people's sight; LED must be a developing tendency in future as a kind of novel green light source product.Various countries certification authority is to having made clearly regulation the useful life of LED, and V.1.1 ENERGY STAR solid-state illumination efficiency standard has stipulated the shortest Shi with Shou Ming – lumen depreciation, L70: home lighting 25000 hours; Commercial lighting 35000 hours.Distinguishing feature of LED is exactly the long-life, but the long-life factor of restriction LED is exactly a driving power.The LED driving power that uses at present; Its components and parts that comprise have photoelectrical coupler and electrochemical capacitor, are optical coupler and high-pressure electrolysis electric capacity and low-voltage electrolysis electric capacity owing to be prone to impaired element most in the driving power, therefore; After existing driving power used a period of time, situation about damaging appearred.

Summary of the invention

The utility model provides long LED driving power of a kind of life-span to the deficiency of prior art, the utlity model has high efficiency, low cost, circuit is simple, performance is safe and reliable advantage.

The utility model is realized through following technical scheme:

Comprise rectification circuit, convert the alternating current of importing into direct current output; And

Filter circuit, the signal that rectification circuit is exported filters, the filter circuit that this filter circuit is made up of resistance and electric capacity, wherein electric capacity is CBB electric capacity and/or ceramic paster electric capacity; And

Transformer, the high-voltage variable that will come from filter circuit output is changed to low-voltage; And

Spike absorbs circuit, absorbs the electric energy that the primary winding discharges; And

Current rectifying and wave filtering circuit, the voltage signal that transformer is exported carries out rectification and filtering; And

Control circuit, the output signal of sampling transformer carries out reserves to transformer and controls with releasing energy.

Adopted such scheme; The circuit of the power supply of the utility model has adopted the reverse exciting topological with the control of former limit; Output can provide two kinds of patterns of constant pressure and flow to satisfy the reliability requirement that LED drives, and under the situation that does not adopt photoelectrical coupler, the operating frequency of whole driving power improves; And electric capacity adopts CBB electric capacity and ceramic paster electric capacity, makes the life-span of driving power be able to prolong.

Control chip is the control chip of OB2520, not only can optimize the peripheral component of circuit, and control chip employing PFM control mode, can effectively raise the efficiency, and control chip also provides short-circuit protection simultaneously, and overvoltage protection has increased the fail safe of power supply.

Below in conjunction with accompanying drawing and practical implementation formula the utility model is further specified.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Embodiment

With reference to Fig. 1, the LED driving power, by rectification circuit, filter circuit, transformer, current rectifying and wave filtering circuit and control circuit are formed.

Rectification circuit converts the alternating current of input into direct current output, the bridge rectifier that rectification circuit is made up of diode D1, diode D2, diode D3, diode D4.

Filter circuit filters the signal of rectification circuit output, the filter circuit that this filter circuit is made up of inductance and electric capacity, and wherein electric capacity is CBB electric capacity and/or ceramic paster electric capacity.Filter circuit comprises first inductance L 1, second inductance L 2, first capacitor C 1 and second capacitor C 2; The two ends of first inductance L 1 are connected with an end of first electric capacity and second electric capacity respectively, and the other end of first capacitor C 1 and second capacitor C 2 is connected second inductance L, 2 two ends respectively.

Transformer T1, the high-voltage variable that will come from filter circuit output is changed to low-voltage.What transformer T1 adopted is the framework of inverse-excitation type, in the stage that transformer begins electricly, and when elementary winding one end of transformer is a positive voltage, when the other end is negative voltage, electrically electrically opposite with elementary winding two ends at the two ends of Secondary winding of transformer.

Spike absorbs circuit and absorbs the electric energy that the primary winding discharges.Spike absorbs the two ends that circuit is connected the elementary winding of transformation end.Spike absorbs circuit and comprises second resistance R 2, the 3rd capacitor C 3 and the 5th diode D5, and second resistance R 2 then is connected with the cathode terminal of the 5th diode D5 with 3 parallel connections of the 3rd capacitor C.When transformer is carrying out energy when discharging, electric current absorbs circuit through spike and circulates, and the energy that accumulates on the primary winding the most at last consumes.

Current rectifying and wave filtering circuit carries out rectification and filtering to the voltage signal of transformer T1 output.Current rectifying and wave filtering circuit is connected the two ends of transformer secondary output winding.Current rectifying and wave filtering circuit comprises rectifier diode D5 and the 6th capacitor C 6, the 7th capacitor C 7, the 8th capacitor C 8, the 9th capacitor C 9, and the 6th capacitor C 6 of the cathode terminal of rectifier diode D5 and parallel connection, the 7th capacitor C 7, the 8th capacitor C 8, the 9th capacitor C 9 are connected.The 6th capacitor C 6, the 7th capacitor C 7, the 8th capacitor C 8, the 9th capacitor C 9 are CBB electric capacity and/or ceramic paster electric capacity, help prolonging the life-span of power supply.

The output signal of control circuit sampling transformer T1 carries out reserves to transformer and controls with releasing energy.Control circuit comprises sample circuit; The output signal of sampling transformer; The secondary coil Ns sampled output signal (high/low) of this transformer of Nr coil coupling through transformer. sample circuit is made up of the 4th resistance R 4 and the 5th resistance R 5 of series connection, and the signal of sampling outputs to control chip IC from the node of the 4th resistance R 4 and the 5th resistance R 5.Control chip IC sends switching signal according to the signal of sample circuit, and this control chip is the OB2520 cake core.And control switch Q1, the switching signal of control chip IC is transmitted or blocked, control switch is a metal-oxide-semiconductor, the output of this control switch connects an end of the elementary winding of transformer.And power supply circuits; The voltage of filter circuit output charges to power supply circuits through resistance R 1 back; Power supply circuits provide the work required voltage to control chip, and these power supply circuits are made up of the 4th capacitor C 4 and the 5th capacitor C 5 that are connected in parallel between filter circuit and the ground.

Claims

1.LED driving power is characterized in that, comprises rectification circuit, converts the alternating current of importing into direct current output; And

2. LED driving power according to claim 1; It is characterized in that; Said filter circuit comprises first inductance, second inductance, first electric capacity and second electric capacity; The two ends of first inductance are connected with an end of first electric capacity and second electric capacity respectively, and the other end of first electric capacity and second electric capacity is connected the second inductance two ends respectively.

3. LED driving power according to claim 1 is characterized in that, said spike absorbs circuit and comprises second resistance, the 3rd electric capacity and the 5th diode, is connected with the cathode terminal of the 5th diode after second resistance and the 3rd electric capacity parallel connection.

4. LED driving power according to claim 1; It is characterized in that; Said current rectifying and wave filtering circuit comprises rectifier diode and the 6th electric capacity, the 7th electric capacity, the 8th electric capacity, the 9th electric capacity, and the cathode terminal of rectifier diode is connected with the 6th electric capacity, the 7th electric capacity, the 8th electric capacity, the 9th electric capacity of parallel connection.

5. LED driving power according to claim 1 is characterized in that said control circuit comprises sample circuit, the output signal of sampling transformer; And

Control chip sends switching signal according to the signal of sample circuit; And

Control switch transmits or blocks the switching signal of control chip.

6. LED driving power according to claim 5 is characterized in that, said sample circuit is made up of the 4th resistance and the 5th resistance of series connection.

7. LED driving power according to claim 5 is characterized in that, said control circuit also comprises power supply circuits, and these power supply circuits are made up of the 4th electric capacity and the 5th electric capacity that are connected in parallel between filter circuit and the ground.

8. LED driving power according to claim 5 is characterized in that, said control chip is the OB2520 cake core.

9. LED driving power according to claim 5 is characterized in that, said control switch is a metal-oxide-semiconductor.