CN202276500U

CN202276500U - Constant current light-emitting diode (LED) power supply without external metal oxide semiconductor field effect transistor (MOSFET)

Info

Publication number: CN202276500U
Application number: CN2011203308849U
Authority: CN
Inventors: 吕国峰; 周梅凤
Original assignee: Yixing Hongli Lamp Pole & Lamp Co Ltd
Current assignee: Hongli Lighting Group Co., Ltd.
Priority date: 2011-09-05
Filing date: 2011-09-05
Publication date: 2012-06-13
Anticipated expiration: 2021-09-05

Abstract

The utility model relates to a constant current light-emitting diode (LED) power supply without an external metal oxide semiconductor field effect transistor (MOSFET), which comprises an electro-magnetic interference/ electro magnetic compatibility (EMI/EMC) module and a bridge type rectifier module sequentially connected, and the output end of the bridge type rectifier module sequentially passes through a switch power supply direct current-direct current (DC-DC) conversion module and a constant current voltage limiting control module to be connected with an LED light source. A metal oxide semiconductor field (MOS) transistor and related driving circuits are omitted, so that production cost and failure rate of a controller are reduced. A VIPER12A chip integrates a pulse-width modulation (PWM) controller and a high voltage power MOSFET on the same chip so that the external MOSFET and a driving circuit are omitted and cost is reduced. Service life of products is prolonged by omitting a high voltage electrolytic capacitor. By adopting constant current and voltage limiting circuits, output current is led to be constant, current accuracy can reach +/-3%, and simultaneously voltage limiting is achieved.

Description

The constant-current LED power supply that does not have external MOSFET

Technical field

The utility model relates to a kind of LED lamp power supply, especially a kind of constant-current LED power supply that does not have external MOSFET.

Background technology

LED is as a kind of brand-new lighting system, and it is long to have a life-span, and it is low to consume energy; No mercury pollution; Remarkable advantage such as applying flexible and be regarded as the 21 century lighting source, and in power-saving technology cry surging today, the development main flow that the LED illumination becomes lighting technology has become common recognition.For performance and the minimizing failure rate of giving full play to the LED lighting device, used driving power fibrous root designs according to the LED self-characteristic.The LED power supply becomes the guarantee of LED industrial chain development; The quality of LED power supply has directly restricted the LED reliability of products; Because the LED responsive semiconductor device that is characteristic has negative temperature characteristic again, thereby in application process, need stablize and protect its operating state.The LED device to the requirement of driving power very He carve, LED is different from common blank sheet of paper bulb, can directly connect the alternating current of 220V.LED is by the low-voltage driving of 2～3V, translation circuit that must complex design; And the LED lamp of different purposes also need be equipped with different power supply adaptors.On the international market, efficient conversion, effective power, constant current accuracy, power source life, the electromagnetic compatibility requirements of the external LED of client team power supply are all very high.Because power supply has as about as the heart at whole light fixture, designs a good power supply and must integrate and take all factors into consideration each factor.

Yet what be worth worry is that under the background of market a slice prosperity, the LED product quality is very different, and causes the demand of driving power chaotic.Under the market LED product developing state like a raging fire; With regard to LED power supply enterprise; Be faced with the challenge of product itself at present: at first be that the drive circuit bulk life time is not long, especially Primary Component such as electric capacity, at high temperature the life-span of electric capacity directly has influence on the life-span of power supply; Next is that the conversion efficiency of LED power supply is low excessively, and from the present market demand, led driver need be challenged higher conversion efficiency, is all the more so driving great power LED especially, because all do not dissipate as heat as the power of light output.This not only causes the lifetime of LED itself, has also caused the poor efficiency of power source conversion simultaneously, has influenced the performance of LED energy-saving effect.Simultaneously, a lot of in the market like products exist huge defective, stroboscopic for example, phenomenon such as power factor is low.

The traditional Switching Power Supply conceptual design circuit of the general employing of existing LED power supply need be used external metal-oxide-semiconductor and high-pressure electrolysis electric capacity, and the control of output constant voltage.

Traditional way will exchange input rectifying earlier and become Vbus1, and high-pressure electrolysis electric capacity E1 voltage regulation filtering is adopted in Vbus1 output back.Through traditional DC-DC switching power circuit, such as UC3842 etc., can change HVDC Vbus1 into needed low-voltage direct Vs through transformer, Vs through the voltage stabilizing of TL431 etc., just obtains the needed Vout of load again.

There is following problem in traditional circuit:

1, cost is high, and the life-span is short.The way of conventional switch power supply need be on major loop, external metal-oxide-semiconductor, and increase the respective drive circuit, product cost is increased.Simultaneously Vbus1 adopts the filtering of high-pressure electrolysis capacitance voltage stabilizing at the back, because of electrochemical capacitor under high pressure, high temperature, electrolyte is volatile, the life-span is short, causes the entire controller lost of life.

2, constant current weak effect.The conventional switch power supply generally adopts constant voltage control, the LED lamp under the constant voltage, and the minor fluctuations of voltage all can cause the bigger variation of electric current.Current fluctuation is big, can directly influence intensity of illumination and the useful life of LED.

Summary of the invention

Goal of the invention: the purpose of the utility model is in order to overcome deficiency of the prior art, a kind of constant-current LED power supply that does not have external MOSFET to be provided.

Technical scheme: the constant-current LED power supply of the described no external MOSFET of the utility model; Comprise the EMI/EMC module, the bridge rectifier module that link to each other successively; The output of said bridge rectifier module through Switching Power Supply DC-DC modular converter, constant current pressure limiting control module, is connected to led light source successively at last.

Said Switching Power Supply DC-DC modular converter comprises VIPER12A chip IC 1, and the DRAIN pin of this VIPER12A chip IC 1 connects the high level Vbus1 that the bridge rectifier module is exported, the SOURCE pin ground connection of VIPER12A chip IC 1 through transformer main winding NP; Transformer is assisted winding Naux one end ground connection, and the other end connects said Vcc1 pin through diode D1, and said Vcc 1 pin is simultaneously through capacitor C 2 ground connection, and the FB pin of said VIPER12A chip IC 1 is connected with said constant current pressure limiting control circuit through optocoupler IC2.

Said constant current pressure limiting control circuit comprises triode Q1 and voltage stabilizing didoe D3; Transformer secondary output winding Ns one end ground connection; The other end provides direct voltage Vs through the current rectifying and wave filtering circuit that the second diode D2 and electrochemical capacitor E2 form; This direct voltage Vs connects 1 pin of optocoupler IC1 through first resistance R 1; 2 pin of said optocoupler IC1 connect the negative pole of voltage stabilizing didoe D3 and the collector electrode C of said triode Q1, the equal ground connection of emitter E of the positive pole of said voltage stabilizing didoe D3 and said triode Q1, and the base stage B of said triode Q1 is through second resistance R, 2 ground connection; The base stage B of said direct voltage Vs and said triode Q1 is connected on said led light source two ends and supplies power to led light source.

Connect first capacitor C 1 between two outputs of said bridge rectifier module, this first capacitor C 1 is a solid capacitor.

Beneficial effect: the utility model compared with prior art, its remarkable advantage is:

1, cancels external metal-oxide-semiconductor and associated driver circuitry, reduced the production cost and the failure rate of controller.Because of VIPER12A chipset PWM controller and high-voltage power MOSFET on same chip, so saved external MOSFET and drive circuit, cost is reduced.Through cancellation high-pressure electrolysis electric capacity, improved product useful life.

2, through adopting the circuit of constant current and pressure limiting, making the output constant current, current precision can reach ± and 3%, pressure limiting simultaneously.

Description of drawings

Fig. 1 is the circuit module sketch map of the utility model;

Fig. 2 is the circuit theory diagrams of the utility model.

Embodiment

As illustrated in figs. 1 and 2; The constant-current LED power supply of the described no external MOSFET of the utility model; Comprise the EMI/EMC module, the bridge rectifier module that link to each other successively; The output of said bridge rectifier module through Switching Power Supply DC-DC modular converter, constant current pressure limiting control module, is connected to led light source successively at last; Said Switching Power Supply DC-DC modular converter comprises VIPER12A chip IC 1, and the DRAIN pin of this VIPER12A chip IC 1 connects the high level Vbus1 that the bridge rectifier module is exported, the SOURCE pin ground connection of VIPER12A chip IC 1 through transformer main winding NP; Transformer is assisted winding Naux one end ground connection, and the other end connects said Vcc1 pin through diode D1, and said Vcc1 pin is simultaneously through capacitor C 2 ground connection, and the FB pin of said VIPER12A chip IC 1 is connected with said constant current pressure limiting control circuit through optocoupler IC2; Said constant current pressure limiting control circuit comprises triode Q1 and voltage stabilizing didoe D3; Transformer secondary output winding Ns one end ground connection; The other end provides direct voltage Vs through the current rectifying and wave filtering circuit that the second diode D2 and electrochemical capacitor E2 form; This direct voltage Vs connects 1 pin of optocoupler IC1 through first resistance R 1; 2 pin of said optocoupler IC1 connect the negative pole of voltage stabilizing didoe D3 and the collector electrode C of said triode Q1, the equal ground connection of emitter E of the positive pole of said voltage stabilizing didoe D3 and said triode Q1, and the base stage B of said triode Q1 is through second resistance R, 2 ground connection; The base stage B of said direct voltage Vs and said triode Q1 is connected on said led light source two ends and supplies power to led light source; Connect first capacitor C 1 between two outputs of said bridge rectifier module, this first capacitor C 1 is a solid capacitor.The utility model is cancelled external metal-oxide-semiconductor and associated driver circuitry, has reduced the production cost and the failure rate of controller.Because of VIPER12A chipset PWM controller and high-voltage power MOSFET on same chip, so saved external MOSFET and drive circuit, cost is reduced.Through cancellation high-pressure electrolysis electric capacity, improved product useful life; Through adopting the circuit of constant current and pressure limiting, make the output constant current, current precision can reach ± and 3%, the while pressure limiting.

Claims

1. the constant-current LED power supply that does not have external MOSFET; Comprise the EMI/EMC module, the bridge rectifier module that link to each other successively; It is characterized in that: the output of said bridge rectifier module through Switching Power Supply DC-DC modular converter, constant current pressure limiting control module, is connected to led light source successively at last.

2. according to the constant-current LED power supply of the said no external MOSFET of claim 1; It is characterized in that: said Switching Power Supply DC-DC modular converter comprises VIPER12A chip IC 1; The DRAIN pin of this VIPER12A chip IC 1 connects the high level Vbus1 that the bridge rectifier module is exported, the SOURCE pin ground connection of VIPER12A chip IC 1 through transformer main winding NP; Transformer is assisted winding Naux one end ground connection, and the other end connects said Vcc1 pin through diode D1, and said Vcc1 pin is simultaneously through capacitor C 2 ground connection, and the FB pin of said VIPER12A chip IC 1 is connected with said constant current pressure limiting control circuit through optocoupler IC2.

3. according to the constant-current LED power supply of the said no external MOSFET of claim 1; It is characterized in that: said constant current pressure limiting control circuit comprises triode Q1 and voltage stabilizing didoe D3; Transformer secondary output winding Ns one end ground connection; The other end provides direct voltage Vs through the current rectifying and wave filtering circuit that the second diode D2 and electrochemical capacitor E2 form, and this direct voltage Vs connects 1 pin of optocoupler IC1 through first resistance R 1, and 2 pin of said optocoupler IC1 connect the negative pole of voltage stabilizing didoe D3 and the collector electrode C of said triode Q1; The equal ground connection of the emitter E of the positive pole of said voltage stabilizing didoe D3 and said triode Q1, the base stage B of said triode Q1 is through second resistance R, 2 ground connection; The base stage B of said direct voltage Vs and said triode Q1 is connected on said led light source two ends and supplies power to led light source.

4. according to the constant-current LED power supply of the said no external MOSFET of claim 1, it is characterized in that: connect first capacitor C 1 between two outputs of said bridge rectifier module, this first capacitor C 1 is a solid capacitor.