CN204442775U

CN204442775U - A kind of controllable silicon light modulation LED drive circuit with compensating circuit

Info

Publication number: CN204442775U
Application number: CN201520117798.8U
Authority: CN
Inventors: 肖志蓝
Original assignee: Yongtai Electro-Optical Technology Inc (us) 62 Martin Road Concord Massachusetts 017 Of China Of Foshan City
Current assignee: Yongtai Electro-Optical Technology Inc (us) 62 Martin Road Concord Massachusetts 017 Of China Of Foshan City
Priority date: 2015-02-27
Filing date: 2015-02-27
Publication date: 2015-07-01
Anticipated expiration: 2025-02-27

Abstract

The utility model discloses a kind of controllable silicon light modulation LED drive circuit with compensating circuit, comprising input filter circuit, input rectifying filter circuit, circuit for power conversion, output rectifier and filter, feedback circuit and control chip IC, also including the compensating circuit for compensating drive circuit input alternating voltage.

Description

A kind of controllable silicon light modulation LED drive circuit with compensating circuit

Technical field

The utility model relates to LED light regulating technology field, refers in particular to a kind of controllable silicon light modulation LED drive circuit with compensating circuit.

Background technology

Along with market competition is more and more fierce, LED manufacturer starts the method for seeking the production cost reducing LED product.Market there is a kind of LED driver of the secondary constant-current circuit removed in traditional LED light adjusting circuit for this reason; The electric current of this LED driver by adopting the metal-oxide-semiconductor current sense resistor of primary side to detect primary side, utilization realizes the secondary constant current effect be similar to the control of electromotive power output, but this frame mode is perfect not enough, be embodied in: when fluctuation occurs LED drive current input AC voltage, LED output current also can produce fluctuation thereupon, such as when input AC voltage reduces,---LED circuit drives duty ratio to become large, and---primary side current becomes large---electromotive power output diminishes---LED output current and diminishes, and vice versa.

Summary of the invention

The purpose of this utility model is to overcome the deficiencies in the prior art, provide a kind of reasonable in design, structure simple, the controllable silicon light modulation LED drive circuit that can compensate LED drive circuit.

For achieving the above object, technical scheme provided by the utility model is: a kind of controllable silicon light modulation LED drive circuit with compensating circuit, comprising input filter circuit, input rectifying filter circuit, circuit for power conversion, output rectifier and filter, feedback circuit and control chip IC, it is characterized in that: also including the compensating circuit for compensating drive circuit input alternating voltage; This compensating circuit comprises resistance R7, R22, R11 and R14 and electric capacity C5, wherein resistance R7 one end is connected on the zero line circuit N between described input rectifying filter circuit and power conversion circuit, the other end is contacted successively and is connected with resistance R22 and R14, and be connected with the current detecting pin on control chip IC by one end of resistance R14, resistance R11 one end is connected between resistance R22 and R14 simultaneously, the other end is connected on the live wire circuit L between described input rectifying filter circuit and power conversion circuit, and electric capacity C5 is connected in parallel on resistance R11 two ends.

The utility model by setting up a compensating circuit in LED drive circuit, concrete comprises by resistance R7, R22, R11 and R14 and electric capacity C5, wherein resistance R7 one end is connected on the zero line circuit N between input rectifying filter circuit and power conversion circuit, the other end is contacted successively and is connected with resistance R22 and R14, and be connected with the current detecting pin on control chip IC by one end of resistance R14, resistance R11 one end is connected between resistance R22 and R14 simultaneously, the other end is connected on the live wire circuit L between input rectifying filter circuit and power conversion circuit, electric capacity C5 is connected in parallel on resistance R11 two ends, when the AC input terminal voltage in LED drive circuit reduces, the voltage at resistance R11 two ends also reduces accordingly, be positioned at the reduction of the voltage at resistance R14 two ends equally, and then reduced by the offset current I1 of the current detecting pin in the upper also ramp metering chip IC of resistance R14, but the output current I due to LED drive circuit is determined jointly by I1 and primary side current I2, namely output current I is determined jointly by I1 and I2 sum, but when AC input terminal voltage reduces, driving duty ratio in circuit becomes large, primary side current I2 increases, therefore when reducing appears in input AC voltage, circuit I 1 in circuit is caused to reduce accordingly, primary side current I2 increases, therefore I1 and I2 sum can remain substantially constant, thus ensure that output current I's is stable, in like manner when input AC voltage becomes large, output current I also by I1 and I2 change accordingly substantially remain unchanged make output current I maintain at steady state.

Accompanying drawing explanation

Fig. 1 is the operation principle block diagram in the utility model.

In figure: 1-input filter circuit, 2-input rectifying filter circuit, 3-power conversion circuit, 4-output rectifier and filter, 5-feedback circuit.

Embodiment

Below in conjunction with specific embodiment, the utility model is described in further detail:

Shown in accompanying drawing 1, the present embodiment provides a kind of controllable silicon light modulation LED drive circuit with compensating circuit, input filter circuit 1, input rectifying filter circuit 2, circuit for power conversion 3, output rectifier and filter 4, feedback circuit 5 and control chip IC should being comprised with the controllable silicon light modulation LED drive circuit of compensating circuit, also including the compensating circuit for compensating drive circuit input alternating voltage simultaneously; This compensating circuit comprises resistance R7, R22, R11 and R14 and electric capacity C5, wherein resistance R7 one end is connected on the zero line circuit N between input rectifying filter circuit 2 and power conversion circuit 3, the other end is contacted successively and is connected with resistance R22 and R14, and be connected with the current detecting pin on control chip IC by one end of resistance R14, resistance R11 one end is connected between resistance R22 and R14 simultaneously, the other end is connected on the live wire circuit L between input rectifying filter circuit 2 and power conversion circuit 3, and electric capacity C5 is connected in parallel on resistance R11 two ends.

During work, when the AC input terminal voltage in LED drive circuit reduces, the voltage at resistance R11 two ends also reduces accordingly, be positioned at the reduction of the voltage at resistance R14 two ends equally, and then reduced by the offset current I1 of the current detecting pin in the upper also ramp metering chip IC of resistance R14, but because the output current I of LED drive circuit is by I1 with jointly to be determined by the primary side current I2 of resistance R20, namely output current I is determined jointly by I1 and I2 sum, but when AC input terminal voltage reduces, driving duty ratio in circuit becomes large, primary side current I2 increases, therefore when reducing appears in input AC voltage, the electric current I 1 simultaneously flowed through in circuit on resistance R14 is caused to reduce accordingly and the primary side current I2 flowed through on resistance R20 increases, therefore I1 and I2 sum can remain substantially constant, thus ensure that output current I's is stable, in like manner when input AC voltage becomes large, the voltage at resistance R11 two ends also increases accordingly, be positioned at the increase of the voltage at resistance R14 two ends equally, and then increased by the offset current I1 of the current detecting pin in the upper also ramp metering chip IC of resistance R14, but because the output current I of LED drive circuit is by I1 with jointly to be determined by the primary side current I2 of resistance R20, namely output current I is determined jointly by I1 and I2 sum, but when AC input terminal voltage reduces, its driving duty ratio of drive circuit in circuit diminishes, primary side current I2 reduces, output current I also by I1 and I2 change accordingly substantially remain unchanged make output current I maintain at steady state.

In sum, this programme by increasing a set of compensating circuit in LED dimming driving circuit, can effectively prevent the change in voltage of circuit input end and cause the phenomenon that LED output current changes accordingly, avoid the phenomenon of LED output current instability, thus make it have good market efficiency.

The examples of implementation of the above are only the preferred embodiment of the utility model, not limit practical range of the present utility model with this, therefore the change that all shapes according to the utility model, principle are done, all should be encompassed in protection range of the present utility model.

Claims

1. the controllable silicon light modulation LED drive circuit with compensating circuit, comprising input filter circuit, input rectifying filter circuit, circuit for power conversion, output rectifier and filter, feedback circuit and control chip IC, it is characterized in that: also including the compensating circuit for compensating drive circuit input alternating voltage; This compensating circuit comprises resistance R7, R22, R11 and R14 and electric capacity C5, wherein resistance R7 one end is connected on the zero line circuit N between described input rectifying filter circuit and power conversion circuit, the other end is contacted successively and is connected with resistance R22 and R14, and be connected with the current detecting pin on control chip IC by one end of resistance R14, resistance R11 one end is connected between resistance R22 and R14 simultaneously, the other end is connected on the live wire circuit L between described input rectifying filter circuit and power conversion circuit, and electric capacity C5 is connected in parallel on resistance R11 two ends.