CN204168543U

CN204168543U - A kind of LED driver

Info

Publication number: CN204168543U
Application number: CN201420574830.0U
Authority: CN
Inventors: 华桂潮
Original assignee: Led One Hangzhou Co Ltd
Current assignee: Inventronics Hangzhou Co Ltd; Led One Hangzhou Co Ltd
Priority date: 2014-09-30
Filing date: 2014-09-30
Publication date: 2015-02-18
Anticipated expiration: 2024-09-30

Abstract

The utility model provides a kind of LED driver, described LED driver comprise export initialization circuit, at least one can on-off component and the first terminal; Export output voltage values and/or the output current value of initialization circuit setting LED driver; The first terminal is used for reception control signal; At least one can on-off component be used for being in expendable path or off state under control of the control signal; At least one can the path of on-off component or off state, and association exports the circuit parameter for the output voltage values and/or output current value that set LED driver in initialization circuit, is worth most or output current is worth most with the output voltage associating LED driver.Visible the utility model can the path of on-off component or off state by changing at least one, change the circuit parameter exported in initialization circuit, thus the output changing LED driver is worth, and decreases the restriction to LED driver application scenario most.

Description

A kind of LED driver

Technical field

The utility model relates to optical drive field, especially relates to a kind of LED driver.

Background technology

At present, LED driver has multiple output current (or output voltage) specification usually.Such as can not the LED driver of light modulation, output current may have 350mA to 4A totally 10 specifications.Again such as, for the LED driver of tunable optical, a kind of output current adjustable range of specification is 0-350mA, and the output current adjustable range of another kind of specification may be 0-4A.

But be no matter the LED driver for tunable optical, or for can not the LED driver of light modulation, it exports value (output voltage is worth most or output voltage is worth most) be all constant.Be such as the Dimmable LED driver of 0-350mA for output current adjustable range, its lowest high-current value that can export is exactly 350mA.And if when a certain application scenario requires that output current is greater than 350mA, then this LED driver cannot satisfy the demands.Obviously, because the output of these LED drivers is worth immutable most, the application scenario that LED driver can be suitable for is limited.

Utility model content

The technical problem that the utility model solves is to provide a kind of LED driver, to realize reducing the restriction to the application scenario of LED driver.

For this reason, the technical scheme of the utility model technical solution problem is:

The utility model provides a kind of LED driver, comprising: export initialization circuit, at least one can on-off component and the first terminal; Described output initialization circuit sets output voltage values and/or the output current value of described LED driver;

Described the first terminal is used for reception control signal;

Described at least one can on-off component be used for be in expendable path or off state under the control of said control signal;

Described at least one can the path of on-off component or off state, associate the circuit parameter for the output voltage values and/or output current value that set described LED driver in described output initialization circuit, to be worth most with the output voltage associating described LED driver or output current is worth most.

Known by technique scheme, the LED driver of the utility model embodiment comprises output initialization circuit, at least one can on-off component and the first terminal, wherein the first terminal is used for reception control signal, at least one can be made on-off component can be in expendable path or off state, and at least one can the path of on-off component or off state, be associated with the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, thus the output voltage of association LED driver is worth most or output current is worth most, therefore the utility model embodiment can the path of on-off component or off state by changing at least one, change the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, thus the output voltage that can change LED driver is worth most or output current is worth most, achieve output voltage in visible the utility model embodiment to be worth most or output current is worth adjustable LED driver most, decrease the restriction of the application scenario to LED driver.

Accompanying drawing explanation

The structural representation of a kind of embodiment of the LED driver that Fig. 1 provides for the utility model embodiment;

The structural representation of the another kind of embodiment of the LED driver that Fig. 2 provides for the utility model embodiment;

Fig. 3 for the utility model embodiment provide can a kind of preferred structure of on-off component.

The structural representation of the another kind of embodiment of the LED driver that Fig. 4 provides for the utility model embodiment;

The structural representation of the another kind of embodiment of the LED driver that Fig. 5 provides for the utility model embodiment;

Fig. 6 be LED driver only include one can on-off component time structural representation;

Fig. 7 be LED driver comprise two can on-off component time structural representation;

The schematic flow sheet of a kind of embodiment of the method that Fig. 8 provides for the utility model embodiment;

The schematic flow sheet of the another kind of embodiment of the method that Fig. 9 provides for the utility model embodiment.

Embodiment

At present, LED driver has multiple output current (or output voltage) specification usually, such as can not the LED driver of light modulation, especially for the LED driver (such as power output is 100W) that power output is identical, output current may have 350mA to 4A totally 10 specifications; Or output voltage may have 30V to 100V totally 10 specifications.Again such as, for the LED driver of tunable optical, be the LED driver (such as power output is 100W) that power output is identical equally, a kind of output current adjustable range of specification is 0-350mA, and the output current adjustable range of another kind of specification may be 0-4A.

But be no matter the LED driver for tunable optical, or for can not the LED driver of light modulation, it exports value (output current is worth most or output voltage is worth most) be all constant.Be such as the Dimmable LED driver of 0-350mA for output current adjustable range, its lowest high-current value that can export is exactly 350mA.And if when a certain application scenario requires that output current is greater than 350mA, then this LED driver cannot satisfy the demands.Again such as the Dimmable LED driver that output current adjustable range is 0-4A, dim signal makes output current change between 0-4A, but when a certain application scenario only needs output current to change between 0-350mA, so the Dimmable LED driver of 0-4A certainly will too coarse adjustment during light modulation between 0-350mA, namely directly 350mA may be jumped to from 0A, be difficult to realize multiple different brightness between 0-350mA as the Dimmable LED driver of 0-350mA, then obviously this LED driver can not satisfy the demands.Visible, because the output of LED driver is worth immutable most, limit the application scenario that LED driver can be suitable for, and there is multiple output current (or output voltage) specification due to LED driver, be therefore also unfavorable for commercial criterion.

And in the utility model embodiment, provide a kind of LED driver, to realize reducing the restriction to the application scenario of LED driver.

Below in conjunction with the accompanying drawing in the utility model embodiment, be clearly and completely described the technical scheme in the utility model embodiment, obviously, described embodiment is only the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those skilled in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.

Refer to Fig. 1, the utility model embodiment provides a kind of embodiment of LED driver 10, and the LED driver 10 of the present embodiment comprises: export initialization circuit 101, at least one can on-off component 102 and the first terminal 103.

Export output voltage values and/or output current value that initialization circuit 101 sets the LED driver 10 of the present embodiment, namely, when exporting circuit parameter variations in initialization circuit 101, the output voltage values of LED driver 10 and/or output current value also can change, that is, the LED driver 10 of the present embodiment comes regulation output magnitude of voltage and/or output current value mainly through exporting initialization circuit 101, and the output voltage values of such as LED driver 10 and/or output current value can have monotonicity relation within the specific limits with the circuit parameter exporting initialization circuit 101.

The first terminal 103 is for reception control signal.In the utility model embodiment, the first terminal 103 refers to the device that can realize being electrically connected, and comprises lead-in wire, port, joint etc.Wherein, the control signal that the first terminal 103 receives is actually can on-off component 102 for controlling at least one, and therefore, the first terminal can the control end of on-off component 102 be connected with at least one.If wherein at least one on-off component can comprise controlled switching device, then the first terminal is connected with the control end of controlled switching device itself; If can on-off component comprise there is auxiliary control circuit can switching device, then the first terminal is connected with the control end of auxiliary control circuit.

At least one on-off component 102 can be in expendable path or off state under the control of control signal that receives at the first terminal 103.In the utility model embodiment, can on-off component refer to due to its physical characteristic, or the physical characteristic of drive circuit included by it, the device of expendable path or off state can be there is.Illustrate below: at least one on-off component 102 can comprise controlled switching device, such as switching tube etc., controlled switching device can be in expendable path or off state under the direct control of control signal.Or, at least one can on-off component 102 can comprise there is auxiliary control circuit can switching device; Auxiliary control circuit is used under the direct control of control signal, change described can the connection status of switching device, to make describedly to be in expendable path or off state by switching device; Wherein can comprise at least one in following device by switching device: switching tube, fusible device (such as fuse) and resistance.Here, whether " connection status " can be can the conduction terminal of switching device and the annexation of other devices, such as can be linked in certain primary Ioops by switching device; Also can be can the control end of switching device and the annexation of other devices, can switching device be now controlled tr tube, auxiliary control circuit be the drive circuit for driving controlled tr tube.Wherein, expendable path or off state refer to, a path or open circuit can only occur on-off component, when being again connected in loop after path or open circuit occur, and can on-off component not controlled and the path occurred before maintaining or off state.

Provide below a kind of at least one can the preferred structure of on-off component 102, as shown in Figure 3, at least one can on-off component 102 comprise: multiple switching tube with drive circuit; Wherein drive circuit is in path or off state for driving switch pipe; Schematically illustrate 5 switching tubes (be metal-oxide-semiconductor in figure 3 with switching tube be example) on the left of Fig. 3, right side shows the drive circuit (driving circuit structure of each switching tube is identical) of wherein any one switching tube.

Each drive circuit comprises the first resistance R1 and the second resistance R2 respectively, first resistance R1 of each drive circuit is connected between the control end of supply voltage VCC and the switching tube belonging to this drive circuit, the second resistance R2 of each drive circuit be connected to and the control end of switching tube belonging to this drive circuit between.

First resistance R1 or the second resistance R2 of each drive circuit are used for, and are damaged under control of the control signal, and are in expendable path or off state after damaging, and are in expendable path or off state to make each switching tube.That is, control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable channel status, is in fact exactly burn short circuit; Or control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable off state, also namely blows road.Such as, the first resistance can make switching tube be in channel status after burning short circuit always, and the second resistance can make switching tube be in off state always, because the state of drive circuit is irrecoverable, the state of switching tube therefore can be made irrecoverable after burning short circuit; Or, after the first resistance blows road, switching tube can be made to be in off state always, after the second resistance blows road, switching tube can be made to be in channel status always, because the state of drive circuit is irrecoverable, the state of switching tube therefore can be made irrecoverable.

At least one can the path of on-off component 102 or off state, association exports the circuit parameter for the output voltage values and/or output current value that set LED driver in initialization circuit 101, is worth most or output current is worth most with the output voltage of the LED driver associating the present embodiment." circuit parameter " of indication in above-mentioned explanation, can refer to and be input to the signal exported in initialization circuit 101, export the signal that initialization circuit 101 exports or the electrical quantity (as the resistance of resistance or the capacitance of electric capacity etc.) exporting device in initialization circuit 101.Known by above-mentioned incidence relation, when at least one can the path of on-off component 102 or off state change time, the foregoing circuit parameter exported in initialization circuit 101 can be changed, thus the output voltage changing LED driver 10 is worth most or output current is worth most.And at least one can the path of on-off component 102 or off state, can by wherein partly or entirely can the path of on-off component or off state changing.

Wherein, output voltage is worth refers to output voltage maximum and/or minimum value most, and output current is worth refers to output current maximum and/or minimum value most.For can not the LED driver of light modulation, output voltage is worth and is worth most with output current be most exactly rated output voltage value and the output-current rating value of LED driver.For the LED driver of tunable optical, such as the output voltage range of adjustable voltage stabilizing LED driver is at 10V-100V, then output voltage maximum is 100V, and minimum value is 10V; And for example the output current scope of adjustable constant current LED driver is adjustable between 20mA-350mA, then output current maximum is 350mA, and minimum value is 20mA.

Known by technique scheme, the LED driver 10 of the present embodiment comprises output initialization circuit 101, at least one can on-off component 102 and the first terminal 103, wherein the first terminal 103 is for reception control signal, this control signal can make at least one on-off component 102 can be in expendable path or off state, and at least one can the path of on-off component 102 or off state, be associated with the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, thus the output voltage of association LED driver 10 is worth most or output current is worth most, therefore the utility model embodiment can the path of on-off component 102 or off state by changing at least one, change to export in initialization circuit 101 and set the output voltage values of LED driver and/or the circuit parameter of output current value, thus the output voltage that can change LED driver 10 is worth most or output current is worth most, achieve output voltage in visible the utility model embodiment to be worth most or output current is worth adjustable LED driver most, decrease the restriction of the application scenario to LED driver, thus make the LED driver of different size can by the LED driver of same specification substitute, be conducive to commercial criterion.

In fact, there is a kind of mode by regulating the resistance of adjustable resistance to change output valve in prior art, but in this mode of prior art, because adjustable resistance will be operated by user, therefore the outside of LED driver encapsulation must be placed in, and adjustable resistance must be electrically connected with the circuit of LED driver inside, therefore this mode can make LED driver encapsulation be difficult to realize water-proof function.And in the utility model embodiment, electronic device is not needed to be arranged on LED driver package outside, and be generally lead-in wire, joint or port for the first terminal receiving outside control signal, such as conventional water joint or anti-water strand, compared to this electronic device of resistance, waterproof technique is very ripe and more easily realize.

Also it is emphasized that, why the utility model embodiment adopts that state is expendable can on-off component, main cause is that the output in order to not need programming in logic can realize LED driver is worth adjustable most, thus without the need to controllers such as single-chip microcomputers, has therefore saved cost.In the utility model embodiment, by the state of on-off component can directly control the circuit parameter exporting initialization circuit, especially by multiple can the state of on-off component different, directly change the circuit parameter exporting initialization circuit different, realize multiple different output and be worth most.In the process, do not need the circuit in LED driver with special responsive control signal, do not need to distinguish control signal yet, can on-off component directly this difference be embodied, avoid LED driver and use the digital control circuits such as single-chip microcomputer, reduce circuit cost.

Wherein especially illustrate, even if LED driver is Dimmable LED driver, and light modulation line and the first terminal multiplexing time, do not need extra controller to distinguish dim signal and control signal in the utility model yet.

First illustrate that LED driver is Dimmable LED driver, now LED driver also comprises light modulation line and light adjusting circuit.Because light modulation line and light adjusting circuit are the conventional electronic component of prior art or circuit, so its annexation of brief description and accordingly working method here: light modulation line is connected with light adjusting circuit, light adjusting circuit is connected with output initialization circuit.Wherein light modulation line is for receiving dim signal and exporting dim signal to light adjusting circuit, and light adjusting circuit is used for changing according to dim signal the circuit parameter exporting initialization circuit.Wherein control signal can be PWM ripple, and dim signal can be direct current signal.

Secondly illustrate light modulation line and the first terminal multiplexing time working condition.The first terminal and light modulation line multiplexing, owing to can on-off component be connected with the first terminal, and the first terminal uses must be connected with the light adjusting circuit in LED driver as light modulation line simultaneously, light adjusting circuit also acts on and exports in initialization circuit, therefore, also act on can in the circuit of on-off component for dim signal.Without dim signal input and when having control signal input, can on-off component responsive control signal, make corresponding on-off action, thus change output and be worth most; And without control signal input and when having dim signal input, due to dim signal also acts on can in on-off component, by can on-off component and light adjusting circuit acting in conjunction export in initialization circuit, thus the basis that is worth most of output after the change realizes light modulation.Therefore, LED driver is not needed to distinguish dim signal and control signal.

In the utility model embodiment, export output voltage values and output current value that initialization circuit can set LED driver.Concrete, export in initialization circuit and there is reference signal, and during work, be in the state of dynamic conditioning always, namely, the output valve (i.e. output voltage values and/or output current value) of current LED driver is compared as sampled value with reference signal, control the power transimission of LED driver main circuit according to comparative result, make the output valve of LED driver be the corresponding value of reference signal; And when changing the circuit parameter exporting initialization circuit, such as change the sampled signal and/or reference signal that export initialization circuit, the output valve of current LED driver will no longer equal the reference signal of the output initialization circuit after changing circuit parameter, and now export the dynamic conditioning that initialization circuit will be taken turns by another, control the power transimission of LED driver main circuit, make the output valve of LED driver be the corresponding value of reference signal.

In the utility model embodiment, at least one can the path of on-off component 102 or off state, association exports the circuit parameter in initialization circuit 101, thus achieve can the path of on-off component 102 or off state by changing at least one, can change this circuit parameter, thus the output changing LED driver 10 is worth most.Stress below by an embodiment, at least one can on-off component 102 and export the concrete interrelational form of one of circuit parameter of initialization circuit.

Refer to Fig. 2, the utility model embodiment provides the another kind of embodiment of LED driver 20, and in the present embodiment, LED driver 20 comprises: export initialization circuit 201, at least one can on-off component 202 and the first terminal 203.

Export output voltage values and/or output current value that initialization circuit 201 sets LED driver 20.

The first terminal 203 is for reception control signal.The control signal that the first terminal 203 receives is actually can on-off component 202 for controlling at least one, and therefore the first terminal can the control end of on-off component 202 be connected with at least one.

At least one on-off component 202 can be in expendable path or off state under the control of control signal that receives at the first terminal 203.The control signal that wherein the first terminal 203 receives can control each respectively can on-off component.

At least one can in on-off component 202 each can on-off component respectively with after corresponding resistant series, be connected to the output of a voltage signal V1 and export between initialization circuit 201, with make at least one can the path of on-off component 202 or off state association voltage signal V1 on the impact of the circuit parameter exported in initialization circuit 201, to be worth most with the output voltage associating LED driver 20 or output current is worth most; Wherein said circuit parameter is for setting output voltage values and/or the output current value of LED driver 20.Here the impact of voltage signal V1 on circuit parameter refers to the variable quantity that voltage signal V1 makes circuit parameter occur.

In the LED driver 20 shown in Fig. 2, because at least one on-off component 202 can be connected to the output of voltage signal V1 and export between initialization circuit 201, thus make when at least one can the path of on-off component 202 or off state change time, voltage signal V1 exports the voltage exporting initialization circuit 201 to and also can change, and therefore can change the circuit parameter exporting initialization circuit 201.

Wherein each can the resistance value of respectively corresponding each resistance of on-off component, also can change to voltage signal V1 and export the magnitude of voltage exporting initialization circuit 201 to, thus changes to export and be worth most.Therefore by arranging the resistance value of each resistance, the adjustment to exporting the multiple different gear be worth most can be realized.Such as, one preferably mode is, each can the resistance value of respectively corresponding each resistance of on-off component equal, therefore by be in path or off state can the number of on-off component different, the adjustment to exporting the multiple different gear be worth most can be realized.Also have one preferably mode be, each can the resistance value equal difference of corresponding respectively each resistance of on-off component increase progressively, now by specific one or multiple resistance value corresponding on-off component can be in path or off state, the adjustment to exporting the multiple different gear be worth most can be realized.

Wherein when LED driver 20 is Dimmable LED driver, voltage signal V1 is the dim signal of LED driver.In fact that is, at least one on-off component 202 can be connected to the output of dim signal and exports between initialization circuit 201.It should be noted that, when regulating the output of LED driver to be worth most, dim signal can input arbitrary value or not input, but does not affect the adjustment be worth most the output of LED driver.This connected mode, achieves while regulation output is worth most, the output valve in linear regulation dimming process.Such as when not regulating the output of LED driver to be worth most, the scope of the output current value of LED driver is at 0-1A, and output current value corresponding to original dim signal P is 0.25A.And can the state of on-off component by changing at least one, make the output current maximum of LED driver be adjusted to 2A, namely the scope of output current value is at 0-2A, and the output current value that dim signal P is now corresponding is (2/1) × 0.25=0.5A.

Wherein when LED driver 20 be can not the LED driver of light modulation time, voltage signal V1 is fixed voltage signal, and its magnitude of voltage remains unchanged.

In the utility model, additionally provide at least one can a kind of preferred structure of on-off component 202, particularly, at least one can on-off component comprise: multiple switching tube with drive circuit, and wherein drive circuit is in path or off state for driving described switching tube.Schematically illustrate 5 switching tubes (be metal-oxide-semiconductor in figure 3 with switching tube be example) on the left of Fig. 3, right side shows the drive circuit (driving circuit structure of each switching tube is identical) of wherein any one switching tube.

Wherein, first conduction terminal of each switching tube is (if the first conduction terminal of 5 metal-oxide-semiconductors in Fig. 3 is the output that (SW1 end, SW2 end, SW3 end, SW4 end, SW5 end) all connects voltage signal V1, second conduction terminal is connected to the same one end exporting initialization circuit 201 after being all connected to same end points (the SOURCE end as in Fig. 3); Each drive circuit comprises the first resistance R1 and the second resistance R2 respectively, first resistance R1 of each drive circuit is connected between the control end of supply voltage VCC and the switching tube belonging to this drive circuit, the second resistance R2 of each drive circuit be connected to and the control end of switching tube belonging to this drive circuit between.It should be noted that, generally, the source electrode of each switching tube is also connected with the control end of this switching tube respectively, is namely connected on the ground.The resistance of the first resistance in Fig. 3 is 20k Ω, the resistance of the second resistance is 100 Ω, be only a kind of example of preferred resistance, in fact the utility model embodiment is to the resistance of the first resistance and the second resistance, and its resistance type (such as adjustable resistance is also non-adjustable resistance etc.) is not all limited.

First resistance R1 or the second resistance R2 of each drive circuit are used for, and are damaged under control of the control signal, and are in expendable path or off state after damaging, and are in expendable path or off state to make each switching tube.That is, control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable channel status, is in fact exactly burn short circuit; Or control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable off state, also namely blows road.

As shown in Figure 3; multiple switching tube with drive circuit can be encapsulated in a chip usually; by corresponding leads ends connection signal; such as, in Fig. 3, SW1 end, SW2 end, SW3 end, SW4 end, SW5 end connect voltage signal V1; SOURCE end connects output initialization circuit; TRIM end connects the first terminal, thus reception control signal.

It should be noted that, the output initialization circuit in the utility model embodiment can adopt any one can change the output voltage values of LED driver and/or the circuit of output current value.At present, the output current of LED driver can be set by inner electric current loop, and output voltage sets by the Voltage loop of inside, and electric current loop herein or Voltage loop can as output initialization circuits of the present utility model.The current reference signal set is had in electric current loop, by the output current sampled signal of sampling circuit samples LED driver, and by comparison circuit, sampled signal and current reference signal are compared, controlled the output current of LED driver by comparative result, thus make output current be the electric current that current reference signal is corresponding.The output voltage of LED driver can be controlled by inner Voltage loop, and the similar operation principle with electric current loop of its control principle, difference is sampling and outputting voltage sampled signal and compares with voltage reference signal.

Therefore, as shown in Figure 4, a kind of alternate configurations exporting initialization circuit 201 comprises sample circuit 2011 and comparison circuit 2012; Sample circuit 2011 is for the output voltage values of LED driver 20 of sampling and/or output current value.The output voltage values that the input input sampling circuit 2011 of comparison circuit 2012 is sampled and/or output current value and reference signal, the output of comparison circuit 2012 is as the output exporting initialization circuit 201.Under the setting exporting initialization circuit 201, the output voltage values of described LED driver 20 or output current value are the ratio of reference signal and oversampling ratio.Concrete, comparison circuit 2012 controls the main circuit switch pipe in LED driver 20, by the change of switching tube duty ratio or frequency, change output current or the output voltage of LED driver, thus make the sampled signal in comparison circuit 2012 (i.e. the signal of sample circuit 2011 output) equal with reference signal, wherein reference signal comprises voltage reference signal and/or current reference signal.

In the present embodiment, export the circuit parameter for the output voltage values and/or output current value that change LED driver in initialization circuit 201, include but not limited to: the sampled signal that sample circuit 2011 exports, reference signal.

If export initialization circuit 201 to comprise sample circuit 2011 and comparison circuit 2012, then can be as shown in Figure 4, at least one can on-off component 202 be connected between the output of voltage signal V1 and the first input end exporting initialization circuit, and wherein first input end is used for the sampled signal of input sampling circuit 2011.Wherein, the path of on-off component 202 or off state can change the sampled signal exported in initialization circuit, thus change the output valve (output current value and/or output voltage values) of LED driver.Now, when at least one can the path of on-off component 202 or off state change time, the input value of comparison circuit 2012 can be changed, thus control output current value and/or the output voltage values of LED driver by comparison circuit 2012.In fact in other implementation, at least one on-off component only can need meet and be connected with the input of comparison circuit and/or output, to make at least one can the path of on-off component or off state, association voltage signal V1 is on the impact of the input of comparison circuit 2012 and/or the magnitude of voltage of output, to associate the impact of voltage signal V1 on the circuit parameter exported in initialization circuit 201, in fact be exactly can the change of state of on-off component by least one, also change with the magnitude of voltage making voltage signal V1 input to comparison circuit thereupon, thus affect reference signal and/or the sampled signal of comparison circuit.Such as in the diagram, at least one can on-off component 202 can also be connected between the output of voltage signal V1 and the second input of comparison circuit, second input and reference signal input, or between the output being connected to voltage signal V1 and the output of comparison circuit.

Known by technique scheme, present embodiments provide a kind of can on-off component with export the concrete connected mode of initialization circuit, thus make the path of on-off component or off state to be associated with the circuit parameter exporting initialization circuit.Each providing in addition can on-off component and the preferred structure exporting initialization circuit.

It should be noted that, the LED driver of the utility model embodiment, the main function realized is that adjustable output is worth most, and the dimming function of the LED driver of this and tunable optical is two kinds of completely independently functions.First, be no matter the LED driver for tunable optical, still can not the LED driver of light modulation, all can be applicable to the utility model embodiment.Secondly, the utility model embodiment, indeed through can the state of on-off component, realizes the adjustment of the circuit structure to LED driver itself, and dimming function does not then relate to can the state change of on-off component.Finally, LED driver in the utility model embodiment, generally when not being in normal work (such as load is in zero load or LED driver does not power on), realize exporting the adjustment be worth most, dimming function then for LED driver be in normally work time, here " normally work " i.e. input voltage in the input voltage range of LED driver nominal, and connect suitable load in the loading range of nominal.Wherein, LED driver when realizing light modulation, because load is constant, therefore along with the change power output of output current is in constantly change, and the LED driver of the utility model embodiment realize adjustment export be worth most time, power output is actually that change is very little even not to change.The following describes in the utility model embodiment adjust export be worth most time, realize power output change the very little a kind of specific implementation means even do not changed.

In the utility model embodiment, export output voltage values and output current value that initialization circuit can set LED driver.Further, at least one can the path of on-off component or the incidence relation of off state and circuit parameter, make at least one can the path of on-off component or off state change time, the output voltage values of LED driver is contrary with the variation tendency of output current value.Such as power output be 100W can not dimming LED driver, after output-current rating value (namely output current is worth most) is adjusted to 10A from 5A, rated output voltage value can be adjusted to 9V from 20V, achieve output voltage simultaneously and be worth most the adjustment be worth most with output current, and LED driver now power output be 90W.Certainly, in other example, also only can realize output voltage and be worth an adjustment be worth most in being worth most with output current most.

Wherein all require that power output is constant under many circumstances, therefore a kind of optimal way is, at least one can the path of on-off component or off state change time, the output voltage values of LED driver and the change multiple of output current value are reciprocal relation, to make the power output of described LED driver constant.That is, at least one can on-off component with export the annexation of initialization circuit, make at least one can the state of on-off component when changing, circuit parameter also changes, and the change that circuit parameter occurs makes the output voltage values of LED driver become reciprocal relation with the change multiple of output current value, such as output voltage values becomes 2 times of original output voltage values, output current value becomes 0.5 times of original output current value, thus make the product of output voltage values and output current value constant, therefore power output is constant.

Wherein set output voltage values and the output current value of LED driver owing to exporting initialization circuit, therefore can be as shown in Figure 5 simultaneously, exports initialization circuit and comprise voltage setting circuit 401 and current setting circuit 402; Wherein voltage setting circuit 401 sets the output voltage values of LED driver, and current setting circuit 402 sets the output current value of LED driver.Voltage setting circuit 401 and current setting circuit 402 can adopt any one circuit for the output voltage values and output current value that control LED driver of prior art.

And at least one can the path of on-off component or off state, associates the circuit parameter in voltage setting circuit 401 and the circuit parameter in current setting circuit 402 simultaneously; And this incidence relation makes at least one can the path of on-off component or off state when changing, the change of the circuit parameter in voltage setting circuit 401 is corresponding with the change of the circuit parameter in current setting circuit 402, contrary with the variation tendency of the output current value of the output voltage values with LED driver that make LED driver, preferably, change multiple is reciprocal relation, thus to make the power output of LED driver constant.Wherein 401 circuit parameters of voltage setting circuit are for setting the output voltage values of LED driver, and the circuit parameter of current setting circuit 402 is for setting the output current value of LED driver.

Such as shown in Fig. 5, voltage setting circuit 401 can comprise voltage sampling circuit 4011 and voltage comparator circuit 4012, and current setting circuit 402 can comprise current sampling circuit 4021 and current comparison circuit 4022.Voltage sampling circuit 4011 is for the output voltage values of LED driver of sampling, the sampled value of the input input voltage sample circuit 4011 of voltage comparator circuit 4012 and reference voltage value, the output of voltage comparator circuit 4012 is as the output of voltage setting circuit 401, the main circuit of LED driver is controlled, with the magnitude of voltage making the output voltage values of LED driver equal reference voltage value setting by this output.Current sampling circuit 4021 is for the output current value of LED driver of sampling, the sampled value of the input input current sample circuit 4021 of current comparison circuit 4022 and reference current value, current comparison circuit 4022 output is as the output of current setting circuit 402, the main circuit of LED driver is controlled, with the current value making the output current value of LED driver equal reference current value setting by this output.

At least one each in on-off component on-off component can be divided into two device groups respectively: can break-make group 403 and can break-make group 404; Wherein can break-make group 403 be connected between the output of voltage signal V1 and voltage setting circuit 401, can break-make group 404 be connected between the output of voltage signal V2 and current setting circuit 402.Wherein can realize output current value is in the following way reciprocal relation with the change multiple of output voltage values: can break-make group 403 with can break-make group 404 comprise respectively can on-off component number identical, two can break-make group can on-off component one_to_one corresponding, and corresponding two can on-off component control end be connected, namely corresponding two on-off component can remain identical state, such as be in expendable off state under control of the control signal simultaneously.Therefore make at least one can the path of on-off component or off state when changing, the change of the circuit parameter in voltage setting circuit 401 is corresponding with the change of the circuit parameter in current setting circuit 402, is reciprocal relation with the change multiple of the output current value of the output voltage values and LED driver that make LED driver.

Certainly except above this mode, the change multiple that other modes can also be adopted to realize output current value and output voltage values is reciprocal relation.Such as can adopt same can break-make group (comprise at least one can on-off component), this break-make group can change the circuit parameter of output current initialization circuit and voltage setting circuit respectively, such as break-make group can export different conditioning signals respectively to these two initialization circuits, to realize output current and output voltage multiple is reciprocal relation.

In the utility model embodiment, at least one can on-off component comprise one or more can on-off component, wherein control signal can control respectively each can the path of on-off component or off state.Therefore can the number of on-off component according at least one, corresponding different output is worth regulative mode most respectively.

Particularly, at least one can the number of on-off component when being, this can on-off component in the front and back being in expendable path or off state, the circuit parameter of corresponding output initialization circuit is different.Thus make this on-off component can be in expendable path or off state by control signal, can realize exporting the adjustment be worth most.Such as shown in Fig. 6, when can on-off component 601 conducting time, voltage signal V1 inputs to the input of comparison circuit, when can on-off component 601 be in expendable off state time, voltage signal V1 no longer affects comparison circuit.At least one can the number of on-off component when being multiple (namely at least two), then multiple can on-off component by the circuit parameter of output initialization circuit corresponding to different states, thus corresponding different output is worth most.Such as shown in Fig. 7, at least one can on-off component comprise can on-off component 701 and can on-off component 702, can the different conditions of on-off component by these two, can produce the change of 4 kinds of varying levels to the input of comparison circuit 2012, therefore corresponding 4 kinds of different outputs are worth most respectively.Now after the first terminal receives control signal, can control on-off component can be in expendable path or off state accordingly, thus obtain the circuit parameter of corresponding output initialization circuit, if obviously only make part on-off component can be in expendable path or open circuit during each adjustment, then can realize exporting the repeatedly adjustment be worth most.

In the utility model embodiment, at least one on-off component under control of the control signal, can be in expendable path or off state, and its specific implementation can have multiple, be not limited in the utility model embodiment, optional implementation be only described below.

Can on-off component comprise controlled switching device or there is auxiliary control circuit can switching device.

Controlled switching device is used under the direct control of control signal, and never access state or regular path state change into abnormal channel status, to be in expendable path or off state.Such as a certain controlled switching device is in off-state, therefore non-access state is in, namely be not linked in any loop, and control signal can directly control controlled switching device conducting thus be linked in loop, and the electric current in this loop exceedes the running current scope of controlled switching device, controlled switching device is therefore made to be in abnormal channel status.If wherein controlled switching device comprises switching tube, control signal is the drive singal of switching tube.

Can at least have two kinds of situations switching device for what have an auxiliary control circuit, the first situation expendable state can occur changes by switching device; The second situation is that the change of expendable state occurs auxiliary control circuit.Illustrate respectively below.

The first situation: auxiliary control circuit be used under the direct control of control signal, make can switching device never access state or regular path state change into abnormal channel status, to make to be in expendable path or off state by switching device.

The second situation: can switching device be switching tube, auxiliary control circuit be the drive circuit of switching tube, is in path or off state for driving switch pipe; Drive circuit is used under the direct control of control signal, never access state or regular path state change into abnormal channel status, thus this drive circuit is in expendable state, be in expendable path or off state with further driving switch pipe.

Wherein abnormal channel status can make the device being in this state be damaged.That is, controlled switching device, auxiliary control circuit and can switching device when being in abnormal channel status, generally can be damaged.Such as, switching tube is (linear conducting or saturation conduction) when conducting, if the electric current on loop, place is excessive when causing exceeding running current scope, then can be damaged, and the switching tube after damaging can be in expendable channel status or off state.When the electric current on loop, fuse place is excessive cause exceeding running current scope time, can fuse, the fuse after fusing is equivalent to be in expendable off state.

Corresponding with the embodiment of any one LED driver that the utility model provides, the utility model embodiment still provides a kind of method that output changing LED driver is worth most.Specifically described below.

Refer to Fig. 8, a kind of embodiment of the method that the output that the utility model additionally provides change LED driver is worth most.LED driver 10 in the present embodiment as shown in Figure 1, comprising: export initialization circuit 101, at least one can on-off component 102 and the first terminal 103.Export output voltage values and/or output current value that initialization circuit 101 sets LED driver 10

The method of the present embodiment comprises:

S801: the first terminal 103 reception control signal.In the utility model embodiment, the first terminal 103 refers to the device that can realize being electrically connected, and comprises lead-in wire, port, joint etc.Wherein, the control signal that the first terminal 103 receives is actually can on-off component 102 for controlling at least one, and therefore, the first terminal can the control end of on-off component 102 be connected with at least one.

S802: at least one can be in expendable path or off state under the control of control signal that receives at the first terminal 103 of on-off component 102.In the utility model embodiment, at least one on-off component 102 can comprise controlled switching device, such as switching tubes etc., now this step can comprise: controlled switching device is in expendable path or off state under the direct control of control signal.Or, at least one can on-off component 102 can comprise there is auxiliary control circuit can switching device; Now this step can comprise: auxiliary control circuit is under the direct control of control signal, and changing can the connection status of switching device, to make describedly to be in expendable path or off state by switching device; Wherein can comprise at least one in following device by switching device: switching tube, fusible device (such as fuse) and resistance.

Each drive circuit comprises the first resistance R1 and the second resistance R2 respectively, first resistance R1 of each drive circuit is connected between the control end of supply voltage VCC and the switching tube belonging to this drive circuit, the second resistance R2 of each drive circuit be connected to and the control end of switching tube belonging to this drive circuit between.Now this step specifically comprises: the first resistance R1 or the second resistance R2 of each drive circuit are damaged under control of the control signal, and be in expendable path or off state after damaging, be in expendable path or off state to make each switching tube.That is, control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable channel status, is in fact exactly burn short circuit; Or control signal can make the first resistance R1 in each drive circuit or the second resistance R2 be damaged and be in expendable off state, also namely blows road.

S803: at least one can after the path of on-off component 102 or off state change, change the circuit parameter exported for the output voltage values and/or output current value that set LED driver 10 in initialization circuit 101, to be worth most with the output voltage of the LED driver changing the present embodiment or output current is worth most.Wherein at least one can the path of on-off component 102 or off state, can by wherein partly or entirely can the path of on-off component or off state changing, that is control signal can make part the path of on-off component or off state change, and also can make all can the path of on-off component or off state to change.

Wherein, output voltage is worth refers to output voltage maximum and/or minimum value most, and output current is worth refers to output current maximum and/or minimum value most.

It should be noted that, the LED driver adopted in embodiment of the method for the present utility model, any one embodiment of the LED driver that can provide for the utility model.

In the utility model embodiment, when LED driver is Dimmable LED driver, LED driver also comprises light modulation line and light adjusting circuit.Light modulation line is connected with light adjusting circuit, and light adjusting circuit is connected with output initialization circuit, and the first terminal 103 is multiplexing with light modulation line.Wherein light modulation line is for receiving dim signal and exporting dim signal to light adjusting circuit, and light adjusting circuit is used for changing according to dim signal the circuit parameter exporting initialization circuit.Wherein control signal can be PWM ripple, and dim signal can be direct current signal.

In the utility model embodiment, can the path of on-off component 102 or off state by changing at least one, this circuit parameter can be changed, thus the output changing LED driver 10 is worth most.Stress below by an embodiment, at least one can on-off component 102 and export the concrete interrelational form of one of circuit parameter of initialization circuit.

Refer to Fig. 9, the another kind of embodiment of the method that the output that the utility model additionally provides change LED driver is worth most.LED driver 20 in the present embodiment as shown in Figure 2, comprising: export initialization circuit 201, at least one can on-off component 202 and the first terminal 203.Export output voltage values and/or output current value that initialization circuit 201 sets LED driver 20.At least one can in on-off component 202 each can on-off component respectively with after corresponding resistant series, be connected to the output of a voltage signal V1 and export between initialization circuit 201.When LED driver 20 is Dimmable LED driver, voltage signal V1 is the dim signal of LED driver.When LED driver 20 be can not the LED driver of light modulation time, voltage signal V1 is fixed voltage signal, and its magnitude of voltage remains unchanged.

S901: the first terminal 203 reception control signal.The control signal that the first terminal 203 receives is actually can on-off component 202 for controlling at least one, and therefore the first terminal can the control end of on-off component 202 be connected with at least one.

S902: at least one can be in expendable path or off state under the control of control signal that receives at the first terminal 203 of on-off component 202.The control signal that wherein the first terminal 203 receives can control each respectively can on-off component.

S903: at least one can after the path of on-off component 202 or off state change, change the impact of voltage signal V1 on the circuit parameter exported in initialization circuit 201, to change the circuit parameter exported in initialization circuit 201, thus to be worth most with the output voltage changing LED driver 20 or output current is worth most.Wherein said circuit parameter is for setting output voltage values and/or the output current value of LED driver.Here the impact of voltage signal V1 on circuit parameter refers to the variable quantity that voltage signal V1 makes circuit parameter occur.

Wherein each can the resistance value of respectively corresponding each resistance of on-off component, also can change to voltage signal V1 and export the magnitude of voltage exporting initialization circuit 201 to, thus changes to export and be worth most.Therefore by arranging the resistance value of each resistance, the adjustment to exporting the multiple different gear be worth most can be realized.Such as, preferably mode is, each can the resistance value of respectively corresponding each resistance of on-off component equal, or each can the resistance value equal difference of corresponding respectively each resistance of on-off component increase progressively.

Wherein, first conduction terminal of each switching tube is (if the first conduction terminal of 5 metal-oxide-semiconductors in Fig. 3 is the output that (SW1 end, SW2 end, SW3 end, SW4 end, SW5 end) all connects voltage signal V1, second conduction terminal is connected to the same one end exporting initialization circuit 201 after being all connected to same end points (the SOURCE end as in Fig. 3); Each drive circuit comprises the first resistance R1 and the second resistance R2 respectively, first resistance R1 of each drive circuit is connected between the control end of supply voltage VCC and the switching tube belonging to this drive circuit, the second resistance R2 of each drive circuit be connected to and the control end of switching tube belonging to this drive circuit between.

Step S902 is specially: the first resistance R1 or the second resistance R2 of each drive circuit are damaged under control of the control signal, and be in expendable path or off state after damaging, be in expendable path or off state to make each switching tube.

As shown in Figure 4, a kind of alternate configurations exporting initialization circuit 201 comprises sample circuit 2011 and comparison circuit 2012; Sample circuit 2011 is for the output voltage values of LED driver 20 of sampling and/or output current value.The output voltage values that the input input sampling circuit 2011 of comparison circuit 2012 is sampled and/or output current value and reference signal, the output of comparison circuit 2012 is as the output exporting initialization circuit 201.Wherein reference signal comprises voltage reference signal and/or current reference signal, corresponding with the sampled value of sample circuit 2011.

If export initialization circuit 201 to comprise sample circuit 2011 and comparison circuit 2012, then can be as shown in Figure 4, at least one can on-off component 202 be connected between the output of voltage signal V1 and the first input end exporting initialization circuit, and wherein first input end is used for the sampled value of input sampling circuit 2011.Now, when at least one can the path of on-off component 202 or off state change time, the input value of comparison circuit 2012 can be changed, thus change the output valve of LED driver by comparison circuit 2012.In other implementation, at least one on-off component only can need meet and be connected with the input of comparison circuit and/or output.Such as in the diagram, at least one can on-off component 202 can also be connected between the output of voltage signal V1 and the second input of comparison circuit, or between the output being connected to voltage signal V1 and the output of comparison circuit.

At least one in step S903 after the path of on-off component 202 or off state change, can change the impact of voltage signal V1 on the circuit parameter exported in initialization circuit 201, comprising:

At least one can after the path of on-off component 202 or off state change, change the voltage signal V1 impact on the input of comparison circuit 2012 and/or the magnitude of voltage of output, to change the impact of voltage signal V1 on the described circuit parameter exported in initialization circuit 201.

Known by technique scheme, present embodiments provide a kind of can on-off component with export the concrete connected mode of initialization circuit.Also each providing can on-off component and the preferred structure exporting initialization circuit.

The following describes in the utility model embodiment adjust export be worth most time, realize power output change the very little a kind of specific implementation means even do not changed.

In the utility model embodiment, export output voltage values and output current value that initialization circuit can set LED driver.At least one can after the path of on-off component or off state change, and changes the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, can comprise:

At least one can after the path of on-off component or off state change, change the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, contrary with the variation tendency of the output voltage values and output current value that make LED driver.Wherein a kind of optimal way is, at least one can after the path of on-off component or off state change, and the output voltage values of LED driver and the change multiple of output current value are reciprocal relation, to make the power output of LED driver constant.

Wherein set output voltage values and the output current value of LED driver owing to exporting initialization circuit, therefore can be as shown in Figure 5 simultaneously, exports initialization circuit and comprise voltage setting circuit 401 and current setting circuit 402; Wherein voltage setting circuit 401 sets the output voltage values of LED driver, and current setting circuit 402 sets the output current value of LED driver.

At least one can after the path of on-off component or off state change, change the circuit parameter exported for the output voltage values and/or output current value that set LED driver in initialization circuit, contrary with the variation tendency of the output voltage values and output current value that make LED driver, comprising:

At least one can after the path of on-off component or off state change, change the circuit parameter in voltage setting circuit and the circuit parameter in current setting circuit, and the change of the circuit parameter in voltage setting circuit is corresponding with the change of the circuit parameter in current setting circuit, contrary with the variation tendency of the output voltage values and output current value that make LED driver.Preferably, change multiple is reciprocal relation, thus to make the power output of LED driver constant.Wherein the circuit parameter of voltage setting circuit 401 is for setting the output voltage values of LED driver, and the circuit parameter of current setting circuit 402 is for setting the output current value of LED driver.Such as shown in Fig. 5, voltage setting circuit 401 can comprise voltage sampling circuit 4011 and voltage comparator circuit 4012, and current setting circuit 402 can comprise current sampling circuit 4021 and current comparison circuit 4022.Voltage sampling circuit 4011 is for the output voltage values of LED driver of sampling, the sampled value of the input input voltage sample circuit 4011 of voltage comparator circuit 4012 and reference voltage value, the output of voltage comparator circuit 4012 is as the output of voltage setting circuit 401, the main circuit of LED driver is controlled by this output,, with the magnitude of voltage making the output voltage values of LED driver equal reference voltage value setting.Current sampling circuit 4021 is for the output current value of LED driver of sampling, the sampled value of the input input current sample circuit 4021 of current comparison circuit 4022 and reference current value, current comparison circuit 4022 output is as the output of current setting circuit 402, the main circuit of LED driver is controlled, with the current value making the output current value of LED driver equal reference current value setting by this output.

In the utility model embodiment, at least one can on-off component under control of the control signal, be in expendable path or off state, its specific implementation can have multiple, be not limited in the utility model embodiment, optional implementation be only described below.

Controlled switching device is in expendable path under the direct control of control signal or off state comprises: controlled switching device is under the direct control of control signal, never access state or regular path state change into abnormal channel status, to be in expendable path or off state.

The first situation: auxiliary control circuit is under the direct control of control signal, change can the connection status of switching device, to make to be in expendable path or off state by switching device, comprise: auxiliary control circuit is under the direct control of control signal, make can switching device never access state or regular path state change into abnormal channel status, to make to be in expendable path or off state by switching device.

The second situation: can switching device be switching tube, auxiliary control circuit be the drive circuit of switching tube, is in path or off state for driving switch pipe; Auxiliary control circuit is under the direct control of control signal, change can the connection status of switching device, to make to be in expendable path or off state by switching device, comprise: drive circuit is under the direct control of control signal, never access state or regular path state change into abnormal channel status, thus this drive circuit is in expendable state, be in expendable path or off state with further driving switch pipe.

Wherein abnormal channel status can make the device being in this state be damaged.That is, controlled switching device, auxiliary control circuit and can switching device when being in abnormal channel status, generally can be damaged.

The above is only preferred implementation of the present utility model; it should be pointed out that for those skilled in the art, under the prerequisite not departing from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection range of the present utility model.

Claims

1. a LED driver, is characterized in that, comprising: export initialization circuit, at least one can on-off component and the first terminal; Described output initialization circuit sets output voltage values and/or the output current value of described LED driver;

Described the first terminal is used for reception control signal;

2. LED driver according to claim 1, is characterized in that, described output initialization circuit sets output voltage values and the output current value of described LED driver;

Described at least one can the path of on-off component or the incidence relation of off state and described circuit parameter, make described at least one can the path of on-off component or off state change time, the output voltage values of described LED driver is contrary with the variation tendency of output current value.

3. LED driver according to claim 2, is characterized in that, described output initialization circuit comprises: voltage setting circuit and current setting circuit; Described voltage setting circuit sets the output voltage values of described LED driver, and described current setting circuit sets the output current value of described LED driver;

Described at least one can the path of on-off component or off state, associate the circuit parameter in described voltage setting circuit and the circuit parameter in described current setting circuit simultaneously, and this incidence relation make described at least one can the path of on-off component or off state when changing, the change of the circuit parameter in described voltage setting circuit is corresponding with the change of the circuit parameter in described current setting circuit, to make the output voltage values of described LED driver contrary with the variation tendency of the output current value of described LED driver;

The circuit parameter of wherein said voltage setting circuit is for setting the output voltage values of described LED driver, and the circuit parameter of described current setting circuit is for setting the output current value of described LED driver.

4. LED driver according to claim 1, it is characterized in that, described at least one can in on-off component each can on-off component respectively with after corresponding resistant series, be connected between the output of a voltage signal and described output initialization circuit, with make described at least one the path of on-off component or off state can associate the impact of described voltage signal on circuit parameter described in described output initialization circuit;

When described LED driver is Dimmable LED driver, described voltage signal is the dim signal of described LED driver;

When described LED driver be can not the LED driver of light modulation time, described voltage signal is fixed voltage signal.

5. LED driver according to claim 4, is characterized in that, described each can the resistance value of respectively corresponding each resistance of on-off component equal, or equal difference increases progressively.

6. LED driver according to claim 4, is characterized in that, described at least one can on-off component comprise: multiple switching tube with drive circuit; Described drive circuit is in path or off state for driving described switching tube; First conduction terminal of switching tube described in each all connects the output of described voltage signal, and the second conduction terminal all connects same one end of described output initialization circuit; Drive circuit described in each comprises the first resistance and the second resistance respectively, first resistance of drive circuit described in each is connected between the control end of supply voltage and the switching tube belonging to this drive circuit, the second resistance of drive circuit described in each be connected to and the control end of switching tube belonging to this drive circuit between;

First resistance or second resistance of drive circuit described in each are used for, be damaged under the control of said control signal, and be in expendable path or off state after damaging, be in expendable path or off state to make switching tube described in each.

7. LED driver according to claim 4, is characterized in that, described output initialization circuit comprises comparison circuit and sample circuit;

Described sample circuit is for the output voltage values of described LED driver of sampling and/or output current value;

The input of described comparison circuit inputs the output voltage values of described sampling circuit samples and/or output current value and reference signal, and the output of described comparison circuit is as the output of described output initialization circuit; Described at least one can the input of on-off component and described comparison circuit and/or output be connected, with make described at least one can the path of on-off component or off state, associate the impact of described voltage signal on the input of described comparison circuit and/or the magnitude of voltage of output, to associate the impact of described voltage signal on circuit parameter described in described output initialization circuit.

8. LED driver according to claim 1, is characterized in that, described at least one can on-off component comprise: controlled switching device or there is auxiliary control circuit can switching device;

Described controlled switching device is used for being in expendable path or off state under the direct control of described control signal;

Described auxiliary control circuit is used under the direct control of described control signal, change described can the connection status of switching device, to make describedly to be in expendable path or off state by switching device.

9. LED driver according to claim 8, is characterized in that,

Described controlled switching device is used under the direct control of described control signal, and never access state or regular path state change into abnormal channel status, to be in expendable path or off state.

10. LED driver according to claim 8, is characterized in that,

Described auxiliary control circuit is used under the direct control of described control signal, make described can switching device never access state or regular path state change into abnormal channel status, to make describedly to be in expendable path or off state by switching device;

Or,

Described can switching device be switching tube, and described auxiliary control circuit is the drive circuit of described switching tube, is in path or off state for driving described switching tube; Described drive circuit is used under the direct control of described control signal, and never access state or regular path state change into abnormal channel status, are in expendable path or off state to drive described switching tube.

11. LED drivers according to claim 9 or 10, it is characterized in that, described abnormal channel status can make the device being in this state be damaged.

12. LED drivers according to claim 8, is characterized in that,

Described controlled switching device comprises: switching tube;

Describedly can comprise at least one in following device by switching device: switching tube, fusible device and resistance.

13. LED drivers according to claim 8, is characterized in that, described at least one can on-off component comprise: multiple switching tube with drive circuit; Described drive circuit is in path or off state for driving described switching tube; Drive circuit described in each comprises the first resistance and the second resistance respectively, first resistance of drive circuit described in each is connected between the control end of supply voltage and the switching tube belonging to this drive circuit, the second resistance of drive circuit described in each be connected to and the control end of switching tube belonging to this drive circuit between;

First resistance or second resistance of drive circuit described in each are used for, be damaged under the control of said control signal, and be in expendable channel status or short-circuit condition after damaging, be in expendable path or off state to make switching tube described in each.

14. LED drivers according to claim 1, is characterized in that,

Described LED driver is Dimmable LED driver; Described LED driver also comprises light modulation line and light adjusting circuit;

Described light modulation line is connected with described light adjusting circuit, and described light adjusting circuit is connected with described output initialization circuit;

Described the first terminal and described light modulation line multiplexing.