CN104113957A - Self-excited oscillation driving circuit - Google Patents
Self-excited oscillation driving circuit Download PDFInfo
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- CN104113957A CN104113957A CN201310140843.7A CN201310140843A CN104113957A CN 104113957 A CN104113957 A CN 104113957A CN 201310140843 A CN201310140843 A CN 201310140843A CN 104113957 A CN104113957 A CN 104113957A
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- oscillation drive
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Abstract
The invention discloses a self-excited oscillation driving circuit which comprises a filtering device, a driving device, a switching device, a sampling device connected with the switching device, and a transformer. The transformer at least comprises a self-excited driving winding. The driving device controls on/off of the switching device. The driving device, the self-excited driving winding, the switching device and the sampling device form a loop. The self-excited oscillation driving circuit is characterized in that the self-excited oscillation driving circuit further comprises a current control device connected into the loop formed by the driving device, the self-excited driving winding, the switching device and the sampling device to further control the switching device.
Description
[technical field]
The present invention relates to a kind of drive circuit, especially refer to a kind of drive circuit of light-emitting diode.
[background technology]
Be accompanied by the extensive use of light-emitting diode (LED) technology and product, the demand of supporting LED driving power is also growing with it, in order to reduce design and the production cost of LED driving power, thus the price of reduction LED light fixture, and self-maintained circuit also more and more comes into one's own.As shown in Figure 1, a kind of non-isolated buck circuit type self-oscillation drive circuit 200 comprises driving power 201, fuse F2, rectifier bridge 202, filter 203, starting drive 204, drive unit 205, transformer 206, switching device 207 and sampling apparatus 208.Non-isolated buck circuit type self-oscillation drive circuit 200 is for driving LED load.Transformer 206 has self-excitation and drives winding 209.Circuit shown in Fig. 1 and Fig. 2 is all a kind of topological structure of self-oscillation drive circuit.
Drive cut-off, amplification and the saturation conduction of winding and switching device to realize circuit self-oscillation work by self-excitation, in circuit, inductance or transformer are operated in critical conduction mode, operating frequency can change with input voltage, load (being LED), and all circuit are all without extra control chip and the comparatively expensive field effect transistor of price.Although but self-maintained circuit cost of the prior art is low, but owing to there is no the closed loop feedback of output current in self-maintained circuit, and in self-maintained circuit, do not have the inner such high precision electro pressure reference signal of similar integrated control chip, the control of open loop to make output current in the time of input voltage variation and output loading variation, produce variation greatly yet yet.From actual test result, a employing is the product of reduction voltage circuit formula self-oscillation drive circuit as shown in Figure 2, and in the situation that input voltage changes positive and negative 20%, output current variation reaches positive 17% and negative 26%; And in the situation that output voltage changes positive and negative 13%, output current changes positive and negative 8%, so large output current scope variation can cause the also corresponding generation variation greatly of light output of LED light fixture, affect the practical effect of light fixture, and also can have a certain impact to light fixture heat dissipation design and LED lamp pearl life-span.
Therefore,, in order to overcome above-mentioned defect, be necessary to provide a kind of circuit of improved raising self-oscillation drive circuit constant current accuracy.
[summary of the invention]
The object of the present invention is to provide a kind of self-oscillation drive circuit with higher constant current accuracy.
To achieve these goals, the present invention adopts following technical scheme: a kind of self-oscillation drive circuit, comprise filter, drive unit, switching device, the sampling apparatus being connected with described switching device, and transformer, described transformer at least comprises that a self-excitation drives winding, the turn-on and turn-off of switching device described in described drive unit control, described drive unit, self-excitation drives winding, switching device and sampling apparatus form a loop, it is characterized in that: described self-oscillation drive circuit also comprises and is connected in described drive unit, self-excitation drives winding, current control device between the loop that switching device and sampling apparatus form is further to control described switching device.
Compared to prior art, self-oscillation drive circuit of the present invention has following advantage: the variation of output current is less, and constant current accuracy is higher.
[brief description of the drawings]
Fig. 1 is the circuit diagram of non-isolated buck circuit type self-oscillation drive circuit in prior art.
Fig. 2 is the structured flowchart of self-oscillation drive circuit of the present invention.
Fig. 3 is the circuit diagram in the present invention without the isolation inverse-excitation type self-excitation oscillation drive circuit of current control device.
Fig. 4 is the circuit diagram of the first execution mode of the current control device of self-oscillation drive circuit of the present invention.
Fig. 5 is the circuit diagram of the second execution mode of the current control device of self-oscillation drive circuit of the present invention.
Fig. 6 is the circuit diagram of the current control device of the first execution mode with voltage signal introducing device of self-oscillation drive circuit of the present invention.
Fig. 7 is the circuit diagram of the current control device of the second execution mode with voltage signal introducing device of self-oscillation drive circuit of the present invention.
Fig. 8 is the circuit diagram of the first preferred embodiment of self-oscillation drive circuit of the present invention.
Fig. 9 is the circuit diagram of the second preferred embodiment of self-oscillation drive circuit of the present invention.
Figure 10 is the current waveform of the collector electrode of switching device in first, second kind of preferred embodiment of self-oscillation drive circuit of the present invention.
[embodiment]
Please refer to shown in Fig. 2, self-oscillation drive circuit 1 of the present invention comprises the filter 10, drive unit 20, switching device Q1 and the transformer 30 that connect input voltage V1.The output current of self-oscillation drive circuit 1 is used for driving load LED to light LED.Transformer 30 at least comprises that a self-excitation drives winding L 2.Drive unit 20 is for controlling the device Q1 turn-on and turn-off of opening the light, thereby drives cut-off, amplification and the conducting of winding L 2, switching device Q1 to realize circuit self-oscillation work by self-excitation.Switch element Q1 and self-excitation drive between winding L 2 and are connected a sampling apparatus Rs, so that cut-off, the conducting of sampled signal control switch element Q1 to be provided.
Drive unit 10, self-excitation drive winding L 2, switching device Q1 and sampling apparatus Rs to form a loop.Self-oscillation drive circuit 1 also comprises the current control device 40 between the loop forming at drive unit 10, self-excitation driving winding L 2, switching device Q1 and sampling apparatus Rs.
Except self-oscillation drive circuit of the prior art, self-oscillation drive circuit of the present invention can also be other forms, and as shown in Figure 3, self-oscillation drive circuit of the present invention can also be a kind of isolation inverse-excitation type self-excitation oscillation drive circuit 100.This isolation inverse-excitation type self-excitation oscillation drive circuit 100 comprises driving power 101, fuse F1, rectifier bridge 102, filter 103, starting drive 104, drive unit 105, transformer 106, switching device 107 and sampling apparatus 108.Isolation inverse-excitation type self-excitation oscillation drive circuit 100 is for driving LED load.Transformer 106 has self-excitation and drives winding 109.In other embodiment, self-oscillation drive circuit 100 can also be non-isolated buck circuit type self-oscillation drive circuit or other forms.Current control device 40 of the present invention is applicable to various self-oscillation drive circuits, and endlessly the embodiment in specification is limited.
Please refer to shown in Fig. 4, in the first execution mode of the present invention, the voltage controlled element 41 that current control device 40a comprises switch element Q2 and is connected with switch element Q2.One end connecting switch Q1 and the drive unit of switch element Q2, the other end of switch element Q2 connects voltage controlled element 41; One end connecting valve element Q2 of voltage controlled element 41, the other end connects between sampling apparatus Rs and switching device Q1.Due to the variation of input voltage, the ON time of switching device Q1 increases, and the current peak of switching device Q1 is increased.In the time that the current peak of switching device Q1 increases to certain value, switch element Q2 conducting.Because the conducting of switching device Q1 needs enough pressure drops as condition, when switch element Q2 conducting is set, on switching device Q1, do not there is enough pressure drops, thereby switching device Q1 does not reach turn-on condition, turn-off.Can not continue to increase by the electric current of switching device Q1 like this, the output current of self-oscillation drive circuit 1 can not continue to increase and change.Like this, in the time that input voltage variation causes exceeding certain value through the electric current of switching device Q1, switch element Q2 conducting, switching device Q1 turn-offs, make the output voltage of self-maintained circuit 1 can not increase variation along with the increase of the variation of input voltage, thereby control the excursion of output current, make that load LED's is luminous more stable.Voltage controlled element 41 is wherein for the voltage of by-pass cock element Q2 one end, thereby the time of control switch element Q2 conducting, set certain condition, while making input voltage rise to certain numerical value, a terminal voltage of switch element Q2 just reaches the turn-on condition of switch element Q2.Voltage controlled element 41 can be diode, resistance, voltage-stabiliser tube or their combination.
Please refer to shown in Fig. 5, in the second execution mode of the present invention, current control device 40b comprises stable-pressure device Z, one end connecting drive device 20 of stable-pressure device Z and switching device Q1, and the other end connects one end that sampling apparatus Rs is not connected with drive unit 20.The conducting of switching device Q1 needs two ends to have enough pressure drops.A terminal voltage of switching device Q1 remains identical with the voltage of stable-pressure device Z, and therefore, in the time that input voltage changes the electric current increase that makes switching device Q1, the voltage Vrs of sampling apparatus Rs also increases.In the time that voltage Vrs rises to a certain degree, due to the effect of stable-pressure device Z, the two ends of switching device Q1 have not had enough pressure drops, thereby switching device Q1 turn-offs, the voltage Vrs of sampling apparatus Rs can not continue to increase again, makes output current can excursion too not large.Switching device Q1 can be triode, and stable-pressure device Z is current limliting voltage-stabiliser tube.In the time adopting the voltage-stabiliser tube of negative temperature characteristic, stable-pressure device Z can also be used to offset the base stage of switching device Q1 and the negative temperature characteristic of emitter for triode.Under normal circumstances, stable-pressure device Z adopts voltage stabilizing didoe.
Further, please refer to shown in Fig. 6 to Fig. 7, when constant current accuracy being had while further requiring, current control device 40 also comprises a voltage signal introducing device 42 or 43.The corresponding the first current control device 40a of the first voltage signal introducing device 42.The corresponding the second current control device 40b of the second voltage signal introducing device 43.Voltage signal introducing device 42,43 one end drive winding L 2 to be connected with self-excitation, and the other end is connected with sampling apparatus Rs.According to circuit characteristic, the weighting sum of the voltage at voltage signal introducing device 42,43 two ends is set points, and the weighting sum of voltage Va and voltage Vrs is set point.Therefore when the variation of input voltage makes after the electric current of switching device Q1 increases to certain value, the variation meeting of the voltage Vrs of sampling apparatus Rs is reverse with the variation of input and output voltage difference.Therefore in the time that the input voltage variation of self-oscillation drive circuit exceedes certain limit, its output current can not increase and change because the variation of input voltage increases, thereby has reduced the excursion of output current, makes output current more stable, and constant current accuracy is higher.
Please refer to shown in Fig. 6, be directed to the first current control device 40 of the first execution mode, voltage signal introducing device 42 comprises an impedance component 421 and a resistive element Rb.Impedance component 421 can be electric capacity, resistance or their combination.One end of impedance component 421 connects self-excitation and drives winding L 2, other end contact resistance element Rb; Resistive element Rb one end connects impedance component 421, and the other end connects between sampling apparatus Rs and switching device Q1.
Please refer to shown in Fig. 7, be directed to the second current control device 41 of the second execution mode, voltage signal introducing device 43 is a single element.Voltage signal introducing device 43 can be diode, resistance or capacity cell or their combination.
Concrete, please refer to shown in Fig. 8, in the present invention's the first preferred embodiment, self-oscillation drive circuit 1a comprises that the filter 11, starting drive 12, switching device Q1, the self-excitation that connect input voltage drive winding L 2, sampling apparatus Rs, Current Control control device 13 and drive unit 14.Switching device Q1 is pliotron, is included as base stage b1, emitter e 1 and collector electrode 113.Current control device 13 comprises switch element Q2, voltage-stabiliser tube Z2, resistance R 6 and resistance R 2.Switch element Q2 is pliotron, comprises base stage b2, emitter e 2 and collector electrode c2.Adopt voltage-stabiliser tube Z2, not only can change triggering level signal, the negative temperature characteristic of selecting the voltage-stabiliser tube of a positive temperature coefficient can also offset switch element Q2 base stage b2 and emitter e 2.Switching device Q1 is also pliotron, comprises base stage b1, emitter e 1 and collector electrode c1.Resistance R 12, as the bleeder resistance of switch element Q2, reduces the impact of voltage-stabiliser tube Z2 leakage current on switch element Q2 base stage b2.Increase when the variation of input voltage makes switching device Q1 electric current, resistance R 6 is adopted the voltage Vrs of sampling apparatus Rs.When the voltage Vrs of sampling apparatus Rs rises to certain value, trigger voltage stabilizing didoe Z2 work, now the base stage b2 of switch element Q2 has loaded voltage, and the electric current that flows into switch element Q2 base stage b2 reaches certain value, makes switch element Q2 conducting.After switch element Q2 conducting, the base stage b1 ground connection of switching device Q1, thus the base stage b1 of switching device Q1 and the pressure reduction of emitter e 1 are reduced, the electric current that flows into switching device Q1 base stage b1 does not reach the turn-on condition of switching device Q1 and turn-offs.Switching device Q1 closes and has no progeny, and the current peak that flows through switching device Q1 can not continue increase again, thereby it is excessive to have limited the output current fluctuation of self-oscillation drive circuit 1a.
Please refer to shown in Fig. 9, in the present invention's the second preferred embodiment, self-oscillation drive circuit 2a comprises the rectifying device 26, filter 21, starting drive 22, switching device Q1, transformer 25, sampling apparatus Rs, Current Control control device 23 and the drive unit 24 that connect input voltage.Transformer 25 comprises that winding L 1 and self-excitation drive winding L 2.Switching device Q1 is pliotron, is included as base stage b1, emitter e 1 and collector electrode c1.Current control device 23 comprises switch element Q2, voltage stabilizing didoe Z2, resistance R 2, resistance R 6 and voltage signal introducing device 231.Voltage signal introducing device 231 comprises resistance R 7.One end of resistance R 6 is connected with resistance R 7 and voltage stabilizing didoe Z2, and the other end is connected between sampling apparatus Rs and switching device Q1.One end and the voltage stabilizing didoe Z2 of resistance R 7 one end contact resistance R6, the other end connects self-excitation and drives winding L 2.Self-excitation drives winding L 2 voltage signals to be connected to voltage stabilizing didoe Z2 through resistance R 7 and resistance R 6 with sampled signal stack.Switch element Q2 is pliotron, comprises base stage b2, emitter e 2 and collector electrode c2.Switching device Q1 is also pliotron, comprises base stage b1, emitter e 1 and collector electrode c2.Resistance R 2, as the bleeder resistance of switch element Q2, reduces the impact of voltage stabilizing didoe Z2 leakage current on switch element Q2 base stage b2.Suppose that the voltage after rectifying device 26 is Vin, output voltage is Vo, and it is N that winding L 1 and self-excitation drive the turn ratio of winding L 2, and the voltage of voltage-stabiliser tube Z2 is VZ2, the base stage b2 of switch element Q2 and emitter e 2 forward conduction voltage drops are Vbe, and flowing through switching device Q1 collector electrode c1 electric current is IQ1.Can obtain from Fig. 9, in the time of switching device Q1 conducting, electric current I Q1 rises with certain slope, now winding L 1 both end voltage is Vin-Vo, the voltage that is coupled to self-excitation driving winding L 2 two ends is (Vin-Vo)/N, has following relational expression establishment in the time that electric current I Q1 arrives setting peak value, switch element Q2 work:
Can see from above formula, in the time that input and output voltage difference becomes large, electric current I Q1 peak value can correspondingly diminish, otherwise the strain of electric current I Q1 peak value meeting phase is large.In High Power Factor design application, input voltage vin presents sinusoidal wave peak shape, and electric current I Q1 peak value is corresponding presents sinusoidal trough shape; In the time of the work of different input voltage, the electric current I Q1 of high input voltage is little than the electric current I Q1 of low input, thereby reduces output current due to the variation causing of fluctuating of input voltage output voltage.Thereby it is excessive effectively to limit output current variation, and has increased constant current accuracy.
Please refer to shown in Figure 10, is the electric current I Q1 waveform schematic diagram of the first preferred embodiment and the second preferred embodiment, and wherein lines x is the envelope waveform while not adding any current control device; Lines y adds the envelope waveform after current control device 13 in the first preferred embodiment, and visible electric current I Q1 peak value obtains certain reduction; Lines z is the envelope waveform that adds current control device 23 in the second preferred embodiment, and electric current I Q1 peak value is further cut down.The result of test shows, in the second preferred embodiment, change ± 20% in the situation that at input voltage, output current change only have+1% and-4%; And change ± 13% in the situation that at output voltage, output current change only have ± 1%; Simultaneously, temperature test shows, add current control device the impact of constant current accuracy only had ° C of variation of ambient temperature ± 25 in the situation that ± 2.5%, experiment show add current control device very big improvement under different operating condition to output constant current characteristic.
In other embodiment, the topology of self-oscillation drive circuit is a variety of in addition, such as booster circuit formula self-oscillation drive circuit or other reduction voltage circuit formula self-oscillation drive circuits.The present invention is applicable to various self-oscillation drive circuits, is not limited with the embodiment being exemplified in specification.
Claims (10)
1. a self-oscillation drive circuit, comprise filter, drive unit, switching device, the sampling apparatus being connected with described switching device, and transformer, described transformer at least comprises that a self-excitation drives winding, the turn-on and turn-off of switching device described in described drive unit control, described drive unit, self-excitation drives winding, switching device and sampling apparatus form a loop, it is characterized in that: described self-oscillation drive circuit also comprises and is connected in described drive unit, self-excitation drives winding, current control device between the loop that switching device and sampling apparatus form is further to control described switching device.
2. self-oscillation drive circuit as claimed in claim 1, is characterized in that: the voltage controlled element that described current control device comprises switch element and is connected with switch element.
3. self-oscillation drive circuit as claimed in claim 2, is characterized in that: one end of described switch element connects described switching device and drive unit, the other end connects described voltage controlled element; One end of described voltage controlled element connects described switch element, and the other end connects between described sampling apparatus and switching device.
4. self-oscillation drive circuit as claimed in claim 2, it is characterized in that: described current control device also comprises voltage signal introducing device, described voltage signal introducing device one end connects self-excitation and drives winding, and the other end connects between sampling apparatus and switching device.
5. self-oscillation drive circuit as claimed in claim 4, is characterized in that: described voltage signal introducing device comprises impedance component and resistive element, and described impedor one end connects self-excitation and drives winding, and the other end connects described resistive element; Described resistive element one end connects described impedance component, and the other end connects between described sampling apparatus and switching device.
6. self-oscillation drive circuit as claimed in claim 5, is characterized in that: described impedance component can be electric capacity, resistance or their combination.
7. self-oscillation drive circuit as claimed in claim 1, it is characterized in that: described current control device comprises a stable-pressure device, one end of described stable-pressure device connects described drive unit and switching device, and the other end connects one end that described sampling apparatus is not connected with drive unit.
8. self-oscillation drive circuit as claimed in claim 7, is characterized in that: described stable-pressure device is voltage stabilizing didoe.
9. self-oscillation drive circuit as claimed in claim 8, it is characterized in that: described current control device also comprises voltage signal introducing device, described voltage signal introducing device one end connects self-excitation and drives winding, and the other end connects between sampling apparatus and switching device.
10. self-oscillation drive circuit as claimed in claim 9, is characterized in that: described voltage signal introducing device is diode, resistance, capacity cell or their combination.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310140843.7A CN104113957B (en) | 2013-04-22 | 2013-04-22 | A kind of self-oscillation drive circuit |
| CN201610090929.7A CN105722273B (en) | 2013-04-22 | 2013-04-22 | A kind of self-oscillation drive circuit |
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| CN201310140843.7A CN104113957B (en) | 2013-04-22 | 2013-04-22 | A kind of self-oscillation drive circuit |
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| CN201610090929.7A Division CN105722273B (en) | 2013-04-22 | 2013-04-22 | A kind of self-oscillation drive circuit |
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| CN104113957A true CN104113957A (en) | 2014-10-22 |
| CN104113957B CN104113957B (en) | 2016-08-24 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106507554A (en) * | 2015-09-06 | 2017-03-15 | 欧普照明股份有限公司 | A kind of LED self-excited drivings device |
| CN106507553A (en) * | 2015-09-06 | 2017-03-15 | 欧普照明股份有限公司 | A kind of LED self-excited drivings device |
| CN113824301A (en) * | 2021-09-10 | 2021-12-21 | 珠海格力电器股份有限公司 | Starting circuit of switching power supply and switching power supply thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201259180Y (en) * | 2008-05-13 | 2009-06-17 | 袁志华 | Highly effective LED illumination barrel lamp |
| CN201976288U (en) * | 2010-12-22 | 2011-09-14 | 张心益 | Drive power supply for LED illuminating light |
| CN102340906A (en) * | 2010-07-26 | 2012-02-01 | 美芯晟科技（北京）有限公司 | Dimming device for light emitting diode (LED) driving circuit |
| CN102665315A (en) * | 2012-05-29 | 2012-09-12 | 刘德军 | Household emergency fluorescent lamp |
| CN102711339A (en) * | 2012-06-21 | 2012-10-03 | 深圳市耀星光电子有限公司 | LED (Light Emitting Diode) drive circuit |
| JP2013012452A (en) * | 2011-06-28 | 2013-01-17 | Sanee Denki Kk | Power supply device for lighting apparatus |
| CN102905415A (en) * | 2011-07-29 | 2013-01-30 | 成都蜀昌科技有限公司 | LED (Light Emitting Diode) driving power supply without electrolytic capacitors |
-
2013
- 2013-04-22 CN CN201310140843.7A patent/CN104113957B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201259180Y (en) * | 2008-05-13 | 2009-06-17 | 袁志华 | Highly effective LED illumination barrel lamp |
| CN102340906A (en) * | 2010-07-26 | 2012-02-01 | 美芯晟科技（北京）有限公司 | Dimming device for light emitting diode (LED) driving circuit |
| CN201976288U (en) * | 2010-12-22 | 2011-09-14 | 张心益 | Drive power supply for LED illuminating light |
| JP2013012452A (en) * | 2011-06-28 | 2013-01-17 | Sanee Denki Kk | Power supply device for lighting apparatus |
| CN102905415A (en) * | 2011-07-29 | 2013-01-30 | 成都蜀昌科技有限公司 | LED (Light Emitting Diode) driving power supply without electrolytic capacitors |
| CN102665315A (en) * | 2012-05-29 | 2012-09-12 | 刘德军 | Household emergency fluorescent lamp |
| CN102711339A (en) * | 2012-06-21 | 2012-10-03 | 深圳市耀星光电子有限公司 | LED (Light Emitting Diode) drive circuit |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106507554A (en) * | 2015-09-06 | 2017-03-15 | 欧普照明股份有限公司 | A kind of LED self-excited drivings device |
| CN106507553A (en) * | 2015-09-06 | 2017-03-15 | 欧普照明股份有限公司 | A kind of LED self-excited drivings device |
| CN113824301A (en) * | 2021-09-10 | 2021-12-21 | 珠海格力电器股份有限公司 | Starting circuit of switching power supply and switching power supply thereof |
| CN113824301B (en) * | 2021-09-10 | 2023-09-12 | 珠海格力电器股份有限公司 | Starting circuit of switching power supply and switching power supply thereof |
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| CN104113957B (en) | 2016-08-24 |
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