Background technology
Please refer to Fig. 1.Fig. 1 is the schematic diagram of the light-source system 100 of a prior art.Light-source system 100 comprises power supply module 110, light emitting module 120 and current control module 130.
Power supply module 110 comprises 3 DC-DC converters (power supply) 111,112 and 113, is used for respectively with a DC voltage V who imports
INConvert DC voltage V to
OUTR, V
OUTG, V
OUTB, use to offer light emitting module 120.
Light emitting module 120 comprises three groups of light emitting diodes (Light Emitting Diode, LED) serial (luminous load) LED
R, LED
GAnd LED
BEvery group of light emitting diode serial can be made up of the light emitting diode of M series connection.For instance, light emitting diode serial LED
RThe light emitting diode that comprises M series connection.And light emitting diode serial LED
RSystem is made up of the red light-emitting diode of M series connection; Light emitting diode serial LED
GSystem is made up of the green light LED of M series connection; Light emitting diode serial LED
BSystem is made up of the blue light-emitting diode of M series connection.And the light emitting diode of every kind of color all has different forward bias voltage drop (forward voltage).For instance, the forward bias voltage drop of red light-emitting diode can be 2.4 volts, the forward bias voltage drop of green light LED and can be 3.1 volts, the forward bias voltage drop of blue light-emitting diode and can be 3.2 volts.Therefore, if M is set at 100, light emitting diode serial LED then
RRequired DC voltage V
OUTRJust be 240 volts, light emitting diode serial LED
GRequired DC voltage V
OUTGJust be 310 volts, light emitting diode serial LED
BRequired DC voltage V
OUTBJust be 320 volts.
Current control module 130 comprises three constant current source IS
R, IS
GAnd IS
BEach constant current source all is used to provide the electric current I of identical size
REFGive corresponding light emitting diode serial LED
R, LED
GAnd LED
B
And because light emitting diode serial LED
R, LED
GAnd LED
BNeed different DC voltage V respectively
OUTR, V
OUTGAnd V
OUTB, so 3 DC-DC converters of power supply module 110 minimum needs 111,112 and 113, could be with DC voltage V
INConvert DC voltage V to
OUTR, V
OUTG, V
OUTB, use to offer light emitting module 120.In other words, if more kinds of different light emitting diode serials are arranged in light emitting module 120, then power supply module 110 just needs how different DC-DC converters to produce required voltage, causes cost to rise, and reduces the convenience that the user uses light-source system 100.
Summary of the invention
Therefore the object of the present invention is to provide the light-source system that a kind of cost is low, convenience is good with single power supply.
The embodiment of the invention is to provide a kind of light-source system with single power supply.Described light-source system comprises first power supply, be used to provide first voltage, first luminous load, be electrically connected at described first power supply and be loaded with one second voltage, and according to the galvanoluminescence that is circulated, second luminous load, be electrically connected at described first power supply and be loaded with tertiary voltage, and according to the galvanoluminescence that is circulated, and voltage compensation module.Described voltage compensation module comprises transformer, first sensing apparatus, second sensing apparatus, error amplifier, work period adjuster, and a switch.Described transformer comprises the input coil circuit, be used to receive second source to produce the 4th voltage, described input coil circuit comprises the first predetermined wire circle, the first output winding circuit, be electrically connected at described first luminous load, comprise one second predetermined wire circle, be used to provide the 5th voltage, and the second output winding circuit, be electrically connected at described second luminous load, comprise the 3rd predetermined wire circle, be used to provide the 6th voltage.Wherein said the 4th voltage is to equal described the 5th voltage after being multiplied by the described first predetermined wire circle again divided by the described second predetermined wire circle.Wherein said the 4th voltage is to equal described the 6th voltage after being multiplied by the described first predetermined wire circle again divided by the described the 3rd predetermined wire circle.Described first sensing apparatus is to be electrically connected at the described first output winding circuit.Described second sensing apparatus is to be electrically connected at the described second output winding circuit.Described error amplifier comprises an input, be electrically connected at described first sensing apparatus and described second sensing apparatus, another input, be used to receive reference voltage, and output, described error amplifier is according to a described input of described error amplifier and the signal that described another input received of described error amplifier, output error signal.Described work period adjuster is electrically connected at the described output of described error amplifier, is used to receive described error signal to produce switch controlling signal according to this.Described switch is electrically connected between the described input coil circuit of described transformer and the ground end and described work period adjuster.Described open relation is according to the described input coil circuit of the described transformer of described switch controlling signal conducting and described the end.When the described input coil circuit of the described transformer of described switch conduction and described the end, described input coil circuit produces described the 4th voltage.When the described input coil circuit of the described transformer of not conducting of described switch and described the end, described input coil circuit does not produce described the 4th voltage.Described second voltage and described the 5th voltage and equal described first voltage, described tertiary voltage and described the 6th voltage with equal described first voltage.
The light-source system that the embodiment of the invention provides, can effectively utilize the voltage compensation module, compensate each light emitting diode string pressure reduction in the ranks, and make a plurality of light emitting diode serials can share same power supply, reduce the whole cost of luminescent system, and bigger convenience is provided.
The specific embodiment
In order to make purpose of the present invention, technical scheme and advantage clearer,, the present invention is further elaborated below in conjunction with drawings and Examples.Should be appreciated that specific embodiment described herein only in order to explanation the present invention, and be not used in qualification the present invention.
In the middle of specification and follow-up claim, used some vocabulary to censure specific assembly.The person with usual knowledge in their respective areas should understand, and same assembly may be called with different nouns by manufacturer.This specification and follow-up claim are not used as distinguishing the mode of assembly with the difference of title, but the benchmark that is used as distinguishing with the difference of assembly on function.Be an open term mentioned [comprising] in the middle of specification and the follow-up request item in the whole text, so should be construed to [including but not limited to].In addition, [electric connection] speech is to comprise any indirect means that are electrically connected that directly reach at this.Therefore, be electrically connected at second device, then represent this first device can be directly connected in this second device, or be connected to this second device indirectly by other device or connection means if describe first device in the literary composition.
Please refer to Fig. 2.The schematic diagram of the light-source system with single power supply 200 that Fig. 2 provides for the embodiment of the invention.As shown in Figure 2, light-source system 200 comprises power supply module 210, light emitting module 220, voltage compensation module 240 and current control module 230.
Power supply module 210 comprises single DC-DC converter (power supply) 211, is used for the DC voltage V with input
INConvert DC voltage V to
OUT, use to offer light emitting module 220.
Light emitting module 220 comprises three groups of light emitting diode serials (luminous load) LED
R, LED
GAnd LED
BEvery group of light emitting diode serial can be made up of the light emitting diode of M series connection, and every group of light emitting diode serial all is electrically connected at this DC-DC converter 211 to receive voltage V
OUTFor instance, light emitting diode serial LED
RThe light emitting diode that comprises M series connection.And light emitting diode serial LED
RRed light-emitting diode by M series connection is formed; Light emitting diode serial LED
GGreen light LED by M series connection is formed; Light emitting diode serial LED
BBlue light-emitting diode by M series connection is formed.And the light emitting diode of every kind of color all has different forward bias voltage drop.For instance, the forward bias voltage drop of red light-emitting diode can be 2.4 volts, the forward bias voltage drop of green light LED and can be 3.1 volts, the forward bias voltage drop of blue light-emitting diode and can be 3.2 volts.Therefore, if M is set at 100, light emitting diode serial LED then
RRequired DC voltage V
OUTRJust be 240 volts, light emitting diode serial LED
GRequired DC voltage V
OUTGJust be 310 volts, light emitting diode serial LED
BRequired DC voltage V
OUTBJust be 320 volts.
Current control module 230 comprises three constant current source IS
R, IS
GAnd IS
BEach constant current source all is electrically connected at corresponding light emitting diode serial LED
R, LED
GAnd LED
B, to be used to provide the electric current I of identical size
REFGive corresponding light emitting diode serial LED
R, LED
GAnd LED
BFor instance, constant current source IS
RBe electrically connected at light emitting diode serial LED
R, so that electric current I to be provided
REFGive light emitting diode serial LED
R
Voltage compensation module 240 comprises three voltage compensating devices 241,242 and 243.Voltage compensating device 241 is electrically connected at light emitting diode serial LED
RWith constant current source IS
RBetween; Voltage compensating device 242 is electrically connected at light emitting diode serial LED
GWith constant current source IS
GBetween; Voltage compensating device 243 is electrically connected at light emitting diode serial LED
BWith constant current source IS
BBetween.Voltage compensating device 241,242 and 243 is respectively applied for light emitting diode serial LED
R, LED
GAnd LED
BCarry out voltage compensation, so that single the output voltage V that DC-DC converter 211 is provided in the power supply module 210
OUTCan be by three different light emitting diode serial LED
R, LED
GAnd LED
BShare.In other words, voltage compensating device 241 compensable voltages are bucking voltage V
DR, voltage compensating device 242 compensable voltages are bucking voltage V
DG, voltage compensating device 243 compensable voltages are bucking voltage V
DBFor instance, the forward bias voltage drop of red light-emitting diode can be 2.4 volts, the forward bias voltage drop of green light LED and can be 3.1 volts, the forward bias voltage drop of blue light-emitting diode and can be 3.2 volts.Therefore, if M is set at 100, light emitting diode serial LED then
RRequired DC voltage V
OUTRJust be 240 volts, light emitting diode serial LED
GRequired DC voltage V
OUTGJust be 310 volts, light emitting diode serial LED
BRequired DC voltage V
OUTBJust be 320 volts.Therefore, can be with the output voltage V of DC-DC converter 211
OUTBe set at 330 volts, and bucking voltage V
DR, V
DGAnd V
DBCan be set at 90,20 and 10 volts respectively.The voltage that required DC-DC converter is exported in the light-source system 200 of the present invention thus just can be made as 330 volts, and sees through voltage compensation module 240, allows each light emitting diode serial LED
R, LED
GAnd LED
BShare.In other words, light-source system 200 required DC-DC converters of the present invention just only need one, just can drive different light emitting diode serials, and then save cost.In other words,, can make each light emitting diode serial share identical voltage source, to improve the convenience of light-source system 200 via the design of voltage compensation module 240.
Please refer to Fig. 3.Fig. 3 is the schematic diagram according to the voltage compensation module 240 of the first embodiment of the present invention.As shown in Figure 3, voltage compensating device 241,242 and 243 can be respectively with Zener diode (zener diode) ZN
R, ZN
GAnd ZN
BRealize.And according to aforesaid setting, the bucking voltage V that voltage compensating device 241,242 and 243 is required
DR, V
DGAnd V
DBBe respectively 90,20 and 10 volts.Therefore, can be with Zener diode ZN
R, ZN
GAnd ZN
BBreakdown voltage design just be 90,20 and 10 volts, to meet required bucking voltage V
DR, V
DGAnd V
DBThus, light emitting diode serial LED
RWith Zener diode ZN
RThe voltage that is consumed (240 volts+90 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
GWith Zener diode ZN
GThe voltage that is consumed (310 volts+20 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
BWith Zener diode ZN
BThe voltage that is consumed (320 volts+10 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; And can reach the effect of sharing single voltage source.
Please refer to Fig. 4.Fig. 4 is the schematic diagram of voltage compensation module 240 according to a second embodiment of the present invention.As shown in Figure 4, voltage compensating device 241,242 and 243 can be respectively with resistance R
R, R
GAnd R
BRealize.And according to aforesaid setting, the bucking voltage V that voltage compensating device 241,242 and 243 is required
DR, V
DGAnd V
DBBe respectively 90,20 and 10 volts.Therefore, can be with resistance R
R, R
GAnd R
B, according to electric current I
REFSize, set suitable resistance, so that resistance R
R, R
GAnd R
BCross-pressure just be 90,20 and 10 volts, to meet required bucking voltage V
DR, V
DGAnd V
DB, meaning is a resistance R
RResistance and electric current I
REFProduct equal bucking voltage V
DR, resistance R
GResistance and electric current I
REFProduct equal bucking voltage V
DG, resistance R
BResistance and electric current I
REFProduct equal bucking voltage V
DBThus, light emitting diode serial LED
RWith resistance R
RThe voltage that is consumed (240 volts+90 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
GWith resistance R
GThe voltage that is consumed (310 volts+20 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
BWith resistance R
BThe voltage that is consumed (320 volts+10 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; And can reach the effect of sharing single voltage source.
Please refer to Fig. 5.Fig. 5 is the schematic diagram of the voltage compensation module 240 of a third embodiment in accordance with the invention.As shown in Figure 5, voltage compensation module 240 can realize with transformer.Call voltage compensation module 240 in the following text and be transformer 240.And transformer 240 can comprise an input coil circuit TI and three output winding circuit T
R, T
GAnd T
BAnd voltage compensating device 241,242 and 243 just is respectively output winding circuit T
R, T
GAnd T
BInput coil circuit T
ISystem is used to receive input voltage V
IN, produce voltage V according to this
XAnd output winding circuit T
R, T
GAnd T
BThe cross-pressure that is produced just can with voltage V
X, input coil circuit T
IThe number of turns that is wound the line, output winding circuit T
RThe wire circle that is wound the line, output winding circuit T
GWire circle that is wound the line and output winding circuit T
BThe wire circle that is wound the line is relevant.And in this embodiment, voltage V
INCan equal voltage V
XFor instance, output winding circuit T
RThe cross-pressure V that is produced
DRCan equal voltage V
XThe wire circle that is multiplied by output winding circuit TR is again divided by the wire circle (V of input coil circuit TI
X/ N1=V
DR/ N2, wherein N1 is that the number of turns, the N2 of input coil circuit TI are output winding circuit T
RThe number of turns).And according to aforesaid setting, the bucking voltage V that voltage compensating device 241,242 and 243 is required
DR, V
DGAnd V
DBBe respectively 90,20 and 10 volts.Therefore, can be with coil circuit T
I, T
R, T
GAnd T
B, according to voltage V
XSize, set the suitable number of turns, so that output winding circuit T
R, T
GAnd T
BCross-pressure just be 90,20 and 10 volts, to meet required bucking voltage V
DR, V
DGAnd V
DBThus, light emitting diode serial LE
DRWith output winding circuit T
RThe voltage that is consumed (240 volts+90 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
GWith output winding circuit T
GThe voltage that is consumed (310 volts+20 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; Light emitting diode serial LED
BWith output winding circuit T
BThe voltage that is consumed (320 volts+10 volts) just can be just and the output voltage V of DC-DC converter
OUT(330 volts) are identical; And can reach the effect of sharing single voltage source.
Please refer to Fig. 6.Fig. 6 is the schematic diagram of the voltage compensation module 250 of a fourth embodiment in accordance with the invention.As shown in Figure 6, voltage compensating device 241,242 and 243, similar to Fig. 5, can be respectively with output winding circuit T
R, T
GAnd T
BRealize.And voltage compensating device 250 is with disclosed voltage compensating device 240 differences of Fig. 5: voltage compensating device 250 has increased voltage sensing device SV in addition newly
R, SV
GAnd SV
B, error amplifier EA, work period adjuster 251 and switch SW
1
Voltage sensing device SV
RCan a resistance R
SRAn and diode D
SRRealize, be electrically connected at this output winding circuit T
R, be used to detect light emitting diode serial LED
RWith output winding circuit T
RThe pressure drop of summation; Voltage sensing device SV
GCan a resistance R
SGAn and diode D
SGRealize, be electrically connected at this output winding circuit T
G, be used to detect light emitting diode serial LED
GWith output winding circuit T
GThe pressure drop of summation; Voltage sensing device SV
BCan a resistance R
SBAn and diode D
SBRealize, be electrically connected at this output winding circuit T
B, be used to detect light emitting diode serial LED
BWith output winding circuit T
BThe pressure drop of summation.
Error amplifier EA comprises two inputs and an output.The input of error amplifier EA is electrically connected at voltage sensing device SV
R, SV
GAnd SV
B, be used to detect light emitting diode serial LED
RWith output winding circuit T
RThe pressure drop of summation, light emitting diode serial LED
GWith output winding circuit T
GThe pressure drop of summation and light emitting diode serial LED
BWith output winding circuit T
BThe worst situation among the pressure drop three of summation.Another input of error amplifier EA is used to receive a reference voltage V
REFAnd error amplifier EA produces an error signal S according to the signal that is received
ER
Work period adjuster 251 is used for according to error signal S
ER, produce a switch controlling signal S
PWMSwitch controlling signal S
PWMIt can be a pulse width modulation signal.That is to say switch controlling signal S
PWMCan be one and have the periodic signal that the cycle is TD.And at switch controlling signal S
PWMOne-period in, accurate the shared ratio in accurate position of its high voltage and low-voltage be for adjusting, i.e. switch controlling signal S
PWMDutycycle for adjusting.
Switch SW
1Be electrically connected at a bias generator V
SS(hold) and input coil circuit T
IBetween, be used for according to switch controlling signal S
PWM, with input coil circuit T
IWith bias generator V
SSElectrically connect.Work as switch SW
1According to switch controlling signal S
PWMDuring with unlatching (conducting), input coil circuit T
IBe electrically connected at bias generator V
SS, therefore this moment input coil circuit T
IThe voltage V that is produced
XBe input voltage V
IN, and output winding circuit T
R, T
GAnd T
BThe voltage that is produced also is V
DR, V
DGAnd V
DBOtherwise, work as switch SW
1According to switch controlling signal S
PWMWhen closing (not conducting), input coil circuit T
IWith bias generator V
SSElectric connection disconnect, therefore this moment input coil circuit T
IThe voltage V that is produced
XJust be zero, and output winding circuit T
R, T
GAnd T
BThe voltage that is produced also is all zero.
And according to above-mentioned design, can see through and adjust switch controlling signal S
PWMThe responsibility ratio, to adjust average bucking voltage V
DR, V
DGAnd V
DBBecause when temperature rises, the forward bias voltage drop of light emitting diode can change but not be definite value, and above-mentioned design can thus the size of change bucking voltage, make the output voltage V of DC-DC converter 211
OUTStill can be applicable to the light emitting diode serial under the situation that temperature rises.More particularly, voltage compensation module 250 more can improve the scope of application of voltage compensation module 250 dynamically along with the voltage that forward voltage changes and change is compensated of light emitting diode.
In sum, light-source system provided by the present invention can effectively utilize the voltage compensation module, compensate each light emitting diode string pressure reduction in the ranks, and make a plurality of light emitting diode serials can share same power supply, reduce the whole cost of luminescent system, and bigger convenience is provided.
The above only is preferred embodiment of the present invention, not in order to restriction the present invention, all any modifications of being done within the spirit and principles in the present invention, is equal to and replaces and improvement etc., all should be included within protection scope of the present invention.