CN103874288B - A kind of light-emitting diode light bar drive circuit and LCD TV - Google Patents
A kind of light-emitting diode light bar drive circuit and LCD TV Download PDFInfo
- Publication number
- CN103874288B CN103874288B CN201410004753.XA CN201410004753A CN103874288B CN 103874288 B CN103874288 B CN 103874288B CN 201410004753 A CN201410004753 A CN 201410004753A CN 103874288 B CN103874288 B CN 103874288B
- Authority
- CN
- China
- Prior art keywords
- voltage
- circuit
- emitting diode
- light
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000003750 conditioning effect Effects 0.000 claims abstract description 113
- 238000000034 method Methods 0.000 claims description 34
- 230000008569 process Effects 0.000 claims description 32
- 238000005070 sampling Methods 0.000 claims description 17
- 238000001914 filtration Methods 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 230000005669 field effect Effects 0.000 description 17
- 238000010586 diagram Methods 0.000 description 11
- 230000008859 change Effects 0.000 description 7
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
Embodiments provide a kind of LED lamp bar drive circuit and LCD TV, in order to solve existing LED lamp bar drive circuit due to cannot the voltage at dynamic conditioning LED lamp bar two ends, make the problem that its scope of application is narrower.This circuit comprises: driving voltage output circuit, for the direct voltage received being converted under the control of control signal that exports at control circuit the driving voltage of LED and the voltage exported as the anode of LED lamp bar, and exporting the first conditioning signal to control circuit, its voltage proportional is in the voltage of the anode of LED lamp bar; Dynamic electric voltage feedback circuit, for the voltage difference of the first predeterminated voltage of the sampled value and this LED lamp bar of determining the negative terminal voltage of each LED lamp bar be connected with self, and generates the second conditioning signal according to the voltage difference determined and exports control circuit to; Control circuit, for according to the second predeterminated voltage, the first conditioning signal and the second conditioning signal, generates control signal.
Description
Technical field
The present invention relates to the power technique fields of LCD TV, particularly relate to a kind of light-emitting diode light bar drive circuit and LCD TV.
Background technology
Light-emitting diode (LED, LightEmittingDiode) as the backlight of LCD TV, shutter 3D TV can have the even more lamp bars in six tunnels at least.Power drives mode is generally: LLC resonant circuit exports two-way voltage signal, wherein a road voltage signal drives a paths of LEDs lamp bar under the control of booster circuit, have several lamp bars just to need several booster circuit, thus the electric current realizing every street lamp bar is equal, to meet television image display requirement; Or the electric current that the mode of employing linear voltage stabilization realizes each lamp bar is equal, so still at least needs a road boosting to drive, make Circuits System become two-stage, to reach the object of constant control.
Such as, the framework of the drive circuit adopted in current a kind of shutter 3DLED LCD TV is: by power factor correction (PFC, PowerFactorCorrection) the Power supply part that circuit and LLC half-bridge resonance circuit are formed exports two-way voltage signal, LED drive circuit part comprises for Boost circuit provides pulse width modulation (PWM, PulseWidthModulation) micro-processing and control element (PCE) (MCU, MicroprocessorControlUnit) chip of signal and Boost circuit.Wherein, MCU chip can control Boost circuit and provide constant current output for LED lamp bar, also can control the voltage of Boost circuit output all near reference voltage.Because this LED drive circuit is after setting reference voltage, due to cannot the voltage at LED lamp bar two ends that connects of this LED lamp bar drive circuit of dynamic conditioning, this just causes the scope of application of this LED drive circuit narrower.
In sum, current LED lamp bar drive circuit is after setting reference voltage, and due to cannot the voltage at LED lamp bar two ends that connects of this LED lamp bar drive circuit of dynamic conditioning, the scope of application which results in this LED lamp bar drive circuit be very narrow.
Summary of the invention
Embodiments provide a kind of light-emitting diode light bar drive circuit and LCD TV, in order to solve existing LED lamp bar drive circuit after setting reference voltage, due to cannot the voltage at LED lamp bar two ends that connects of this LED lamp bar drive circuit of dynamic conditioning, make the problem that the scope of application of this LED lamp bar drive circuit is narrower.
Based on the problems referred to above, a kind of LED driving circuit that the embodiment of the present invention provides, comprises control circuit, driving voltage output circuit and dynamic electric voltage feedback circuit;
Described driving voltage output circuit, for receiving the control signal of described control circuit, under the control of said control signal the direct voltage received be converted into the driving voltage of LED and output to the anode of LED lamp bar, and exporting the first conditioning signal to described control circuit, the voltage proportional of described first conditioning signal is in the voltage of the anode of described LED lamp bar;
Described dynamic electric voltage feedback circuit, for the voltage difference of the first predeterminated voltage of the sampled value and this LED lamp bar of determining the negative terminal voltage of each LED lamp bar be connected with self, and generate the second conditioning signal according to the voltage difference determined and export described control circuit to;
Described control circuit, for the second conditioning signal exported according to the first conditioning signal and the described dynamic electric voltage feedback circuit of the second predeterminated voltage, the output of described driving voltage output circuit, generate described control signal and export described driving voltage output circuit to;
Described control circuit specifically for: the second conditioning signal that the first conditioning signal exported according to the second predeterminated voltage, described driving voltage output circuit and described dynamic electric voltage feedback circuit export generates the first control signal and the second control signal, and exports the first control signal and the second control signal to driving voltage output circuit; Described first control signal and described second control signal complementation;
Described driving voltage output circuit comprises the first transformer, LLC half-bridge resonance circuit, the second transformer, light-emitting diode voltage follower circuit and tertiary voltage sample circuit;
Described LLC half-bridge resonance circuit, for receiving described first control signal and described second control signal by described first transformer, and under the control of described first control signal and described second control signal, the direct voltage received is converted to alternating voltage, by resonance, described alternating voltage is exported to described light-emitting diode voltage follower circuit by described second transformer;
Described light-emitting diode voltage follower circuit, the driving voltage for the alternating voltage received being converted to light-emitting diode outputs to the anode of light-emitting diode light bar;
Described tertiary voltage sample circuit, for gathering the voltage that described light-emitting diode voltage follower circuit exports, and export the first conditioning signal to described control circuit, the voltage proportional of described first conditioning signal is in the voltage of the anode of described light-emitting diode light bar.
A kind of LCD TV that the embodiment of the present invention provides, comprises the LED driving circuit that the embodiment of the present invention provides.
The beneficial effect of the embodiment of the present invention comprises:
A kind of light-emitting diode light bar drive circuit that the embodiment of the present invention provides and LCD TV, by control circuit according to the second predeterminated voltage, the first conditioning signal that driving voltage output circuit exports and the second conditioning signal that dynamic electric voltage feedback circuit exports generate control signal, and the direct voltage received is converted into the driving voltage of LED and outputs to the anode of LED lamp bar by driving voltage output circuit under the control of this control signal, and export the first conditioning signal to control circuit, the voltage proportional of this first conditioning signal is in the voltage of the anode of LED lamp bar, thus make control circuit and driving voltage output circuit form closed-loop system, make driving voltage output circuit can stablize the driving voltage exporting LED, dynamic electric voltage feedback circuit, can determine the voltage difference of the sampled value of the negative terminal voltage of each LED lamp bar be connected with self and the first predeterminated voltage of this LED lamp bar, and generates the second conditioning signal according to the voltage difference determined and export described control circuit to, thus can by changing the first predeterminated voltage of LED lamp bar, regulate the voltage that driving voltage output circuit exports dynamically, make LED driving circuit can provide one near reference voltage (when dynamic electric voltage feedback circuit is not started working, the voltage that driving voltage output circuit exports is reference voltage) and the wider LED driving voltage of adjustable range, expand the scope of application of light-emitting diode light bar drive circuit.
Accompanying drawing explanation
One of schematic diagram of the LED lamp bar drive circuit that Fig. 1 provides for the embodiment of the present invention;
The schematic diagram two of the LED lamp bar drive circuit that Fig. 2 provides for the embodiment of the present invention;
The schematic diagram three of the LED lamp bar drive circuit that Fig. 3 provides for the embodiment of the present invention;
The schematic diagram four of the LED lamp bar drive circuit that Fig. 4 provides for the embodiment of the present invention;
The schematic diagram five of the LED lamp bar drive circuit that Fig. 5 provides for the embodiment of the present invention;
The schematic diagram six of the LED lamp bar drive circuit that Fig. 6 provides for the embodiment of the present invention;
The schematic diagram seven of the LED lamp bar drive circuit that Fig. 7 provides for the embodiment of the present invention;
The schematic diagram eight of the LED lamp bar drive circuit that Fig. 8 provides for the embodiment of the present invention;
The schematic diagram nine of the LED lamp bar drive circuit that Fig. 9 provides for the embodiment of the present invention;
The schematic diagram ten of the LED lamp bar drive circuit that Figure 10 provides for the embodiment of the present invention.
Embodiment
A kind of light-emitting diode light bar drive circuit of the embodiment of the present invention and LCD TV, the control signal of control circuit output is changed by the first predeterminated voltage changing LED lamp bar, and the voltage of dynamic adjustments driving voltage output circuit output is carried out by control signal, make light-emitting diode light bar drive circuit can provide one near reference voltage and the wider LED driving voltage of adjustable range, expand the scope of application of light-emitting diode light bar drive circuit.
Below in conjunction with Figure of description, a kind of light-emitting diode light bar drive circuit provide the embodiment of the present invention and the embodiment of LCD TV are described.
A kind of light-emitting diode light bar drive circuit that the embodiment of the present invention provides, as shown in Figure 1, specifically comprises control circuit 11, driving voltage output circuit 12 and dynamic electric voltage feedback circuit 13;
Driving voltage output circuit 12, for the control signal of reception control circuit 11, under control of the control signal the direct voltage received be converted into the driving voltage of pipe LED and output to the anode LED+ of LED lamp bar, and exporting the first conditioning signal to described control circuit 11, the voltage proportional of this first conditioning signal is in the voltage of the anode LED+ of LED lamp bar;
Dynamic electric voltage feedback circuit 13, for the voltage difference of the sampled value of negative terminal LED-voltage and the first predeterminated voltage of this LED lamp bar of determining each LED lamp bar be connected with self, and generate the second conditioning signal according to the voltage difference determined and export described control circuit 11 to.
Control circuit 11, for the second conditioning signal exported according to the first conditioning signal and the dynamic electric voltage feedback circuit 13 of the second predeterminated voltage, driving voltage output circuit 12 output, generates control signal and also exports driving voltage output circuit 12 to.
In application scenarios one, dynamic electric voltage feedback circuit connects the negative terminal of 3 LED lamp bar, be respectively LED-1, LED-2 and LED-3, the sampled value of the voltage on LED-1 is VS1, the sampled value of the voltage on LED-2 is VS2, the sampled value of the voltage on LED-3 is VS3, the anode of these 3 LED lamp bar links together, and receive the driving voltage of the LED that driving voltage output circuit exports, if the first predeterminated voltage of LED-1 lamp bar is V1, first predeterminated voltage of LED-2 lamp bar is V2, first predeterminated voltage of LED-3 lamp bar is V3, then dynamic electric voltage feedback circuit determines that the voltage difference of the sampled value of the negative terminal voltage of each LED lamp bar be connected with self and the first predeterminated voltage of this LED lamp bar is respectively VS1-V1, VS2-V2 and VS3-V3.Wherein, the voltage of the negative terminal of this LED lamp bar when the first predeterminated voltage of a LED lamp bar refers to that this LED lamp bar normally works.
Wherein, the second conditioning signal can be level signal, also can be pulse signal.If the second conditioning signal is pulse signal, then control circuit is also for being converted to level signal by pulse signal, and according to the second predeterminated voltage, generate control signal from the first conditioning signal of driving voltage output circuit and the voltage changed by pulse signal and export to driving voltage output circuit.That is, when the second conditioning signal is pulse signal, only needs in control circuit, increase function pulse signal being converted to level signal, the operation principle of the LED drive circuit that the embodiment of the present invention provides is not had an impact.Below only for the second conditioning signal for level signal illustrates the LED drive circuit that the embodiment of the present invention provides.
Further, dynamic electric voltage feedback circuit is specifically for the voltage difference of determining the sampled value of the negative terminal voltage of each LED lamp bar be connected with self and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export described control circuit to; If the setting rule value of the voltage difference determined is in preset range, then described second conditioning signal is provided for described control circuit and generates the control signal not changing the positive terminal voltage of LED lamp bar; If the setting rule value of the voltage difference determined is less than the minimum value of preset range, then described second conditioning signal is provided for described control circuit and generates the control signal that can improve the positive terminal voltage of LED lamp bar; If the setting rule value of the voltage difference determined is greater than the maximum of preset range, then described second conditioning signal is provided for described control circuit and generates the control signal that can reduce the positive terminal voltage of LED lamp bar;
Wherein, the setting rule value of the voltage difference determined is the mean value of the voltage difference determined or the minimum value of voltage difference determined.
In application scenarios one, the setting rule value of the voltage difference that dynamic electric voltage feedback circuit is determined is the mean value of VS1-V1, VS2-V2 and VS3-V3, or, the minimum value in VS1-V1, VS2-V2 and VS3-V3.
After the power-up, control circuit is according to the second predeterminated voltage, the first conditioning signal that driving voltage output circuit exports and the second conditioning signal that dynamic electric voltage feedback circuit exports generate control signal and export driving voltage output circuit to, the direct voltage received is converted into the driving voltage of LED and outputs to the anode of LED lamp bar by driving voltage output circuit under the control of this control signal, and export the first conditioning signal to control circuit, the voltage proportional of this first conditioning signal is in the voltage of the anode of LED lamp bar, thus form a closed loop mini system, export stable LED+ voltage when initially powering on, i.e. reference voltage.Simultaneously, dynamic electric voltage feedback circuit determines the voltage difference of the sampled value of the negative terminal voltage of each LED lamp bar be connected with self and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export described control circuit to, when the setting rule value of the voltage difference determined is less than the minimum value of preset range, the second conditioning signal generated is provided for control circuit and generates the control signal that can improve the positive terminal voltage of LED lamp bar, the voltage that this control signal can make driving voltage output circuit output to LED lamp bar anode is raised, thus make the setting rule value connecting the negative terminal terminal voltage of each LED lamp bar of dynamic electric voltage feedback circuit and the difference of the first predeterminated voltage of this LED lamp bar in preset range, then dynamic electric voltage feedback circuit completes the control to control circuit, whole LED lamp bar drive circuit enters the state of steady operation, when the setting rule value of the voltage difference determined is greater than the maximum of preset range, the second conditioning signal generated is provided for control circuit and generates the control signal that can reduce the positive terminal voltage of LED lamp bar, the voltage that this control signal can make driving voltage output circuit output to the anode of LED lamp bar reduces, thus make the setting rule value connecting the negative terminal terminal voltage of each LED lamp bar of dynamic electric voltage feedback circuit and the difference of the first predeterminated voltage of this LED lamp bar in preset range, then dynamic electric voltage feedback circuit completes the control to control circuit, whole LED lamp bar drive circuit enters the state of steady operation, when the setting rule value of the voltage difference determined is in preset range, the second conditioning signal of generation is provided for control circuit and generates the control signal not changing the positive terminal voltage of LED lamp bar, whole LED drive circuit steady operation.
Further, dynamic electric voltage feedback circuit is also for before the voltage difference of the sampled value of negative terminal voltage and the first predeterminated voltage of this LED lamp bar of determining each LED lamp bar be connected with self, determine that the negative terminal voltage of at least one LED lamp bar be connected with self equals zero, and generate the second conditioning signal and export described control circuit to, described second conditioning signal is provided for described control circuit and generates and makes the positive terminal voltage of LED lamp bar be less than the control signal of the driving voltage of LED lamp bar.
That is, dynamic electric voltage feedback circuit is before the voltage difference of the sampled value of negative terminal voltage and the first predeterminated voltage of this LED lamp bar of determining each LED lamp bar be connected with self, the voltage of the negative terminal judging each LED lamp bar be connected with self is also needed whether to be zero, namely whether each LED lamp bar connects normally, when LED lamp bar is normal, after LED lamp bar drive circuit works on power, the voltage of the negative terminal of LED lamp bar can not be zero.Therefore, dynamic electric voltage feedback circuit is when determining that the negative terminal voltage of the LED lamp bar be connected with self equals zero, also this LED lamp bar generation open circuit is just determined, now dynamic electric voltage feedback circuit generates the second conditioning signal, this second conditioning signal controls control circuit generation makes the positive terminal voltage of LED lamp bar be less than the control signal of the driving voltage of LED lamp bar, thus prompting has LED lamp bar generation open circuit, waits LED lamp bar to be replaced.
Further, the dynamic electric voltage feedback circuit in the LED lamp bar drive circuit that provides of the embodiment of the present invention can also adopt the circuit structure shown in Fig. 2.As shown in Figure 2, dynamic electric voltage feedback circuit specifically comprises first process chip 132 and at least one first voltage sampling circuit 131;
Each first voltage sampling circuit 131, the sampled value for the negative terminal voltage of this LED lamp bar obtained of being sampled by the negative terminal from the LED lamp bar be connected with self exports to the first process chip 132;
According to the voltage from each the first voltage sampling circuit 131 be connected with self, first process chip, for judging whether that the voltage of the negative terminal of at least one LED lamp bar is zero; If so, then generate the second conditioning signal and export control circuit 11 to, this second conditioning signal is provided for control circuit 11 generation makes the voltage of the anode LED+ of LED lamp bar be less than the control signal of the driving voltage of LED lamp bar; Otherwise, determine the voltage difference of the sampled value of the voltage of the negative terminal LED-of each LED lamp bar and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export control circuit 11 to; When the setting rule value of the voltage difference determined is in preset range, this second conditioning signal is provided for the control signal that control circuit 11 generates the voltage not changing LED lamp bar anode LED+; When the setting rule value of the voltage difference determined is less than the minimum value of preset range, this second conditioning signal is provided for control circuit 11 and generates the control signal that can improve the voltage of the anode LED+ of LED lamp bar; When the setting rule value of the voltage difference determined is greater than the maximum of preset range, this second conditioning signal is provided for control circuit 11 and generates the control signal that can reduce the voltage of the anode LED+ of LED lamp bar.
Further, as shown in Figure 3, each first voltage sampling circuit comprises the first diode D1, the 4th resistance R4 and the 5th resistance R5;
The negative electrode of the first diode D1 connects the negative terminal LED-of LED lamp bar, and the anode of the first diode D1 connects one end of the 4th resistance R4, and the other end of the 4th resistance R4 connects one end of the 5th resistance R5, the other end ground connection of the 5th resistance R5; The voltage sampled is exported to the first process chip 132 by the one end be connected with the 5th resistance R5 in the 4th resistance R4.
Further, the dynamic electric voltage feedback circuit in the LED lamp bar drive circuit that provides of the embodiment of the present invention can also adopt the circuit structure shown in Fig. 4.As shown in Figure 4, dynamic electric voltage feedback circuit specifically comprises the second process chip 134, voltage regulator circuit 135 and at least one the second voltage sampling circuit 133;
Each second voltage sampling circuit 133, the sampled value for the negative terminal voltage of this LED lamp bar obtained of being sampled by the negative terminal from the LED lamp bar be connected with self exports to the second process chip 134;
According to the voltage from each the second voltage sampling circuit 133 be connected with self, second process chip 134, for judging whether that the voltage of the negative terminal LED-of at least one LED lamp bar is zero; If, then production burst signal exports voltage regulator circuit 135 to, described pulse signal is converted to the second conditioning signal by voltage regulator circuit 135, and this second conditioning signal makes the voltage of the anode LED+ of LED lamp bar be less than the control signal of the driving voltage of LED lamp bar for controlling control circuit 11 generation; Otherwise, determine the voltage difference of the sampled value of the voltage of the negative terminal LED-of each LED lamp bar and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and production burst signal exports voltage regulator circuit 135 to; When the setting rule value of the voltage difference determined is in preset range, described pulse signal is converted to the second conditioning signal by voltage regulator circuit 135, and this second conditioning signal generates the control signal of the positive terminal voltage not changing LED lamp bar for controlling control circuit 11; When the setting rule value of the voltage difference determined is less than the minimum value of preset range, described pulse signal is converted to the second conditioning signal by voltage regulator circuit 135, and this second conditioning signal generates the control signal that can improve the voltage of the anode LED+ of LED lamp bar for controlling control circuit 11; When the setting rule value of the voltage difference determined is greater than the maximum of preset range, described pulse signal is converted to the second conditioning signal by voltage regulator circuit 135, and this second conditioning signal generates the control signal that can reduce the positive terminal voltage of LED lamp bar for controlling control circuit 11;
Voltage regulator circuit 135, for being converted to the second conditioning signal by the pulse signal from the second process chip 134 by filtering and dividing potential drop.
Wherein, the second voltage sampling circuit can adopt the structure identical with the first voltage sampling circuit.
Further, as shown in Figure 5, voltage regulator circuit comprises the first resistance R1, second resistance R2, 3rd resistance R3 and the first electric capacity C1, one end ground connection after 3rd resistance R3 is in parallel with the first electric capacity C1, the other end connects one end of the first resistance R1 and one end of the second resistance R2 respectively, the other end of the first resistance R1 receives the pulse signal of the second process chip 134 output, this pulse signal is through the first resistance R1 and the 3rd resistance R3 dividing potential drop, and direct voltage is converted to after the first electric capacity C1 filtering, and be transferred to control circuit 11 by the second resistance R2, wherein, the signal that second resistance R2 is transferred to control circuit 11 is the second conditioning signal.
Below only for the LED lamp bar drive circuit that dynamic electric voltage feedback circuit adopts the structure shown in Fig. 2 to provide so that the embodiment of the present invention to be described.The operation principle of the LED lamp bar drive circuit that the embodiment of the present invention provides when dynamic electric voltage feedback circuit adopts the structure shown in Fig. 2, when adopting the structure shown in Fig. 4 with dynamic electric voltage feedback circuit, the operation principle of the LED lamp bar drive circuit that the embodiment of the present invention provides is identical, does not repeat them here.
Further, the LED lamp bar drive circuit that the embodiment of the present invention provides, also comprises at least one LED constant current circuit; Each LED constant current circuit, for determining according to the reference voltage of setting the electric current flowing through a LED lamp bar, and controls described current constant.
Wherein, reference voltage can be arranged on the inside of each LED constant current circuit, also can by a process chip separately for each LED constant current circuit provides reference voltage.
When having the 3rd process chip separately to provide reference voltage for each LED constant current circuit, the LED lamp bar drive circuit that the embodiment of the present invention provides, as shown in Figure 6, also comprises at least one LED constant current circuit 14 and the 3rd process chip 15;
Each LED constant current circuit 14, for determining to flow through the electric current of a LED lamp bar according to the reference voltage received, and controls described current constant;
3rd process chip 15, for each LED constant current circuit 14 output reference voltage be connected with self.
Wherein, the function of the 3rd process chip 15 can be integrated in the first process chip 132, also can be integrated in the second process chip 134, can also be realized by the chip arranged separately.
Further, as shown in Figure 7, each LED constant current circuit in the LED drive circuit that provides of the embodiment of the present invention comprises the first operational amplifier A 1, first triode T1 and the 6th resistance R6;
The collector electrode of the first triode T1 connects the negative terminal LED-of described LED lamp bar, the base stage of the first triode T1 connects the output of described first operational amplifier A 1, the emitter of the first triode T1 connects the inverting input of the first operational amplifier A 1 and one end of the 6th resistance R6 respectively, the other end ground connection of the 6th resistance R6, the in-phase input end of the first operational amplifier A 1 receives the reference voltage of the second process chip 15 output.First operational amplifier A 1 controls to flow through the current constant of LED lamp bar according to the reference voltage that the 3rd process chip 15 provides.
LED constant current circuit in Fig. 7 be one from constant-current circuit.
Further, control circuit in the LED drive circuit that the embodiment of the present invention provides as shown in Figure 8, specifically for: the second conditioning signal that the first conditioning signal exported according to the second predeterminated voltage, driving voltage output circuit and dynamic electric voltage feedback circuit export generates the first control signal and the second control signal, and exports the first control signal and the second control signal to driving voltage output circuit; Described first control signal and described second control signal complementation.Wherein, when first control signal and the second control signal complementation refer to that the first control signal is high level, the second control signal is low level, when the second control signal is high level, first control signal is low level, and the first control signal and the second control signal are the signal of frequency-adjustable.
Wherein, the control signal in Fig. 1 includes the first control signal and the second control signal.First control signal and the second control signal are the signals of frequency-adjustable.
Further, driving voltage output circuit in the LED lamp bar drive circuit that the embodiment of the present invention provides, as shown in Figure 9, the first transformer 121, LLC half-bridge resonance circuit 122, second transformer 123, LED electrical voltage follower circuit 124 and tertiary voltage sample circuit 125 is comprised;
LLC half-bridge resonance circuit 122, for receiving the first control signal and the second control signal by the first transformer 121, and under the control of the first control signal and the second control signal, the direct voltage received is converted to alternating voltage, by resonance, described alternating voltage is exported to LED electrical voltage follower circuit 124 by the second transformer 123;
LED electrical voltage follower circuit 124, the driving voltage for the alternating voltage received being converted to LED outputs to the anode LED+ of LED lamp bar;
Tertiary voltage sample circuit 125, for gathering the voltage that LED electrical voltage follower circuit 124 exports, and export the first conditioning signal to control circuit, the voltage proportional of this first conditioning signal in the voltage of the anode of this LED lamp bar, i.e. the voltage that exports in LED electrical voltage follower circuit 124 of the voltage proportional of this first conditioning signal.
Further, as shown in Figure 10, one end of the secondary coil of the first transformer 121 receives the first control signal, the other end of the secondary coil of the first transformer 121 receives the second control signal, the signal that secondary coil from the first transformer 121 is coupled to is exported to LLC half-bridge resonance circuit by first group of primary coil of the first transformer 121, and the signal that the secondary coil from the first transformer 121 is coupled to is exported to LLC half-bridge resonance circuit by second group of primary coil of the first transformer 121.
Secondary the first control signal of receiving and the second control signal, in order to isolate the interference between primary and secondary, are delivered to voltage that is elementary and that isolate between primary and secondary by the first transformer.
LLC half-bridge resonance circuit comprises the second electric capacity C2, the second diode D2, the 3rd diode D3, the 4th diode D4, the 5th diode D5, the 7th resistance R7, the 8th resistance R8, the 9th resistance R9, the tenth resistance R10, the 11 resistance R11, the 12 resistance R12, the first field effect transistor M1 and the second field effect transistor M2, 7th resistance R7 is connected between the two ends of first group of primary coil of the first transformer 121 after connecting with the 9th resistance R9, the negative electrode of the second diode D2 connects one end of first group of primary coil of the first transformer 121, the anode of the second diode D2 connects one end of the 8th resistance R8, the other end of the 8th resistance R8 connects one end that the 9th resistance R9 is connected with described 7th resistance R7, one end that 9th resistance R9 is connected with the 7th resistance R7 is connected the grid of the first field effect transistor M1, the drain electrode of the first field effect transistor M1 receives direct voltage, and connect the negative electrode of the 4th diode D4, the source electrode of the first field effect transistor M1 connects the anode of one end and the 4th diode D4 be not connected with the 7th resistance R7 in described 9th resistance R9 respectively, the source electrode of the first field effect transistor M1 is that an output of LLC half-bridge resonance circuit is connected with one end of the primary coil of the second transformer 123, tenth resistance R10 connects with the 12 resistance R12 and is connected between the two ends of second group of primary coil of the first transformer 121, the negative electrode of the 3rd diode D3 connects one end of second group of primary coil of the first transformer 121, the anode of the 3rd diode D3 connects one end of the 11 resistance R11, the other end of the 11 resistance R11 connects one end that the 12 resistance R12 is connected with the tenth resistance R10, one end that 12 resistance R12 is connected with the tenth resistance R10 is connected the grid of the second field effect transistor M2, the drain electrode of the second field effect transistor M2 is connected with the negative electrode of the 5th diode D5 with the source electrode of the first field effect transistor M1 respectively, the source ground of the second field effect transistor M2, and connect the anode of one end and the 5th diode D5 be not connected with the tenth resistance R10 in the 12 resistance R12 respectively, the source electrode of the second field effect transistor D2 connects one end of the second electric capacity C2, the other end of the second electric capacity C2 is connected with the other end of the primary coil of the second transformer 123 as another output of LLC half-bridge resonance circuit.
Further, LED electrical voltage follower circuit as shown in Figure 10, comprises the 6th diode D6, the 7th diode D7 and the 3rd electric capacity C3;
The anode of the 6th diode D6 connects one end of the secondary coil of the second transformer 123, the anode of the 7th diode D7 connects the other end of the secondary coil of the second transformer 123, the negative electrode of the 6th diode D6 is connected with the negative electrode of the 7th diode D7, and connect one end of the 3rd electric capacity C3 and the anode LED+ of LED lamp bar, the other end ground connection of the 3rd electric capacity C3.
Further, tertiary voltage sample circuit as shown in Figure 10, comprises the 13 resistance R13, the 14 resistance R14 and the 4th electric capacity C4;
One end of 13 resistance R13 connects the anode LED+ of LED lamp bar, and the other end of the 13 resistance R13 connects one end of the 14 resistance R14, the other end ground connection of the 14 resistance R14, and the 4th electric capacity C4 is in parallel with the 14 resistance R14; One end connection control circuit that 13 resistance R13 is connected with the 14 resistance R14, exports the first conditioning signal to control circuit, and the voltage proportional of this first conditioning signal is in the voltage of the anode of LED lamp bar.
LLC half-bridge resonance primary circuit is by the first field effect transistor M1 and the second field effect transistor M2 alternate conduction, and the energy of direct voltage is delivered to the secondary of the second transformer 123 by the second transformer 123.Wherein, the resistance and the diode that are connected on the grid of the first field effect transistor M1 can adjust the speed of the rise and fall of the pulse of driving first field effect transistor M1 and absorb some noise jamming; The resistance and the diode that are connected on the grid of the second field effect transistor M2 can adjust the speed of the rise and fall of the pulse of driving second field effect transistor M2 and absorb some noise jamming.Second electric capacity C2 and the second transformer 123 form LLC resonant circuit.This LLC half-bridge resonance primary circuit can realize the resonance of electric capacity and inductance, high-frequency AC signal the power conversion of direct voltage is become to be input to the second transformer 123, and then the control that can realize energy, provide energy by the second transformer 123 to secondary according to the demand of the secondary circuit (secondary circuit of the second transformer) of rear end.LLC half-bridge resonance primary circuit and secondary circuit constitute LLC half-bridge resonance circuit.
If when the dynamic electric voltage feedback circuit that the embodiment of the present invention provides adopts the structure shown in Fig. 2, according to the voltage of each the first voltage sampling circuit be connected with self, the first process chip judges whether that the voltage of the negative terminal of at least one LED lamp bar is zero; If, then generate the second conditioning signal and export described control circuit to, this second conditioning signal is level signal, this second conditioning signal can drag down the voltage that control circuit receives, first control signal of the complementation that control circuit is exported and the frequency of the second control signal raise, thus the voltage of the anode of reduction LED lamp bar is to the driving voltage being less than LED lamp bar, that is, its anode is that the LED lamp bar of this LED lamp bar anode can not be lit; Otherwise, first process chip determines the voltage difference of the sampled value of the negative terminal voltage of each LED lamp bar and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export described control circuit to, this second conditioning signal is level signal; When the setting rule value of the voltage difference determined is in preset range, this second conditioning signal does not change the voltage that control circuit receives, first control signal of the complementation that control circuit is exported and the frequency of the second control signal constant, thus do not change the voltage of the anode of LED lamp bar; When the setting rule value of the voltage difference determined is less than the minimum value of preset range, this second conditioning signal can draw high the voltage that control circuit receives, first control signal of the complementation that control circuit is exported and the frequency of the second control signal reduce, thus raise the voltage of the anode of LED lamp bar; When the setting rule value of the voltage difference determined is greater than the maximum of preset range, this second conditioning signal can drag down the voltage that control circuit receives, first control signal of the complementation that control circuit is exported and the frequency of the second control signal raise, thus reduce the voltage of the anode of LED lamp bar, but this voltage is still higher than the driving voltage of LED lamp bar, that is, its anode is that the LED lamp bar of this LED lamp bar anode still can be lit.
If when the dynamic electric voltage feedback circuit that the embodiment of the present invention provides adopts the structure shown in Fig. 4, the LED lamp bar drive circuit that the embodiment of the present invention provides, as shown in figure 11, according to the voltage from each the second voltage sampling circuit be connected with self, the second process chip 134 judges whether that the voltage of the negative terminal of at least one LED lamp bar is zero, if, then generate the smaller pulse signal of duty, the smaller pulse signal of this duty is through voltage regulator circuit dividing potential drop and export the second conditioning signal after filtering, the now voltage of one end that is connected with the 14 resistance R14 lower than the 13 resistance R13 of the voltage of the second conditioning signal, therefore, the electric current flowing through the 13 resistance R13 understands some by the 14 resistance R14 with flowing to, another part can flow to ground by the second resistance R2 and the 3rd resistance R3, thus the voltage of the one end making the 13 resistance R13 be connected with the 14 resistance R14 reduces, namely the voltage making control circuit receive reduces, first control signal of the complementation that control circuit is exported and the frequency of the second control signal raise, thus the voltage of the anode of reduction LED lamp bar is to the driving voltage being less than LED lamp bar, that is, its anode is that the LED lamp bar of this LED lamp bar anode can not be lit, otherwise, second process chip 134 determines the voltage difference of the sampled value of the negative terminal voltage of each LED lamp bar and the first predeterminated voltage of this LED lamp bar, judge the setting rule value of voltage difference determined whether in preset range, and production burst signal exports described voltage regulator circuit to, when the setting rule value of the voltage difference determined is in preset range, the pulse signal that second process chip 134 generates is through voltage regulator circuit dividing potential drop and the voltage of the second conditioning signal obtained after filtering equals the voltage of one end that the 13 resistance R13 is connected with the 14 resistance R14, therefore, this pulse signal can not change the voltage of one end that the 13 resistance R13 is connected with the 14 resistance R14, namely the voltage that control circuit receives can not be changed, first control signal of this complementation that control circuit is exported and the frequency of the second control signal constant, thus do not change the voltage of the anode of LED lamp bar, when the setting rule value of the voltage difference determined is less than the minimum value of preset range, the duty ratio of pulse signal increases, increasing pulse signal after duty ratio through voltage regulator circuit dividing potential drop exports the second conditioning signal after filtering, the now voltage of one end that is connected with the 14 resistance R14 higher than the 13 resistance R13 of the voltage of the second conditioning signal, therefore, have electric current and flow to ground from the second resistance R2 by the 14 resistance R14, the voltage of this one end that the 13 resistance R13 can be made to be connected with the 14 resistance R14 raises, namely the voltage making control circuit receive raises, thus the frequency of the first control signal of the complementation making control circuit export and the second control signal reduces, thus raise the voltage of the anode of LED lamp bar, when the setting rule value of the voltage difference determined is greater than the maximum of preset range, the duty ratio of pulse signal reduces, reducing pulse signal after duty ratio through voltage regulator circuit dividing potential drop exports the second conditioning signal after filtering, the now voltage of one end that is connected with the 14 resistance R14 lower than the 13 resistance R13 of the voltage of the second conditioning signal, therefore, the electric current flowing through the 13 resistance R13 understands some by the 14 resistance R14 with flowing to, another part can flow to ground by the second resistance R2 and the 3rd resistance R3, thus the voltage of the one end making the 13 resistance R13 be connected with the 14 resistance R14 reduces, namely the voltage making control circuit receive reduces, first control signal of the complementation that control circuit is exported and the frequency of the second control signal raise, thus reduce the voltage of the anode of LED lamp bar, but this voltage is still higher than the driving voltage of LED lamp bar, that is, its anode is that the LED lamp bar of this LED lamp bar anode still can be lit.
A kind of LCD TV that the embodiment of the present invention provides, comprises the LED lamp bar drive circuit that the embodiment of the present invention provides.
Through the above description of the embodiments, those skilled in the art can be well understood to the embodiment of the present invention can by hardware implementing, and the mode that also can add necessary general hardware platform by software realizes.Based on such understanding, the technical scheme of the embodiment of the present invention can embody with the form of software product, it (can be CD-ROM that this software product can be stored in a non-volatile memory medium, USB flash disk, portable hard drive etc.) in, comprise some instructions and perform method described in each embodiment of the present invention in order to make a computer equipment (can be personal computer, server, or the network equipment etc.).
It will be appreciated by those skilled in the art that accompanying drawing is the schematic diagram of a preferred embodiment, the module in accompanying drawing or flow process might not be that enforcement the present invention is necessary.
It will be appreciated by those skilled in the art that the module in the device in embodiment can carry out being distributed in the device of embodiment according to embodiment description, also can carry out respective change and be arranged in the one or more devices being different from the present embodiment.The module of above-described embodiment can merge into a module, also can split into multiple submodule further.
The invention described above embodiment sequence number, just to describing, does not represent the quality of embodiment.
Obviously, those skilled in the art can carry out various change and modification to the present invention and not depart from the spirit and scope of the present invention.Like this, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.
Claims (8)
1. a light-emitting diode light bar drive circuit, is characterized in that, comprises control circuit, driving voltage output circuit and dynamic electric voltage feedback circuit;
Described driving voltage output circuit, for receiving the control signal of described control circuit, under the control of said control signal the direct voltage received be converted into the driving voltage of light-emitting diode and output to the anode of light-emitting diode light bar, and exporting the first conditioning signal to described control circuit, the voltage proportional of described first conditioning signal is in the voltage of the anode of described light-emitting diode light bar;
Described dynamic electric voltage feedback circuit, for the voltage difference of the first predeterminated voltage of the sampled value and this light-emitting diode light bar of determining the negative terminal voltage of each light-emitting diode light bar be connected with self, and generate the second conditioning signal according to the voltage difference determined and export described control circuit to;
Described control circuit, for the second conditioning signal exported according to the first conditioning signal and the described dynamic electric voltage feedback circuit of the second predeterminated voltage, the output of described driving voltage output circuit, generate described control signal and export described driving voltage output circuit to;
Described control circuit specifically for: the second conditioning signal that the first conditioning signal exported according to the second predeterminated voltage, described driving voltage output circuit and described dynamic electric voltage feedback circuit export generates the first control signal and the second control signal, and exports the first control signal and the second control signal to driving voltage output circuit; Described first control signal and described second control signal complementation;
Described driving voltage output circuit comprises the first transformer, LLC half-bridge resonance circuit, the second transformer, light-emitting diode voltage follower circuit and tertiary voltage sample circuit;
Described LLC half-bridge resonance circuit, for receiving described first control signal and described second control signal by described first transformer, and under the control of described first control signal and described second control signal, the direct voltage received is converted to alternating voltage, by resonance, described alternating voltage is exported to described light-emitting diode voltage follower circuit by described second transformer;
Described light-emitting diode voltage follower circuit, the driving voltage for the alternating voltage received being converted to light-emitting diode outputs to the anode of light-emitting diode light bar;
Described tertiary voltage sample circuit, for gathering the voltage that described light-emitting diode voltage follower circuit exports, and export the first conditioning signal to described control circuit, the voltage proportional of described first conditioning signal is in the voltage of the anode of described light-emitting diode light bar.
2. circuit as claimed in claim 1, is characterized in that, described dynamic electric voltage feedback circuit specifically for:
Determine the voltage difference of the sampled value of the negative terminal voltage of each light-emitting diode light bar be connected with self and the first predeterminated voltage of this light-emitting diode light bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export described control circuit to; If the setting rule value of the voltage difference determined is in preset range, then described second conditioning signal is provided for described control circuit and generates the control signal not changing the positive terminal voltage of light-emitting diode light bar; If the setting rule value of the voltage difference determined is less than the minimum value of preset range, then described second conditioning signal is provided for described control circuit and generates the control signal that can improve the positive terminal voltage of light-emitting diode light bar; If the setting rule value of the voltage difference determined is greater than the maximum of preset range, then described second conditioning signal is provided for described control circuit and generates the control signal that can reduce the positive terminal voltage of light-emitting diode light bar;
Wherein, the setting rule value of the voltage difference determined is the mean value of the voltage difference determined or the minimum value of voltage difference determined.
3. circuit as claimed in claim 2, it is characterized in that, dynamic electric voltage feedback circuit is also for before the voltage difference of the sampled value of negative terminal voltage and the first predeterminated voltage of this light-emitting diode light bar of determining each light-emitting diode light bar be connected with self, determine that the negative terminal voltage of at least one light-emitting diode light bar be connected with self equals zero, and generate the second conditioning signal and export described control circuit to, described second conditioning signal is provided for the generation of described control circuit makes the positive terminal voltage of light-emitting diode light bar be less than the control signal of the driving voltage of light-emitting diode light bar.
4. circuit as claimed in claim 3, is characterized in that, dynamic electric voltage feedback circuit specifically comprises the first process chip and at least one first voltage sampling circuit;
Each first voltage sampling circuit, the sampled value for the negative terminal voltage of this light-emitting diode light bar obtained of being sampled by the negative terminal from the light-emitting diode light bar be connected with self exports to the first process chip;
According to the voltage from each the first voltage sampling circuit be connected with self, described first process chip, for judging whether that the voltage of the negative terminal of at least one light-emitting diode light bar is zero; If so, then generate the second conditioning signal and export described control circuit to, described second conditioning signal is provided for the generation of described control circuit makes the positive terminal voltage of light-emitting diode light bar be less than the control signal of the driving voltage of light-emitting diode light bar; Otherwise, determine the voltage difference of the sampled value of the negative terminal voltage of each light-emitting diode light bar and the first predeterminated voltage of this light-emitting diode light bar, judge the setting rule value of voltage difference determined whether in preset range, and generate the second conditioning signal and export described control circuit to; When the setting rule value of the voltage difference determined is in preset range, described second conditioning signal is provided for described control circuit and generates the control signal not changing the positive terminal voltage of light-emitting diode light bar; When the setting rule value of the voltage difference determined is less than the minimum value of preset range, described second conditioning signal is provided for described control circuit and generates the control signal that can improve the positive terminal voltage of light-emitting diode light bar; When the setting rule value of the voltage difference determined is greater than the maximum of preset range, described second conditioning signal is provided for described control circuit and generates the control signal that can reduce the positive terminal voltage of light-emitting diode light bar.
5. circuit as claimed in claim 3, it is characterized in that, dynamic electric voltage feedback circuit specifically comprises the second process chip, voltage regulator circuit and at least one the second voltage sampling circuit;
Each second voltage sampling circuit, the sampled value for the negative terminal voltage of this light-emitting diode light bar obtained of being sampled by the negative terminal from the light-emitting diode light bar be connected with self exports to the second process chip;
According to the voltage from each the second voltage sampling circuit be connected with self, described second process chip, for judging whether that the voltage of the negative terminal of at least one light-emitting diode light bar is zero; If, then production burst signal exports described voltage regulator circuit to, described pulse signal is converted to the second conditioning signal by described voltage regulator circuit, makes the positive terminal voltage of light-emitting diode light bar be less than the control signal of the driving voltage of light-emitting diode light bar for controlling the generation of described control circuit; Otherwise, determine the voltage difference of the sampled value of the negative terminal voltage of each light-emitting diode light bar and the first predeterminated voltage of this light-emitting diode light bar, judge the setting rule value of voltage difference determined whether in preset range, and production burst signal exports described voltage regulator circuit to; When the setting rule value of the voltage difference determined is in preset range, described pulse signal is converted to the second conditioning signal by described voltage regulator circuit, generates for controlling described control circuit the control signal not changing the positive terminal voltage of light-emitting diode light bar; When the setting rule value of the voltage difference determined is less than the minimum value of preset range, described pulse signal is converted to the second conditioning signal by described voltage regulator circuit, generates the control signal that can improve the positive terminal voltage of light-emitting diode light bar for controlling described control circuit; When the setting rule value of the voltage difference determined is greater than the maximum of preset range, described pulse signal is converted to the second conditioning signal by described voltage regulator circuit, generates the control signal that can reduce the positive terminal voltage of light-emitting diode light bar for controlling described control circuit;
Described voltage regulator circuit, for being converted to the second conditioning signal by the pulse signal from described second process chip by filtering and dividing potential drop.
6. circuit as claimed in claim 5, it is characterized in that, described voltage regulator circuit comprises the first resistance, the second resistance, the 3rd resistance and the first electric capacity;
One end of first resistance receives the pulse signal from described second process chip, the other end of the first resistance connects one end of the second resistance, the other end of the second resistance exports the second conditioning signal, 3rd resistance and the first Capacitance parallel connection, one end after parallel connection connects one end that the first resistance is connected with the second resistance, the other end ground connection after parallel connection.
7. circuit as claimed in claim 1, it is characterized in that, described circuit also comprises at least one light-emitting diode constant-current circuit;
Each light-emitting diode constant-current circuit, for determining according to the reference voltage of setting the electric current flowing through the light-emitting diode light bar be connected with self, and controls described current constant.
8. a LCD TV, is characterized in that, comprises the light-emitting diode light bar drive circuit as described in any one of claim 1-7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410004753.XA CN103874288B (en) | 2014-01-06 | 2014-01-06 | A kind of light-emitting diode light bar drive circuit and LCD TV |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410004753.XA CN103874288B (en) | 2014-01-06 | 2014-01-06 | A kind of light-emitting diode light bar drive circuit and LCD TV |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103874288A CN103874288A (en) | 2014-06-18 |
| CN103874288B true CN103874288B (en) | 2016-01-13 |
Family
ID=50912307
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410004753.XA Active CN103874288B (en) | 2014-01-06 | 2014-01-06 | A kind of light-emitting diode light bar drive circuit and LCD TV |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103874288B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106255266B (en) * | 2016-08-23 | 2018-03-13 | 深圳市华星光电技术有限公司 | A kind of drive circuit |
| US10271392B2 (en) | 2017-05-16 | 2019-04-23 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | LLC backlight driving control circuit |
| CN106991978B (en) * | 2017-05-16 | 2020-04-10 | 深圳市华星光电技术有限公司 | Backlight drive control circuit based on LLC |
| CN109151351B (en) * | 2018-09-25 | 2021-06-01 | 深圳创维－Rgb电子有限公司 | Power panel and television |
| CN110430634B (en) * | 2019-07-24 | 2024-06-14 | 深圳市裕明鑫科技有限公司 | LED constant current drive capable of adjusting output current |
| CN113823229A (en) * | 2021-09-03 | 2021-12-21 | 惠州视维新技术有限公司 | Driving circuit, fault detection method thereof, backlight module and display device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103108433A (en) * | 2011-11-14 | 2013-05-15 | 台达电子企业管理（上海）有限公司 | Voltage adjusting circuit and light emitting diode (LED) drive device thereof |
| CN103220865A (en) * | 2013-04-27 | 2013-07-24 | 青岛歌尔声学科技有限公司 | Button-cell-powered LED (Light Emitting Diode) drive circuit and Bluetooth device |
| CN103379692A (en) * | 2012-04-16 | 2013-10-30 | 国钰电子(北海)有限公司 | Light emitting diode drive system and method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI410171B (en) * | 2008-12-12 | 2013-09-21 | Chunghwa Picture Tubes Ltd | Current-balance circuit and backlight module having the same |
-
2014
- 2014-01-06 CN CN201410004753.XA patent/CN103874288B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103108433A (en) * | 2011-11-14 | 2013-05-15 | 台达电子企业管理（上海）有限公司 | Voltage adjusting circuit and light emitting diode (LED) drive device thereof |
| CN103379692A (en) * | 2012-04-16 | 2013-10-30 | 国钰电子(北海)有限公司 | Light emitting diode drive system and method |
| CN103220865A (en) * | 2013-04-27 | 2013-07-24 | 青岛歌尔声学科技有限公司 | Button-cell-powered LED (Light Emitting Diode) drive circuit and Bluetooth device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103874288A (en) | 2014-06-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103874288B (en) | A kind of light-emitting diode light bar drive circuit and LCD TV | |
| CN103052227B (en) | Led driving system | |
| CN107155238B (en) | A kind of multiple-channel output constant current driver circuit for LED and driving method | |
| CN107094329B (en) | LED drive circuit | |
| CN102202449B (en) | LED driving control circuit and method | |
| CN101707831B (en) | LED driving circuit and LED lamp | |
| CN106304492B (en) | double-circuit constant current circuit and power supply device | |
| CN103037597B (en) | Multi-channel LED (Light Emitting Diode) constant current control circuit and LED light source control system | |
| CN103440848A (en) | Backlight driving circuit | |
| CN104902653A (en) | LED constant-voltage dimming power supply and LED lamp dimming system | |
| CN103606354A (en) | LED backlight driving circuit and liquid crystal display | |
| CN107070213A (en) | LED drive circuit and its control method | |
| CN106793253B (en) | A kind of LED linear constant-current drive circuit and LED light device | |
| CN104270874A (en) | Sectional type LED driving circuit | |
| CN204119593U (en) | Realize the single channel BOOST constant-current drive circuit that two-way LED drives | |
| CN102137524A (en) | High-efficiency control method for balance-driving light-emitting diode (LED) | |
| CN105592590A (en) | Constant-power LED driving power supply circuit system | |
| CN203340347U (en) | LED power source suitable for driving electronic ballast | |
| CN104185347A (en) | Adjustable light source system used for color selector and light source brightness adjusting method thereof | |
| CN104936356A (en) | Linear constant-current driving circuit | |
| CN207305003U (en) | Lighting system | |
| CN106991978B (en) | Backlight drive control circuit based on LLC | |
| CN102984849A (en) | Multichannel driving device and lighting device | |
| CN206948663U (en) | A kind of multiple-channel output constant current driver circuit for LED | |
| CN206212336U (en) | A kind of LED drive circuit and drive device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 266100 Zhuzhou Road, Laoshan District, Shandong, No. 151, No. Patentee after: Hisense Visual Technology Co., Ltd. Address before: 266100 Zhuzhou Road, Laoshan District, Shandong, No. 151, No. Patentee before: QINGDAO HISENSE ELECTRONICS Co.,Ltd. |