CN106549588A - The power circuit and television set of television set - Google Patents
The power circuit and television set of television set Download PDFInfo
- Publication number
- CN106549588A CN106549588A CN201611128654.8A CN201611128654A CN106549588A CN 106549588 A CN106549588 A CN 106549588A CN 201611128654 A CN201611128654 A CN 201611128654A CN 106549588 A CN106549588 A CN 106549588A
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- China
- Prior art keywords
- input
- voltage
- circuit module
- television set
- flyback pfc
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
- H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
- H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/21—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/217—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
- H02M1/4208—Arrangements for improving power factor of AC input
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The invention discloses a kind of power circuit of television set, the power circuit of the television set includes ac power input end, current rectifying and wave filtering circuit module, the first flyback pfc circuit module and the second flyback pfc circuit module；Ac power input end, for input ac power；Current rectifying and wave filtering circuit module, the AC power for being input into ac power input end carry out rectifying and wave-filtering, and output one exchanges steamed bun ripple power supply signal to the first flyback pfc circuit module；First flyback pfc circuit module, the exchange steamed bun ripple power supply signal for exporting to current rectifying and wave filtering circuit module carry out the control of flyback PFC, while the movement for television set is powered；The second flyback pfc circuit module, for carrying out the control of flyback PFC to exchanging steamed bun ripple power supply signal, while the backlight LED light string for television set provides corresponding supply voltage.The invention also discloses a kind of television set.The power circuit of television set of the present invention has the advantages that efficiency high and low cost.
Description
Technical field
The present invention relates to field of television, more particularly to a kind of power circuit and television set of television set.
Background technology
The power supply of television set (such as LCD colour television sets) needs to provide supply voltage to the movement of television set, meanwhile, to also
Supply voltage is provided to the backlight LED drive board of television set, this supply voltage is converted to backlight LED light by backlight LED drive board
Voltage needed for string, then adjusts LED string electric current by controlling LB voltages again, and then realizes adjusting backlight LED light string
The purpose of brightness.In prior art, the backlight LED light string of LCD colour television sets is generally divided into two kinds of straight-down negative and side entering type.Its
In, the rated operational current scope of the backlight LED light string of side entering type is 80mA-150mA, the volume of the backlight LED light string of straight-down negative
It is 250mA-330mA to determine current margin, if LB female contacts are bad, during open circuit, voltage rises, when on socket Rapid contact
When, because capacitive accumulation high pressure is directly added into LB two ends, the electric current for easily causing backlight LED light string exceedes above-mentioned rated current scope
Higher limit it is too many, backlight LED light string will be easy to be burned out.Therefore, the power circuit of television set allows for realizing right
The function of the overvoltage protection of backlight LED light string.
For now widely used intelligent 4k LCD TVs, its movement and the commonly required power of display screen driving plate are about
For 30W, and required according to national EMC current harmonics eliminations, for the television set more than 75W, its power circuit must all increase
PFC correcting circuits, are had undesirable effect to electrical network with the harmonic wave for avoiding television set.Therefore, when the backlight LED light string of television set
When power is more than 45W, its power circuit is required for increasing PFC correcting circuits.And the backlight of 40-55 cun of LCD colour television sets
The power of LED string is typically greater than 45W, therefore, the power circuit of 40-55 cun of LCD colour television sets must all increase PFC
Correcting circuit, and the cost of components and parts needed for an independent PFC correcting circuit is typically between 8RMB-15RMB, price compared with
It is expensive；And as PFC correcting circuits typically contain more than 30 components and parts, therefore cause the reliability of television power circuit relatively low.
In prior art, television set generally adopts following two power source designs：
(1) 220Vac AC-input voltage rectifying and wave-filterings are changed into by the power panel of television set through pfc circuit
The DC voltage of 400V or so；The backlight power supply voltage of 24V or 60V or so all the way is provided to TV using flyback or LLC circuits
The backlight LED drive board of machine, while, there is provided the movement of the supply voltage of 12V or 24V to television set and display screen drive all the way
Plate.Backlight LED drive board is provided with a backlight control integrated circuit, and the backlight control integrated circuit is by the power panel of television set
The backlight power supply voltage of the 24V for being provided or 60V or so carries out boost boosting rectifier controls, by the 24V or 60V of power panel offer
Voltage rises to the ignition voltage required for backlight LED light string；Also, one is additionally provided with the backlight LED drive board of television set solely
Vertical constant-current control circuit, the constant-current control circuit realize the current control gone here and there to 1 to 4 string backlight LED light strings；
(2) power panel and backlight LED drive board of 40-55 cun of television set unites two into one, and ac power input end is input into
AC power Jing PFC correcting circuits be transformed to the power supply of 400V, the power supply of the 400V is by flyback DC_DC electricity independent all the way
Road, movement and display screen of the flyback DC_DC circuit by the Power convert of 400V for the supply voltage to television set of 12V or 24V are driven
Dynamic plate；The power supply of the above-mentioned 400V is also through the conversion of a LLC quasi-resonance circuits, there is provided -4 string backlight LED light string difference of 1 string is bright
Supply voltage (or even the supply voltage needed for -8 string backlight LED light string of 4 string) needed for degree.However, due to LED diodes it is peculiar
C-V characteristic, when output current is bigger, its turn-on voltage is also bigger, therefore, in the power source design of television set, its electricity
The output voltage of the PFC correcting circuits in source plate is generally 400V or so and (generally defines the input electricity of LLC quasi-resonance circuits
Pressure), simultaneously because the narrower characteristic of the intrinsic gain ranging of LLC quasi-resonance circuits, therefore, when mixing to backlight LED light string
When closing light modulation, the power source design has higher management and control requirement to the range of voltage values of backlight LED light string.
The existing above two power source design of television set, as its power panel all employs PFC correcting circuits, therefore TV
The above two power source design of machine all haves the shortcomings that high cost and reliability are low；Also, above-mentioned power source design (two) is to backlight
The range of voltage values of LED string also has higher management and control to require.
The content of the invention
Present invention is primarily targeted at providing a kind of power circuit of television set, it is intended to reduce television power circuit
The reliability of cost and raising television power circuit.
To achieve these goals, the present invention provides a kind of power circuit of television set, the power circuit of the television set
Include ac power input end, current rectifying and wave filtering circuit module, the first flyback pfc circuit mould including the power circuit of the television set
Block and the second flyback pfc circuit module；Wherein：
The ac power input end, for input ac power；
The current rectifying and wave filtering circuit module, it is whole for carrying out to the AC power that the ac power input end is input into
Stream filtering, output one exchange steamed bun ripple power supply signal to the first flyback pfc circuit module；
The first flyback pfc circuit module, for carrying out the control of flyback PFC to the exchange steamed bun ripple power supply signal,
Movement for television set is powered；
The second flyback pfc circuit module, for the exchange steamed bun exported to the current rectifying and wave filtering circuit module
Ripple power supply signal carries out the control of flyback PFC, and the backlight LED light string for television set provides corresponding supply voltage, described to control
The brightness of backlight LED light string.
Preferably, the input of the current rectifying and wave filtering circuit module is connected with the ac input end, the rectifying and wave-filtering
The output end of circuit module input and the second flyback pfc circuit mould respectively with the first flyback pfc circuit module
The input connection of block；The output end of the first flyback pfc circuit module is connected with the power end of the movement of television set；It is described
The output end of the second flyback pfc circuit module is connect with the backlight LED light series winding of television set.
Preferably, the first flyback pfc circuit module includes the first transformer unit, the first input voltage measurement list
Unit, output voltage feedback detector unit and the first flyback PFC main control unit；Wherein：
First transformer unit, for carrying out voltage change to the voltage of the output end of the current rectifying and wave filtering circuit module
Change；
The first input voltage measurement unit, for carrying out to the voltage of the output end of the current rectifying and wave filtering circuit module
Detection；
The output voltage feeds back detector unit, for the voltage of the output end to the first flyback pfc circuit module
Carry out feedback detection；
The first flyback PFC main control unit, for the electricity according to detected by the first input voltage measurement unit
Pressure and the fed back voltage for detecting of output voltage feedback detector unit, control the first transformer unit output corresponding
Voltage to television set movement.
Preferably, the first flyback pfc circuit module also includes the first output rectification filter unit；First output
Rectification filtering unit, for carrying out rectifying and wave-filtering to the voltage that first transformer unit is exported, and by after rectifying and wave-filtering
The movement of voltage output to television set, is that the movement of television set is powered.
Preferably, the output end of the input of the first input voltage measurement unit and the current rectifying and wave filtering circuit module
Connection, the output end of the first input voltage measurement unit are connected with the detection input of the first flyback PFC main control unit
Connect；The input of the output voltage feedback detector unit is connected with the output end of the first flyback pfc circuit module, described
The output end of output voltage feedback detector unit is connected with the feedback input end of the first flyback PFC main control unit；Described
The control output end of one flyback PFC main control unit is connected with the primary coil of first transformer unit；First transformation
Described in the secondary coil Jing of device unit, the first output rectification filter unit is connected with the movement of television set.
Preferably, the second flyback pfc circuit module includes the second transformer unit, the second input voltage measurement list
Unit, simulation dimming control signal input, digital dimming control signal input, backlight LED light modulation feedback control unit, overvoltage
Protection feedback control unit and the second flyback PFC main control unit；Wherein：
Second transformer unit, for carrying out voltage change to the voltage of the output end of the current rectifying and wave filtering circuit module
Change；
The second input voltage measurement unit, for carrying out to the voltage of the output end of the current rectifying and wave filtering circuit module
Detection；
The simulation dimming control signal input, for being input into simulation dimming control signal；
The digital dimming control signal input, for being input into digital dimming control signal
Backlight LED dims feedback control unit, for carrying out feedback inspection to the electric current of the backlight LED light string of television set
Survey, and the backlight detected according to the simulation dimming control signal or the digital dimming control signal and feedback
The electric current of LED string, the corresponding light modulation feedback control signal of output is to the second flyback PFC main control unit；
The overvoltage protection feedback control unit, for carrying out to the current voltage of the backlight LED light string positive pole of television set
Detection, and when the current voltage of the backlight LED light string positive pole is too high, export corresponding overvoltage protection feedback control signal extremely
The second flyback PFC main control unit；
The second flyback PFC main control unit, for defeated according to detected by the second input voltage measurement unit
Enter voltage and the light modulation feedback control signal, control second transformer unit and corresponding voltage is exported to the backlight
LED string, the brightness to the backlight LED light string are adjusted；And examined according to the second input voltage measurement unit
The input voltage for measuring and the overvoltage protection feedback control signal, control second transformer unit and export corresponding voltage
To the backlight LED light string, overvoltage protection is carried out to the backlight LED light string.
Preferably, the second flyback pfc circuit module also includes the second output rectification filter unit, second output
Rectification filtering unit, for carrying out rectifying and wave-filtering to the voltage that second transformer unit is exported, and by after rectifying and wave-filtering
The backlight LED light string of voltage output to television set, is the backlight LED light statements based on collusion electricity.
Preferably, the output end of the input of the second input voltage measurement unit and the current rectifying and wave filtering circuit module
Connection, output end are connected with the detection input of the second flyback PFC main control unit；
The first input end of the backlight LED light modulation feedback control unit is connect with backlight LED light series winding, the second input
End is connected with the simulation dimming control signal input, and the 3rd input is connected with the digital dimming control signal input
Connect, output end is connected with the feedback input end of the second flyback PFC main control unit；
The input of the overvoltage protection feedback control unit is connected with the positive pole of the backlight LED light string, output end with
The feedback input end connection of the second flyback PFC main control unit；
The control output end of the second flyback PFC main control unit is connected with the primary coil of second transformer unit
Connect；Described in the secondary coil Jing of second transformer unit, the second output rectification filter unit is contacted with the backlight LED light
Connect.
Additionally, to achieve these goals, the present invention also provides a kind of television set, and the television set includes as above
The power circuit of television set.
The present invention provides a kind of power circuit of television set, and the power circuit of the television set includes the power supply of the television set
Circuit includes ac power input end, current rectifying and wave filtering circuit module and the first flyback pfc circuit module；The AC power input
End, for input ac power；The current rectifying and wave filtering circuit module, for the friendship being input into the ac power input end
Stream power supply carries out rectifying and wave-filtering, and output one exchanges steamed bun ripple power supply signal to the first flyback pfc circuit module；Described first
Flyback pfc circuit module, for carrying out the control of flyback PFC to the exchange steamed bun ripple power supply signal, is that the movement of television set is supplied
Electricity；Second flyback pfc circuit module, for carrying out the control of flyback PFC to exchanging steamed bun ripple power supply signal, is the backlight of television set
LED string provides corresponding supply voltage.The power circuit of television set of the present invention, relative to the power supply of television set in prior art
Circuit, reduces conventional independent PFC correcting circuits module, so as to reduce cost；Meanwhile, the power supply electricity of television set of the present invention
Road also has the advantages that few circuit function module, simple circuit and efficiency high, and also reducing the voltage management and control to LED string will
Ask.
Description of the drawings
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
Accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this
Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, can be with
Structure according to these accompanying drawings obtains other accompanying drawings.
Fig. 1 is the modular structure schematic diagram of one embodiment of power circuit of television set of the present invention；
Fig. 2 be television set of the present invention one embodiment of power circuit in the cellular construction of the first flyback pfc circuit module show
It is intended to；
Fig. 3 be television set of the present invention one embodiment of power circuit in the cellular construction of the second flyback pfc circuit module show
It is intended to；
Fig. 4 be television set of the present invention one embodiment of power circuit in the circuit structure of the first flyback pfc circuit module show
It is intended to；
Fig. 5 be television set of the present invention one embodiment of power circuit in the circuit structure of the second flyback pfc circuit module show
It is intended to.
The realization of the object of the invention, functional characteristics and advantage will be described further in conjunction with the embodiments referring to the drawings.
Specific embodiment
It should be appreciated that specific embodiment described herein is not intended to limit the present invention only to explain the present invention.
The present invention provides a kind of power circuit of television set, and with reference to Fig. 1, Fig. 1 is the power circuit one of television set of the present invention
The modular structure schematic diagram of embodiment, in the present embodiment, the power circuit of the television set includes ac power input end 101, whole
Stream filter circuit module 102, the first flyback pfc circuit module 103 and the second flyback pfc circuit module 104.
Wherein, the ac power input end 101, for input ac power, i.e., described ac power input end 101 is defeated
Alternating current of the power supply for entering for the 220V of 50HZ；
The current rectifying and wave filtering circuit module 102, for the AC power being input into the ac power input end 101
Carry out rectifying and wave-filtering, output one exchanges steamed bun ripple power supply signal to the first flyback pfc circuit module 103 and described second anti-
Sharp pfc circuit module 104.In the present embodiment, the current rectifying and wave filtering circuit module 102 exports the exchange steamed bun ripple power supply of 100HZ
Signal Uin is to the first flyback pfc circuit module 103 and the second flyback pfc circuit module 104；
The first flyback pfc circuit module 103, for the exchange steamed bun exported to the current rectifying and wave filtering circuit module 102
Bow wave power supply signal Uin carries out the control of flyback PFC, is that the movement 200 of television set provides supply voltage Uout1；
The second flyback pfc circuit module 104：For the friendship exported to the current rectifying and wave filtering circuit module 102
Stream steamed bun ripple power supply signal Uin carries out the control of flyback PFC, is that the backlight LED lamp string 300 of television set provides corresponding power supply electricity
Pressure Uout2, to control the brightness of the backlight LED light string 300 in television set.
Specifically, in the present embodiment, input and the ac input end 101 of the current rectifying and wave filtering circuit module 102
Connection, the output end of the current rectifying and wave filtering circuit module 102 input respectively with the first flyback pfc circuit module 103
Connect with the input of the second flyback pfc circuit module 104；The output end of the first flyback pfc circuit module 103 with
The power end connection of the movement 200 of television set；The output end of the second flyback pfc circuit module 104 and the backlight of television set
LED string 300 connects.
Fig. 2 be television set of the present invention one embodiment of power circuit in the cellular construction of the first flyback pfc circuit module show
It is intended to, sees figures.1.and.2 in the lump, in the present embodiment, the first flyback pfc circuit module 103 includes the first transformer unit
1031st, the first input voltage measurement unit 1032, output voltage feedback detector unit 1033, the first flyback PFC main control unit
1034 and the first output rectification filter unit 1035.
Wherein, in the present embodiment, first transformer unit 1031, for the current rectifying and wave filtering circuit module 102
The voltage Uin of output end carry out voltage transformation；
The first input voltage measurement unit 1032, for the output end to the current rectifying and wave filtering circuit module 102
Voltage Uin is detected；
The output voltage feeds back detector unit 1033, for the output end to the first flyback pfc circuit module 103
Voltage Uout1 carry out feedback detection；
The first flyback PFC main control unit 1034, for being examined according to the first input voltage measurement unit 1032
The voltage for measuring and the fed back voltage for detecting of output voltage feedback detector unit 1033, control first transformer
Unit 1031 exports the movement 200 of corresponding voltage to television set；
The first output rectification filter unit 1035, for entering to the voltage that first transformer unit 1031 is exported
Row rectifying and wave-filtering, and by the movement 200 of the voltage output after rectifying and wave-filtering to television set, be that the movement 200 of television set is powered.
Specifically, in the present embodiment, the input and the rectifying and wave-filtering of the first input voltage measurement unit 1032
The output end connection of circuit module 102, output end and first flyback PFC of the first input voltage measurement unit 1032
The detection input connection of main control unit 1034；The input of the output voltage feedback detector unit 1033 is anti-with described first
The output end connection of sharp pfc circuit module 103, the output end of the output voltage feedback detector unit 1033 are anti-with described first
The feedback input end connection of sharp PFC main control units 1034；The control output end of the first flyback PFC main control unit 1034 and institute
State the primary coil (not shown) connection of the first transformer unit 1031；The secondary coil of first transformer unit 1031
Described in (not shown) Jing, the first output rectification filter unit 1035 is connected with the movement 200 of television set.
Fig. 3 be television set of the present invention one embodiment of power circuit in the cellular construction of the second flyback pfc circuit module show
It is intended to, in the lump with reference to Fig. 1 and Fig. 3, in the present embodiment, the second flyback pfc circuit module 104 includes the second transformer unit
1041st, the second input voltage measurement unit 1042, input 1043, the digital dimming control signal input of simulation dimming control signal
End 1044, backlight LED light modulation feedback control unit 1045, overvoltage protection feedback control unit 1046, the second flyback PFC master control list
Unit 1047 and the second output rectification filter unit 1048.
Wherein, in the present embodiment, second transformer unit 1041：For to the current rectifying and wave filtering circuit module 102
The voltage Uin of output end carry out voltage transformation；
The second input voltage measurement unit 1042：For the output end to the current rectifying and wave filtering circuit module 102
Voltage Uin is detected；
The simulation dimming control signal input 1043：For being input into simulation dimming control signal；
The digital dimming control signal input 1044：For being input into digital dimming control signal
Backlight LED dims feedback control unit 1045, for entering to the electric current of the backlight LED light string 300 of television set
Row feedback detection, and the simulation dimming control signal according to 1043 input of simulation dimming control signal input or institute
State the back of the body that the digital dimming control signal and feedback of the input of digital dimming control signal input 1044 are detected
The electric current of light LED string 300, the corresponding light modulation feedback control signal of output is to the second flyback PFC main control unit 1047；
The overvoltage protection feedback control unit 1046：For the backlight LED light string 300 to television set positive pole it is current
Voltage is detected, and when the current voltage of the positive pole of the backlight LED light string 300 is too high, exports corresponding overvoltage protection
Feedback control signal is to the second flyback PFC main control unit 1047；
The second flyback PFC main control unit 1047：For being examined according to the second input voltage measurement unit 1042
The input voltage for measuring and the light modulation feedback control signal of the backlight LED light modulation output of feedback control unit 1045, control
Make second transformer unit 1041 and corresponding voltage is exported to the backlight LED light string 300, to the backlight LED light string
300 brightness is adjusted；And the input voltage according to detected by the second input voltage measurement unit 1042 and institute
The overvoltage protection feedback control signal of the output of overvoltage protection feedback control unit 1046 is stated, the second transformer list is controlled
The corresponding voltage of 1041 output of unit carries out overvoltage protection to the backlight LED light string 300 to the backlight LED light string 300；
The second output rectification filter unit 1048：For entering to the voltage that second transformer unit 1041 is exported
Row rectifying and wave-filtering, and by the backlight LED light string 300 of the voltage output after rectifying and wave-filtering to television set, be the backlight LED light string
300 power supplies (voltage often gone here and there needed for backlight LED light string is generally below 200V).
Specifically, in the lump with reference to Fig. 1 and Fig. 3, in the present embodiment, the input of the second input voltage measurement unit 1042
End is connected with the output end of the current rectifying and wave filtering circuit module 102, the output end of the second input voltage measurement unit 1042
It is connected with the detection input of the second flyback PFC main control unit 1047；Backlight LED dims feedback control unit 1045
First input end be connected with the backlight LED light string 300, the second of backlight LED light modulation feedback control unit 1045 is defeated
Enter end to be connected with the simulation dimming control signal input 1043, the of the backlight LED light modulation feedback control unit 1045
Three inputs are connected with the digital dimming control signal input 1044, and backlight LED dims feedback control unit 1045
Output end be connected with the feedback input end of the second flyback PFC main control unit 1047；The overvoltage protection feedback control list
Unit 1046 input be connected with the positive pole of the backlight LED light string 300, the overvoltage protection feedback control unit 1046 it is defeated
Go out end to be connected with the feedback input end of the second flyback PFC main control unit 1047；The second flyback PFC main control unit 1047
Control output end be connected with the primary coil of second transformer unit 1041；Second transformer unit 1041 time
Second output rectification filter unit 1048 described in level coil Jing is connected with the backlight LED light string 300.
Fig. 4 be television set of the present invention one embodiment of power circuit in the circuit structure of the first flyback pfc circuit module show
It is intended to, in the lump with reference to Fig. 1, Fig. 2 and Fig. 4, in the present embodiment, described first in the first flyback pfc circuit module 103 becomes
Depressor unit 1031 includes flyback transformer TX1 and inductance LP1, wherein, the flyback transformer TX1 include primary coil S1,
Secondary coil S2 and secondary coil S3.Specifically, the first end of the primary coil S1 of the flyback transformer TX1 and the rectification
The output end connection of filter circuit module 102, second end of the primary coil S1 of the flyback transformer TX1 are anti-with described first
The control output end connection of sharp PFC main control units 1034；The first end of the inductance LP1 is first with the flyback transformer TX1
The first end connection of level coil S1, second end of the inductance LP1 and the second of the primary coil S1 of the flyback transformer TX1
End connection；The first end of the secondary coil S2 of the flyback transformer TX1 and the first output rectification filter unit 1035
Input connects, the second end ground connection of the secondary coil S2 of the flyback transformer TX1；The secondary of the flyback transformer TX1
The first end ground connection of coil S3；Second end of the secondary coil S3 of the flyback transformer TX1 is the first flyback PFC master control
Unit 1034 provides operating voltage, and specifically, second end of the secondary coil S3 of the flyback transformer TX1 is with diode D3's
Anode connects, and the negative electrode of diode D3 is connected with the first end of the resistance R10, second end of the resistance R10 and described the
One flyback PFC main control unit 1034 connects.
The first input voltage measurement unit 1032 in the present embodiment, in the first flyback pfc circuit module 103
Including resistance R1, resistance R2, resistance R3 and resistance R4.Specifically, the first end of the resistance R1 and the current rectifying and wave filtering circuit
The output end connection of module 102, second end of resistance R1 first end and first flyback respectively with the resistance R2
The first detection input connection of PFC main control units 1034, the second end ground connection of the resistance R2；The first end of the resistance R3
Be connected with the output end of the current rectifying and wave filtering circuit module 102, second end of the resistance R3 respectively with the resistance R4
The second detection input connection of one end and the first flyback PFC main control unit 1034, the second end ground connection of the resistance R4.
The output voltage feedback detector unit 1033 in the present embodiment, in the first flyback pfc circuit module 103
Including resistance R5, resistance R6, resistance R7, resistance R8, resistance R9, electric capacity C1, precision voltage regulator ZD1 and optocoupler U1.Specifically, institute
State output end (namely first output rectification filter of the first end of resistance R5 and the first flyback pfc circuit module 103
The output end of unit 1035) connection, second end of resistance R5 first end respectively with the resistance R6, the resistance R7
The control end connection of first end and the precision voltage regulator ZD1；The second end ground connection of the resistance R6；The second of the resistance R7
Electric capacity C1 described in the Jing of end is connected with the first end of the negative electrode and the resistance R8 of the precision voltage regulator ZD1 respectively；The precision
The plus earth of source of stable pressure ZD1；The second end ground connection of the resistance R6；Second end of the resistance R8 respectively with the optocoupler U1
In light emitting diode anode and the resistance R9 first end connection；Second end of the resistance R9 and the described first output
Rectification filtering unit 1035 connects；The negative electrode of the negative electrode of the light emitting diode in the optocoupler U1 and the precision voltage regulator ZD1
Connection, the colelctor electrode of the triode in the optocoupler U1 are connected with the feedback input end of the first flyback PFC main control unit 1034
Connect, the grounded emitter of the triode in the optocoupler U1.
The first flyback PFC main control unit 1034 in the present embodiment, in the first flyback pfc circuit module 103
Including flyback PFC chip U2, electric capacity C2, electric capacity C3, electric capacity C4, resistance R11, resistance R12, PMOS QS1 and fly-wheel diode
D1.Specifically, exchange detection input pin AC (namely the first flyback pfc circuit modules 103 of the flyback PFC chip U2
The first detection input) be connected with second end of the resistance R1, the detection of the input voltage waveform of the flyback PFC chip U2
Second end of pin VFF (namely second detection input of the first flyback pfc circuit module 103) and the resistance R3 connects
Connect, the grounding leg GND of flyback PFC chip U2 ground connection, the current detecting pin CS of the flyback PFC chip U2 respectively with it is described
The first end of electric capacity C3 and the resistance R11 first end connection, the high voltage startup pin HV of the flyback PFC chip U2 with it is described
The output end connection of current rectifying and wave filtering circuit module 102, operating voltage input pin VCC and the electricity of the flyback PFC chip U2
The connection of the second ends of resistance R10, electric capacity C4 ground connection, the flyback PFC core described in the feed back input pin FB Jing of the flyback PFC chip U2
The feed back input pin FB of piece U2 also feeds back the triode in the optocoupler U1 in detector unit 1033 with the output voltage
Colelctor electrode connection (the feed back input pin FB of the flyback PFC chip U2 namely the first flyback PFC main control unit 1034 it is anti-
Feedback input), the driving output pin DRV of the flyback PFC chip U2 is connected with the grid of PMOS QS1；The electric capacity
The second end ground connection of C3；The first end of the electric capacity C2 is connected with the operating voltage input pin VCC of the flyback PFC chip U2,
The second end ground connection of the electric capacity C2；The first end of resistance R12 drain electrode and the resistance respectively with PMOS QS1
The second end connection of R11, the second end ground connection of the resistance R12；The source electrode of PMOS QS1 respectively with two pole of the afterflow
The second end connection of the anode of pipe D1 and the inductance LP1, the source electrode of PMOS QS1 namely the first flyback PFC master
The control output end of control unit 1034；The primary coil S1 of the negative electrode of the sustained diode 1 and the flyback transformer TX1
First end connection.
The first output rectification filter unit 1035 in the present embodiment, in the first flyback pfc circuit module 103
Including diode D2, inductance L1, electric capacity C5 and electric capacity C6.Specifically, the anode of the diode D2 is that the described first output is whole
The input of stream filter unit 1035, the of the anode of the diode D2 and the secondary coil S2 of the flyback transformer TX1
One end connects, and the negative electrode of the diode D2 is connected with the first end of the inductance L1, second end of the inductance L1 and TV
The movement 200 of machine connects, and second end of the inductance L1 is the output end of the first output rectification filter unit 1035, described
The output end of the first output rectification filter unit 1035 is connected the (confession needed for the movement 200 of television set with the movement 200 of television set
Piezoelectric voltage is generally 12V or 24V)；The first end of the electric capacity C5 is connected with the negative electrode of the diode D2, the electric capacity C5's
Second end is connected with the first end of the electric capacity C6；Second end of the electric capacity C6 is connected with second end of the inductance L1.
In the lump with reference to Fig. 1, Fig. 2 and Fig. 4, in the present embodiment, the current rectifying and wave filtering circuit module 102 is by the AC power
The AC power of the 50HZ is input into by input 101 is changed into the exchange steamed bun ripple signal of 100HZ；The first flyback PFC electricity
The first input voltage measurement unit 1032 (i.e. described resistance R1, resistance R2, resistance R3 and resistance R4) in road module 103
Exchange steamed bun ripple signal (also referred to as described first flyback PFC electricity to the 100HZ of the current rectifying and wave filtering circuit module 102 output
The input voltage of road module 103) magnitude of voltage and voltage waveform detected respectively；The first flyback pfc circuit module 103
In output voltage feedback detector unit 1033 in the resistance R5 and resistance R6 to the first flyback pfc circuit mould
The output voltage of the output end of block 103 carries out feedback detection, the mistake of precision voltage regulator ZD1 described in the fed back voltage Jing for detecting
Difference is amplified, then Jing optocoupler U1 feed back to the feed back input of the flyback PFC chip U2 in the first flyback PFC main control unit 1034
Pin FB, the flyback PFC chip U2 are by the voltage detected by the first input voltage measurement unit 1032 and the output
The fed back voltage for detecting of Voltage Feedback detector unit 1033 carries out the computing of complexity, the driving of the flyback PFC chip U2
Grids of the output pin DRV by the drive control signal to PMOS QS1 of output different duty, to control the PMOS
Pipe QS1's is turned on and off the time, the electric current of PMOS QS1 is changed with the change of the exchange steamed bun ripple signal of input
(as adopted critical current pattern), so as to realize the purpose of PFC corrections；Meanwhile, become by the voltage of the flyback transformer TX1
Change, after the rectification of the diode D2 in the first output rectification filter unit 1035 described in Jing and the filtering of electric capacity C5, then Jing
The LC filtering of inductance L1 and electric capacity C6, filters part high-frequency interferencing signal, there is provided supply to the direct current needed for the movement 200 of television set
Piezoelectric voltage.
Fig. 5 be television set of the present invention one embodiment of power circuit in the circuit structure of the second flyback pfc circuit module show
It is intended to, in the lump with reference to Fig. 1, Fig. 3 and Fig. 5, in the present embodiment, described second in the second flyback pfc circuit module 104 becomes
Depressor unit 1041 includes flyback transformer TX2 and inductance LP2, wherein, the flyback transformer TX2 include primary coil S4,
Secondary coil S5, secondary coil S6 and secondary coil S7.Specifically, the Same Name of Ends of the primary coil S4 of the transformer TX2 with
The output end connection of the current rectifying and wave filtering circuit module 102, the different name end of the primary coil S4 of the transformer TX2 and described the
The control output end connection of two flyback PFC main control units 1047；The first end of the inductance LP2 is first with the transformer TX2
The Same Name of Ends connection of level coil S4, second end of the inductance LP2 is connected with the different name end of the primary coil S4 of the transformer TX2
Connect；The Same Name of Ends of the secondary coil S5 of the transformer TX2 is connected with the second output rectification filter unit 1048, the change
The different name end ground connection of the secondary coil S5 of depressor TX2；The different name end ground connection of the secondary coil S6 of the transformer TX2；The change
The Same Name of Ends of the secondary coil S6 of depressor TX2 is connected with the second output rectification filter unit 1048；The flyback transformer
The Same Name of Ends of the secondary coil S7 of TX2 is that the second flyback PFC main control unit 1047 provides operating voltage, specifically, described
The Same Name of Ends Jing resistance R34s of the secondary coil S7 of transformer TX2 are connected with the anode of diode D6, the negative electrode of diode D6 and institute
State the second flyback PFC main control unit 1047 to connect.
The second input voltage measurement unit 1042 in the present embodiment, in the second flyback pfc circuit module 104
Including resistance R13, resistance R14, resistance R15 and resistance R16.Specifically, the first end of the resistance R13 and the rectifying and wave-filtering
The output end connection of circuit module 102, second end of the resistance R13 respectively with the first end of the resistance R14 and described the
The first detection input connection of two flyback PFC main control units 1047, the second end ground connection of the resistance R14；The resistance R15
First end be connected with the output end of the current rectifying and wave filtering circuit module 102, second end of the resistance R15 respectively with the electricity
The second detection input connection of the first end and the second flyback PFC main control unit 1047 of resistance R16, the resistance R16's
Second end is grounded.
In the present embodiment, the backlight LED light string 300 includes the first backlight LED light string 301 and the first backlight LED light string
LED2, wherein, the first backlight LED light string 301 and the second backlight LED light string 302 are connected in series with each other.
The backlight LED light modulation feedback control unit in the present embodiment, in the second flyback pfc circuit module 104
1045 include resistance R17, resistance R18, resistance R19, resistance R20, resistance R21, resistance R22, resistance R23, resistance R24, resistance
R25, resistance R26, resistance R27, resistance R28, resistance R29, NPN triode Q1, NPN triode Q2, NPN triode Q3, first
Voltage comparator U4, second voltage comparator U5, electric capacity C7, electric capacity C8, electric capacity C13, electric capacity C14, diode D7, two pole of voltage stabilizing
Pipe ZD2, optocoupler U3 and optocoupler U6.Specifically, the anode of the light emitting diode in the optocoupler U3 and first backlight LED light
The negative pole connection of string 301, the positive pole of the negative electrode of the light emitting diode in the optocoupler U3 and the second backlight LED light string 302
Connection, the colelctor electrode Jing resistance R17 ground connection of triode, the emitter stage Jing resistance of triode in the optocoupler U3 in the optocoupler U3
R18 is connected with the negative pole of the second backlight LED light string 302；The positive pole and described second of the first backlight LED light string 301
The output end connection of output rectification filter unit 1048；In the optocoupler U3 colelctor electrode of triode also Jing resistance R19 respectively with
The in-phase input end connection of the first end of resistance R20 and the first voltage comparator U4, second end of the resistance R20 and institute
State overvoltage protection feedback control unit 1046 to connect；The first end of resistance R21 and the simulation dimming control signal input
1043 (i.e. ADIM ends) connect, and second end of resistance R21 is connected with the in-phase input end of the first voltage comparator U4；Resistance
The first end of R22 is connected with the anode of the Zener diode ZD2, and the first end of resistance R22 is also grounded, and the second of resistance R21
End is connected with the inverting input of the first voltage comparator U4；The output end and diode of the first voltage comparator U4
The negative electrode connection of D7, the power positive end of first voltage comparator U4 are connected with the emitter stage of NPN triode Q3；Described first
Electric capacity C14 is also associated between the inverting input and normal phase input end of voltage comparator U4；The current collection of NPN triode Q3
Pole is connected with the output end of the second output rectification filter unit 1048, the base stage of NPN triode Q3 respectively with it is described
The first end connection of the first end of cathode capacitance C13 of Zener diode ZD2 and the resistance R25；The second of the electric capacity C13
End is connected with the anode of the Zener diode ZD2；The collection of second end of the resistance R25 and NPN triode Q3
Electrode connects；The first end of the electric capacity C7 is connected with the output end of the first voltage comparator U4, and the of the electric capacity C7
Two end Jing resistance R26 are connected with the inverting input of the first voltage comparator U4；The first end of resistance R24 and the numeral
Dimming control signal input 1044 (i.e. PDIM ends) connects, and second end of resistance R24 is connected with the base stage of NPN triode Q1；
The colelctor electrode of NPN triode Q1 is connected with the first end of the base stage and resistance R23 of NPN triode Q2 respectively, and the second of resistance R23
End is connected with the colelctor electrode of NPN triode Q3, the grounded emitter of NPN triode Q1；The emitter stage of NPN triode Q2 connects
Ground, the colelctor electrode Jing resistance R27 of NPN triode Q2 are connected with the negative electrode of diode D7；The anode of diode D7 respectively with optocoupler
The first end connection of the negative electrode of light emitting diode and resistance R29 in U6；Second end of resistance R29 respectively with optocoupler U6 in light two
The first end connection of the anode and resistance R28 of pole pipe；Second end of resistance R28 is connected with the emitter stage of NPN triode Q3；It is described
In optocoupler U6, the colelctor electrode of triode is connected with the feedback input end of the second flyback PFC main control unit 1047；The optocoupler
The grounded emitter of triode in U6.
The overvoltage protection feedback control unit 1046 in the present embodiment, in the second flyback pfc circuit module 104
Including resistance R30, resistance R31, resistance R32, resistance R33, electric capacity C8, electric capacity C15, electric capacity C16, Zener diode ZD3, two poles
Pipe D8 and second voltage comparator U5.Specifically, the first end of the resistance R30 is being with the first backlight LED light string 301 just
Pole connects (namely the first end of the resistance R30 is connected with the output end of the second output rectification filter unit 1048), institute
State resistance R31 ground connection described in the second end Jing of resistance R30；The two ends of the resistance R31 are also parallel with electric capacity C16；The resistance
The first end of R32 is connected with the first voltage comparator U4 power positive ends, and the second end Jing electric capacity C15 of the resistance R32 connect
Ground；The negative electrode of Zener diode ZD3 in-phase input end respectively with the second voltage comparator U5, the resistance R20
The second end and the resistance R32 the second end connection, the plus earth of the Zener diode ZD3；The first voltage ratio
Inverting input compared with device U4 is connected with second end of the resistance R30, the power positive end of the second voltage comparator U5 with
Power positive end connection (not shown annexation) of the first voltage comparator U4, the power supply of the second voltage comparator U5
Negativing ending grounding；The output end of the second voltage comparator U5 is connected with the negative electrode of the diode D8, the diode D8's
Anode is connected with the negative electrode of the light emitting diode in the optocoupler U6；The first end of the electric capacity C8 is compared with the second voltage
The output end connection of device U5, the anti-phase input of the second end Jing resistance R33 and second voltage comparator U5 of the electric capacity C8
End connection.
In the present embodiment, the second flyback PFC main control unit 1047 in the second flyback pfc circuit module 104 includes
Flyback PFC chip U7, electric capacity C9, electric capacity C10, electric capacity C17, resistance R35, resistance R36, PMOS QS2 and sustained diode 5.
Specifically, exchange detection input pin AC (namely the of the second flyback pfc circuit module 104 of the flyback PFC chip U7
One detection input) it is connected with second end of the resistance R15, the input voltage waveform detection pin of the flyback PFC chip U7
VFF (namely second detection input of the second flyback pfc circuit module 104) is connected with second end of the resistance R15,
The grounding leg GND ground connection of the flyback PFC chip U7, the current detecting pin CS of the flyback PFC chip U7 respectively with the electricity
Hold the first end connection of the first end and the resistance R35 of C9, the high voltage startup pin HV of the flyback PFC chip U7 is whole with described
The output end connection of stream filter circuit module 102, the operating voltage input pin VCC of the flyback PFC chip U7 and two pole
The negative electrode connection of pipe D6, electric capacity C17 ground connection, the flyback PFC core described in the feed back input pin FB Jing of the flyback PFC chip U7
The feed back input pin FB of piece U7 also dims the triode in the optocoupler U6 in feedback control unit 1045 with backlight LED
Colelctor electrode connection (the feed back input pin FB of the flyback PFC chip U7 namely the second flyback PFC main control unit 1047
Feedback input end), the driving output pin DRV of the flyback PFC chip U7 is connected with the grid of PMOS QS2；The electricity
Hold the second end ground connection of C9；The first end of the electric capacity C10 is connected with the operating voltage input pin VCC of the flyback PFC chip U7
Connect, the second end ground connection of the electric capacity C10；The first end of the resistance R36 respectively with the drain electrode of PMOS QS2 and described
The second end connection of resistance R35, the second end ground connection of the resistance R36；The source electrode of PMOS QS2 respectively with the afterflow
The second end connection of the anode of diode D5 and the inductance LP2, the source electrode of PMOS QS2 namely second flyback
The control output end of PFC main control units 1047；The primary line of the negative electrode of the sustained diode 5 and the flyback transformer TX2
The Same Name of Ends connection of circle S4.
The second output rectification filter unit 1048 in the second flyback pfc circuit module 104 includes diode
D3, diode D4, electric capacity C11 and electric capacity C12.Specifically, the anode of the diode D3 is secondary with the flyback transformer TX2
The Same Name of Ends connection of level coil S5, the negative electrode of the diode D3 is the output of the second output rectification filter unit 1048
End, the negative electrode of the diode D3 are connected with the positive pole of the first backlight LED light string 301；The negative electrode of the diode D4 with
The Same Name of Ends connection of the secondary coil S6 of the flyback transformer TX2, the anode of the diode D4 and second backlight LED
The negative pole connection of lamp string 302；The first end of the electric capacity C11 is connected with the negative electrode of the diode D3, and the of the electric capacity C11
Two ends are grounded；The first end ground connection of the electric capacity C12, second end of the electric capacity C12 and the second backlight LED light string 302
Negative pole connection.
In the lump in reference Fig. 1, Fig. 3 and Fig. 5 the present embodiment, described second in the second flyback pfc circuit module 104
Input voltage measurement unit 1042 (i.e. described resistance R13, resistance R14, resistance R15 and resistance R16) is to rectifying and wave-filtering electricity
Exchange steamed bun ripple signal (the also referred to as input electricity of the second flyback pfc circuit module 104 of the 100HZ of the output of road module 102
Pressure) magnitude of voltage and voltage waveform detected respectively；Flyback PFC chip in the second flyback PFC main control unit 1047
Voltages of the U7 according to detected by the second input voltage measurement unit 1042 and its feed back input pin FB institutes feed back input
Light modulation feedback control signal, control the flyback transformer TX2 and export corresponding voltage to the backlight LED light string；This reality
Apply in example, when the current voltage of the positive pole of backlight LED light string is too high, the overvoltage protection feedback control unit will export corresponding
Overvoltage protection feedback control signal to the flyback PFC chip U7 feed back input pin FB, therefore, the flyback PFC chip
U7 is fed back defeated always according to the voltage and its feed back input pin FB detected by the second input voltage measurement unit 1042
The overvoltage protection feedback control signal for entering, controls the flyback transformer TX2 and exports corresponding voltage to backlight LED light string, right
The backlight LED light string carries out overvoltage protection.In the present embodiment, diode D3 and electric capacity C11 is to the flyback transformer TX2's
The voltage of secondary windings S5 outputs carries out rectifying and wave-filtering, obtains the cathode voltage of backlight LED light string；Diode D4 and electric capacity C12
Rectifying and wave-filtering is carried out to the voltage that the secondary windings S6 of the flyback transformer TX2 is exported, the negative electricity of backlight LED light string is obtained
Pressure；The electric current of backlight LED light string flows through the light emitting diode in optocoupler U3, then is controlled by the transfer ratio to optocoupler U3, and
The electric current of backlight LED light string is turned by a certain percentage by the collector terminal of the triode in optocoupler U3 by being connected with resistance R17
Resistance R17 is changed to, is then amplified by the partial pressure inspection of resistance R19 and resistance R20 and the error of first voltage comparator U4,
Jing optocouplers U6 feeds back to the feed back input pin FB of the flyback PFC chip U7 again, and the flyback PFC chip U7 passes through internal high pressure
The startup of start-up circuit, the flyback PFC chip U7 is by the voltage detected by the second input voltage measurement unit 1042
The feedback signal being input into the feed back input pin FB of the flyback PFC chip U7 carries out the computing of complexity, the flyback PFC core
Piece U7's drives output pin DRV by exporting the grid of the drive control signal to PMOS QS2 of different duty, to control
That makes PMOS QS2 is turned on and off the time, makes the electric current of PMOS QS2 with the exchange steamed bun ripple signal of input
Change and change (as using critical current pattern), while realizing that PFC is corrected, play the electric current of control backlight LED light string
Purpose.In the present embodiment, NPN triode Q3, resistance R25, Zener diode ZD2 and electric capacity C13 constitute series voltage stabilizing electricity
Road, the serial regulating circuit are that first voltage comparator U4 and second voltage comparator U5 provide supply voltage；In the present embodiment,
Resistance R32, Zener diode ZD315 and electric capacity C15 constitute simple RD strings equalizing network, as reference voltage, in the present embodiment,
The current control and overvoltage protection of backlight LED light string, using this voltage as reference voltage；In the present embodiment, as resistance R19 and
When the midpoint partial pressure of resistance R20 is less than benchmark, conductings of the first voltage comparator U4 by control diode D7, to reach
To the purpose of the electric current of control backlight LED light string；In the present embodiment, the resistance R26 and electric capacity C7 constitutes RC feedback compensation nets
Network, controls the gain of the first voltage comparator U4；The simulation is input into by the simulation dimming control signal input 1043
Dimming control signal is added to by taking that resistance R19 and resistance R20 are constituted by resistance R21 using the DC control signal of 0-3V
In sample circuit, to realize simulating the function of light modulation；The digital dimming is input into by the digital dimming control signal input 1044
Pulse control signal of the control signal using 0-3V, the frequency range of pulse control signal is 100Hz to 1000Hz, the numeral
The digital dimming control signal is input into by dimming control signal input 1044 passes through NPN triode Q1 and NPN triode Q2
Two-stage is swung to, and by the break-make of resistance R27 controlled output electric currents, realizes pulse modulated purpose, also, the present embodiment can also be real
Now simulation light modulation and the mixing dimming function of digital dimming.
The resistance R31, resistance R31 and electric capacity in the present embodiment, in the overvoltage protection feedback control unit 1046
C16 constitutes voltage sampling resistor, is sampled with the cathode voltage to the first backlight LED light string 301.Due to resistance R30
The positive pole of backlight LED light string is connected to, the partial pressure of the cathode voltage of backlight LED light string is examined by resistance R30 and resistance R31
Survey, when the cathode voltage of backlight LED light string reaches certain value, second voltage comparator U5 reversions, by optocoupler U6, reach control
The purpose of the cathode voltage upper limit of backlight LED light string processed, so as to realize the function of overvoltage protection.
The second flyback pfc circuit module 104 in the present embodiment is to containing 2 string backlight LED light strings (i.e. described the
One backlight LED light string 301 and the second backlight LED light string television set 302) provides backlight electric power, second flyback PFC
The flyback transformer TX2 in circuit module 104 is with two independent and phase place identical secondary windings (i.e. secondary windings
S5 and secondary windings S6), by the first backlight LED light string 301 and the second backlight LED light string 302 as shown in Figure 5
Connected mode, the first backlight LED light string 301 and the second backlight LED light string 302 are formed in into same electric current loop
Lu Zhong, only detects electric current wherein all the way, and is adjusted, so that it may synchronous to realize to 301 He of the first backlight LED light string
The purpose of the current control of the second backlight LED light string 302.
Also, in the present embodiment, when the output loose contact of the second flyback pfc circuit module 104, described first
The cathode voltage of backlight LED light string 301 is possible to too high situation occur, and the overvoltage protection feedback control unit 1046 is adopted
Independent sample circuit, when the cathode voltage for detecting the first backlight LED light string 301 is too high, immediately by described
The second voltage comparator U5 in two flyback pfc circuit modules 104 is by the output voltage drop of the flyback transformer TX2
It is low, or even the work of stopping backlight LED light string, reach the purpose of protection backlight LED light string.
The power circuit of embodiment of the present invention television set, relative to the power circuit of television set in prior art, reduces
Conventional independent PFC correcting circuits module, and the power supply of the movement of television set directly supplied by the first flyback pfc circuit module
Electricity, the power supply of two channel LED lamp string of backlight are directly powered by the second flyback pfc circuit module.40-55 of the present invention cun of TV
The power circuit of machine reduces the management and control area requirement to backlight LED light string conducting voltage；Meanwhile, embodiment of the present invention television set
Power circuit also has the advantages that few circuit function module, simple circuit, efficiency high and low cost.
The present invention also provides a kind of television set, and the television set includes the power circuit of television set, the power supply electricity of the television set
The structure on road can refer to above-described embodiment, including the connected mode of the multi-channel LED lamp string of other schemes, will not be described here.
Naturally, as the television set of the present embodiment employs the technical scheme of the power circuit of above-mentioned television set, therefore the electricity
There is all of beneficial effect of the power circuit of above-mentioned television set depending on machine.
The preferred embodiments of the present invention are these are only, the scope of the claims of the present invention is not thereby limited, it is every using this
Equivalent structure or equivalent flow conversion that bright specification and accompanying drawing content are made, or directly or indirectly it is used in other related skills
Art field, is included within the scope of the present invention.
Claims (9)
1. a kind of power circuit of television set, it is characterised in that the power circuit of the television set include ac power input end,
Current rectifying and wave filtering circuit module, the first flyback pfc circuit module and the second flyback pfc circuit module；Wherein：
The ac power input end, for input ac power；
The current rectifying and wave filtering circuit module, for carrying out rectification filter to the AC power that the ac power input end is input into
Ripple, output one exchange steamed bun ripple power supply signal to the first flyback pfc circuit module；
The first flyback pfc circuit module, for carrying out the control of flyback PFC to the exchange steamed bun ripple power supply signal, is electricity
Movement depending on machine is powered；
The second flyback pfc circuit module, for the exchange steamed bun ripple electricity exported to the current rectifying and wave filtering circuit module
Source signal carries out the control of flyback PFC, and the backlight LED light string for television set provides corresponding supply voltage, to control the backlight
The brightness of LED string.
2. the power circuit of television set as claimed in claim 1, it is characterised in that the input of the current rectifying and wave filtering circuit module
End is connected with the ac input end, the output end of the current rectifying and wave filtering circuit module respectively with the first flyback pfc circuit
The input connection of the input of module and the second flyback pfc circuit module；The first flyback pfc circuit module it is defeated
Go out end to be connected with the power end of the movement of television set；The output end of the second flyback pfc circuit module and the backlight of television set
LED series winding connects.
3. the power circuit of television set as claimed in claim 1 or 2, it is characterised in that the first flyback pfc circuit module
Including the first transformer unit, the first input voltage measurement unit, output voltage feedback detector unit and the first flyback PFC master control
Unit；Wherein：
First transformer unit, for carrying out voltage transformation to the voltage of the output end of the current rectifying and wave filtering circuit module；
The first input voltage measurement unit, for examining to the voltage of the output end of the current rectifying and wave filtering circuit module
Survey；
The output voltage feeds back detector unit, for carrying out to the voltage of the output end of the first flyback pfc circuit module
Feedback detection；
The first flyback PFC main control unit, for the voltage according to detected by the first input voltage measurement unit and
The output voltage feeds back the fed back voltage for detecting of detector unit, controls the corresponding electricity of the first transformer unit output
It is depressed into the movement of television set.
4. the power circuit of television set as claimed in claim 3, it is characterised in that the first flyback pfc circuit module is also
Including the first output rectification filter unit；The first output rectification filter unit, for defeated to first transformer unit
The voltage for going out carries out rectifying and wave-filtering, and by the movement of the voltage output after rectifying and wave-filtering to television set, is that the movement of television set is supplied
Electricity.
5. the power circuit of television set as claimed in claim 4, it is characterised in that the first input voltage measurement unit
Input is connected with the output end of the current rectifying and wave filtering circuit module, the output end of the first input voltage measurement unit and institute
State the detection input connection of the first flyback PFC main control unit；The input of output voltage feedback detector unit with it is described
The output end connection of the first flyback pfc circuit module, the output end of the output voltage feedback detector unit are anti-with described first
The feedback input end connection of sharp PFC main control units；The control output end of the first flyback PFC main control unit becomes with described first
The primary coil connection of depressor unit；First output rectification filter unit described in the secondary coil Jing of first transformer unit
It is connected with the movement of television set.
6. the power circuit of television set as claimed in claim 1, it is characterised in that the second flyback pfc circuit module bag
Include the second transformer unit, the second input voltage measurement unit, simulation dimming control signal input, digital dimming control signal
Input, backlight LED light modulation feedback control unit, overvoltage protection feedback control unit and the second flyback PFC main control unit；Its
In：
Second transformer unit, for carrying out voltage transformation to the voltage of the output end of the current rectifying and wave filtering circuit module；
The second input voltage measurement unit, for examining to the voltage of the output end of the current rectifying and wave filtering circuit module
Survey；
The simulation dimming control signal input, for being input into simulation dimming control signal；
The digital dimming control signal input, for being input into digital dimming control signal
Backlight LED dims feedback control unit, for carrying out feedback detection to the electric current of the backlight LED light string of television set,
And the backlight LED light detected according to the simulation dimming control signal or the digital dimming control signal and feedback
The electric current of string, the corresponding light modulation feedback control signal of output is to the second flyback PFC main control unit；
The overvoltage protection feedback control unit, for detecting to the current voltage of the backlight LED light string positive pole of television set,
And when the current voltage of the backlight LED light string positive pole is too high, corresponding overvoltage protection feedback control signal is exported to described
Second flyback PFC main control unit；
The second flyback PFC main control unit, for the input electricity according to detected by the second input voltage measurement unit
Pressure and the light modulation feedback control signal, control second transformer unit and export corresponding voltage to the backlight LED light
String, the brightness to the backlight LED light string are adjusted；And according to detected by the second input voltage measurement unit
Input voltage and the overvoltage protection feedback control signal, control second transformer unit and export corresponding voltage to described
Backlight LED light string, carries out overvoltage protection to the backlight LED light string.
7. the power circuit of television set as claimed in claim 6, it is characterised in that the second flyback pfc circuit module is also
Including the second output rectification filter unit；The second output rectification filter unit, for defeated to second transformer unit
The voltage for going out carries out rectifying and wave-filtering, and by the backlight LED light string of the voltage output after rectifying and wave-filtering to television set, is the backlight
LED statements based on collusion electricity.
8. the power circuit of television set as claimed in claim 7, it is characterised in that the second input voltage measurement unit
Input is connected with the output end of the current rectifying and wave filtering circuit module, the inspection of output end and the second flyback PFC main control unit
Survey input connection；
The first input end and backlight LED light series winding of backlight LED light modulation feedback control unit connects, the second input with
The simulation dimming control signal input connection, the 3rd input is connected with the digital dimming control signal input, defeated
Go out end to be connected with the feedback input end of the second flyback PFC main control unit；
The input of the overvoltage protection feedback control unit is connected with the positive pole of the backlight LED light string, output end with it is described
The feedback input end connection of the second flyback PFC main control unit；
The control output end of the second flyback PFC main control unit is connected with the primary coil of second transformer unit；Institute
State the second output rectification filter unit described in the secondary coil Jing of the second transformer unit to connect with backlight LED light series winding.
9. a kind of television set, it is characterised in that the television set includes the television set any one of claim 1 to 8
Power circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611128654.8A CN106549588A (en) | 2016-12-09 | 2016-12-09 | The power circuit and television set of television set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611128654.8A CN106549588A (en) | 2016-12-09 | 2016-12-09 | The power circuit and television set of television set |
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| Publication Number | Publication Date |
|---|---|
| CN106549588A true CN106549588A (en) | 2017-03-29 |
Family
ID=58397300
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611128654.8A Pending CN106549588A (en) | 2016-12-09 | 2016-12-09 | The power circuit and television set of television set |
Country Status (1)
| Country | Link |
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| CN (1) | CN106549588A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108809064A (en) * | 2018-06-07 | 2018-11-13 | 青岛浩海网络科技股份有限公司 | A kind of power supply for forest fire protection all-in-one machine |
| CN110166721A (en) * | 2019-06-17 | 2019-08-23 | 深圳创维－Rgb电子有限公司 | The straight crystal drive circuit of interleaved PFC constant current, driving power and television set |
| WO2022041873A1 (en) * | 2020-08-24 | 2022-03-03 | 海信视像科技股份有限公司 | Display apparatus and step power circuit |
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| CN102523406A (en) * | 2011-12-07 | 2012-06-27 | 青岛海信电器股份有限公司 | Power circuit structure and LED liquid crystal television |
| CN104935843A (en) * | 2015-06-16 | 2015-09-23 | 康佳集团股份有限公司 | LED (Light-Emitting Diode) television two-in-one power supply circuit and LED television |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102523406A (en) * | 2011-12-07 | 2012-06-27 | 青岛海信电器股份有限公司 | Power circuit structure and LED liquid crystal television |
| CN104935843A (en) * | 2015-06-16 | 2015-09-23 | 康佳集团股份有限公司 | LED (Light-Emitting Diode) television two-in-one power supply circuit and LED television |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108809064A (en) * | 2018-06-07 | 2018-11-13 | 青岛浩海网络科技股份有限公司 | A kind of power supply for forest fire protection all-in-one machine |
| CN110166721A (en) * | 2019-06-17 | 2019-08-23 | 深圳创维－Rgb电子有限公司 | The straight crystal drive circuit of interleaved PFC constant current, driving power and television set |
| CN110166721B (en) * | 2019-06-17 | 2021-08-31 | 深圳创维－Rgb电子有限公司 | Staggered PFC (Power factor correction) constant-current direct drive circuit, driving power supply and television |
| WO2022041873A1 (en) * | 2020-08-24 | 2022-03-03 | 海信视像科技股份有限公司 | Display apparatus and step power circuit |
| US11825577B2 (en) | 2020-08-24 | 2023-11-21 | Hisense Visual Technology Co., Ltd. | Display apparatus and step power circuit |
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Application publication date: 20170329 |