CN1540978A - Device for turning off overdriven color TV set - Google Patents

Device for turning off overdriven color TV set Download PDF

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Publication number
CN1540978A
CN1540978A CNA2003101108602A CN200310110860A CN1540978A CN 1540978 A CN1540978 A CN 1540978A CN A2003101108602 A CNA2003101108602 A CN A2003101108602A CN 200310110860 A CN200310110860 A CN 200310110860A CN 1540978 A CN1540978 A CN 1540978A
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Prior art keywords
circuit
overload
branch road
power supply
transformer
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Granted
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CNA2003101108602A
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CN100418368C (en
Inventor
俊 戴
戴俊
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Shenzhen Skyworth RGB Electronics Co Ltd
Shenzhen Chuangwei RGB Electronics Co Ltd
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Shenzhen Skyworth RGB Electronics Co Ltd
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Publication of CN1540978A publication Critical patent/CN1540978A/en
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Publication of CN100418368C publication Critical patent/CN100418368C/en
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Abstract

Scheme of power supply distribution of energy saving and multiple functional control technique is adopted in the invention. Flyback transformer through rectification loop in positive direction and negative direction forms different functional over loading sampling detection sources. Secondary side of switching mode power supply transformer through reversed polarity loop and like polarity rectification loop forms different functional over loading sampling detection sources. The said detection sources through different branches of pressure-sensitive switch parts are connected to a turning power off autolocking executive circuit in over loading. Thus, in various over loading condition, parts are protected in time of over loading occurs, fault will not be chained and extended.

Description

Colour TV overload shutdown unit
Affiliated technical field
The present invention relates generally to TV technology.
Background technology
Prior art colour TV overload protecting circuit; defencive function is more single; if need multinomial defencive function; must form by a plurality of single protective circuits; prior art protective circuit more complicated; often need to use the self-defined relevant overload function leading foot of inner X ray function of integrated package or micro controller CPU OPT supporting, also easy mistake control or out of control, and every protective circuit cost height.Wherein, in the overcurrent protection of prior art horizontal output stage; it all is to be series at the loop hot end that overcurrent sample detects resistance; this overcurrent sample detect resistance to common port () potential difference is very big; general above more than the 110V; strengthen the positive-negative-positive overcurrent sample amplifier tube proof voltage requirement that should need, cost is higher.Because the shortcoming of prior art overload protection P/C ratio is difficult to a large amount of the operation and uses.Colour TV is not if add protective circuit, in case break down, the chain generation of meeting is major break down more, particularly burns the colour TV phenomenon.At prior art P/C ratio characteristics, for this reason:
Summary of the invention
The object of the invention: the dual-purpose performance that should use up of performance circuit, reduce the number of the element number, it is minimum to make every effort to cost, and defencive function is the most complete, and is the most reliable, makes properties of product/price than improving.
Realize that indispensable scheme of the present invention is: [Fig. 1, Fig. 3 example]: contain switching mode power supply transformer (T), kickback transformer (FBT) and interlock circuit thereof, the color television set of being formed, adopt multinomial difference in functionality overload sampling detection resources, after passing through different pressure sensitive switch devices (as: voltage-stabiliser tube) respectively, connecting overload shutdown (standby) self-locking executive circuit jointly.This overload shutdown (standby) self-locking executive circuit is connected with micro controller cpu power control end DCON/OFF branch road Pr again.Reach any load overload shutdown purpose.Concrete indispensable scheme feature is: kickback transformer (FBT) is secondary through each self-forming difference in functionality overload sampling detection resources of trace commutating circuit and flyback commutating circuit, together with T level of switching mode power supply transformer through reversed polarity loop and each self-forming difference in functionality overload of same polarity commutating circuit detection resources of taking a sample; After passing through different pressure sensitive switch device branch roads respectively, connecting overload shutdown (standby) self-locking executive circuit jointly.This overload shutdown executive circuit output J4 or J5 are connected with micro controller cpu power control end (DC ON/OFF) branch road Pr.Form special-shaped multiple tube and interlock circuit thereof by preposition amplifier tube A4 and switching tube VK, constitute overload shutdown latching circuit main body; Be connected in the current-limiting resistance R7 branch road of amplifier tube A4 base stage and switching tube VK collector electrode, have the positive feedback auto-lock function concurrently, make this amplifier tube A4 and switching tube VK form special-shaped multiple tube and have (can replace) thyristor SCR or integrated circuit X-ray protection function or the relevant overload of the self-defined end OPT of micro controller CPU prosecution function concurrently.Two triode A4 and VK base bias branch road J8, J7, J3 branch road are connected to difference in functionality overload sampling detection resources.Reach and to realize any load overload shutdown purpose.
Remarkable advantage of the present invention: defencive function is many, and overload protection is reliable and stable, and cost is minimum, stops that a certain component wear might cause the chain phenomenon of damaging again of other elements in the prior art.
In this specification, " trace rectification " refers to that pulse transformer is secondary by serial connection diode rectification loop and same polarity rectification filtering circuit that originally the coil on/off is identical." flyback rectification " refers to that pulse transformer is secondary by serial connection diode rectification loop and reversed polarity rectification filtering circuit that originally the coil on/off is opposite." overload shutdown " notion extension no doubt comprises that overload exchanges complete closedown ACOFF or overload standby DCOFF function.
Description of drawings
Accompanying drawing is totally 10 width of cloth, only innovates the indispensable essential characteristics of part in detail.φ represents variable or removable end.During the former elementary conducting of pulse transformer, primary and secondary induction polarity end of the same name is represented with black round spot without exception.Common triode can preferably replace into field effect transistor etc.Specification and accompanying drawing are not explained, and explain by the current example of passing through.The indispensable scheme parent map of Fig. 1 example the innovation, Fig. 3 is Fig. 1 functional-block diagram, SCR overcurrent protection of Fig. 2 example thyristor and deflecting coil disconnect protection figure.Therefore the double Fig. 2 example thyristor SCR function that contains of Fig. 1, can save (that is: need not to increase again) thyristor or integrated fast inside provides relevant overload protecting circuit.[exemplary plot 2 purposes be to promote understanding Fig. 1 have concurrently save thyristor SCR function].Remote control of Fig. 4 example or electrical network overvoltage pulse formula exchange total shutdown; Fig. 5 or Fig. 6 example network voltage detection scheme can realize electrical network overvoltage or under-voltage shutdown function with after circuit among Fig. 1 or Fig. 4 is connected.And after can in micro controller CPU, handling, realize overload shutdown function, and can shield apparent line voltage value height.Fig. 7, Fig. 8, Fig. 9 example the innovation be specifically utilization on TV.Figure 10 example is fit to the OCL load overcurrent protection of negative and positive dual power power supply.In the different accompanying drawings, contain same tag, refer to that function or performance effect are identical.Vcc can refer to arbitrary power supply hot end, can be the different electrical power voltage value, and except that Vcc, same reference numerals person can be connected in the same accompanying drawing.Each figure effect sees hereinafter explanation for details.
Embodiment
Describe realization the innovation best way in detail below in conjunction with the accompanying drawing example.Preamble has been stated or has no longer been repeated in conjunction with continue to use prior art or in like manner should change etc.
Fig. 4 example: [can adopt or need not to contain the interchange master switch K of relay].Form special-shaped multiple tube and interlock circuit thereof by preposition amplifier tube A44 and switching tube VK,, be connected in amplifier tube A44 base stage and switching tube VK collector electrode, have pulsed and switch advantage fast by constituting positive feedback branch by resistance R 68 and capacitor C 68.Cut down switching tube VK conducting/turn off process by way of the amplification region time, have voltage comparator or this schmitt trigger performance, can directly be connected, just can realize that remote control or electrical network overvoltage pulse formula exchange the complete closedown function with the high low circuit of detection of grid voltage of taking a sample indirectly; (otherwise can not independently realize electrical network overvoltage always shut down ACOFF function).T level of dual-purpose switching mode power supply transformer (cold base plate) winding detection of grid voltage fluctuation scheme can be with reference to Fig. 4, Fig. 5, Fig. 6 example.At switching mode power supply transformer T or power frequency AC transformer secondary output, by behind serial connection and the diode V61 same polarity commutation capacitor C61 filter circuit that originally the coil on/off is identical, originally voltage (pressure swing type Switching Power Supply=input terminal voltage, it is poor that tandem tap power supply=input terminal voltage deducts main output end voltage) relation in direct ratio magnetizes at the coil two ends when these detection capacitor C 61 output voltages and switching tube conducting.Therefore, can be used as the detection resources of detection of grid voltage height.Via voltage-stabiliser tube D9 or Schmidt trigger (voltage comparator), after handling the pressure sensitive switch device branch road that waits the conducting of formation normality shutoff overload in the integrated package (CPU), connect finally that to control with the relay K be the overload shutdown circuit of core, can realize that overload exchanges total shutdown ACOFF function or DCOFF function.In like manner, FBT level of kickback transformer is through trace commutating circuit and each self-forming overload detection source of flyback commutating circuit,,, behind the pressure sensitive switch device, connect and controlling the overload shutdown circuit through reversed polarity commutating circuit and each self-forming detection resources of same polarity commutating circuit together with T level of switch transformer.The shutdown order after can handling by micro controller CPU, is sent in the overload detection source during overload, can realize ACOFF or DCOFF function.The detection resources C61 of reflection power network fluctuation can fall through series connection behind (branch) piezoresistance R118/R119 and the self-defined end OPT of micro controller CPU interface.Can shield and show line voltage numerical value.Can connect triode A4 base stage branch road J8 or switching tube VK base stage branch road J7 by diode D9B branch road, realize electrical network under-voltage protection or plug loose contact protection; Can connect switching tube VK base stage branch road J7 or triode A4 base stage branch road J8 by diode D9 branch road, realize the electrical network overvoltage protection.On stackable other positive source of secondary detection capacitor C 61 cold ends of tandem tap power supply induction reactance choking coil (that is: switch transformer T).The pressure swing type Switching Power Supply then need not.So serial connection is proofreaied and correct the apparent line voltage numerical value occasion of the applicable pressure swing type Switching Power Supply of voltage-stabiliser tube D61 colour TV screen in the accompanying drawing, but adapted tandem tap power supply short circuit is removed voltage-stabiliser tube D61.
Colour TV kickback transformer secondary circuit and relevant horizontal output stage thereof are that secondary energy sources produce circuit behind switching power supply, are the tandem circuits of colour TV most critical, also are the highest positions of failure rate.So setting up FBT level overload protection is the tandem circuit that prevents that the fault chain reaction from more enlarging.As: some was the sparking of making moist of the cavity cap of glitch originally, the fragile picture tube of the untimely repairing of user, electric arc might burn cavity cap etc. during high voltage arc, even causes that complete machine is on fire, damages manufacturer's image.The present invention's very succinctly multi-functional reliably (more than seven kinds) overload protecting circuit is only used one or two triode and a small amount of peripheral cell thereof, is constructed as follows:
When the skew of Switching Power Supply voltage stabilizing value raises, can cause that rectification of kickback transformer active line and line retrace commutating voltage all raise, and all have harm to each circuit load.For this reason, optional wherein as detection resources, turn-off the pressure sensitive switch device W91 and the W95 branch road of overload conducting respectively by normality, chain overload shutdown latching circuit.
When colour TV line retrace main capacitance lost efficacy, can cause that voltage raises behind the kickback transformer FBT line retrace rectifying and wave-filtering, (especially to high potential assembly, power supply gives the picture tube very harmful).For this reason; can select dual-purpose filament line retrace commutating pulse as detection resources; FBT level of kickback transformer Filament Winding; after filament current-limiting resistance R96 current limliting; power supply is to picture tube CRT filament and after 64 filtering of diode U23 reversed polarity rectification (that is: flyback rectification) capacitor C are direct current simultaneously; constitute the detection resources of reflection flyback commutating pulse voltage height; through being connected in series normality behind the pressure sensitive switch device W95 of overload conducting; be connected in preposition pipe A4 collector branch road and rearmounted pipe VK base stage branch road interface point J7, as reversed polarity rectification (line flyback pulse) overvoltage protection.The innovation overcomes when selecting different FBT for use in the past, detects without sampling behind the serial connection filament current-limiting resistance and brings mistake control or shortcoming out of control.
When the colour TV high voltage arc or look and put source inefficacy or CRT and periphery thereof and look when putting plate and going wrong, can cause that FBT level superhigh pressure winding commutating circuit electric current is very big, can make FBT level reversed polarity rectification superhigh pressure winding SHV cold end ABL current potential lower (be because of the pressure drop of major loop current-limiting resistance R ABL overcurrent cause greatly), behind current-limiting resistance R95 capacitor C 92 integrations, be direct current, when exporting pure direct current prosecution component and reaching certain amplitude, can puncture normality turn-offs, behind the pressure sensitive switch device W92 branch road of overvoltage conducting, be connected in the preposition pipe A4 of overload shutdown latching circuit base stage branch road, the excessive or high voltage arc protection of making moist as beam electronic current; Chain overload shutdown circuit action.[" X " refers to X-ray protection in the accompanying drawing, or connects the self-defined leading foot of the relevant OTP of CPU or directly connect the ACOFF circuit or direct DCOFF circuit].
Because active line rectification maximum conduction angle is 52us, turn-off 12us, so internal resistance is little and highly stable reliable.So the level active line rectifying and wave-filtering source that comes from FBT time is often got by colour TV micro-signal system.But when over current fault takes place, because of the primary electrical sensibility reciprocal is cut down in the same polarity rectification, so chain very harmful.So set up the active line overcurrent protection.For this reason, get FBT arbitrary power supply J2VCC high potential of level of source switch power transformer T or kickback transformer, (particularly as getting the secondary main trace rectification master load power source of source kickback transformer, as: field ionization source or 12V power supply), J9 behind about 1 Ω of sample resistance R91, other pressurizers or other loads are given in power supply again.This overcurrent sample resistance R 91 produces voltage drop, is connected in amplifier tube A4 base stage by biasing resistor R92, as low pressure small-signal load overcurrent protection.When the sample resistance pressure drop reaches 0.5V when above, behind capacitance-resistance R92 and C91 integration, make the amplifier tube A4 of former shutoff amplify conducting, chain overload shutdown circuit action.After resistance R 47 was used to limit the overcurrent protection action, self-locking power supply 5V (CPU) flow backwards to overcurrent (short circuit) load J9 branch road behind diode D95.Under some occasion, (as: need not this over-current detection load J9 branch road), resistance R 47 can be removed short circuit or replace with diode.
During overload shutdown latching circuit power supply source J2 VCC overtension, turn-off the pressure sensitive switch device W91 of overload conducting through normality after, be connected in preposition amplifier tube A4 base stage branch road J8, as active line rectification overvoltage protection or switch power supply secondary reversed polarity rectification overvoltage protection;
In like manner; when colour TV field output stage or audio power amplifier go wrong; the OTL mid point often is offset; otl circuit makes output mid point electric capacity current potential seriously be offset unusually; end the pressure sensitive switch device W94 of overload conducting through normality after; be connected in the preposition pipe A4 of overload shutdown latching circuit base stage branch road J8, protect as the OTL circuit abnormality.Also can chain overload shutdown circuit action by voltage-stabiliser tube W94 branch road and diode D98 resistance R 100 branch roads.The innovation is double to prevent that loud speaker or other OTL load from burning special efficacy is arranged.
Among the figure ACL (ABL) circuit is improved to some extent.ACL adopts dual-time constant R96, C93 and R97, C98.Sample resistance RABL can the take a sample secondary line flyback pulse of source kickback transformer or other arbitrary power supply J1 or ground connection of monitoring beam current varies.As: the electric tuning power supply, filament supply or 12V to 5V power supply all can constitute the superhigh pressure winding loop.
The overcurrent protection sample circuit all was that the serial connection loop is adjacent to hot end in the past; this overcurrent sample detect resistance to common port " " potential difference have very big; as: colour TV horizontal output stage H.OUT; general above more than the 110V; increasing institute joins needs the requirement of positive-negative-positive overcurrent sample amplifier tube proof voltage, so cost is higher.The present invention's design viewpoint that breaks traditions, overcurrent sample detect the resistance R _ f vicinity be connected in the loop common port " ", as electronegative potential overcurrent sample detection resources.The arbitrary transformer secondary output in the source of getting needs the winding of overcurrent protection, in diode U commutation capacitor C filter circuit cold end be not directly connected in common port " ", but by behind the serial connection current sampling resistor Rf, just contiguous be connected in the loop common port " ", make this overcurrent sample detect resistance R _ f hot end (+) connect common port " ", cold end (-) is connected in switching tube VK emitter or thyristor SCR negative electrode K; Switching tube VK base stage J3 or thyristor SCR control utmost point G is connected in overcurrent sample resistance R _ f hot end+(that is: common port " ") by the resistance R 46 that has bias capability concurrently.The present invention gives prominence to advantage, and increasing has overcurrent protection function to spend cost hardly.In like manner, can increase a plurality of (roughly the same switching tube VK is correlated with) overcurrent protection.Single switching tube VK occasion can be removed and short circuit diode VD7, and the present invention directly (independence) is common to any product that needs overcurrent protection.Be used on the colour TV, be particularly suitable for overcurrent protections such as line output H.OUT or audio power amplifier, an output, CPU.
In the colour TV line-scan circuit, after line linearity inductance, line deflector coil branch road easily open circuit, not only easily burn line output valve, but also fire hazardous.For this reason, set up horizontal deflection branch road LY open circuit protection.School electric capacity hot end J6 draws by the horizontal output stage pillow; behind the pressure sensitive switch device VDM branch road by the shutoff of serial connection normality, overload conducting; be connected in switching tube VK base stage J3 or thyristor SCR control utmost point G, as protection of line deflector coil LY branch circuit break and pincushion correction circuitry abnormal protection
Fig. 7, Fig. 8, Fig. 9 example the innovation be specifically utilization on TV.After T level of switching mode power supply transformer is by diode D611 commutation capacitor C630 filtering, be DC power supply as photoelectrical coupler N input power supply; this photoelectrical coupler N light-emitting diode negative terminal; turn-off the pressure sensitive switch device W15V branch road of overvoltage conducting by normality; be connected in normal/Opportunity awaiting control for linear pipe Q604 base stage or switching tube VK base stage branch road J7, as switch transformer T secondary output end overvoltage protection.The bright spot circuit is cut in the colour TV shutdown or shutdown mute circuit output can be connected with J7 in the overload shutdown latching circuit, can realize that electrical network interrupts or plug loose contact protection.
This specification colour TV comprises or direct general CRT, DVD, plasma, liquid crystal etc. and all relevant videos thereof show product or other electron and electrician products.The Figure of description parameter is only done reference for example, uses former adjustable variable element.The innovation (particularly overcurrent protection) can directly be expanded outer other electron and electrician technical field of utilization TV.

Claims (9)

1, contain switching mode power supply transformer (T), kickback transformer (FBT) and interlock circuit thereof, the color television set of being formed is characterized in that:
Kickback transformer (FBT) is secondary through trace commutating circuit and each self-forming difference in functionality overload sampling detection resources of flyback commutating circuit, and is secondary through reversed polarity loop and each self-forming difference in functionality overload sampling detection resources of same polarity commutating circuit together with switching mode power supply transformer (T); After passing through different pressure sensitive switch device branch roads respectively, connecting overload shutdown (standby) self-locking executive circuit jointly; This overload shutdown executive circuit output J4 or J5 are connected with micro controller (CPU) power control terminal (DC ON/OFF) branch road Pr.
2, circuit according to claim 1 is characterized in that: form special-shaped multiple tube and interlock circuit thereof by preposition amplifier tube (A4) and switching tube (VK), constitute overload shutdown latching circuit main body; Be connected in current-limiting resistance (R7) branch road of amplifier tube (A4) base stage and switching tube (VK) collector electrode, have the positive feedback auto-lock function concurrently, make this amplifier tube (A4) and switching tube (VK) form special-shaped multiple tube and have (can replace) thyristor (SCR) or integrated circuit X-ray protection function or the relevant overload of the self-defined end of micro controller (CPU) (OPT) prosecution function concurrently; Two triode A4 and VK base bias branch road J8, J7, J3 branch road are connected to difference in functionality overload sampling detection resources.
3, circuit according to claim 1, it waits to levy: the secondary reversed polarity rectification of kickback transformer (FBT) superhigh pressure winding SHV cold end ABL is direct current behind current-limiting resistance (R95) electric capacity (C92) smothing filtering, pressure sensitive switch device (W92) branch road by the shutoff of serial connection normality, overload conducting, be connected in the overload shutdown preposition pipe of latching circuit (A4) base stage branch road, the excessive or high voltage arc protection of making moist as beam electronic current; Otl circuit makes output mid point electric capacity current potential seriously be offset unusually, behind the pressure sensitive switch device (W94) of, overload conducting, is connected in the overload shutdown preposition pipe of latching circuit (A4) base stage branch road J8 through normality, protects as the OTL circuit abnormality; The secondary Filament Winding of kickback transformer (FBT), after filament current-limiting resistance (R96) current limliting, power supply is to picture tube (CRT) filament and after diode (U23) reversed polarity rectification (that is: flyback rectification) electric capacity (C64) filtering is direct current simultaneously, constitute the detection resources of reflection flyback commutating pulse voltage height, through being connected in series normality behind the pressure sensitive switch device (W95) of overload conducting, be connected in preposition pipe (A4) collector branch road and rearmounted pipe (VK) base stage branch road interface point J7, as reversed polarity rectification (line flyback pulse) overvoltage protection; During overload shutdown latching circuit power supply source (J2 VCC) overtension; turn-off the pressure sensitive switch device (W91) of overload conducting through normality after; be connected in preposition amplifier tube (A4) base stage branch road J8; as active line rectification overvoltage protection or switch power supply secondary reversed polarity rectification overvoltage protection: after getting source switch power transformer (T) or the secondary arbitrary power supply of kickback transformer (FBT) (J2VCC) hot end serial connection current sampling resistor (R91); could power and give load; this overcurrent sample resistance (R91) produces voltage drop; be connected in amplifier tube (A4) base stage by biasing resistor (R92), as low pressure small-signal load overcurrent protection.
4, circuit according to claim 1 is characterized in that: overcurrent sample detect resistance (Rf) contiguous be connected in the loop common port " ", as electronegative potential overcurrent sample detection resources.
5, according to claim 1 or the described circuit of claim 4, it is characterized in that: the arbitrary transformer secondary output winding in the source of getting, in diode (U) commutation capacitor (C) filter circuit cold end be not directly connected in common port " ", but by behind the serial connection current sampling resistor Rf, just contiguous be connected in the loop common port " ", make this overcurrent sample detect resistance (Rf) hot end (+) connect common port " ", cold end (-) is connected in switching tube (VK) emitter or thyristor (SCR) negative electrode K; Switching tube (VK) base stage J3 or thyristor (SCR) the control utmost point (G) by the resistance (R46) that has bias capability concurrently be connected in overcurrent sample resistance (Rf) hot end+and common port " " junction.
6, circuit according to claim 1; it is characterized in that: horizontal output stage pillow school electric capacity hot end J6; behind pressure sensitive switch device (VDM) branch road by the shutoff of serial connection normality, overload conducting; be connected in switching tube (VK) base stage J3 or thyristor (SCR) control utmost point G, as protection of line deflector coil (LY) branch circuit break and pincushion correction circuitry abnormal protection.
7, circuit according to claim 1; it is characterized in that: at switching mode power supply transformer T or industrial frequency AC transformer secondary output winding; by after serial connection and the diode same polarity commutation capacitor filtering that originally the coil on/off is identical; as indirect sampling detection of grid voltage height detection resources; through the pressure sensitive switch device (D9) of normality shutoff, overvoltage or under-voltage conducting or (D9B); be connected in triode (A4) base stage branch road J8 or switching tube (VK) base stage branch road J7, respectively as AC network overvoltage or under-voltage protection.
8, circuit according to claim 1; it is characterized in that: be DC power supply as photoelectrical coupler N input power supply after by diode (D611) commutation capacitor (C630) filtering in that switching mode power supply transformer (T) is secondary; this photoelectrical coupler (N) light-emitting diode negative terminal; turn-off pressure sensitive switch device (W15V) branch road of overvoltage conducting by normality; be connected in normal/Opportunity awaiting control for linear pipe (Q604) base stage or switching tube (VK) base stage branch road J7, as switch transformer (T) secondary output end overvoltage protection.
9, circuit according to claim 1 is characterized in that: the bright spot circuit is cut in the colour TV shutdown or shutdown mute circuit output can be connected with J7 branch road in the overload shutdown latching circuit.
CNB2003101108602A 2003-11-01 2003-11-01 Device for turning off overdriven color TV set Expired - Fee Related CN100418368C (en)

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CN2008102158762A Division CN101453112B (en) 2003-11-01 2003-11-01 Overcurrent protection circuit comprising multiple groups of loop load

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009089665A1 (en) * 2008-01-15 2009-07-23 Shenzhen Skyworth-Rgb Electronic Co., Ltd Protection device for supply circuit with positive and negative double power
CN101577419A (en) * 2009-06-22 2009-11-11 安徽摆客动力技术有限公司 Selflocking direct current supply short circuit protection circuit
CN1996692B (en) * 2006-08-31 2010-04-14 深圳创维-Rgb电子有限公司 Protection method of the dual-power field and its circuit
CN101175144B (en) * 2006-11-01 2010-08-18 青岛海信电器股份有限公司 Kinescope neck-cutting protection circuit and method thereof
CN103647261A (en) * 2013-12-28 2014-03-19 盖洪儒 Portable module protector specially for X-ray machine
CN106454172A (en) * 2016-12-22 2017-02-22 深圳Tcl数字技术有限公司 Power supply circuit and TV set

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CN101909383B (en) * 2009-06-02 2013-04-17 海洋王照明科技股份有限公司 Over-voltage locking protection circuit and power drive circuit using same

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Publication number Priority date Publication date Assignee Title
JP3215150B2 (en) * 1992-03-26 2001-10-02 株式会社東芝 Power switch circuit
CN1123500A (en) * 1994-11-25 1996-05-29 戴俊 Power-supply for remote control of colour television set
CN1384664A (en) * 2001-03-13 2002-12-11 戴俊 Remote control and overload shut-off device for color TV set

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1996692B (en) * 2006-08-31 2010-04-14 深圳创维-Rgb电子有限公司 Protection method of the dual-power field and its circuit
CN101175144B (en) * 2006-11-01 2010-08-18 青岛海信电器股份有限公司 Kinescope neck-cutting protection circuit and method thereof
WO2009089665A1 (en) * 2008-01-15 2009-07-23 Shenzhen Skyworth-Rgb Electronic Co., Ltd Protection device for supply circuit with positive and negative double power
US8159799B2 (en) 2008-01-15 2012-04-17 Shenzhen Skyworth-Rgb Electronic Co., Ltd. Protective device against abnormality for positive and negative dual power supply circuit
CN101577419A (en) * 2009-06-22 2009-11-11 安徽摆客动力技术有限公司 Selflocking direct current supply short circuit protection circuit
CN103647261A (en) * 2013-12-28 2014-03-19 盖洪儒 Portable module protector specially for X-ray machine
CN103647261B (en) * 2013-12-28 2016-06-22 盖洪儒 Portable x-ray machine special module protector
CN106454172A (en) * 2016-12-22 2017-02-22 深圳Tcl数字技术有限公司 Power supply circuit and TV set
CN106454172B (en) * 2016-12-22 2019-11-05 深圳Tcl数字技术有限公司 Power circuit and television set

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