CN2682745Y - Television set with bright spot eliminating circuit as turning off - Google Patents
Television set with bright spot eliminating circuit as turning off Download PDFInfo
- Publication number
- CN2682745Y CN2682745Y CNU2003201197141U CN200320119714U CN2682745Y CN 2682745 Y CN2682745 Y CN 2682745Y CN U2003201197141 U CNU2003201197141 U CN U2003201197141U CN 200320119714 U CN200320119714 U CN 200320119714U CN 2682745 Y CN2682745 Y CN 2682745Y
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- bright spot
- electric capacity
- circuit
- television set
- turning
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Abstract
The utility model relates to the problem of bright spot elimination of the television set as turning off and discloses a television provided with bright spot eliminating circuit as turning off, comprising a vision playing circuit 1, a demoding circuit 2 and a bright spot eliminating circuit as turning off 3. The bright spot eliminating circuit as turning off 3 comprises a charge and discharge unit 4 and a switch unit 5, the charge and discharge unit 4 is used for charging after starting up to make the switch unit 5 cut off and discharging after shutting down to make the switch unit 5 conduct, and the switch unit 5 is used to output current to the vision playing circuit 1 when conducted to make the cathode voltage quickly decrease. When the television set is shut down, the bright spot eliminating circuit works to make the cathode voltage quickly decrease and the electronic beam current in the tube immediately increase, accelerating bombing the phosphor screen and neutralizing the positive and negative load of the high-voltage anode; thus the high voltage is reduced quickly to obtain the purpose of eliminating bright spot.
Description
[technical field]
The utility model relates to a kind of television set, relates in particular to a kind of television set with shutdown spot suppressor.
[background technology]
What the apparent pipe use of television set now was maximum is cathode ray tube, and its imaging process is:
TV filament voltage after shutdown disappears immediately, however negative electrode also have surplus heat, still can emitting electrons; For high pressure, can not obtain immediately discharging, still have the ability that absorbs accelerated electron.Easily cause this moment fluoroscopic subregion, shutdown back still to be bombed, occur bright spot or speck on the screen, picture tube and product quality are had side effects by electron beam.Can find out that by the imaging process of top CRT the bleed off high pressure is to reach the bright effective means that disappears.The more bright mode that disappears of used as television mainly contains following two kinds of patterns at present: the one, improve the cathodic electricity platen press, promptly shutting down moment, make the cathode voltage of picture tube bring up to a bigger positive voltage, dwindle potential difference with anode high voltage, the acceleration of electronics is reduced, reduce the electron number of getting on the phosphor screen.The 2nd, quicken discharge-type, promptly, anode high voltage is descended rapidly shutting down moment.The way of for example taking in high voltage package to increase high pressure bleed off resistance 11 disappears bright, as shown in Figure 1.Can solve the color spot problem though increase bleed off resistance, cost is higher, if lost efficacy not only can not the bleed off high pressure for resistance, also may cause potential safety hazard.
[summary of the invention]
Main purpose of the present utility model provides a kind of television set with the shutdown spot suppressor that can eliminate off-spot safely and effectively.
For achieving the above object, the technical scheme that the utility model proposes is: a kind of television set with shutdown spot suppressor, comprise video amplifier circuit 1, decoding circuit 2 and shutdown spot suppressor 3, and the described shutdown shell dot circuit 3 that disappears comprises:
Charge/discharge unit 4: being used for charging after start ends switch element 5, and discharge makes switch element 5 conductings during shutdown;
Switch element 5: be used for when conducting, exporting video amplifier circuit 1 to and cathode voltage being reduced rapidly.
Described charge/discharge unit 4 comprises: first capacitor C 1 and first resistance R 1 back in parallel, the first termination power VP+, and second end is by just connecing series connection the 3rd capacitor C 3 back ground connection behind the diode D1; Described switch element 5 comprises switch triode Q1, and the base stage of described switch triode Q1 connects second end of first capacitor C 1 and first resistance R, 1 parallel circuits, and emitter links to each other with first end of the 3rd capacitor C 3, and collector electrode links to each other with video amplifier circuit 1.
In order to guarantee not reverse flow of electric current, described switch element 5 can also be to comprise switch triode Q1 and in parallel second and third, four diode D2, D3, D4, the base stage of described switch triode Q1 connects second end of first capacitor C 1 and first resistance R, 1 parallel circuits, emitter links to each other with first end of the 3rd capacitor C 3, and collector electrode links to each other with R, G, the B signal input pin of video amplifier circuit 1 respectively by in parallel second and third, four diode D2, D3, D4.
The beneficial effects of the utility model are: the utility model adopts low-cost and easy circuit to efficiently solve the problem of shutdown color spot.Principle of the present utility model is: start back spot suppressor is not worked, and makes the output of RGB of decoding circuit 2 unaffected.After closing tester in power-down state, spot suppressor work reduces cathode voltage rapidly, the instantaneous increase of electronic beam current in the pipe, and quicken the impact fluorescence screen, in and the positive carry of high-voltage anode, thereby high pressure is descended rapidly, hinder the further emission of electronics, reach the bright purpose that disappears.Owing to do not have the external bleed off circuit of high pressure, so can guarantee safety.
Feature of the present utility model and advantage will be elaborated in conjunction with the accompanying drawings by embodiment.
[description of drawings]
Fig. 1 represents a kind of spot suppressor figure of the prior art;
Fig. 2 represents spot suppressor figure of the present utility model;
Fig. 3 represents the circuit diagram of red primary passage in the video amplifier circuit of the present utility model.
[embodiment]
A kind of execution mode of the present utility model is that described charge/discharge unit 4 comprises: first capacitor C 1 and first resistance R 1 back in parallel, the first termination power VP+, and second end is by just connecing series connection the 3rd capacitor C 3 back ground connection behind the diode D1; Described switch element 5 comprises switch triode Q1, and the base stage of described switch triode Q1 connects second end of first capacitor C 1 and first resistance R, 1 parallel circuits, and emitter links to each other with first end of the 3rd capacitor C 3, and collector electrode links to each other with video amplifier circuit 1.
Be illustrated in figure 2 as another kind of preferred forms of the present utility model, described charge/discharge unit 4 comprises: first capacitor C 1 and first resistance R, the 1 back first termination power VP+ in parallel, second end is by just connecing series connection the 3rd capacitor C 3 back ground connection behind the diode D1, second capacitor C, 2 one ends link to each other with second end of first capacitor C 1 with first resistance R, 1 parallel circuits, other end ground connection, the negative pole of catching diode ZD links to each other with second end of first capacitor C 1 with first resistance R, 1 parallel circuits, plus earth, catching diode ZD guarantees that shutdown snap switch triode Q1 collector voltage is unlikely too high, in order to avoid the decoding block of breaking; Second capacitor C 2 filtering over the ground; In order to guarantee not reverse flow of electric current, described switch element 5 is designed to comprise the unit of switch triode Q1 and in parallel second and third, four diode D2, D3, D4, the base stage of described switch triode Q1 connects second end of first capacitor C 1 and first resistance R, 1 parallel circuits, emitter links to each other with first end of the 3rd capacitor C 3, and collector electrode links to each other with R, G, the B signal input pin of video amplifier circuit 1 respectively by in parallel second and third, four diode D2, D3, D4.Its operation principle is: power supply VP+ in start back begins to capacitor C 1, the C3 charging, and this moment, the base voltage of switch triode Q1 was higher than emitter voltage, and switch triode Q1 ends, and does not influence the output channel of the RGB of decoding circuit 2.After closing tester in power-down state, the VP+ loss of voltage, capacitor C 1 is by resistance R 1 and VP+ load discharge, the base voltage of switch triode Q1 reduces fast, the first diode D1 guarantees that oppositely the voltage on the capacitor C 3 is higher than the base voltage of switch triode Q1 in this process, switch triode Q1 conducting, collector electrode produces an instant high-voltage, make the triode Q5 conducting in the video amplifier circuit 1, also conducting of triode Q6 and Q7, as shown in Figure 1, the emitter of the emitter of NPN triode Q6 and PNP triode Q7 exports the cathode voltage utmost point to, cathode voltage is reduced rapidly, the instantaneous increase of electronic beam current in the pipe, and quicken the impact fluorescence screen, in and the positive carry of high-voltage anode, thereby high pressure is descended rapidly, hinder the further emission of electronics, reach the bright purpose that disappears.
Compare with other the brightening circuit that disappears, the utility model is simple and easy to implement, and can eliminate off-spot effectively.
Claims (3)
1. the television set with shutdown spot suppressor comprises video amplifier circuit (1), decoding circuit (2) and shutdown spot suppressor (3), and it is characterized in that: described shutdown spot suppressor (3) comprising:
Charge/discharge unit (4): being used for charging after start ends switch element (5), and discharge makes switch element (5) conducting during shutdown;
Switch element (5): be used for when conducting, exporting video amplifier circuit (1) to and cathode voltage being reduced rapidly.
2. the television set with shutdown spot suppressor as claimed in claim 1 is characterized in that:
Described charge/discharge unit (4) comprising: first electric capacity (C1) back in parallel, first termination power (VP+) with first resistance (R1), and second end is by just connecing diode (D1) back series connection the 3rd electric capacity (C3) back ground connection;
Described switch element (5) comprises switch triode (Q1), the base stage of described switch triode (Q1) connects second end of first electric capacity (C1) and first resistance (R1) parallel circuits, emitter links to each other with first end of the 3rd electric capacity (C3), and collector electrode links to each other with video amplifier circuit (1).
3. the television set with shutdown spot suppressor as claimed in claim 1 is characterized in that:
Described charge/discharge unit (4) comprising: first electric capacity (C1) back in parallel, first termination power (VP+) with first resistance (R1), and second end is by just connecing diode (D1) back series connection the 3rd electric capacity (C3) back ground connection;
Described switch element (5) comprises switch triode (Q1) and in parallel second and third, four diodes (D2, D3, D4), the base stage of described switch triode (Q1) connects second end of first electric capacity (C1) and first resistance (R1) parallel circuits, emitter links to each other with first end of the 3rd electric capacity (C3), and collector electrode links to each other with R, G, the B signal input pin of video amplifier circuit (1) respectively by in parallel second and third, four diodes (D2, D3, D4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2003201197141U CN2682745Y (en) | 2003-12-26 | 2003-12-26 | Television set with bright spot eliminating circuit as turning off |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2003201197141U CN2682745Y (en) | 2003-12-26 | 2003-12-26 | Television set with bright spot eliminating circuit as turning off |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2682745Y true CN2682745Y (en) | 2005-03-02 |
Family
ID=34599608
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2003201197141U Expired - Fee Related CN2682745Y (en) | 2003-12-26 | 2003-12-26 | Television set with bright spot eliminating circuit as turning off |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2682745Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1937706B (en) * | 2006-06-30 | 2011-05-11 | 康佳集团股份有限公司 | Television receiver off-spot removing method and control device |
| CN105959600A (en) * | 2016-06-29 | 2016-09-21 | 重庆惠科金扬科技有限公司 | Circuit capable of quickly turning off TV indicator lamp after power off, and television |
-
2003
- 2003-12-26 CN CNU2003201197141U patent/CN2682745Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1937706B (en) * | 2006-06-30 | 2011-05-11 | 康佳集团股份有限公司 | Television receiver off-spot removing method and control device |
| CN105959600A (en) * | 2016-06-29 | 2016-09-21 | 重庆惠科金扬科技有限公司 | Circuit capable of quickly turning off TV indicator lamp after power off, and television |
| CN105959600B (en) * | 2016-06-29 | 2023-04-07 | 重庆惠科金扬科技有限公司 | Circuit for quickly turning off TV indicator lamp after power failure and television |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050302 Termination date: 20100126 |