CN201075824Y - Antenna feeding circuit - Google Patents
Antenna feeding circuit Download PDFInfo
- Publication number
- CN201075824Y CN201075824Y CNU2007200266299U CN200720026629U CN201075824Y CN 201075824 Y CN201075824 Y CN 201075824Y CN U2007200266299 U CNU2007200266299 U CN U2007200266299U CN 200720026629 U CN200720026629 U CN 200720026629U CN 201075824 Y CN201075824 Y CN 201075824Y
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Abstract
The utility model discloses an antenna power supply circuit. The inside of a video receiving device connected with the antenna comprises a power source and a processor. A switch circuit is connected between the power source and the power supply end of the antenna. The control end of the switch circuit receives a switch control signal transmitted by the processor. A switch access is connected between the power source and the power supply end of the antenna. The processor determines the state of high and low levels of the switch control signal outputted by the processor according to a command of a user that whether to select to supply power to the antenna or not; thereby controlling the conduction of the switch circuit when needing to supply power to the antenna to realize to supply power to the antenna by the power source. The utility model not only meets the power supply requirements of various antennas of the existing European market, increases the universality of television products; simultaneously, by adopting the method that the television controls whether to supply power to the outside antenna or not, the utility model leads the television to reach best receiving for a DVB-T signal and is suitable for being used by a normal user or under a special situation.
Description
Technical field
The utility model belongs to the power supply circuits technical field, specifically, relates to the antenna power supply circuits that a kind of exterior antenna for video reception apparatus such as digital intergrated unit, television sets provides power supply.
Background technology
DVB-T is based on the digital video broadcast system of terrestrial wireless transmission means.In Europe, because the region reason generally adopts the DVB-T digital television system, still, for the DVB-T system, multipath interference that causes owing to reasons such as landform etc. can cause the decay of signal.Arrived remote districts, if signal too a little less than, just can't normally watch the program of some channel.In Europe, the transmission means of DVB-T is the first-selection of Digital Television, and the sort signal transmission means needs transmitting base station emission DVB-T signal, can directly receive this signal as the television set of receiver.But receiver directly influences the intensity of received signal from the distance of transmitting base station, often need to increase an active antenna for the more weak place of signal, this is no problem for normal resident family, but be applied to some special environment, such as open-air vacation land, yacht etc., the power supply of antenna just becomes the problem of difficulty.Based on this, the antenna that has the signal enhancement function on the market arises at the historic moment.
On the European market, the part antenna needs extraneous to its power supply, and power supply will be transmitted by radio frequency line.At present, the tuner of tuner producer release also possesses the condition that can realize this function.Certainly, also there are some antennas not need extraneous power supply, at this time,, cause the decline of sensitivity if, then can have influence on the intensity of signal still to its power supply, so, realize power supply as required according to the actual demand of antenna.
The utility model content
The purpose of this utility model has been to provide a kind of novel antenna power supply circuits, to solve the powerup issue as required of antenna.
For solving the problems of the technologies described above, the utility model is achieved by the following technical solutions:
A kind of antenna power supply circuits include a power supply and processor in the video reception apparatus inside that connects described antenna; Be connected with a switching circuit between the feeder ear of described power supply and antenna, the control end of described switching circuit receives the switch controlling signal that described processor sends, and switch ways is connected between the feeder ear of described power supply and antenna.Described processor is selected whether to determine the high-low level state of the switch controlling signal of its output to the instruction of antenna power supply, and then control described switching circuit conducting when needs are powered to antenna according to the user, is realized the power supply of described power supply to antenna.
Further, in described switching circuit, include a NPN type triode and a P channel MOS tube, the base stage of described NPN type triode connects the switch controlling signal output of described processor, grounded emitter, collector electrode connects described power supply on the one hand, connects the grid of described P channel MOS tube on the other hand; The source electrode of described P channel MOS tube connects described power supply, and drain electrode connects the feeder ear of described antenna.
Certainly, described switching circuit also can adopt a NPN type triode and a positive-negative-positive triode to be formed by connecting, the base stage of described NPN type triode connects the switch controlling signal output of described processor, grounded emitter, collector electrode connects described power supply on the one hand, connects the base stage of described positive-negative-positive triode on the other hand; The emitter of described positive-negative-positive triode connects described power supply, and collector electrode connects the feeder ear of described antenna.
Can effectively protect the internal circuit of video reception apparatus when externally short trouble appears in antenna, the feeder ear of described antenna connects the switch ways of described switching circuit by a short-circuit protection circuit.
Wherein, described short-circuit protection circuit can be made of a resettable fuse, and the feeder ear of described antenna connects the switch ways of described switching circuit by described resettable fuse; Perhaps design a recoverable current-limiting protection resistance in described short-circuit protection circuit, the feeder ear of described antenna connects the switch ways of described switching circuit by described current-limiting protection resistance; Be connected the negative electrode of a voltage stabilizing didoe, the plus earth of described voltage stabilizing didoe with the connected node place of described switching circuit at described current-limiting protection resistance.
Further again, in described video reception apparatus, include a tuner, the switch ways of described switching circuit is connected between the voltage output pin of described power supply and tuner, and the voltage output pin of described tuner connects the feeder ear of described antenna by the radio frequency cable.
Further again, the voltage output pin of described tuner connects wherein one road input of described processor, described processor is controlled the operating state of connected warning circuit according to the high low-potential state of described input, and then is implemented in and sends the indication of reporting to the police when short trouble appears in exterior antenna.
Further, the input at described processor is connected with a voltage clamping circuit.
Compared with prior art, advantage of the present utility model and good effect are: antenna power supply circuits of the present utility model provide direct current supply by the video reception apparatus internal electric source to extraneous antenna, not only satisfy the power reguirements of various antenna on the present European market, strengthened the versatility of tv product; Simultaneously, the method by whether this television set control exterior antenna powers makes television set can realize optimum reception to the signal of DVB-T, is adapted at normal resident family or use in particular cases.
After reading the detailed description of the utility model execution mode in conjunction with the accompanying drawings, other characteristics of the present utility model and advantage will become clearer.
Description of drawings
Fig. 1 is the circuit theory diagrams of a kind of embodiment of the antenna power supply circuits that propose of the utility model;
Fig. 2 is the circuit theory diagrams of the another kind of embodiment of the antenna power supply circuits that propose of the utility model.
Embodiment
Below in conjunction with accompanying drawing embodiment of the present utility model is done explanation in further detail.
The utility model is by increasing the power supply circuits with switching function between the internal electric source of television set and extraneous antenna, from the whole set of television circuit, take out the power supply of a direct current+5V, these power supply circuits of process output to the special pin (such as the voltage output pin) of tuner, and then by feeder line active antenna are powered.Power supply circuits must have the current-limiting protection function, and this point is very important, because antenna operating position complexity, faults such as short circuit appear in antenna end probably, if there is not current-limiting protection, may cause damage to television set itself.Realize the function of foregoing circuit, also require employed tuner to have the function pin of DC power supply power supply.
Embodiment one, referring to shown in Figure 1, be connected television set internal electric source+5V_TUNER in the present embodiment and cooperate peripheral circuit to be formed by connecting with switching circuit between the extraneous antenna by a NPN type triode Q44 and a P channel MOS tube Q45.Wherein, the base stage of described NPN type triode Q44 is connected the switch controlling signal output of described processor with the potential-divider network of being made of resistance R 979, R981 by filter capacitor C65, described output can selection processor wherein one road GPIO cause for gossip existing, such as the GPIO_4 among Fig. 1, certainly, also can select for use the port of other exportable high-low level signal of processor to realize that present embodiment does not specifically limit this.The grounded emitter of NPN type triode Q44, collector electrode connect the grid of described P channel MOS tube Q45 on the one hand by resistance R 49, and by capacitor C 41 ground connection; Connect described P channel MOS tube Q45 source electrode by resistance R 37 on the other hand.The source electrode of described P channel MOS tube Q45 is connected described DC power supply+5V_TUNER via inductance L 72 with the LC filter network that capacitor C 61, C191 form simultaneously, drain electrode connects the voltage output pin V_ANT of television tuner through a resettable fuse F1, and then connect extraneous antenna by the radio frequency cable, when extraneous active antenna need be powered, for it provides operating voltage.
Here, adopting P channel MOS tube Q45 composition power supply+5V_TUNER is because the conduction voltage drop of P channel MOS tube is low to the switch ways of antenna, can be so that unlikely too low by the voltage of V_ANT end output, and can have big electric current to flow through, guarantee the power reguirements of extraneous antenna.
Its operation principle is: in the custom menu of television set the inside an ANTENNA POWER option is set, when the user chose this option, the set handling device made its GPIO_4 mouth output high level, and at this moment, triode Q44 conducting drags down the grid potential of metal-oxide-semiconductor Q45.Described P channel MOS tube Q45 is because its source voltage is higher than its grid voltage and conducting, and then be communicated with the supply access of described DC power supply+5V_TUNER to antenna, be that V_ANT is 5V, extraneous antenna obtains direct current supply, thereby the gain that can realize signal is amplified, and improves the sensitivity of tv product received signal with this.And when the DVB-T of base station signal is strong, then not needing provides extra power supply to extraneous antenna, at this moment, the user can make it be in not selected state by the method for revising ANTENNA POWER option, at this moment, processor is changed to low level with its GPIO_4 mouth, control triode Q44 ends, and then the source voltage that makes P channel MOS tube Q45 equals its grid voltage and ends, cut off the supply access of DC power supply+5V_TUNER to antenna, this moment, the V_ANT end did not have voltage output, the normal received RF signal of antenna.
Because it is open interface that tuner connects the port of antenna, short circuit phenomenon probably appears in extraneous antenna end, cause the damage of television set internal circuit for fear of antenna short circuit, a resettable fuse F1 connects between the voltage output pin V_ANT of the drain electrode of described P channel MOS tube Q45 and tuner, when short trouble took place, V_ANT held shorted to earth, caused to flow through the last immediate current change of fuse F1 greatly, with its fusing, make that television set internal circuit and antenna are unlikely to cause damage.And after short trouble was eliminated, fuse F1 replied voluntarily, to guarantee the realization of above-mentioned functions under the normal condition.
Embodiment two, and referring to shown in Figure 2, present embodiment has been enumerated the another kind of way of realization of switching circuit, comprise a NPN type triode Q60 and a positive-negative-positive triode Q61 and connected peripheral circuit.The switch controlling signal output GPIO_4 of processor is connected the base stage of described NPN type triode Q60 with filter capacitor C600 by divider resistance R951～R953, the emitter of described NPN type triode Q60 is by resistance R 954 ground connection, collector electrode connects DC power supply+5V_TUNER by resistance R 949 on the one hand, connects the base stage of described positive-negative-positive triode Q61 on the other hand.The transmitter of described positive-negative-positive triode Q61 connects described DC power supply+5V_TUNER; collector electrode is by being connected filter network (described in the present embodiment filter network specifically is made up of resistance R 950, inductance L 76 and capacitor C 467, C468) by recoverable current-limiting protection resistance F2 with the current-limiting protection circuit that voltage stabilizing didoe D18 forms; and then connect the voltage output pin V_ANT of television tuner, and then connect extraneous antenna by the radio frequency cable through described filter network.
In order when short trouble appears in extraneous antenna, to point out by the television set output alarm, also design has monitoring circuit in the switching circuit of present embodiment, as shown in Figure 2, the GPIO_5 port by processor is formed by connecting with the resistance pressure-dividing network that bidirectional diode D164 and R955, R956 form.Certainly, described GPIO_5 port also can adopt other input port of processor to realize that the utility model is not limited thereto.
Its operation principle and embodiment one are similar: under default situations, the GPIO_4 port of configuration processor is a low level, and then blocking-up DC power supply+5V_TUNER is to the power supply of antenna.And need provide when power supply to extraneous antenna as the user, and processor is by its GPIO_4 port output high level, control triode Q60, Q61 conducting, and then be communicated with the supply access of DC power supply+5V_TUNER to antenna, to guarantee the operate as normal of extraneous antenna.Meanwhile, detect the electric power thus supplied of antenna by the GPIO_5 port of processor, if receive high level signal, then antenna is working properly; And when short circuit appearred in antenna end, current-limiting protection resistance F2 disconnected, and cut off the supply access of DC power supply+5V_TUNER and antenna, the V_ANT terminal potential was put low, avoided damage with protection television set internal circuit.At this moment, because GPIO_5 port current potential step-down, processor judges that according to its internal logic this moment, short trouble appearred in antenna end, and then controls connected warning circuit output alarm, notes with the prompting user.
In the present embodiment, bidirectional diode D164 can play the effect of voltage clamping in circuit, plays good filtering effect for the interference signal of being introduced by the external world.
Certainly, be not limited in the form of above-mentioned two kinds of embodiment at the switching circuit described in the utility model, other has the components and parts of on-off action or realizes that by its circuit of forming the utility model is not limited thereto also can to adopt CMOS pipe or relay, switch chip etc.
In addition, the circuit with short-circuit protection function also is not limited in two kinds of versions shown in the embodiment one, two, and other circuit structure with short-circuit protection effect equally also can be applied in the above-mentioned antenna power supply circuits.
The utility model is by adopting above-mentioned simple circuit configuration, can solve the problem of antenna power supply effectively, guarantee that antenna can carry out the gain amplification of signal, thereby improved the signal sensitivity of television set greatly, making and can watch stronger TV signal under particular surroundings, also is to select very easily for normal resident.Certainly, this circuit structure equally also applicable to as digital all-in-one etc. have in other video reception apparatus of antenna system.
Should be noted that; above-mentioned explanation is not to be to restriction of the present utility model; the utility model also is not limited in above-mentioned giving an example; variation, remodeling, interpolation or replacement that those skilled in the art are made in essential scope of the present utility model also should belong to protection range of the present utility model.
Claims (10)
1. antenna power supply circuits include a power supply and processor in the video reception apparatus inside that connects described antenna; It is characterized in that: be connected with a switching circuit between the feeder ear of described power supply and antenna, the control end of described switching circuit receives the switch controlling signal that described processor sends, and switch ways is connected between the feeder ear of described power supply and antenna.
2. antenna power supply circuits according to claim 1, it is characterized in that: in described switching circuit, include a NPN type triode and a P channel MOS tube, the base stage of described NPN type triode connects the switch controlling signal output of described processor, grounded emitter, collector electrode connects described power supply on the one hand, connects the grid of described P channel MOS tube on the other hand; The source electrode of described P channel MOS tube connects described power supply, and drain electrode connects the feeder ear of described antenna.
3. antenna power supply circuits according to claim 1, it is characterized in that: in described switching circuit, include a NPN type triode and a positive-negative-positive triode, the base stage of described NPN type triode connects the switch controlling signal output of described processor, grounded emitter, collector electrode connects described power supply on the one hand, connects the base stage of described positive-negative-positive triode on the other hand; The emitter of described positive-negative-positive triode connects described power supply, and collector electrode connects the feeder ear of described antenna.
4. according to claim 1 or 2 or 3 described antenna power supply circuits, it is characterized in that: the feeder ear of described antenna connects the switch ways of described switching circuit by a short-circuit protection circuit.
5. antenna power supply circuits according to claim 4 is characterized in that: include a resettable fuse in described short-circuit protection circuit, the feeder ear of described antenna connects the switch ways of described switching circuit by described resettable fuse.
6. antenna power supply circuits according to claim 4 is characterized in that: include a recoverable current-limiting protection resistance in described short-circuit protection circuit, the feeder ear of described antenna connects the switch ways of described switching circuit by described current-limiting protection resistance.
7. antenna power supply circuits according to claim 6 is characterized in that: be connected the negative electrode of a voltage stabilizing didoe, the plus earth of described voltage stabilizing didoe with the connected node place of described switching circuit at described current-limiting protection resistance.
8. antenna power supply circuits according to claim 4, it is characterized in that: in described video reception apparatus, include a tuner, the switch ways of described switching circuit is connected between the voltage output pin of described power supply and tuner, and the voltage output pin of described tuner connects the feeder ear of described antenna by the radio frequency cable.
9. antenna power supply circuits according to claim 8, it is characterized in that: the voltage output pin of described tuner connects wherein one road input of described processor, and described processor is controlled the operating state of connected warning circuit according to the high low-potential state of described input.
10. antenna power supply circuits according to claim 9 is characterized in that: the input at described processor is connected with a voltage clamping circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200266299U CN201075824Y (en) | 2007-08-14 | 2007-08-14 | Antenna feeding circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200266299U CN201075824Y (en) | 2007-08-14 | 2007-08-14 | Antenna feeding circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201075824Y true CN201075824Y (en) | 2008-06-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007200266299U Expired - Fee Related CN201075824Y (en) | 2007-08-14 | 2007-08-14 | Antenna feeding circuit |
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| CN (1) | CN201075824Y (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103179458A (en) * | 2013-03-25 | 2013-06-26 | 深圳市九洲电器有限公司 | Set-top box and antenna power supply module thereof |
| CN106961565A (en) * | 2017-03-17 | 2017-07-18 | 安徽波维电子科技有限公司 | A kind of tuner of the intelligent information prompting based on DSP single-chip microcomputers |
| CN108226690A (en) * | 2016-12-21 | 2018-06-29 | 国家无线电监测中心检测中心 | Detection circuit |
| CN108873722A (en) * | 2018-08-01 | 2018-11-23 | 合肥阅辞科技有限公司 | Wireless intelligent house managing and control system |
| CN109935950A (en) * | 2018-08-29 | 2019-06-25 | 浙江科比特科技有限公司 | A kind of antenna feeding circuit and antenna |
| CN110471342A (en) * | 2019-08-16 | 2019-11-19 | 惠州Tcl移动通信有限公司 | Method for controlling power supply, computer storage medium and the mobile terminal of NFC antenna |
| CN111244607A (en) * | 2015-02-11 | 2020-06-05 | 康普技术有限责任公司 | Module, system and method for power delivery to remote radio heads |
| US11256277B2 (en) | 2014-02-17 | 2022-02-22 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11294409B2 (en) | 2014-02-17 | 2022-04-05 | Commscope Technologies Llc | Methods and equipment for reducing power loss in cellular systems |
| US11333695B2 (en) | 2014-02-17 | 2022-05-17 | Commscope Technologies Llc | Methods and equipment for reducing power loss in cellular systems |
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2007
- 2007-08-14 CN CNU2007200266299U patent/CN201075824Y/en not_active Expired - Fee Related
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103179458A (en) * | 2013-03-25 | 2013-06-26 | 深圳市九洲电器有限公司 | Set-top box and antenna power supply module thereof |
| CN103179458B (en) * | 2013-03-25 | 2016-04-20 | 深圳市九洲电器有限公司 | A kind of Set Top Box and antenna supply module thereof |
| US11669118B2 (en) | 2014-02-17 | 2023-06-06 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11662759B2 (en) | 2014-02-17 | 2023-05-30 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11740645B2 (en) | 2014-02-17 | 2023-08-29 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11726508B2 (en) | 2014-02-17 | 2023-08-15 | Commscope Technologies Llc | Methods and systems for determining resistance of power conductors |
| US11675382B2 (en) | 2014-02-17 | 2023-06-13 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11675381B2 (en) | 2014-02-17 | 2023-06-13 | Commscope Technologies Llc | Apparatuses and related methods for reducing power loss |
| US11669117B2 (en) | 2014-02-17 | 2023-06-06 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11256277B2 (en) | 2014-02-17 | 2022-02-22 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11275395B2 (en) | 2014-02-17 | 2022-03-15 | Commscope Technologies Llc | Programmable power supplies for cellular base stations and related methods of reducing power loss in cellular systems |
| US11294409B2 (en) | 2014-02-17 | 2022-04-05 | Commscope Technologies Llc | Methods and equipment for reducing power loss in cellular systems |
| US11333695B2 (en) | 2014-02-17 | 2022-05-17 | Commscope Technologies Llc | Methods and equipment for reducing power loss in cellular systems |
| CN111244607A (en) * | 2015-02-11 | 2020-06-05 | 康普技术有限责任公司 | Module, system and method for power delivery to remote radio heads |
| CN111244607B (en) * | 2015-02-11 | 2021-05-04 | 康普技术有限责任公司 | Module, system and method for power delivery to remote radio heads |
| CN108226690A (en) * | 2016-12-21 | 2018-06-29 | 国家无线电监测中心检测中心 | Detection circuit |
| CN106961565A (en) * | 2017-03-17 | 2017-07-18 | 安徽波维电子科技有限公司 | A kind of tuner of the intelligent information prompting based on DSP single-chip microcomputers |
| CN108873722A (en) * | 2018-08-01 | 2018-11-23 | 合肥阅辞科技有限公司 | Wireless intelligent house managing and control system |
| CN109935950A (en) * | 2018-08-29 | 2019-06-25 | 浙江科比特科技有限公司 | A kind of antenna feeding circuit and antenna |
| CN109935950B (en) * | 2018-08-29 | 2024-03-15 | 浙江科比特科技有限公司 | Antenna power supply circuit and antenna |
| CN110471342A (en) * | 2019-08-16 | 2019-11-19 | 惠州Tcl移动通信有限公司 | Method for controlling power supply, computer storage medium and the mobile terminal of NFC antenna |
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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: 20080618 Termination date: 20110814 |