CN202190337U

CN202190337U - Audio-video signal processing circuit and television

Info

Publication number: CN202190337U
Application number: CN2011202706020U
Authority: CN
Inventors: 王同鲁; 闫荣; 张国庆
Original assignee: RIZHAO HIDEAR ELECTRICAL CO Ltd
Current assignee: RIZHAO HIDEAR ELECTRICAL CO Ltd
Priority date: 2011-07-28
Filing date: 2011-07-28
Publication date: 2012-04-11
Anticipated expiration: 2021-07-28

Abstract

The utility model discloses an audio-video signal processing circuit and a television. The audio-video signal processing circuit comprises a tuner, a single-SWA (Surface Acoustic Wave) circuit and a master chip capable of separating and processing audio-video mixed signals, wherein the tuner receives a television signal, converts the received television signal into an intermediate-frequency signal and transmits the intermediate-frequency signal to the single-SWA circuit; and the single-SWA circuit filters the received intermediate-frequency signal to obtain an audio-video mixed signal, transmits the audio-video mixed signal to the master chip for separation and processing. In the utility model, the single-SWA circuit replaces a traditional double-SWA circuit, and is used together with the master chip capable of separating the mixed audio-video signal to build the audio-video signal processing circuit, so that an SWA circuit is omitted for circuit design, the circuit structure is simpler, and the hardware cost is lowered. The audio-video signal processing circuit is particularly applicable to household appliances with relatively fierce price competition, such as televisions, set-top boxes and other audio-video receiving equipment, so that the complete machine cost of the household appliances is further effectively controlled.

Description

A kind of audio-video signal treatment circuit and television set

Technical field

The utility model belongs to the signal processing circuit technical field, specifically, and the television set that relates to a kind of circuit design technique that the Voice & Video signal is received and handles and adopt said audio-video signal treatment circuit design.

Background technology

In present system for TV set, generally all dispose circuit parts such as tuner, alliteration watch circuit, master chip.Wherein, tuner is used to receive the radio television signal that TV station sends, and after it is carried out demodulation, generates intercarrier signal and exports the alliteration watch circuit to and handle.The mixed signal that in the intercarrier signal of tuner output, includes Voice & Video after carrying out Filtering Processing through the alliteration watch circuit, is filtered outputting video signal from a sound watch circuit, from another one sound watch circuit, filter output audio signal.Audio signal after the separation and vision signal transfer to master chip respectively and decode and the convergent-divergent processing, drive loud speaker and display screen broadcast TV programme through audio frequency output channel and video output channel respectively then, to satisfy the users for watching demand.

Since in present TV receiving system, need to use two sound watch circuits to come the intercarrier signal of tuner output is carried out the filtering separating treatment, therefore, the circuit design relative complex, hardware cost is higher, is unfavorable for promoting the market competitiveness of tv product.

Summary of the invention

The purpose of the utility model is to provide a kind of audio-video signal treatment circuit that adopts the design of monophone table, to simplify circuit structure, reduces hardware cost.

For solving the problems of the technologies described above, the utility model adopts following technical scheme to be achieved:

A kind of audio-video signal treatment circuit comprises tuner, monophone watch circuit and audio-video mixed signal is had and separates and the master chip of processing capacity; Said tuner received television signal; And convert intermediate-freuqncy signal to and transfer to described monophone watch circuit; Said monophone watch circuit carries out Filtering Processing to the intermediate-freuqncy signal that receives, and the mixed signal that filters out Voice & Video transfers to master chip and separates and handle.

Further, after handling through an amplifying circuit through the intermediate-freuqncy signal of said tuner output, transfer to described monophone watch circuit again.

Preferably; In said amplifying circuit, include a NPN type triode; The base stage of said triode connects the intermediate-freuqncy signal output of tuner through capacitance; Collector electrode connects DC power supply through current-limiting resistance on the one hand, connects the input of monophone watch circuit on the other hand through another capacitance, and the grounded emitter of said triode is perhaps through another current-limiting resistance ground connection.

In order to reduce electromagnetic interference, said amplifying circuit preferred cloth is located at the position of closing on tuner on the pcb board.

Further again, after said monophone watch circuit carried out filtration treatment to the intermediate-freuqncy signal that receives, the mixed signal through its two lead-out terminal output difference form transferred to described master chip.

Preferably, between two lead-out terminals of said monophone watch circuit, be parallel with an inductance, two lead-out terminals connect described master chip through the capacitance of a series connection separately.

Consideration from Electro Magnetic Compatibility EMC preferably is laid in the position of closing on master chip on the pcb board with said monophone watch circuit.

Further again, in said audio-video signal treatment circuit, also include the voltage stabilizing circuit that is used to change the required operating voltage of generation tuner, said voltage stabilizing circuit preferred cloth is located at the position of closing on tuner on the pcb board, to reduce electromagnetic interference.

Further, said master chip output intermediate-frequency gain control signal after rc filter circuit is handled, transfers to the intermediate-frequency gain signal input end of said tuner; Said rc filter circuit is laid in the position of closing on tuner on the pcb board, to satisfy the EMC requirement.

Based on above-mentioned audio-video signal treatment circuit structure; The utility model also provides a kind of television set that adopts the design of said audio-video signal treatment circuit, comprises tuner, monophone watch circuit and audio-video mixed signal had separating and the master chip of processing capacity; Said tuner received television signal; And convert intermediate-freuqncy signal to and transfer to described monophone watch circuit; Said monophone watch circuit carries out Filtering Processing to the intermediate-freuqncy signal that receives, and the mixed signal that filters out Voice & Video transfers to master chip and separates and handle.

Compared with prior art; The advantage and the good effect of the utility model are: the utility model adopts the monophone watch circuit to replace traditional alliteration watch circuit; Cooperate to have and separate the master chip structure audio-video signal treatment circuit that mixes the audio-video signal function, thereby on circuit design, can save a sound watch circuit, circuit structure is simpler; Hardware cost is minimized; Especially be fit to be applied in the fierce relatively household appliances of price competition, for example in audio frequency and video such as television set, the STB receiving equipment, and then make the complete machine cost of household appliances be effectively controlled.

After the detailed description in conjunction with advantages the utility model execution mode, other characteristics of the utility model and advantage will become clearer.

Description of drawings

Fig. 1 is the circuit theory diagrams of a kind of embodiment of the audio-video signal treatment circuit medium-high frequency head that proposes of the utility model and peripheral circuit thereof;

Fig. 2 is the circuit theory diagrams of a kind of embodiment of voltage stabilizing circuit in the audio-video signal treatment circuit that proposes of the utility model;

Fig. 3 is the circuit theory diagrams of a kind of embodiment of monophone watch circuit in the audio-video signal treatment circuit that proposes of the utility model.

Embodiment

Describe in detail below in conjunction with the embodiment of accompanying drawing the utility model.

Embodiment one, and present embodiment is example with the television set, in conjunction with Fig. 1 to Fig. 3 the concrete establishment structure and the operation principle thereof of said audio-video signal treatment circuit set forth in detail.

Continuous development along with integrated circuit technique; The master chip that audio-video signal is carried out decoding processing has been endowed more function, is that master chips such as MSP6M48, MSP6M182 and MSD318, MSD306 have all possessed the function of audio-video mixed signal being carried out separating treatment such as model.In conjunction with this master chip, present embodiment has proposed a kind of audio-video signal treatment circuit based on the monophone table, to reach the simplification circuit design, reduces the purpose of hardware cost.

The audio-video signal treatment circuit of present embodiment mainly has by tuner U12, monophone watch circuit U6 and to audio-video mixed signal and separates and the master chip of processing capacity is formed, referring to Fig. 1, shown in Figure 3.Wherein, tuner U12 is used to receive the radio television signal that TV station sends, and after it is carried out demodulation process, generates the intermediate-freuqncy signal IF_TV that includes Voice & Video, exports monophone watch circuit U6 to and carries out filtration treatment.As a kind of preferred design of present embodiment, after carrying out power amplification and handle through one-level amplifying circuit A earlier through the intermediate-freuqncy signal IF_TV of tuner U12 output being preferred, transfer to described monophone watch circuit U6 again.As shown in Figure 3, said amplifying circuit A can cooperate peripheral circuit to build by one road NPN type triode Q408.Wherein, Intermediate-freuqncy signal IF_TV through tuner U12 output is at first after the capacitance C466 that connects isolates out flip-flop wherein; Transfer to the base stage of said triode Q408 again through the current-limiting resistance R452 of series connection, be used for triode Q408 is carried out break-make control.The base stage of said triode Q408 connects DC power supply 12VA through the potential-divider network of being made up of resistance R 418, R450 simultaneously; Grounded emitter or current-limiting resistance R449 ground connection through connecting; Collector electrode connects DC power supply 12VA through current-limiting resistance R451 on the one hand, on the other hand through be connected the input IN of monophone watch circuit U6 with the series arm that capacitance C473 forms by resistance R 460.Said monophone watch circuit U6 carries out Filtering Processing to the intermediate-freuqncy signal that receives, and filters out the mixed signal of Voice & Video wherein, and with the form of differential signal VIFM, VIFP; Through its two lead-out terminal OUT1, OUT2 output; Transfer to the mixed signal input of master chip, utilize master chip to isolate wherein audio signal and vision signal, and decode handle with convergent-divergent after; Transfer to audio frequency output channel and video output channel respectively; And then drive the sound accompaniment of loud speaker output program respectively, through display screen output television image, accomplish the function that displays the play of TV programme.

As a kind of preferred design of present embodiment, also be designed with filter circuit at the output of said monophone watch circuit U6, can connect to form by inductance L 44 and two capacitance C88, C94, as shown in Figure 3.Wherein, Inductance L 44 is connected in parallel between two the lead-out terminal OUT1, OUT2 of monophone watch circuit U6; Two capacitance C88, C94 are in series with two lead-out terminal OUT1, the OUT2 of monophone watch circuit U6 respectively; Be used for filtering out the noise signal of mixed signal, the mixed signal that guarantees to transfer to master chip is pure.

For the required operating voltage 5V_B1 of tuner U12; Can provide by the voltage stabilizing circuit conversion that pressurizer U28 cooperates simple peripheral circuit (for example capacitor C 310, C258, C278 and inductance L 100 etc.) to form; Referring to shown in Figure 2; Its input can connect described DC power supply 12VA, and output connects the power end VCC of tuner U12, for tuner U12 provides+direct-current working volts of 5V.

The intermediate-frequency gain control signal IF_AGC required for tuner U12 work can be provided by master chip output; After carrying out Filtering Processing through the rc filter circuit of forming by resistance R 414 and capacitor C 471; Transfer to the intermediate-frequency gain signal input end IF AGC of tuner U12, referring to shown in Figure 1.

From the Electro Magnetic Compatibility EMC of television set pcb board is considered, present embodiment preferably is laid on the said pcb board position near tuner U12 with rc filter circuit R414 shown in Figure 1, C471, voltage stabilizing circuit shown in Figure 2 and amplifying circuit A shown in Figure 3; Monophone watch circuit U6 and peripheral circuit B thereof part (as shown in Figure 3) then preferred cloth is located on the pcb board position near master chip, to reduce electromagnetic interference.

Present embodiment adopts the monophone table to replace traditional alliteration table to set up the audio-video signal treatment circuit, and is simple in structure, development efficiency is high, is adapted at television set, STB etc. and has audio-video signal and receive in the electronic product of disposal ability and apply.

Certainly; The above only is a kind of preferred implementation of the utility model, for those skilled in the art, under the prerequisite that does not break away from the utility model principle; Can also make some improvement and retouching, these improvement and retouching also should be regarded as the protection range of the utility model.

Claims

1. audio-video signal treatment circuit is characterized in that: comprise tuner, monophone watch circuit and audio-video mixed signal had and separate and the master chip of processing capacity; Said tuner received television signal; And convert intermediate-freuqncy signal to and transfer to described monophone watch circuit; Said monophone watch circuit carries out Filtering Processing to the intermediate-freuqncy signal that receives, and the mixed signal that filters out Voice & Video transfers to master chip and separates and handle.

2. audio-video signal treatment circuit according to claim 1 is characterized in that: after handling through an amplifying circuit through the intermediate-freuqncy signal of said tuner output, transfer to described monophone watch circuit again.

3. audio-video signal treatment circuit according to claim 2; It is characterized in that: in said amplifying circuit, include a NPN type triode; The base stage of said triode connects the intermediate-freuqncy signal output of tuner through capacitance; Collector electrode connects DC power supply through current-limiting resistance on the one hand, connects the input of monophone watch circuit on the other hand through another capacitance, and the grounded emitter of said triode is perhaps through another current-limiting resistance ground connection.

4. according to claim 2 or 3 described audio-video signal treatment circuits, it is characterized in that: said amplifying circuit is laid in the position of closing on tuner on the pcb board.

5. audio-video signal treatment circuit according to claim 1; It is characterized in that: after said monophone watch circuit carries out filtration treatment to the intermediate-freuqncy signal that receives; Mixed signal through its two lead-out terminal output difference form transfers to described master chip.

6. audio-video signal treatment circuit according to claim 5 is characterized in that: between two lead-out terminals of said monophone watch circuit, be parallel with an inductance, two lead-out terminals connect described master chip through the capacitance of a series connection separately.

7. according to claim 1 or 5 or 6 described audio-video signal treatment circuits, it is characterized in that: said monophone watch circuit is laid in the position of closing on master chip on the pcb board.

8. audio-video signal treatment circuit according to claim 1; It is characterized in that: in said audio-video signal treatment circuit, also include the voltage stabilizing circuit that is used to change the required operating voltage of generation tuner, said voltage stabilizing circuit is laid in the position of closing on tuner on the pcb board.

9. audio-video signal treatment circuit according to claim 1 is characterized in that: said master chip output intermediate-frequency gain control signal after rc filter circuit is handled, transfers to the intermediate-frequency gain signal input end of said tuner; Said rc filter circuit is laid in the position of closing on tuner on the pcb board.

10. a television set is characterized in that: comprise like the described audio-video signal treatment circuit of each claim in the claim 1 to 9.