CN102904002B - Mobile terminal - Google Patents
Mobile terminal Download PDFInfo
- Publication number
- CN102904002B CN102904002B CN201210426941.2A CN201210426941A CN102904002B CN 102904002 B CN102904002 B CN 102904002B CN 201210426941 A CN201210426941 A CN 201210426941A CN 102904002 B CN102904002 B CN 102904002B
- Authority
- CN
- China
- Prior art keywords
- cmmb
- signal
- magnetic bead
- pin
- earphone
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000011324 bead Substances 0.000 claims abstract description 82
- 238000001514 detection method Methods 0.000 claims description 14
- 239000003990 capacitor Substances 0.000 claims description 12
- 230000005236 sound signal Effects 0.000 claims description 11
- 238000013461 design Methods 0.000 abstract description 42
- 238000011161 development Methods 0.000 abstract description 5
- 230000003068 static effect Effects 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000012634 fragment Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 238000012938 design process Methods 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Landscapes
- Headphones And Earphones (AREA)
- Telephone Set Structure (AREA)
Abstract
The invention discloses a mobile terminal, which comprises a host machine, an earphone and a CMMB (China Mobile Multimedia Broadcasting) antenna, wherein an earphone socket for plugging the earphone and the CMMB antenna is arranged on the host machine; the earphone is also used as an FM (Frequency Modulation) antenna; in the earphone socket, a microphone pin or a suspended pin opposite to the microphone pin is connected with a CMMB antenna feed point on a circuit board, and the CMMB antenna feed point is connected with a CMMB chip through a high-pass filter for completely picking off an FM signal and completely breaking over a CMMB signal; the microphone pin is connected with a microphone path through series-connected magnetic beads; and the magnetic beads have a characteristic of picking-off on a CMMB signal working frequency range. The design scheme of a radio frequency antenna sharing the earphone socket adopts the design that two radio frequency paths are separated, so that the problem of mutual influence during debugging antenna match is reduced, the design difficulty of a system is reduced, the circuit structure is simpler, the development cost is reduced, and the development period is shortened.
Description
Technical field
The invention belongs to wireless communication technology field, specifically, relate to a kind of earphone socket structure design of mobile terminal, by earphone socket, realize the compatibility of radio-frequency antenna and peg graft.
Background technology
The DMB CMMB of China Mobile (China Mobile Mutimedia Broadcasting) be domestic independent research and by the first set of SARFT's unified management the system towards multiple mobile terminal, utilize that S-band satellite-signal realizes that " world " one covers, whole nation roaming, support 25 cover TV programme and 30 cover broadcast programs.CMMB is mainly towards the small screen hand held terminal unit, its end product kind mainly comprises that MP4, mobile phone, GPS, USB receive rod, independent receivers etc., digital broadcast television program, integrated information and urgent broadcast service are provided, realize the seamless collaborative covering that satellite transmission combines with ground network.
FM broadcasting FM(Frequency modulate) as a traditional program listening function, be also subject to liking of people always.And along with the intelligent development of mobile phone, it is more and more that multimedia function embodies, the machine of main flow is all compatible CMMB and two kinds of functions of FM.People are also tending towards frivolous gradually to the outward appearance of mobile phone, therefore, how in limited interior of mobile phone space, to realize more function, and this is a huge challenge beyond doubt for the designer of mobile phone.
Tradition compatibility has the mobile terminal of CMMB and two kinds of functions of FM, be generally that FM adopts earphone as antenna, and CMMB adopts built-in telescopic antenna or utilize FPC, PCB or ceramic paster forms CMMB built-in antenna in mobile terminal.Adopt different design defect corresponding to CMMB Antenna Design mode meeting:
(1) adopt built-in pull bar design CMMB antenna, during use, pull bar is pulled out, this design efficiency is low, pull bar needs larger metal empty regions around, and on the mainboard of mobile terminal inside, need to increase feedback point shell fragment, shell fragment needs headroom around, therefore can take the area that mainboard is larger.
(2) adopt FPC, PCB or ceramic paster to form built-in CMMB antenna, this design must take the certain headroom on mainboard, and CMMB antenna can not be placed metal around, unfavorable to the lightening design of current mobile terminal.
(3) adopt special-purpose interface block is set on mobile terminal, mode with grafting cart outside setting antenna designs described CMMB antenna, the interface block that this design is special-purpose because needs increase, therefore can cause the increase of hardware cost and cloth board space.
As can be seen here, in the design process of mobile terminal, for built-in CMMB antenna, at the beginning of product design, just must spatially reserve more region, this lightening development for current mobile terminal is very disadvantageous.
Summary of the invention
The present invention takies in order to solve existing CMMB Antenna Design mode the problem that mobile terminal inner space is large, be unfavorable for the lightening design of mobile terminal, a kind of mobile terminal that utilizes earphone socket grafting CMMB antenna has been proposed, realize the structural design of CMMB antenna and FM antenna duplexer earphone socket, simplified design difficulty.
For solving the problems of the technologies described above, the present invention is achieved by the following technical solutions:
A mobile terminal is provided with the earphone socket for peg graft earphone and CMMB antenna on described mobile terminal; In described earphone socket, CMMB antenna feed point on its microphone pin or the unsettled pin connecting circuit board relative with described microphone pin positions, described CMMB antenna feed point is by ending completely FM signal, the high pass filter of the complete conducting of CMMB signal being connected to CMMB chip, described microphone pin connects microphone path by the first magnetic bead of series connection, and described the first magnetic bead has the characteristic in the cut-off of CMMB signal working frequency range; In described earphone socket, FM antenna feed point on its ground pin, L channel pin or R channel pin connecting circuit board, described FM antenna feed point connects FM chip, described ground pin is by buffer circuit ground connection, and described buffer circuit makes audio signal lead directly to over the ground, make FM signal high resistant over the ground; Described L channel pin connects L channel voice-frequency channel by the second magnetic bead of series connection, and described R channel pin connects right audio channel path by the 3rd magnetic bead of series connection, and described the second magnetic bead and the 3rd magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
Described buffer circuit can adopt various structures design, and the present invention proposes following two kinds of preferred design:
The first, described buffer circuit is comprised of inductance or the 4th magnetic bead having at least in FM signal working frequency range cut-off characteristics, is connected between described ground pin and ground, realizes the effect that audio signal is separated over the ground through to ground, by FM signal;
It two is, described buffer circuit is comprised of electric capacity and inductance in parallel, form resonant selecting frequency network, the resonance frequency of described resonant selecting frequency network be set in the centre frequency of FM signal frequency range, with meet to audio signal over the ground straight-through, to the designing requirement of high resistant over the ground of FM signal.
A kind of preferred circuit teaming method as described high pass filter, described high pass filter is preferably designed to the L-type filter being formed by electric capacity and inductance, described capacitances in series is presented between point and CMMB chip at CMMB, described inductance is connected between CMMB chip and ground, configure the parameter value of described electric capacity and inductance, make cut-off frequency value between the maximum operating frequency of FM signal and the lowest operating frequency of CMMB signal of described high pass filter.
Further, between described CMMB feedback point and ground, be also connected with for realizing the capacitor element of impedance matching.
In order to prevent that static from causing damage to the internal circuit of mobile terminal, need in the microphone path of earphone socket, set up Anti-static device, the capacitive piezo-resistance that preferably adopts in the present invention capacitance to be 0.5PF to the maximum is connected between described microphone pin and ground, to reduce the impact on CMMB signal.
Further, also include headset detection pin in described earphone socket, described headset detection pin connects the master chip on main frame internal circuit board by the 5th magnetic bead, and described the 5th magnetic bead has the characteristic of at least ending at FM signal working frequency range.
In order to facilitate the selection of device, described the first, second, third, fourth, the 5th magnetic bead can be selected the device of same model, all selects the magnetic bead device with the characteristic of ending in 65MHz-860MHz frequency range to meet above-mentioned designing requirement.
As another design of mobile terminal proposed by the invention, on described mobile terminal, be provided with the earphone socket for peg graft earphone and CMMB antenna; In described earphone socket, CMMB antenna feed point on its ground pin connecting circuit board, described CMMB antenna feed point is by ending completely FM signal, the high pass filter of the complete conducting of CMMB signal being connected to CMMB chip, between described CMMB antenna feed point and ground, be connected with the first magnetic bead, described the first magnetic bead has the characteristic in the cut-off of CMMB signal working frequency range; In described earphone socket, FM antenna feed point on its L channel pin or R channel pin connecting circuit board, described FM antenna feed point connects FM chip, described L channel pin connects L channel voice-frequency channel by the second magnetic bead of series connection, described R channel pin connects right audio channel path by the 3rd magnetic bead of series connection, and described the second magnetic bead and the 3rd magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
Preferably, described high pass filter is the L-type filter being formed by electric capacity and inductance, described capacitances in series is between CMMB feedback point and CMMB chip, described inductance is connected between CMMB chip and ground, and the cut-off frequency of described high pass filter is value between the maximum operating frequency of FM signal and the lowest operating frequency of CMMB signal.
Further, in described earphone socket, be also provided with microphone pin and headset detection pin, described headset detection pin connects the master chip on main frame internal circuit board by the 5th magnetic bead, and described microphone pin connects microphone path by the 6th magnetic bead of series connection; Described the 5th magnetic bead and the 6th magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
Preferably, described the first, second, third, the 5th, the 6th magnetic bead all selects the magnetic bead device with the characteristic of ending in 65MHz-860MHz frequency range to carry out the design of circuit system.
Compared with prior art, advantage of the present invention and good effect are: mobile terminal of the present invention can not change in outward appearance and the size of complete machine, inner do not have unnecessary space to design in the situation of built-in CMMB antenna yet, proposed CMMB antenna and FM antenna duplexer earphone socket, and the design that two radio frequency path separates, interactional problem while not only having reduced debugging antenna match, simplified the difficulty of system, and make circuit structure become simpler, reduced development cost, shortened the construction cycle, having solved existing CMMB Antenna Design mode, to take mobile terminal inner space large, the problem that is unfavorable for the lightening design of mobile terminal.
Read by reference to the accompanying drawings after the detailed description of embodiment of the present invention, it is clearer that the other features and advantages of the invention will become.
Accompanying drawing explanation
Fig. 1 is the pin definitions figure of a kind of embodiment of earphone socket in mobile terminal proposed by the invention;
Fig. 2 is the structural representation while inserting four-part form earphone in the earphone socket shown in Fig. 1;
Fig. 3 is the circuit theory diagrams of a kind of embodiment of earphone socket circuit in mobile terminal proposed by the invention;
Fig. 4 is while adopting earphone socket circuit shown in Fig. 3, the circuit theory diagrams of a kind of embodiment of CMMB path;
Fig. 5 is the circuit theory diagrams of another embodiment of earphone socket circuit in mobile terminal proposed by the invention.
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.
FM signal and CMMB signal all belong to radio frequency signal, are operated in different frequency ranges, and wherein, the working frequency range of FM signal is 65MHz～108MHz, and the working frequency range of CMMB signal is 470MHz～860MHz.CMMB signal adopts special antenna to carry out the reception of radiofrequency signal; FM signal is often used common syllogic or four-part form earphone as antenna, receives fm broadcast signal.
In order to simplify the design of two kinds of antennas on mobile terminal, to save taking mobile terminal inner space, facilitate the fabric swatch design of mainboard, the present invention proposes a kind of structural design that realizes CMMB antenna and FM antenna duplexer earphone socket by earphone jack, to solve existing CMMB Antenna Design mode, need to take the inner larger space of mobile terminal, be unfavorable for the problem of the lightening design of mobile terminal.
The receiving sensitivity of considering two kinds of radio frequency signals is an of paramount importance index in mobile terminal design process, if select one of them pin of earphone socket as common feed point, be connected with two radio frequency paths simultaneously, being about to CMMB antenna feed point and FM antenna feed point is connected on the same pin of earphone socket, for example, in the ground pin of earphone socket, when radio frequency reception, between signal, will produce and influence each other, therefore must build a duplexer at rear end use sense container piece, by debugging, accomplish that two paths of signals isolates completely, and the impedance matching that will guarantee two paths of signals meets designing requirement.Obviously, this design circuit structure relative complex, debug difficulties, because two radio frequency paths connect together, thereby is easy to introduce other unknown noise on mainboard, thereby has influence on the overall performance of product.
In order to address this problem, the present invention separates CMMB antenna feed point and FM antenna feed point, the different pins of frames connecting with headphone socket, the different paths of multiplexing head circuit, thereby farthest reduced while using wherein a radio-frequency enabled, to an other harmful effect that radio-frequency enabled causes.
Mobile phone take below as example, by two specific embodiments, elaborate physical circuit assembling structure and the operation principle thereof of CMMB antenna and FM antenna duplexer earphone socket design.
Embodiment mono-, the design of the radio-frequency antenna sharing earphone socket of the present embodiment, select the microphone pin one of earphone socket or the unsettled pin two relative with microphone pin one position to connect the CMMB antenna feed point on circuit board of mobile phone, the FM antenna feed point that the ground pin 4 of selection earphone socket connects on circuit board of mobile phone, shown in Figure 1, the mobile phone circuit designing thus, by the microphone path of CMMB path and interior of mobile phone is multiplexing, FM path and earphone ground path is multiplexing, thereby can avoid well influencing each other between two-way radiofrequency signal, reduce the debugging difficulty of radio-frequency performance.
In the present embodiment, described earphone socket can select six common pin formula earphone sockets to be arranged on the main frame of mobile phone, specifically comprise microphone pin one, unsettled pin two, R channel pin 3, ground pin 4, L channel pin 5 and headset detection pin 6, as shown in Figure 1.Wherein, microphone pin one is relative with the position of unsettled pin two, while inserting four-part form earphone in earphone jack, all contacts connection with the second segment of headset plug, and described headset plug is defined as four sections of first paragraphs to the successively from inner side to outside, shown in Fig. 2; R channel pin 3 is relative with the position of ground pin 4, and while inserting four-part form earphone in earphone jack, the 3rd section of R channel pin 3 and headset plug contacts, and ground pin 4 contacts with the first paragraph of headset plug by metal clips; L channel pin 5 is relative with the position of headset detection pin 6, while inserting four-part form earphone in earphone jack, all contacts connection with the 4th section of headset plug.
Earphone path with the corresponding connection of each pin in described earphone socket is set on the mainboard of mobile phone, to meet the transmission requirement of earphone signal, realizes ear-phone function.In order to realize mobile phone, receive the function of mobile television signal and broadcast listening, on cell phone mainboard, be provided with CMMB chip and FM chip simultaneously, respectively with the corresponding connection of CMMB antenna feed point and FM antenna feed point, to meet transmitting-receiving and the processing requirements to CMMB signal and FM signal.Meanwhile, for CMMB antenna and FM antenna can be shared with earphone socket, described CMMB antenna feed point is connected on the microphone pin one or unsettled pin two of earphone socket (the present embodiment is following take connect unsettled pin two describe as example), FM antenna feed point is connected in the ground pin 4 of earphone socket, and by the circuit structure of earphone path is improved, to meet the normal transmission requirement of three road signals (earphone signal, CMMB signal, FM signal).
For fear of earphone signal, CMMB signal and FM signal, produce each other interference effect in transmitting procedure, the present embodiment adopts following design to being connected to the circuit of described earphone socket periphery, shown in Fig. 3:
(1) when user need to use CMMB function, CMMB antenna is inserted in earphone jack, CMMB antenna feed point links together by the microphone pin one of CMMB antenna and earphone socket U1.Because the microphone path of CMMB antenna feed point and earphone is multiplexing, therefore must consider the impact of microphone path on CMMB signal, the satisfactory magnetic bead of can connecting in microphone path.Magnetic bead is equivalent to band stop filter at full frequency band, the magnetic bead of different model, and the centre frequency of its cut-off is different with bandwidth.In the present embodiment, the first magnetic bead L1301 that selection has in the working frequency range cut-off characteristics of CMMB signal is connected in microphone path, be cut-off frequency at 470MHz ~ 860MHz or comprise the larger bandwidth of this frequency range, to reduce the impact of microphone path signal on CMMB signal.
Simultaneously, when preventing that CMMB antenna is in being inserted into earphone jack, static is incorporated in mobile phone circuit, CMMB chip is caused damage, the present embodiment is used Anti-static device in microphone path, such as selecting that the piezo-resistance RV1302 of the little low electric capacity of CMMB effect of signals is connected between microphone pin one and ground, to realize static releasing fast over the ground.The capacitance of described piezo-resistance RV1302 is preferably 0.5PF or following, but for the ESD device with detecting action, can not in the microphone path of the present embodiment, use, because there is the ESD device of detecting action, can produce serious influence to CMMB signal.
In addition, when putting device, described the first magnetic bead L1301 and piezo-resistance RV1302 should lay near earphone socket U1, to avoid because the first magnetic bead L1301 is long to the cabling of earphone socket, or piezo-resistance RV1302 is long to the cabling of earphone socket, and CMMB signal is exerted an influence.
In addition, consider the impact of CMMB path on microphone signal, because the voltage drawing on having on microphone path, thus on CMMB path, need to have electric capacity every directly, and can not use inductance or magnetic bead ground connection between electric capacity and earphone socket U1.
(2) when the described CMMB path of design, consider when in being inserted into earphone jack, earphone is three-section earphone, because the microphone pin one of earphone socket, unsettled pin two and ground pin 4 all contact connection with same section of headset plug, thereby CMMB antenna feed point, microphone path and FM antenna feed point are connected together by headset plug.Due to for FM antenna, can adopt common headphones to double as the antenna into FM, thereby for fear of FM signal error be incorporated into CMMB chip, the present embodiment has designed high pass filter between CMMB antenna feed point and CMMB antenna, as shown in Figure 4.Described high pass filter have to FM signal end completely, characteristic to the complete conducting of CMMB signal, preferably adopt a capacitor C 2 and inductance L 1(or magnetic bead) form the high pass filter of L-type.Capacitor C 2 is connected between CMMB feedback point and CMMB chip, plays the effect that the direct current signal in microphone path is isolated simultaneously; By inductance L 1(or magnetic bead) be connected between CMMB chip and ground, by adjusting capacitor C 2 and inductance L 1(or magnetic bead) parameter value, thereby the cut-off frequency that makes high pass filter can drop between the maximum operating frequency of FM signal and the lowest operating frequency of CMMB signal, i.e. value between 108MHz to 460MHz, with assurance, FM signal is ended completely, to the complete conducting of CMMB signal.So both can reduce the loss of FM signal on CMMB path, can prevent again that the static of earphone socket end from causing damage to CMMB chip.
When CMMB end debugging impedance matching, the capacitor element C1 of a low-capacitance can be connected between CMMB feedback point and ground, as shown in Figure 4.Described capacitor C 1 should be selected several PF or tens other little electric capacity of PF level, to reduce the impact on FM signal.
(3) consider that FM feedback point is connected with the ground pin of earphone socket U1, and the ground pin of earphone socket U1 is also the earth terminal of earphone left and right acoustic channels and microphone path simultaneously, because the frequency of voice signal is generally between 20Hz～20KHz, with respect to FM signal, be equivalent to direct current, therefore when circuit design, must between FM feedback point and ground, connect buffer circuit, shown in Figure 3.The audio signal of making that has described buffer circuit leads directly to, makes the FM signal characteristic of high resistant over the ground over the ground, can realize thus when transmitting earphone signal by earphone, the audio signal of low frequency can, by described buffer circuit through to ground, can normally be used earphone; And when utilizing earphone as FM antenna, can make the FM signal of 65MHz～108MHz frequency range separate over the ground, and be successfully passed in FM chip, realize the function that mobile phone is answered FM broadcasting.
In the present embodiment, described buffer circuit can adopt inductance or a 4th magnetic bead L1305 who has at least in the working frequency range cut-off characteristics of FM signal to be connected between described FM antenna feed point and ground, as shown in Figure 3.Because described inductance or the 4th magnetic bead L1305 are equivalent to lead directly to for the audio signal of low-frequency range, thereby can guarantee the normal ground connection of earth terminal of earphone left and right acoustic channels and microphone path, meet the instructions for use of earphone; But for FM signal, because described inductance or the 4th magnetic bead L1305 are high-impedance state in 65MHz～108MHz frequency range, thereby can avoid FM signal to be transferred to ground, guarantee that FM signal is to FM chip normal transmission.
Certainly, described buffer circuit also can adopt a capacitor C 1304 and an inductance L 1305 to compose in parallel, and is connected between FM antenna feed point and ground, forms resonant selecting frequency network, as shown in Figure 3.Configure the parameter value of described capacitor C 1304 and inductance L 1305, make the resonance frequency of the resonant selecting frequency network that forms just in the centre frequency of FM signal frequency range, can meet equally the designing requirement of buffer circuit.
(4) between the audio signal of earphone left and right sound channels and FM signal, exert an influence, the present embodiment magnetic bead of connecting respectively in the left and right acoustic channels voice-frequency channel of earphone, utilize this magnetic bead at the working frequency range of FM signal, to there is the characteristic of cut-off, the impact of avoiding audio signal to produce FM path.Specifically, the L channel pin 5 of earphone socket U1 can be connected to L channel voice-frequency channel by the second magnetic bead L1306 connecting, R channel pin 3 is connected to right audio channel path by the 3rd magnetic bead L1307 connecting, and described the second magnetic bead L1306 and the 3rd magnetic bead L1307 should at least have the characteristic in the cut-off of 65MHz～108MHz frequency range.
In order to prevent electrostatic damage, can also be further between the L channel pin 5 of described earphone socket U1 and ground and between R channel pin 3 and ground, be connected respectively piezo-resistance RV1304, a RV1307, as shown in Figure 3.
(5) for the detection pin 6 of earphone socket U1, the 5th magnetic bead L1303 by series connection connects the master chip on cell phone mainboard on the one hand, described the 5th magnetic bead L1303 has the characteristic in the cut-off of FM signal working frequency range, to realize mobile phone master chip, earphone is inserted to the accurate detection of state; On the other hand by piezo-resistance RV1301 ground connection, to prevent static damage.
Consider the convenience problem of circuit design and magnetic bead parts selection, the present embodiment preferably adopts the magnetic bead device of same model to carry out the circuit design shown in Fig. 3, preferably adopt cut-off frequency range at the magnetic bead device of 65MHz-860MHz as the first to the 5th described magnetic bead, meet the insulation request of each path of earphone to FM signal and CMMB signal, to reduce the loss to FM signal and CMMB signal.
Certainly, also FM antenna feed point can be connected on the L channel pin 5 or R channel pin 3 of earphone socket U1, CMMB antenna feed point is connected on the microphone pin one or the unsettled pin two relative with microphone pin positions of earphone socket U1, and adopt the earphone socket circuit design shown in Fig. 3, can meet equally the designing requirement of FM antenna and CMMB antenna duplexer earphone socket.
Embodiment bis-, and the design of the FM antenna of the present embodiment and CMMB antenna duplexer earphone socket selects the L channel pin 5 of earphone socket U1 or R channel pin 3 to connect FM antenna feed point, selects the ground pin 4 of earphone socket U1 to connect CMMB antenna feed point.By the left and right acoustic channels path of FM path and earphone is multiplexing, the grounded circuit of CMMB path and earphone is multiplexing, can avoid well influencing each other between two-way radiofrequency signal equally, reduce the debugging difficulty of radio-frequency performance.
When adopt the present embodiment to propose path reuse plan mode time, in order to meet the normal transmission requirement of earphone signal, FM signal and CMMB signal, the present embodiment first by CMMB antenna feed point by FM signal is ended completely, the high pass filter of the complete conducting of CMMB signal is connected to CMMB chip, when guaranteeing that CMMB signal can transfer to CMMB chip smoothly, can also avoid FM signal to produce loss on CMMB path.Secondly, between described CMMB antenna feed point and ground, be connected magnetic bead or an inductance having in the working frequency range cut-off of CMMB signal, the first magnetic bead L1301 for example, shown in Figure 5, so that the ground pin of earphone socket U1 4 and ground are separated, thereby when avoiding CMMB signal to be transferred to ground, can also make the audio signal of low frequency straight-through over the ground, meet the instructions for use of earphone.Then, FM antenna feed point is connected to FM chip, and the magnetic bead of connecting respectively in left and right sound channels path, headset detection path and the microphone path of earphone, the attenuation loss impact of CMMB signal and FM signal and CMMB path being produced FM signal by earphone to reduce noise in mainboard.
Specifically, can be by the L channel pin of earphone socket U1 5 by the second magnetic bead L1306 connection L channel voice-frequency channel of series connection; R channel pin 3 is connected to right audio channel path by the 3rd magnetic bead L1307 connecting; Microphone pin one is connected to microphone path by the 6th magnetic bead L1308 connecting; Headset detection pin 6 is connected to the master chip on cell phone mainboard by the 5th magnetic bead L1303 connecting.Described the first, second, third, the 5th, the 6th magnetic bead should be selected the magnetic bead having at least in FM signal working frequency range cut-off characteristics, to reduce the impact on CMMB signal and FM signal.
Same, for to simplifying circuit design, facilitate the consideration of parts selection aspect, described the first, second, third, the 5th, the 6th magnetic bead can all select the magnetic bead device with the characteristic of ending in 65MHz-860MHz frequency range to carry out the design of circuit system, to meet for transmitting each path of earphone signal, audio signal can be normally by and designing requirement that FM signal and CMMB signal are blocked.
For described high pass filter, can adopt equally L-type filter circuit assembling structure as shown in Figure 4, the capacitor C 2 that is about to low-capacitance is connected between CMMB antenna feed point and CMMB chip, inductance or magnetic bead L1 are connected between CMMB chip and ground, to avoid FM signal to produce decay on CMMB path.
In order to prevent that the static of earphone socket end from causing damage to CMMB chip, can and detect at the microphone pin one of earphone socket U1, R channel pin 3, L channel pin 5 the ESD device that is connected respectively a piezo-resistance between pin 6 and ground or there is detecting action, as the RV1301 in Fig. 5, RV1302, RV1304, RV1307, to realize electrostatic induced current releasing fast over the ground.
It should be noted that the left and right sound channels pin that CMMB antenna feed point can not frames connecting with headphone socket U1, because these two pins, near mainboard inner side, insert after antenna, with shell fragment around, can produce parasitic capacitance, to the decay of signal with disturb all larger.
In addition, in left and right sound channels voice-frequency channel, RC filter circuit can also be further set, the filter circuit being for example comprised of resistance R 1303 and capacitor C 1307 and the filter circuit being comprised of resistance R 1307 and capacitor C 1312, for filtering high-frequency interferencing signal, guarantee tonequality.
Certainly; the above is only a kind of preferred implementation of the present invention, for those skilled in the art, and under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (10)
1. a mobile terminal, is characterized in that: on described mobile terminal, be provided with the earphone socket for peg graft earphone and CMMB antenna; In described earphone socket, CMMB antenna feed point on its microphone pin or the unsettled pin connecting circuit board relative with described microphone pin positions, described CMMB antenna feed point is by ending completely FM signal, the high pass filter of the complete conducting of CMMB signal being connected to CMMB chip, described microphone pin connects microphone path by the first magnetic bead of series connection, and described the first magnetic bead has the characteristic in the cut-off of CMMB signal working frequency range; In described earphone socket, FM antenna feed point on its ground pin, L channel pin or R channel pin connecting circuit board, described FM antenna feed point connects FM chip, described ground pin is by buffer circuit ground connection, and described buffer circuit makes audio signal lead directly to over the ground, make FM signal high resistant over the ground; Described L channel pin connects L channel voice-frequency channel by the second magnetic bead of series connection, and described R channel pin connects right audio channel path by the 3rd magnetic bead of series connection, and described the second magnetic bead and the 3rd magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
2. mobile terminal according to claim 1, is characterized in that: described buffer circuit is comprised of inductance or the 4th magnetic bead having at least in FM signal working frequency range cut-off characteristics; Or described buffer circuit is comprised of electric capacity and inductance in parallel, form resonant selecting frequency network, the resonance frequency of described resonant selecting frequency network is in the centre frequency of FM signal frequency range.
3. mobile terminal according to claim 1, it is characterized in that: the L-type filter of described high pass filter for being formed by electric capacity and inductance, described capacitances in series is between CMMB feedback point and CMMB chip, described inductance is connected between CMMB chip and ground, and the cut-off frequency of described high pass filter is value between the maximum operating frequency of FM signal and the lowest operating frequency of CMMB signal.
4. mobile terminal according to claim 3, is characterized in that: between described CMMB feedback point and ground, be connected with the capacitor element for impedance matching.
5. mobile terminal according to claim 1, is characterized in that: described microphone pin is the capacitive piezo-resistance ground connection of 0.5PF to the maximum by capacitance.
6. according to the mobile terminal described in any one in claim 2 to 5, it is characterized in that: in described earphone socket, also include headset detection pin, described headset detection pin connects the master chip on main frame internal circuit board by the 5th magnetic bead, and described the 5th magnetic bead has the characteristic of at least ending at FM signal working frequency range.
7. mobile terminal according to claim 6, is characterized in that: described the first, second, third, fourth, the 5th magnetic bead has the characteristic in the cut-off of 65MHz-860MHz frequency range.
8. a mobile terminal, is characterized in that: on described mobile terminal, be provided with the earphone socket for peg graft earphone and CMMB antenna; In described earphone socket, CMMB antenna feed point on its ground pin connecting circuit board, described CMMB antenna feed point is by ending completely FM signal, the high pass filter of the complete conducting of CMMB signal being connected to CMMB chip, between described CMMB antenna feed point and ground, be connected with the first magnetic bead, described the first magnetic bead has the characteristic in the cut-off of CMMB signal working frequency range; In described earphone socket, FM antenna feed point on its L channel pin or R channel pin connecting circuit board, described FM antenna feed point connects FM chip, described L channel pin connects L channel voice-frequency channel by the second magnetic bead of series connection, described R channel pin connects right audio channel path by the 3rd magnetic bead of series connection, and described the second magnetic bead and the 3rd magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
9. mobile terminal according to claim 8, it is characterized in that: the L-type filter of described high pass filter for being formed by electric capacity and inductance, described capacitances in series is between CMMB feedback point and CMMB chip, described inductance is connected between CMMB chip and ground, and the cut-off frequency of described high pass filter is value between the maximum operating frequency of FM signal and the lowest operating frequency of CMMB signal.
10. mobile terminal according to claim 8 or claim 9, it is characterized in that: in described earphone socket, be also provided with microphone pin and headset detection pin, described headset detection pin connects the master chip on main frame internal circuit board by the 5th magnetic bead, and described microphone pin connects microphone path by the 6th magnetic bead of series connection; Described the 5th magnetic bead and the 6th magnetic bead have the characteristic in the cut-off of FM signal working frequency range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210426941.2A CN102904002B (en) | 2012-10-31 | 2012-10-31 | Mobile terminal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210426941.2A CN102904002B (en) | 2012-10-31 | 2012-10-31 | Mobile terminal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102904002A CN102904002A (en) | 2013-01-30 |
| CN102904002B true CN102904002B (en) | 2014-12-03 |
Family
ID=47576137
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210426941.2A Expired - Fee Related CN102904002B (en) | 2012-10-31 | 2012-10-31 | Mobile terminal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102904002B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104253308A (en) * | 2013-06-28 | 2014-12-31 | 深圳富泰宏精密工业有限公司 | Antenna and wireless communication device |
| CN103414042A (en) * | 2013-07-25 | 2013-11-27 | 苏州三星电子电脑有限公司 | Four-segment type headphone port and laptop with same |
| CN104469615A (en) * | 2014-12-15 | 2015-03-25 | 上海华勤通讯技术有限公司 | Terminal device and earphone circuit thereof |
| WO2018058685A1 (en) * | 2016-09-30 | 2018-04-05 | 深圳达闼科技控股有限公司 | Earphone socket, radio-frequency signal plug, communication terminal, matching structure, and device |
| CN106921901B (en) * | 2017-02-22 | 2019-07-09 | Oppo广东移动通信有限公司 | Mobile terminal and earphone socket |
| CN107426361B (en) * | 2017-06-15 | 2023-09-12 | 上海集赫电子商务有限公司 | 4G small-screen mobile phone motherboard and 4G small-screen mobile phone |
| CN109256615B (en) * | 2017-07-14 | 2022-11-01 | 中兴通讯股份有限公司 | Antenna performance adjusting method and device and readable storage medium |
| CN107528937B (en) * | 2017-07-24 | 2020-05-19 | 捷开通讯(深圳)有限公司 | Mobile communication equipment and antenna thereof |
| CN107728991B (en) * | 2017-09-30 | 2021-01-15 | 联想(北京)有限公司 | Electronic equipment and FM playing method |
| CN108289266B (en) * | 2018-01-11 | 2021-04-27 | 上海展扬通信技术有限公司 | Noise reduction circuit and mobile terminal |
| CN113810816B (en) * | 2021-09-17 | 2024-01-23 | 维沃移动通信有限公司 | Earphone, frequency modulation signal receiving system and method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102427192A (en) * | 2011-08-05 | 2012-04-25 | 中兴通讯股份有限公司 | Connector, earphone antenna and earphone |
| CN102610914A (en) * | 2012-03-30 | 2012-07-25 | 上海华勤通讯技术有限公司 | China Mobile Multimedia Broadcasting (CMMB) antenna |
| CN202424711U (en) * | 2011-12-21 | 2012-09-05 | 比亚迪股份有限公司 | CMMB (China mobile multimedia broadcasting) antenna system and mobile terminal applying same |
-
2012
- 2012-10-31 CN CN201210426941.2A patent/CN102904002B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102427192A (en) * | 2011-08-05 | 2012-04-25 | 中兴通讯股份有限公司 | Connector, earphone antenna and earphone |
| CN202424711U (en) * | 2011-12-21 | 2012-09-05 | 比亚迪股份有限公司 | CMMB (China mobile multimedia broadcasting) antenna system and mobile terminal applying same |
| CN102610914A (en) * | 2012-03-30 | 2012-07-25 | 上海华勤通讯技术有限公司 | China Mobile Multimedia Broadcasting (CMMB) antenna |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102904002A (en) | 2013-01-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102904002B (en) | Mobile terminal | |
| US7840242B2 (en) | Earphone antenna | |
| CN101316111B (en) | Mobile terminal headphone | |
| CN103297887B (en) | Earphone, the circuit structure of mobile device and mobile device | |
| WO2021120382A1 (en) | Antenna assembly and mobile terminal | |
| CN112653488A (en) | Radio frequency module, antenna control method and electronic equipment | |
| CN203398293U (en) | External antenna, wireless device and wireless equipment | |
| TW201742314A (en) | Receiver and RF signal supply device | |
| US7559803B2 (en) | Connection structure and signal transmission cable | |
| CN104409850B (en) | The structure of antenna is used as by the use of terminal receiver | |
| TW201246811A (en) | I/o device | |
| CN102290693B (en) | Connecting device, earphone antenna and earphone | |
| CN102821173A (en) | Antenna system of mobile phone | |
| WO2014023238A1 (en) | Cmmb antenna device sharing fm function of terminal earphone and terminal | |
| US9681214B2 (en) | Integrated earbud antenna for receiving television broadcasts | |
| KR20110019841A (en) | Method and apparatus for improving audio channel cross talk in portable terminal | |
| CN101951268A (en) | Method and device for improving performance of radio antenna | |
| WO2012151844A1 (en) | Connection device, headphone antenna, and headphone | |
| KR100783406B1 (en) | Broadcasting receiving apparatus, broadcasting receiving antenna and broadcasting receiving method | |
| CN202713580U (en) | Earphone compatible interface circuit for terminal device | |
| CN202425018U (en) | Earphone terminal interface circuit and set top box with the same | |
| CN102725907B (en) | CMMB antenna, CMMB earphone antenna and mobile terminal | |
| CN101026385A (en) | Mobile communication devices | |
| US10045118B2 (en) | Integrated antenna for receiving television broadcasts | |
| CN201781064U (en) | Device for improving performance of radio antenna |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141203 |