CN204046820U - A kind of magneto-resistor audio collection device - Google Patents

Abstract

A kind of magneto-resistor audio collection device, comprise audio collection circuit, audio collection circuit comprises at least one linear reluctance transducer, coupling capacitance, AC amplifier, amplifier and signal processing circuit; Linear reluctance transducer comprises at least one axial linear magneto-resistive sensor unit.Linear reluctance transducer is positioned in the measuring surface on loudspeaker voice coil surface, the signal output part of each axial linear magneto-resistive sensor unit connects AC amplifier with output AC signal respectively by coupling capacitance, then be connected to amplifier and synthesize a signal, and through signal processing circuit output audio signal; Each axial linear magneto-resistive sensor unit is positioned at the linear magnetic field measurement zone in measuring surface.The utility model achieves the collection of loudspeaker audio signal by magnetic Field Coupling between loud speaker and linear reluctance transducer, has the feature of the simple and power saving of structure.

Description

A kind of magneto-resistor audio collection device

Technical field

The utility model relates to magnetic sensor technologies field, particularly a kind of magneto-resistor audio collection device.

Background technology

Audio collection device, namely by being gathered by transducer by the audio-electromagnetically field signal of the loud speaker on smart mobile phone, panel computer or other intelligent electronic devices, and carries out the device play on another loud speaker.

The main audio collection device adopting coil or transformer type at present, by primary coil that the voice coil loudspeaker voice coil of loud speaker transmits as audio electromagnetic field, utilize electromagnetic induction effect to accept in voice coil loudspeaker voice coil as secondary coil audio electro-magnetic signal by receiving coil, its principle is similar to transformer, then by signal processing circuit, in another loud speaker, be again transformed into voice signal.Like this, the audio playing function of wireless connections is realized between loud speaker and audio collection device.This coil type audio collection device, also exists following problem:

1) receiving coil output voltage amplitude is relevant to coil turn and area, therefore needs to increase coil turn and area and could obtain and large accept voltage signal and high sensitivity, therefore cause volume and size larger.

2) signal that loudspeaker voice coil generates an electromagnetic field mainly is centered around area of space near voice coil loudspeaker voice coil, and increases rapid decay with distance, and therefore receiving coil must be positioned at voice coil loudspeaker voice coil near zone as much as possible, causes the flexibility in the space of coil to reduce.

Summary of the invention

The purpose of this utility model is to provide a kind of magneto-resistor audio collection device, amasss the problems such as large to solve existing audio collection body.

For this reason, the utility model provides a kind of magneto-resistor audio collection device, and for the electromagnetic signal of loud speaker is transformed into audio signal, described loud speaker has the measuring surface on voice coil loudspeaker voice coil surface, and described measuring surface has axial service area; Described axial service area is the common factor that linear magnetic field measurement zone in described measuring surface, AC magnetic field measurement zone and snr measurement district are formed, it is characterized in that, comprise audio collection circuit, described audio collection circuit comprises at least one linear reluctance transducer, coupling capacitance, AC amplifier, amplifier and signal processing circuit; Described linear reluctance transducer comprises the axial linear magneto-resistive sensor unit of at least one induction from the signal of described linear magnetic field measurement zone.Each described axial linear magneto-resistive sensor unit all has independent current source input and signal output part, the signal output part of each described axial linear magneto-resistive sensor unit connects described AC amplifier with output AC signal respectively by described coupling capacitance, then be connected to described amplifier and synthesize a signal, and through described signal processing circuit output audio signal.

Also comprise and whether be positioned at linear magnetic field measurement zone control circuit in described measuring surface for detecting each described axial linear magneto-resistive sensor unit, described control circuit be magnetic switch Type Control circuit or direct current output type control circuit or both.

Described magnetic switch Type Control circuit, comprise the magnetic switch sensor with at least one axial magnetic switching sensor cells, comparator and controller, described axial magnetic switching sensor cells and detected axial linear magneto-resistive sensor unit have identical sensitive axes to, for detect described sensitive axes in described measuring surface to magnetic field, the signal output part of described axial magnetic switching sensor cells is connected with described comparator, the reference voltage that signal and the described comparator of the axial linear magneto-resistive sensor unit that described axial magnetic switching sensor cells detects by described comparator store compares, obtain comparison signal, and described comparison signal is input in described controller, so that described controller controls described audio collection circuit according to described comparison signal, described direct current output type control circuit, comprise filter, preposition/differential amplifier, comparator and controller, the signal output part of each described axial linear magneto-resistive sensor unit detected is connected to amplifier by described filter and obtains direct-flow output signal, described direct-flow output signal compares with the reference voltage of described comparator, obtain comparison signal, described comparison signal is input in described controller by described comparator, so that described controller controls described audio collection circuit according to described comparison signal.

Described magnetic switch sensor is the combination of the discrete component of at least two axial magnetic switching sensor cells or the single-chip element of integrated at least two axial magnetic switching sensor cells.

Each described axial magnetic switching sensor cells is X, Y or Z axis magnetic switch sensor.

Each described axial switch sensor unit is the magnetic switch sensor of full pole type.

Described axial linear magneto-resistive sensor unit is half-bridge structure, and the signal output part of described axial linear magneto-resistive sensor unit is connected to preamplifier by filter;

Or;

Described axial linear magneto-resistive sensor unit is full bridge structure, and two signal output parts of described axial linear magneto-resistive sensor unit are connected to differential amplifier respectively by filter

The linear magnetic field bound of each described axial linear magneto-resistive sensor unit and saturation magnetic field are limited to the magnetic manipulation field of each described axial switch sensor unit up and down and reply the reference signal of the value in magnetic field or the comparator of direct voltage Type Control circuit.

Described control circuit also controls detected axial linear magneto-resistive sensor unit respectively for output multi-channel control signal and switches to DC power supply or the pulse power to power and open or disconnect the power supply of described AC amplifier, the power supply of described amplifier, the power supply of described signal processing circuit, any one of magnetic marking signal or several.

Described linear reluctance transducer is the combination of the discrete component of at least two axial linear magneto-resistive sensor unit or the single-chip element of integrated at least two axial linear magneto-resistive sensor unit.

Each described axial linear magneto-resistive sensor unit is X, Y or Z axis transducer.

Described axial linear magneto-resistive sensor unit is half-bridge structure, and the signal output part of described axial linear magneto-resistive sensor unit is connected to preposition AC amplifier by described coupling capacitance;

Or;

Described axial linear magneto-resistive sensor unit is full bridge structure, and two signal output parts of described axial linear magneto-resistive sensor unit are connected to difference AC amplifier respectively by coupling capacitance.

The linear magnetoresistive transducer of at least one single shaft, twin shaft, three axis linear magnetoresistive transducers are positioned at common factor or the union of the axial service area of corresponding each axial linear magneto-resistive sensor unit respectively separately.

Described linear reluctance transducer is the one in AMR, Hall, GMR, TMR transducer.

Described measuring surface is positioned at the scope of distance loudspeaker voice coil surface 0-10mm.

The sensitive axes direction of described axial linear magneto-resistive sensor unit is vertical or parallel to described measuring surface.

Described linear reluctance transducer be positioned at be parallel to described loudspeaker voice coil surface measuring surface on, axial linear magneto-resistive sensor unit described at least one is positioned at the linear magnetic field measurement zone in described measuring surface.

Each described axial linear magneto-resistive sensor unit is positioned at the corresponding axial service area in described measuring surface; In described measuring surface, the linear magnetic field measurement zone in the axial DC magnetic field of described permanent magnetic circuit, non-linear magnetic field measurement zone and saturation magnetic field measurement zone be the linear magnetic field characteristic area of corresponding each described axial linear magneto-resistive sensor unit, non-linear magnetic field characteristic area and saturation magnetic field characteristic area respectively; In described measuring surface, the region that each axial AC magnetic field amplitude that described loudspeaker voice coil produces is greater than 1mG is AC magnetic field measurement zone, and the region being less than 1mG is AC magnetic field non-measured district; In described measuring surface, when frequency band is 15kHz, the signal to noise ratio of each described axial linear magneto-resistive sensor unit output AC audio signal and thermal noise is greater than 1 for snr measurement district, is less than 1 for signal to noise ratio non-measured district.

Described audio collection device is applicable to the loud speaker with circle, track type, rectangular coil.

Described audio collection device is applicable to external magnetic type or internal magnetic loudspeaker.

A kind of magneto-resistor audio collection device that the utility model proposes, utilizes high sensitivity linear reluctance transducer directly voice coil loudspeaker voice coil alternating electromagnetic field signal to be transformed into ac voltage signal and exports, successfully solve above weak point.Because linear reluctance transducer only produces response to its position field signal, and it takes up space, the size of linear reluctance transducer own is only depended in position, and linear reluctance size sensor is much smaller than collection coil dimension, therefore, linear reluctance transducer collector will have larger measurable range, larger space flexibility, and installation dimension needed for it also will reduce greatly, in addition, because linear reluctance transducer has higher magnetic field sensitivity, therefore can obtain than gathering the larger output voltage signal of coil.

Accompanying drawing explanation

Fig. 1 smart mobile phone and smart mobile phone loudspeaker position schematic diagram.

Fig. 2 internal magnetic loudspeaker two-dimensional structure schematic diagram.

Fig. 3 outer-magnet speaker two-dimensional structure schematic diagram.

Fig. 4 loudspeaker voice coil geometry schematic diagram.

Fig. 5 linear reluctance sensor output voltage-external magnetic field indicatrix.

Fig. 6 linear reluctance transducer output resistance-external magnetic field indicatrix.

Fig. 7 internal magnetic loudspeaker D.C. magnetic field two-dimensional magnetic line of force distribution map.

Two-dimentional direct current magnetic distribution figure in Fig. 8 internal magnetic loudspeaker measuring surface.

Fig. 9-11 is respectively D.C. magnetic field Bx, By, Bz measured zone figure in internal magnetization rectangular speaker measuring surface.

Figure 12-14 is respectively D.C. magnetic field Bx, By, Bz measured zone figure in internal magnetization circular loudspeakers measuring surface.

Figure 15 outer-magnet speaker D.C. magnetic field two-dimensional magnetic line of force distribution map.

Two-dimentional direct current Distribution of Magnetic Field figure in Figure 16 outer-magnet speaker measuring surface.

Figure 17-19 is respectively D.C. magnetic field Bx, By, Bz measured zone figure in external magnetic type rectangular speaker measuring surface.

Figure 20-22 is respectively D.C. magnetic field Bx, By, Bz measured zone figure in external magnetic type circular loudspeakers measuring surface.

Figure 23 loudspeaker voice coil two dimension AC magnetism line of force distribution map.

Two-dimentional AC magnetic field distribution map in Figure 24 measuring surface.

Figure 25-27 is respectively AC magnetic field bx in rectangular coil measuring surface, by, bz coordinatograph.

Figure 28-30 is respectively AC magnetic field bx in circular voice coils measuring surface, by, bz coordinatograph.

Figure 31-33 is respectively rectangle internal magnetic loudspeaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction responsive axial magnetic field signal to noise ratio isogram.

Figure 34-36 is respectively circular internal magnetic loudspeaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction responsive axial magnetic field signal to noise ratio isogram.

Figure 37-39 is respectively rectangle outer-magnet speaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction responsive axial magnetic field signal to noise ratio isogram.

Figure 40-42 is respectively circular outer-magnet speaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction responsive axial magnetic field signal to noise ratio isogram.

Figure 43-45 is respectively rectangle outer-magnet speaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction sensitive axes to magnetic-field measurement regional distribution chart.

Figure 46-48 is respectively circular outer-magnet speaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction sensitive axes to magnetic-field measurement regional distribution chart.

Figure 49-51 is respectively rectangle internal magnetic loudspeaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction sensitive axes to magnetic-field measurement regional distribution chart.

Figure 52-54 is respectively circular internal magnetic loudspeaker measuring surface Linear magnetoresistive transducer X, Y, Z-direction sensitive axes to magnetic-field measurement regional distribution chart.

Figure 55-57 is respectively full-bridge, half-bridge, push-pull type full-bridge linear reluctance transducer schematic diagram.

The uniaxially linear reluctance transducer audio collecting system figure of Figure 58 direct current output type control circuit.

The uniaxially linear reluctance transducer audio collecting system figure of Figure 59 magnetic switch Type Control circuit.

Figure 60 magnetic switch sensor external magnetic field-output voltage characteristic curve diagram.

Figure 61-62 is respectively twin shaft, three axis linear magnetoresistive transducer audio collecting system figure.

Figure 63-65 is respectively single shaft, twin shaft, three axis linear magnetoresistive transducer audio collecting system logic control signal tables.

Embodiment

Below with reference to the accompanying drawings and in conjunction with the embodiments, describe the utility model in detail.

Embodiment one

Fig. 1 be intelligent electronic device as loudspeaker position schematic diagram in smart mobile phone, loud speaker 2 is positioned at the screen lower position of smart mobile phone 1.Fig. 2 and Fig. 3 is loadspeaker structure figure, loud speaker comprises permanent magnetic circuit 4 or 4 (1) and voice coil loudspeaker voice coil 3 two parts, permanent magnetic circuit 4 or 4 (1) comprises permanent magnet 5 or 5 (1) and soft magnetic bodies 6 or 6 (1), 7 or 7 (1) and air gap 8 or 8 (1), voice coil loudspeaker voice coil 3 is positioned at air gap 8 or 8 (1) place, because permanent magnetic circuit 4 or 4 (1) produces strong static magnetic field in air gap 8 or 8 (1), when audible communication signal is by voice coil loudspeaker voice coil 3, produce Lorentz force under the static magnetic field effect of voice coil loudspeaker voice coil 3 in air gap 8 or 8 (1) and drive vibrating diaphragm sounding.According to permanent magnet 5 or 5 (1) and soft magnetic bodies 6 or 6 (1) in permanent magnetic circuit 4 or 4 (1), 7 or 7 (1) differences arranged, loud speaker 2 can be divided into internal magnetization and external magnetic type, for the former as Fig. 2, permanent magnet 5 is positioned at the inside of voice coil loudspeaker voice coil 3, for the latter as Fig. 3, permanent magnet 5 (1) is positioned at the periphery of voice coil loudspeaker voice coil 3.Voice coil loudspeaker voice coil 3 has similar geometry with permanent magnetic circuit 4 or 4 (1), and ordinary circumstance is rectangle 12 or circular 11 as shown in Figure 4.Therefore, loud speaker 2 can be divided into external magnetic type circle according to the difference of geometry and permanent magnetic circuit kind, external magnetic type rectangle, 4 kinds of typical structures such as internal magnetization circle and internal magnetization rectangle.

Fig. 2 and Fig. 3 neutral line magnetoresistive transducer 10 be positioned at be parallel to voice coil loudspeaker voice coil 3 and permanent magnetic circuit 4 surface measuring surface 9 on.

Preferably, above-mentioned measuring surface is positioned at the scope of distance loudspeaker voice coil surface 0-10mm.

Embodiment two

Magnetic field due to loud speaker 2 comprises two parts, namely comes from the DC static magnetic field of permanent magnetic circuit 4 or 4 (1) and comes from the AC audio magnetic field of voice coil loudspeaker voice coil 3.Therefore, for the linear reluctance transducer 10 be positioned in measuring surface 9, mean existence bias direct current static magnetic field H, realize with this understanding measuring AC audio magnetic field h, for mobile phone speaker, wherein H amplitude is much larger than h.

Fig. 5,6 resistance versus magnetic field, the output signal voltage-magnetic signature curves being respectively linear reluctance transducer 10, can find out, there are three characteristic areas in linear reluctance transducer 10 in whole magnetic field range, i.e. linear magnetic field characteristic area 13, non-linear magnetic field characteristic area 14 and saturation magnetic field characteristic area 15, only have when DC static magnetic field H is in linear magnetic signature region 13, the voltage signal being transformed into linear reluctance transducer 10 that AC audio field signal h could be correct.Corresponding to measuring surface 9, the DC static magnetic field H on it also can be divided into three magnetic-field measurement regions and linear magnetic field measured zone, non-linear magnetic field measured zone and saturation magnetic field measured zone.

In addition, for linear reluctance transducer 10, also necessarily require AC audio magnetic field h amplitude to be greater than 1mG, could meet and measure requirement, for the existence of less magnetic field due to resolution and noise, measure and will be difficult to realization, now can't output signal.

On this basis, DC static magnetic field H and the Distribution Value of AC audio magnetic field h in three magnetic-field measurement regions in linear reluctance transducer 10 output signal voltages-magnetic signature curve and measuring surface 9 is utilized to determine direct-flow output signal and the audio output signal voltage's distribiuting of linear magnetic field measured zone internal linear magnetoresistive transducer 10 respectively.Further, in order to the distribution of the audio output signal and Johnson thermal noise ratio of determining linear reluctance transducer 10, utilize the spatial distribution of linear reluctance transducer 10 resistance versus magnetic field curve and DC static magnetic field H to determine the distribution of Johnson noise voltage in three magnetic-field measurement regions, and carry out ratio with audio output signal voltage's distribiuting value.

Fig. 7 is the two-dimentional direct current Distribution of Magnetic Field figure of internal magnetic loudspeaker permanent magnetic circuit 4, and can find out, the magnetic line of force has axial symmetry feature, and from permanent magnet 7s, strides across air gap 8, gets back to permanent magnet 7 through soft magnetic bodies 6 and 5.Fig. 8 is that above internal magnetic type magnetic circuit 4, in measuring surface 9, two-dimentional direct current static magnetic field and magnetic field Bx and magnetic field By are along X to distribution map, and as seen from the figure, Bx has antisymmetry distribution characteristics relative to magnetic field, center 0, and By has symmetrical feature relative to center.In addition, from the distribution of the linear magnetic field characteristic area 13 of linear reluctance transducer 10, for Bx, there are three linear magnetic field measurement zones, be namely positioned at 16 regions near magnetic field, center 0, and be positioned at two field decay regions 17 and 18 at two ends.For By, there are 4 linear magnetic field measurement zones, namely be positioned at the region 19 and 20 near two 0 magnetic fields, left and right, and the field decay region 21 and 22 at two ends, field decay region is because magnetic field is away from increasing with distance of occurring during magnet caused by the phenomenon of cube decay.

Fig. 9,10,11 is three-dimensional magnetic field Bx in rectangle internal magnetic loudspeaker measuring surface 9, By, Bz isopleth regional distribution chart, two isopleth wherein indicated represent linear magnetic field characteristic area 13 and non-linear magnetic field characteristic area 14 respectively, and the boundary magnetic field value between non-linear magnetic field feature 14 and saturation magnetic field characteristic area 15, due to the axial symmetry feature of X, Y, only depict the magnetic field distribution of contours figure of 1/4th.Can find out, in measuring surface 9, the saturation magnetic field measurement zone 23 of Bx, the saturation magnetic field measurement zone 26 of non-linear magnetic field measurement zone 24 and saturation magnetic field measurement zone 25 and By, non-linear magnetic field measurement zone 27 and saturation magnetic field measurement zone 28, can find out in conjunction with two-dimensional magnetic field Bx distribution map, three region reality in the district of two-dimensional linear magnetic-field measurement shown in corresponding diagram 8 16,17 and 18 connect into a region 25 or 28 in measuring surface 9.In addition, can find out, in three-dimensional isopleth area distribution Fig. 9, in Bx with Figure 10, By has similar distribution of contours feature, but its phase place have rotated 90 degree relatively.For the Bz in Figure 11, there is two linear magnetic field measured zone, be positioned at voice coil loudspeaker voice coil 3 edge for one 32, be positioned at beyond voice coil loudspeaker voice coil for one 33, its saturation region 29 only accounts for a considerably less part, and is positioned at voice coil loudspeaker voice coil corner, other regions as 30 and 31 be non-linear magnetic field measured zone, the district of two-dimensional linear magnetic-field measurement shown in comparison diagram 8 19 and 20 is linear magnetic-field measurement district 32, and 21 and 22 are 33.

Figure 12, 13, 14 are respectively three-dimensional magnetic field Bx in circular internal magnetic loudspeaker measuring surface 9, By, Bz isopleth regional distribution chart, can find out, Figure 12 and Figure 13 neutral line magnetic-field measurement district 36 and 39 distributing position and rectangle internal magnetic loudspeaker regional distribution chart closely similar, difference is that it is circular arc region, in addition, non-linear magnetic field measurement zone 35 and 38, and saturation magnetic field measurement zone 34 and 37 is also the feature of circular arc, corresponding rectangle internal magnetic loudspeaker distribution of contours Figure 11 is then obviously different from for Bz in Figure 14, there are three linear magnetic field measured zone 44 in it, 43 and 42, corresponding to two-dimensional magnetic field By distribution map 8, can find, the region newly increased is positioned at the low value district, magnetic field of 0 magnetic field near zone, the numerical value in this part magnetic field is relevant to the size of concrete permanent magnetic circuit 4 and the magnetization of permanent magnet 5, it can be positioned at non-linear magnetic field measurement zone or linear magnetic field measurement zone, in rectangle internal magnetic loudspeaker, its value is only reduced to non-linear magnetic field measurement zone, and in circular internal magnetic loudspeaker, its value is then reduced to linear magnetic field measurement zone.Another difference is there is not saturation magnetic field measurement zone in fig. 14.

Embodiment three

Figure 15 is outer-magnet speaker permanent magnetic circuit 4 (1) two-dimensional magnetic line of force distribution map, can find out, the magnetic line of force is from permanent magnet 5 (1) of voice coil loudspeaker voice coil periphery, air gap 8 (1) is striden across through soft magnetic bodies 7 (1), permanent magnet 5 (1) is got back to by soft magnetic bodies 6 (1), equally, its Distribution of Magnetic Field has axial symmetry feature.Figure 16 be in measuring surface 9 two-dimensional magnetic field Bx and By magnetic field X to distribution map, as seen from the figure, Bx still has antisymmetry feature, and By has symmetrical feature, for Bx, because its curve two ends directly stride across 0 point, therefore, it is 46 and 47, except linear magnetic field measurement zone 45 and 48, outside 49 that its linear magnetic field measurement zone adds two relative to internal magnetization permanent magnetic circuit.And for By, then linear magnetic field measurement zone quantity remains unchanged, be 50,51 and 52 and 53.

Figure 17, 18, 19 are respectively three-dimensional magnetic field Bx in measuring surface, By, Bz isopleth regional distribution chart, can find out, different from internal magnetization permanent magnetic circuit, except 55 non-linear magnetic field measurement zones, add a non-linear magnetic field measurement zone 56, and, 55 and 56 peripheral corresponding non-linear magnetic field measurement zones, by two-dimensional magnetic field Bx magnetic field X distribution curve, the region 46 and 47 increased is actually the region between 56 and 55, in graphics, linear magnetic field measurement zone 57 is in fact as a whole, although distribute from two-dimensional magnetic field, linear magnetic field measurement zone increases, but distribute from three-dimensional magnetic field, its actual linear magnetic field measurement zone reduces.

In same Figure 18, By also has similar features, its linear magnetic field measurement zone 61, and saturation magnetic field measurement zone is 58, non-linear magnetic field measurement zone 59 and 60.

For Bz in Figure 19, there is a saturation magnetic field measurement zone 62 in it, be positioned at voice coil loudspeaker voice coil corner, linear magnetic field measured zone is 65 and 66, and the narrow regions wherein in 65 voice coil loudspeaker voice coils, 64 and 63 is non-linear magnetic field measurement zone.

Figure 20,21, the 22 three-dimensional magnetic field Bx being respectively circular outer-magnet speaker permanent magnetic circuit measuring surface 9, By, Bz isopleth regional distribution chart, can find out, except for except arc distribution characteristics, its linear magnetic field measurement zone 70,71, non-linear magnetic field measurement zone 68,69 and 72,73 and saturation magnetic field measurement zone 67 and 71 are very similar to rectangle external magnetic type permanent magnetic circuit.And for Bz in Figure 22, compared with rectangle permanent magnetic circuit, it does not exist saturation magnetic field measurement zone, and its linear magnetic field measurement zone is except 79, outside 78, also add one 77, and its non-linear magnetic field measurement zone is 76 and 75.The characteristics of geomagnetic field distribution of this and circular internal magnetization permanent magnetic circuit measuring surface 9 is closely similar.

Embodiment four

Figure 23 is the two-dimentional AC magnetism line of force distribution map of loudspeaker voice coil 3, and the magnetic line of force, from center, strides across voice coil loudspeaker voice coil edge and gets back to center, forms closed circuit.Figure 24 is the distribution map of two-dimentional AC magnetic field bx in measuring surface 9 and bz.Can find out, bx has antisymmetry distribution characteristics, and bz has symmetrical feature.

For the amplitude range of AC magnetic field, requirement is greater than 1mG, enough signal responses could be produced, as can be seen from Figure 24, for bx, an AC magnetic field non-measured region 80 is there is near magnetic field, central area 0, in addition, also respectively there is an AC magnetic field non-measured region 81 and 82 in field decay region, two ends, and for bz, then near 0 magnetic field, two, two ends, have 83,84 two AC magnetic field non-measured regions, in addition, 85 are also existed equally in field decay region, two ends, 86 two AC magnetic field non-measured regions.Because 1mG numerical value is very little, therefore, can find out, its AC magnetic field non-measured region is very narrow.

Figure 25,26 and 27 is three-dimensional AC magnetic field bx in rectangular coil measuring surface, by, bz distribution of contours figure, can find out, for bx, there are two 1mG isopleth 87 in it, lay respectively near X symmetry axis and field decay district, consistent with two-dimentional AC magnetic field result, therefore its AC magnetic field measurement zone is marginal region.For by, also there is similar result, its 1mG isopleth is 88, for bz, its 1mG isopleth is positioned at narrow zone near the isopleth of diagram 0 magnetic field, and 89 of field decay district, therefore, its AC magnetic field measurement zone is positioned at, between 0 equipotential lines encirclement district, magnetic field and 0 magnetic field and 89 in two regions.Figure 28,29 and 30 are respectively three-dimensional AC magnetic field bx in round voice coil loudspeaker voice coil measuring surface 9, by, bz distribution of contours figure, its 1mG isopleth 90 and 91 lays respectively at 0 magnetic field isopleth near zone, formed one close-shaped, its AC magnetic field measured zone is positioned at closed curve inside, for the bz shown in Figure 30, there is a long and narrow region 92 be positioned near 0 magnetic field, and the 1mG isopleth 93 near decay 0 magnetic field being positioned at excess edge, therefore AC magnetic field measured zone is divided into two parts, lay respectively between 92 and 93, and within 92.

Embodiment five

Figure 31, 32, 33 be corresponding linear reluctance transducer 10 in internal magnetization rectangular speaker measuring surface 9 responsive axial magnetic field respectively along X, Y, during Z-direction, the distribution of contours figure of its AC audio signal and Johnson thermal noise signal ratio, because signal to noise ratio will in the scope being greater than 1, useful signal detection could be realized, and as can be seen from Figure 31 and 32, 94, 95 are respectively X and Y-direction signal to noise ratio is the isopleth of 1, the region wherein surrounded is snr measurement district, in addition, as seen from Figure 33, there are two isopleth is the region of 1, one is positioned at peripheral field decay district 96, it two is positioned near 0 value of 97, correspond to the region between 96 and 97, and the Liang Ge snr measurement district within 97.

Figure 34,35,36 are respectively corresponding internal magnetization circular loudspeakers measuring surface 9 Linear magnetoresistive transducer 10 sensitive axes along X, Y, the signal to noise ratio distribution of contours figure of Z-direction, as can be seen from Figure 34 and 35, signal to noise ratio be 1 isopleth position 102 and 103 be positioned near 0 magnetic field, the region surrounded in it is snr measurement district, and in Figure 36, there is the region that two signal to noise ratios are the isopleth of 1, namely 104 and peripheral 105, therefore, its snr measurement divides into two parts, one between 104 and 105, another is positioned within 104.

Embodiment six

Figure 37,38,39 is that the responsive magnetic field of corresponding external magnetic type rectangular speaker measuring surface 9 Linear magnetoresistive transducer 10 is along X, Y, signal to noise ratio distribution of contours figure during Z-direction, can find out, 106 and 107 are respectively the isogram that numerical value is 1, and its region surrounded is snr measurement district.For Z-direction signal to noise ratio figure, there are two numerical value is the isopleth of 1, and be respectively 108 and 109,108 are positioned at decay area, therefore, within region 109 and 109,108 be Liang Ge snr measurement district.

Figure 40,41,42 are respectively the responsive axial magnetic field of the circular measuring surface 9 Linear magnetoresistive transducer 10 of corresponding external magnetic type along X, Y, signal to noise ratio distribution map during Z-direction, can find out, X, the isopleth 110 that Y-direction signal to noise ratio is 1 and 111 enclosing region are the snr measurement district on corresponding external magnetic type circle detection face 9.For Z-direction, signal to noise ratio be 1 isopleth 112 and 113 form Liang Ge snr measurement district, one is survey regions in 112, and it two is region between 112 and 113, and 113 are positioned at field decay district.

Embodiment seven

Figure 43,44,45 are respectively the responsive axial magnetic field of internal magnetization rectangular speaker measuring surface 9 Linear magnetoresistive transducer 10 respectively along X, Y, its each measurement zone distribution map during Z-direction, wherein 114 is border, linear magnetic field measurement zone, 115 is border, AC magnetic field measurement zone, and 116 is border, snr measurement district, and wherein border, AC magnetic field measurement zone 118 is positioned at border, snr measurement district 119, therefore, X axis service area is arranged in 118 and 117 formation regions.Equally, Y-axis service area is border, linear magnetic field measurement zone 117, in the borderline region that border 118, AC magnetic field measurement zone is formed.For Z-axis direction service area, one is between border, linear magnetic field measurement zone 121 and the border, AC magnetic field measurement zone 124 of decay area, its two between border, linear magnetic field measurement zone 120 and border, AC magnetic field measurement zone 122 region, its three between border, linear magnetic field measurement zone 123 and border, AC magnetic field measurement zone 122 region, 122 regions are very narrow.

Figure 46,47,48 are respectively the responsive axial magnetic field of internal magnetization rectangular speaker measuring surface 9 Linear magnetoresistive transducer 10 respectively along X, Y, its each measurement zone distribution map during Z-direction, similarly, X axis service area is region between border, linear magnetic field measurement zone 125 and border, AC magnetic field measurement zone 126, and border, snr measurement district 127 is positioned at outside 126.Y-axis service area is region between border, linear magnetic field measurement zone 128 and border, AC magnetic field measurement zone 129, and border, snr measurement district 130 is positioned at outside 129.Z-axis direction service area is divided into four parts equally, one is between border, linear magnetic field measurement zone 131 and border, AC magnetic field measurement zone 136, it is two between border, linear magnetic field measurement zone 135 and AC magnetic field measurement zone 132, it is three between 135 and border, linear magnetic field measurement zone 133, and it four is positioned within border, linear magnetic field measurement zone 134.

Figure 49,50,51 are respectively the responsive axial magnetic field of external magnetic type rectangular speaker measuring surface 9 Linear magnetoresistive transducer 10 respectively along X, Y, its each measurement zone distribution map during Z-direction, X axis service area is positioned at region between border, linear magnetic field measurement zone 137,138 and border, AC magnetic field measurement zone 139,140 is border, snr measurement district, is positioned at outside 139.Y-axis service area is positioned at region between border, linear magnetic field measurement zone 141,142 and border, AC magnetic field measurement zone 143, and 144 is border, snr measurement district, is positioned at outside 143.Z-axis direction service area comprises three regions, one is between border, linear magnetic field measurement zone 145 and border, AC magnetic field measurement zone 149, it is two between border, linear magnetic field measurement zone 146 and border, AC magnetic field measurement zone 146, and it is three between border, AC magnetic field measurement zone 146 and linear magnetic field measurement zone 148.

Figure 52,53,54 are respectively the responsive axial magnetic field of external magnetic type circular loudspeakers measuring surface 9 Linear magnetoresistive transducer 10 respectively along X, Y, its each measurement zone distribution map during Z-direction, X axis service area is positioned at region between border, linear magnetic field measurement zone 150,151 and border, AC magnetic field measurement zone 152,153 is border, snr measurement district, is positioned at outside 152.Y-axis service area is positioned at region between border, linear magnetic field measurement zone 154,155 and border, AC magnetic field measurement zone 156, and 157 is border, snr measurement district, is positioned at outside 156.Z-axis direction service area comprises three regions, one is between border, linear magnetic field measurement zone 158 and border, AC magnetic field measurement zone 163, it is two between border, linear magnetic field measurement zone 160 and AC magnetic field measurement zone 161, wherein, border, AC magnetic field measurement zone is positioned at outside measured zone, its three be positioned at border, linear magnetic long measurement zone 162 within.

Embodiment eight

Figure 55,56 and 57 is the structure chart of linear reluctance transducer 10, and be full bridge structure 1101 in Figure 55, comprise four magneto-resistive sensor unit R1, R2, R4 and R5, wherein, R2 and R4 is reference unit, and R1, R5 are sensing unit, and has identical sensitive axes direction.Figure 56 is half-bridge structure 1102, comprises R1, R2 two magnetoresistive cell, and wherein R2 is reference unit, and R1 is sensing unit, and signal is by exporting in the middle of half-bridge.Figure 57 is push-pull type full bridge structure 1103, two magneto-resistive sensor unit R6 adjacent in same brachium pontis, R7 and R8, R9 has contrary magnetic-field-sensitive direction of principal axis, and two the relative magnetoresistive transducer R6 in two brachium pontis, R8 and R7, R9 have the responsive axial direction of opposite magnetic fields.Wherein, magneto-resistive sensor unit can be Hall, AMR, one in GMR or TMR transducer, in addition, the full bridge structure 1101 of linear reluctance transducer 10, half-bridge structure 1102 and push-pull type structure 1103 can be magnetic-field-sensitive direction along the linear reluctance sensor construction of X, Y or Z-direction.

Embodiment nine

The utility model embodiment still provides a kind of magnetic resistance audio collection device, concrete, in audio collection device, control circuit is set, detect with the linear magnetic field measurement zone whether be positioned in described measuring surface each described axial linear magneto-resistive sensor unit, and when detecting that axial linear magneto-resistive sensor unit is in linear magnetic field service area, output multi-channel control signal carries out following partly or entirely operation, as control the axial linear magneto-resistive sensor unit that detects switch to DC power supply, open the power supply of described AC amplifier, open the power supply of described amplifier, open the power supply of described signal processing circuit, open magnetic marking signal, when detecting that axial linear magnetoresistive transducer is not in described linear magnetic field service area, output multi-channel control signal controls following partly or entirely operation respectively, as by the axial linear magneto-resistive sensor unit that detects switch to the pulse power to power, disconnect as described in the power supply of AC amplifier, the power supply disconnecting described amplifier, signal processing circuit as described in disconnection power supply, disconnect described magnetic marking signal.

Figure 58, the 59 Circuits System schematic diagrames being respectively the uniaxially audio collection device of two kinds of different control circuit types and direct current output type and magnetic switch type, it can be the circuit diagram of mono-axial magnetoresistive transducer intelligent audio collector systems, also can be the circuit diagram of each axial linear magnetoresistive transducer in twin shaft or three axis linear magnetoresistive transducer audio collecting systems, wherein twin shaft, three axis linear magnetoresistive transducers are the discrete component combination of multiple axial linear magneto-resistive sensor unit or the single-chip element of integrated multiple axial linear magneto-resistive sensor unit, it is to be noted, for single shaft, twin shaft or three axis linear magnetoresistive transducers, corresponding each axial direction, at least one homoaxial linear reluctance sensor unit can be comprised.

Figure 58 and Figure 59 comprises audio collection circuit and control circuit two parts, and wherein audio collection circuit comprises, unidirectional linearity magneto-resistive sensor unit 1206, coupling capacitance 1207, preposition/difference AC amplifier 1208, preposition/summing amplifier 1209, signal processing circuit 1210.The signal output part of unidirectional linearity magnetoresistive transducer 1206 removes direct-flow output signal through coupling capacitance 1207, what obtain is alternating current output signal, as 1206 is half-bridge structure 1102, then its single-ended signal output and preamplifier 1209 amplify, if 1206 is 1101 full bridge structures or 1103 push-pull type structures, then two signal output parts are connected to two inputs of differential amplifier 1208 respectively by coupling capacitance 1207, the output signal end of preposition/difference AC amplifier 1208 is connected to the input of preposition/summing amplifier 1209, be the linear magnetoresistive transducer audio collecting system of single shaft for unidirectional linearity magnetoresistive transducer 1206, then 1208 inputs being directly connected to preamplifier 1209, if 1206 is a certain axial linear magnetoresistive transducer of twin shaft or three axis linear magnetoresistive transducers, then 1208 inputs being connected to summing amplifier 1209, signal output part output audio signal after signal processing circuit 1210 of preposition/summing amplifier 1209.

Wherein control circuit is divided into two types, and one is the direct current output type shown in Figure 58, and it two is the magnetic switch type shown in 59, and Figure 58 comprises filter 1212, preposition/differential amplifier 1213, comparator 1214 and controller 1204.If 1206 is half-bridge structure 1102, then its single-ended signal output after filtering device 1212 be connected to preamplifier 1213 and obtain direct-flow output signal, and after compare through the reference voltage signal of comparator 1214, reference voltage corresponds to the linear magnetic field characteristic area boundary of 1206, comparator output logic signal 1/0 corresponds to and judges that its unidirectional linearity magnetoresistive transducer 1206 Yes/No detected is within linear magnetic signature region, logical signal is input to controller 1204, controller output signal controls the switching of the DC power supply/pulse power of unidirectional linearity magnetoresistive transducer 1206, and exchange the break-make of preposition/differential amplifier 1208 power supply, the break-make of preposition/summing amplifier 1209 and signal processing circuit 1210 power supply, the on/off of magnetic marking signal.

Figure 59 comprises, single-direction magnetic switch sensor 1304, its sensitive direction is consistent with detected unidirectional linearity magneto-resistive sensor unit 1206, and single-direction magnetic switch sensor is full pole switch, corresponding magnetic field output characteristic curve is as shown in Figure 60, magnetic manipulation field corresponding to it and reply magnetic field are respectively each linear magnetic field to linear reluctance sensor unit and saturation magnetic field limiting value, the output characteristic voltage of magnetic switch sensor is corresponded to through the reference voltage of comparator 1305, thus judge whether the unidirectional linearity magneto-resistive sensor unit 1206 that detects is within axial service area and be transformed into logical signal 1/0, be input in controller 1204, controller output signal controls the switching of the DC power supply/pulse power of unidirectional linearity magneto-resistive sensor unit 1206, and exchange the break-make of preposition/differential amplifier 1208 power supply, the break-make of preposition/summing amplifier 1209 and signal processing circuit 1210 power supply, the on/off of magnetic marking signal.Magnetic switch sensor can be single shaft, twin shaft or three axle magnetic switch sensor, and twin shaft, three axle magnetic switch sensor are the discrete component combination of multiple axial magnetic switching sensor cells or the single-chip element of integrated multiple axial magnetic switching sensor cells; Each axial magnetic switching sensor cells is X, Y or Z axis magnetic switch sensor;

The linear magnetoresistive transducer of single shaft is positioned at respective shaft to the axial service area corresponding to linear reluctance transducer.Twin shaft, three axis linear magnetoresistive transducers are positioned at the common factor of each axial service area corresponding to each axial linear magneto-resistive sensor unit, also can in the union of each axial service area.When being positioned at common factor, multiple axial linear magnetoresistive transducer transmits audio signal simultaneously, therefore output audio signal is each linear reluctance transducer audio signal sum, and time in union, control circuit judges whether each axial linear magnetoresistive transducer is in axial service area, and carry out open-minded to the linear reluctance transducer being in axial service area, measuring surface working range can be expanded like this.

For the ease of simplified characterization two axle, the circuit structure of the audio collecting system of three axis linear magnetoresistive transducers, in Figure 58 and Figure 59, audio collection circuit and control circuit are divided into two structure of block diagram, two block diagrams wherein corresponding to Figure 58 correspond to 1300 and 1350, two block diagrams corresponding to Figure 59 are 1400 and 1350, wherein 1350 is the common ground of two kinds of structures, in addition, corresponding controller and the pulse power/DC power supply with unidirectional linearity magnetoresistive transducer thereof, and exchange preposition/differential signal amplifier power supply, preposition/summing amplifier power supply is also common ground.

The controller logic signal input and output figure of the single shaft linear magnetoresistive transducer audio collection device of Figure 63 corresponding to Figure 58 or 59.Controller input is 1218, output is 1219, 1220, 1221, 1222 and 1223, when 1218 is 0, namely control circuit monitors unidirectional linearity magnetoresistive transducer and is not in linear operating region, now, 1220 is 1, namely be still the pulse power to power, now 1221, 1222, 1223 and 1219 is all 0, exchange preposition/differential amplifier power circuit, preposition/differential amplifier power supply, signal processing circuit power supply all disconnects, otherwise, when 1218 is 1, namely control circuit monitors unidirectional linearity magnetoresistive transducer and is in linear operating region, now, 1220 is 0, namely now DC power supply is switched to, now 1221, 1222, 1223 and 1219 is all 1, now exchange preposition/differential amplifier power circuit, preposition/differential amplifier power supply, signal processing circuit power supply 1708, 1710 is all open-minded, audio signal exports.Single shaft linear magnetoresistive transducer audio collecting system controller input has two kinds of combinations, and output has two, also has two kinds of combinations.

Embodiment ten

By means of the structure of block diagram shown in Figure 58 and 59, Figure 61 is the audio collecting system figure of the linear magnetoresistive transducer of corresponding twin shaft.Except peripheral circuit is as pulse power supply circuit 1200, DC power supply circuit 1201, exchange preposition/differential amplifier power circuit 1202, outside preposition/summing amplifier power circuit 1203 and controller 1204, also comprise block diagram 1350, block diagram 1500 and 1600, three parts, wherein 1500 or 1600 represent that the audio collection circuit of two unidirectional linearity magnetoresistive transducers corresponding to twin shaft linear magnetoresistive transducer and control circuit are according to the structure of block diagram in Figure 58 and Figure 59 respectively, 1500 and 1600 structures can with 1300 or 1400, and exchanging corresponding to 1500 and 1600 preposition/output signal end 1520 of differential amplifier is connected with the summing amplifier 1209 in 1350 with 1521, for two axis linear magnetoresistive transducers, need to use the output signal of summing amplifier 1209 to each axial linear magnetoresistive transducer 1500 and 1600 to sue for peace.In addition, 2 logical signals that control circuit part in 1500 and 1600 produces are input to the input of controller respectively, the control signal that controller exports controls the switching of the DC power supply/pulse power of axial linear magnetoresistive transducer corresponding to 1500 and 1600 respectively, and the interchange of each axial linear magnetoresistive transducer is preposition/break-make of differential amplifier power supply, summing amplifier and signal processing circuit power supply.

The controller input and output logical signal figure of the twin shaft of Figure 64 corresponding to Figure 60 linear magnetoresistive transducer audio collection device.Control circuit input is 1518 and 1519, and control circuit output is 1501,1502,1503,1504,1505,1506,1507 and 1509, and when 1518 and 1519 inputs have 2,4 kinds of combinations, output has 5,4 kinds of combinations.

Embodiment 11

Figure 61 is the audio collecting system figure of corresponding three axis linear magnetoresistive transducers, structure of block diagram corresponding to same employing Figure 58 and 59 characterizes, 1700, 1800 and 1900 characterize each audio collection circuit corresponding to axial linear magnetoresistive transducer and the block diagram of control circuit respectively, 1700, 1800 and 1900 can adopt the one in 1300 or 1400 block diagrams, namely direct current both can have been adopted to export control mode, also magnetic switch control mode can be adopted, 1700, the input of 1800 preposition with the interchange in each the axial linear magnetoresistive transducer audio collection circuit in 1900/differential amplifier is connected the summing amplifier in 1350, and through signal processing circuit output audio signal, and 1700, the input that each 3 logical signals whether being operated in the control circuit of linear zone to linear reluctance transducer are input to controller 1209 is respectively monitored in 1800 and 1900, the output control signal of controller 1209, control 1700 respectively, the switching of each DC power supply/pulse power to linear reluctance transducer in 1800 and 1900, the corresponding power supply exchanging preposition/differential amplifier, the break-make of summing amplifier power supply and signal processing circuit power supply.

The controller logic signal input and output figure of the three axis linear magnetoresistive transducer audio collection devices of Figure 65 corresponding to Figure 61.Controller input is 1811,1812 and 1813, and controller output end is 1701,1702,1703,1704,1705,1706,1707,1708,1709,1710 and 1713.Input has 8 kinds of combinations, and output has 78 kinds combinations.

To sum up, the utility model provides a kind of magneto-resistor audio collection device, and for the electromagnetic signal of loud speaker is transformed into audio signal, described loud speaker has the measuring surface on voice coil loudspeaker voice coil surface, and described measuring surface has axial service area; Described axial service area is the common factor that linear magnetic field measurement zone in described measuring surface, AC magnetic field measurement zone and snr measurement district are formed, it is characterized in that, comprise audio collection circuit, described audio collection circuit comprises at least one linear reluctance transducer, coupling capacitance, AC amplifier, amplifier and signal processing circuit; Described linear reluctance transducer comprises the axial linear magneto-resistive sensor unit of at least one induction from the signal of described linear magnetic field measurement zone.

It should be noted that, when being positioned at the AC magnetic field non-measured district on the linear magnetic field measurement zone in described measuring surface when each described axial linear magneto-resistive sensor unit, measuring less than coherent signal, therefore now can not output signal.

Preferably, each described axial linear magneto-resistive sensor unit all has independent current source input and signal output part, the signal output part of each described axial linear magneto-resistive sensor unit connects described AC amplifier with output AC signal respectively by described coupling capacitance, then be connected to described amplifier and synthesize a signal, and through described signal processing circuit output audio signal.

Preferably, also comprise and whether be positioned at linear magnetic field measurement zone control circuit in described measuring surface for detecting each described axial linear magneto-resistive sensor unit, described control circuit be magnetic switch Type Control circuit or direct current output type control circuit or both.

Preferably, described magnetic switch Type Control circuit, comprise magnetic switch sensor, comparator and the controller with at least one axial magnetic switching sensor cells, described axial magnetic switching sensor cells and detected axial linear magneto-resistive sensor unit have identical sensitive axes to; Described direct current output type control circuit, comprise filter, preposition/differential amplifier, comparator and controller, the signal output part of each described axial linear magneto-resistive sensor unit detected is connected to amplifier by described filter and obtains direct-flow output signal, described direct-flow output signal compares with the reference voltage of described comparator, obtain comparison signal, described comparison signal is input in described controller by described comparator, so that described controller controls described audio collection circuit according to described comparison signal.

Preferably, also comprise output multi-channel control signal to control detected axial linear magneto-resistive sensor unit respectively and switch to DC power supply or the pulse power to power and open or disconnect the power supply of described AC amplifier, the power supply of described amplifier, the power supply of described signal processing circuit, any one of magnetic marking signal or several.

Claims (20)

1. a magneto-resistor audio collection device, for the electromagnetic signal of loud speaker is transformed into audio signal, described loud speaker has the measuring surface on voice coil loudspeaker voice coil surface, and described measuring surface has axial service area; Described axial service area is the common factor that linear magnetic field measurement zone in described measuring surface, AC magnetic field measurement zone and snr measurement district are formed, it is characterized in that, comprise audio collection circuit, described audio collection circuit comprises at least one linear reluctance transducer, coupling capacitance, AC amplifier, amplifier and signal processing circuit; Described linear reluctance transducer comprises the axial linear magneto-resistive sensor unit of at least one induction from the signal of described linear magnetic field measurement zone; Each described axial linear magneto-resistive sensor unit all has independent current source input and signal output part, the signal output part of each described axial linear magneto-resistive sensor unit connects described AC amplifier with output AC signal respectively by described coupling capacitance, then be connected to described amplifier and synthesize a signal, and through described signal processing circuit output audio signal.

2. magneto-resistor audio collection device according to claim 1, it is characterized in that, also comprise and whether be positioned at linear magnetic field measurement zone control circuit in described measuring surface for detecting each described axial linear magneto-resistive sensor unit, described control circuit be magnetic switch Type Control circuit or direct current output type control circuit or both.

3. magneto-resistor audio collection device according to claim 2, it is characterized in that, described magnetic switch Type Control circuit, comprise the magnetic switch sensor with at least one axial magnetic switching sensor cells, comparator and controller, described axial magnetic switching sensor cells and detected axial linear magneto-resistive sensor unit have identical sensitive axes to, for detect described sensitive axes in described measuring surface to magnetic field, the signal output part of described axial magnetic switching sensor cells is connected with described comparator, the reference voltage that signal and the described comparator of the axial linear magneto-resistive sensor unit that described axial magnetic switching sensor cells detects by described comparator store compares, obtain comparison signal, and described comparison signal is input in described controller, so that described controller controls described audio collection circuit according to described comparison signal, described direct current output type control circuit, comprise filter, preposition/differential amplifier, comparator and controller, the signal output part of each described axial linear magneto-resistive sensor unit detected is connected to amplifier by described filter and obtains direct-flow output signal, described direct-flow output signal compares with the reference voltage of described comparator, obtain comparison signal, described comparison signal is input in described controller by described comparator, so that described controller controls described audio collection circuit according to described comparison signal.

4. magneto-resistor audio collection device according to claim 3, is characterized in that, described magnetic switch sensor is the combination of the discrete component of at least two axial magnetic switching sensor cells or the single-chip element of integrated at least two axial magnetic switching sensor cells.

5. magneto-resistor audio collection device according to claim 3, is characterized in that, each described axial magnetic switching sensor cells is X, Y or Z axis magnetic switch sensor.

6. magneto-resistor audio collection device according to claim 3, is characterized in that, each described axial switch sensor unit is the magnetic switch sensor of full pole type.

7. magneto-resistor audio collection device according to claim 3, is characterized in that, described axial linear magneto-resistive sensor unit is half-bridge structure, and the signal output part of described axial linear magneto-resistive sensor unit is connected to preamplifier by filter;

Or;

Described axial linear magneto-resistive sensor unit is full bridge structure, and two signal output parts of described axial linear magneto-resistive sensor unit are connected to differential amplifier respectively by filter.

8. magneto-resistor audio collection device according to claim 2, it is characterized in that, the linear magnetic field bound of each described axial linear magneto-resistive sensor unit and saturation magnetic field are limited to the magnetic manipulation field of each described axial switch sensor unit up and down and reply the reference signal of the value in magnetic field or the comparator of direct voltage Type Control circuit.

9. magneto-resistor audio collection device according to claim 2, it is characterized in that, described control circuit also controls detected axial linear magneto-resistive sensor unit respectively for output multi-channel control signal and switches to DC power supply or the pulse power to power and open or disconnect the power supply of described AC amplifier, the power supply of described amplifier, the power supply of described signal processing circuit, any one of magnetic marking signal or several.

10. magneto-resistor audio collection device according to claim 1, it is characterized in that, described linear reluctance transducer is the combination of the discrete component of at least two axial linear magneto-resistive sensor unit or the single-chip element of integrated at least two axial linear magneto-resistive sensor unit.

11. magneto-resistor audio collection devices according to claim 1, is characterized in that, each described axial linear magneto-resistive sensor unit is X, Y or Z axis transducer.

12. magneto-resistor audio collection devices according to claim 1, it is characterized in that, described axial linear magneto-resistive sensor unit is half-bridge structure, and the signal output part of described axial linear magneto-resistive sensor unit is connected to preposition AC amplifier by described coupling capacitance;

Or;

Described axial linear magneto-resistive sensor unit is full bridge structure, and two signal output parts of described axial linear magneto-resistive sensor unit are connected to difference AC amplifier respectively by coupling capacitance.

13. magneto-resistor audio collection devices according to claim 1, it is characterized in that, the linear magnetoresistive transducer of at least one single shaft, twin shaft, three axis linear magnetoresistive transducers are positioned at common factor or the union of the axial service area of corresponding each axial linear magneto-resistive sensor unit respectively separately.

14. magneto-resistor audio collection devices according to claim 1, is characterized in that, described linear reluctance transducer is the one in AMR, Hall, GMR, TMR transducer.

15. magneto-resistor audio collection devices according to claim 14, is characterized in that, described measuring surface is positioned at the scope of distance loudspeaker voice coil surface 0-10 mm.

16. magneto-resistor audio collection devices according to claim 1, it is characterized in that, the sensitive axes direction of described axial linear magneto-resistive sensor unit is vertical or parallel to described measuring surface.

17. magneto-resistor audio collection devices according to claim 1, described linear reluctance transducer be positioned at be parallel to described loudspeaker voice coil surface measuring surface on, axial linear magneto-resistive sensor unit described at least one is positioned at the linear magnetic field measurement zone in described measuring surface.

18. magneto-resistor audio collection devices according to claim 1, is characterized in that, each described axial linear magneto-resistive sensor unit is positioned at the corresponding axial service area in described measuring surface; In described measuring surface, the linear magnetic field measurement zone in the axial DC magnetic field of permanent magnetic circuit, non-linear magnetic field measurement zone and saturation magnetic field measurement zone be the linear magnetic field characteristic area of corresponding each described axial linear magneto-resistive sensor unit, non-linear magnetic field characteristic area and saturation magnetic field characteristic area respectively; In described measuring surface, the region that each axial AC magnetic field amplitude that described loudspeaker voice coil produces is greater than 1 mG is AC magnetic field measurement zone, and the region being less than 1 mG is AC magnetic field non-measured district; In described measuring surface, when frequency band is 15 kHz, the signal to noise ratio of each described axial linear magneto-resistive sensor unit output AC audio signal and thermal noise is greater than 1 for snr measurement district, is less than 1 for signal to noise ratio non-measured district.

19. magneto-resistor audio collection devices according to claim 1, it is characterized in that, described audio collection device is applicable to the loud speaker with circle, track type, rectangular coil.

20. magneto-resistor audio collection devices according to claim 1, it is characterized in that, described audio collection device is applicable to external magnetic type or internal magnetic loudspeaker.