CN202026459U - Radio frequency interference-free capacitance microphone apparatus - Google Patents
Radio frequency interference-free capacitance microphone apparatus Download PDFInfo
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- CN202026459U CN202026459U CN2010206700194U CN201020670019U CN202026459U CN 202026459 U CN202026459 U CN 202026459U CN 2010206700194 U CN2010206700194 U CN 2010206700194U CN 201020670019 U CN201020670019 U CN 201020670019U CN 202026459 U CN202026459 U CN 202026459U
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Abstract
The utility model discloses a radio frequency interference-free capacitance microphone apparatus, comprising an electrode, a field effect transistor, a capacitor in parallel connection, a filtering resistor, and an RC circuit, wherein one end of the electrode is connected to an output end, with the other end being connected to the grounding end; the field effect transistor comprises a gate electrode, a source electrode, and a drain, with the gate electrode being connected with the electrode, the source electrode being connected with the grounding end, and the drain being connected with the output end; the capacitor in parallel connection is arranged between the output end and the grounding end and is respectively connected to both ends of the electrode; the filtering resistor is arranged between the gate electrode of the field effect transistor and the electrode, filtering the noise entering the capacitance microphone apparatus; and the RC circuit is arranged across the output end and the grounding end, preventing high-frequency signals from entering the capacitance microphone apparatus. The field effect transistor of the radio frequency interference-free capacitance microphone apparatus disclosed in the utility model can be equipped with a diode for electrostatic protection to ensure the performance of the components will not be damaged by the static.
Description
[technical field]
The utility model belongs to the Electret Condencer Microphone technical field, particularly a kind of capacitive microphone device that utilizes RC circuit (phase-shift circuit) as the anti-radio frequency interference of filtering high-frequency noise.
[background technology]
Flourish along with the 3C electronic product, Electret Condencer Microphone requires relatively more and more higher for the conversion performance of sound, particularly work as capacitive microphone device on communication product, can produce radiofrequency signal for fear of communication product, and make Electret Condencer Microphone easily produce noise, in order to solve such problem, the general mode that solves is generally provides an electric capacity in parallel with as filter between the drain of knot face type field-effect transistor (JFET) and source electrode, in order to the shielded radio frequency signal to reduce noise.
Afterwards, there is the dealer to develop existing capacitive microphone device as shown in Figure 1, comprise and a pair ofly shake by sound and cause the electrode EL of change in voltage, the two ends of electrode EL connect the A contact of positively charged pressure and the B contact of an electronegative pressure respectively, one is used to cushion the knot face type field-effect transistor JFET of voltage on the magnifying electrode EL two ends, knot face type field-effect transistor JFET comprises the gate G of connection electrode EL, the drain D and the source S that is connected the B contact that connect the A contact, two shunt capacitance C1, a C2 end respectively is connected to the A contact, the other end is connected to the B contact, and one inductance L be arranged between A contact and the drain D, big by the impedance of inductance L when the high frequency, and then the decay radio frequency interference, increase filter effect.
Yet aforementioned capacitive microphone device, there is no the function of electrostatic defending, therefore can't avoid product to be subjected to deterioration and damage that static causes, moreover, also can't filter non-essential signal enters microphone to inductance L that Electret Condencer Microphone utilizes, and makes that its filter effect is not preferable, and the while is for fear of the cost height of single inductance L, make that integral capacitor formula microphone price is difficult for accepting extensively for industry, therefore the space of improvement is still arranged.
[utility model content]
Because above-mentioned problem, the purpose of this utility model is to provide a kind of capacitive microphone device of the RC of having circuit, and it utilizes the setting of RC circuit, to intercept in the high-frequency noise access to plant, and then reach the purpose of anti-radio frequency interference, solve the defective that prior art exists.
For achieving the above object, the capacitive microphone device of a kind of anti-radio frequency interference described in the utility model, it includes an electrode, a field-effect transistor, an electric capacity in parallel, a filtration resistance and a RC circuit.Electrode one end is connected in an output, the other end is connected in an earth terminal, field-effect transistor has a gate, one source pole and a drain, gate is connected with electrode, source electrode is connected in earth terminal, drain is connected in output, shunt capacitance is arranged between output and the earth terminal, and be connected to the two ends of electrode, filtering resistance is arranged between the gate and electrode of field-effect transistor, filtered noise enters in the capacitive microphone device, and the RC circuit is crossed between output and the earth terminal, intercepts high-frequency signals and enters in this capacitive microphone device.
The capacitive microphone device of anti-radio frequency interference described in the utility model can with shunt capacitance and to filter resistance integrated with field-effect transistor, makes condenser type gram wind apparatus minimizing Layout space, reaches the purpose of the miniaturization of products.
In addition, the capacitive microphone device of anti-radio frequency interference described in the utility model, its field-effect transistor is other can be provided with diode, as electrostatic defending, is unlikely to be subjected to static and to damage with the performance of guaranteeing spare part.
[description of drawings]
Fig. 1 is a capacitive microphone device electrical block diagram of the prior art.
Fig. 2 is the circuit diagram of the capacitive microphone device of embodiment 1 described anti-radio frequency interference.
Fig. 3 is the schematic diagram of an integrated circuit for Fig. 2 is partly circuit integrated.
Fig. 4 is the capacitive microphone device circuit diagram of embodiment 2 described anti-radio frequency interference.
Fig. 5 is the schematic diagram of an integrated circuit for Fig. 4 is partly circuit integrated.
[embodiment]
Below in conjunction with the drawings and specific embodiments, the capacitive microphone device of anti-radio frequency interference described in the utility model is described further.
[primary clustering symbol description]
Embodiment 1
Fig. 2 is the embodiment circuit diagram of the capacitive microphone device of anti-radio frequency interference described in the utility model.Capacitive microphone device comprises that an electrode EL, a field-effect transistor FET, one filter resistance R 1, a pair of shunt capacitance C1, C2 and a RC circuit.Electrode EL one end is connected in output Term 1, and the other end is connected in earth terminal Term 2; Field-effect transistor FET is connected between output Term1 and the electrode EL, and it has a gate G and is connected in electrode EL, and a drain D is connected in output Term 1, and one source pole S is connected in earth terminal Term 2; Shunt capacitance C1, C2 are crossed between output Term 1 and the earth terminal Term 2, and the capacitance of shunt capacitance C1, C2 can be set on demand; Filter resistance R 1 and be arranged between electrode EL and the field-effect transistor FET, enter in the Electret Condencer Microphone in order to filter non-essential noise; The RC circuit is arranged between output Term 1 and the earth terminal Term 2, the RC circuit comprises a resistance R 2 and a capacitor C 3, wherein resistance R 2 is connected between field-effect transistor FET and the output Term 1, capacitor C 3 then is crossed between output Term 1 and the earth terminal Term 2, this RC circuit allows that low frequency signal passes through, but can intercept high-frequency signals and enter Electret Condencer Microphone, the described capacitive microphone device of present embodiment has preferable elimination radio frequency interference and reduces the effect of noise, simultaneously because adopt more low-cost part, so have the competitive advantage on the industry.
Fig. 3 is the schematic diagram of an integrated circuit for Fig. 2 is partly circuit integrated.In the middle of present embodiment, integrated circuit 10 is with above-mentioned field-effect transistor FET and shunt capacitance C1, in C2 is integrated in, shunt capacitance C1, C2 provides the elimination high frequency noise, to reach noise cancel effect, and by increasing a diode D1, walk to the ground connection route according to diode D1 with the guiding electrostatic induced current, so the destruction that can avoid static that circuit is caused, can make integrated circuit 10 have the function of electrostatic defending, thus, the described Electret Condencer Microphone of present embodiment will have electrostatic defending, guarantee that the performance of spare part is unlikely corrupted, Electret Condencer Microphone can effectively reduce Layout space, the volume that specific implementation is compact simultaneously.
Embodiment 2
Another embodiment circuit diagram of the capacitive microphone device of Fig. 4 anti-radio frequency interference described in the utility model.The capacitive microphone device of present embodiment only utilizes an integrated circuit 20 to be arranged between output Term 1 and the earth terminal Term 2, other functional components then all are integrated in integrated circuit 20 inside, as shown in Figure 5, Fig. 5 is the circuit diagram of the integrated circuit of Fig. 4, wherein integrated field-effect transistor FET altogether, shunt capacitance C1, C2, the diode D1 of static electrification safeguard function and filtration resistance R 1, thus, integrated circuit 20 is that functional component is fully integrated in inside, so that Electret Condencer Microphone can reduce the Layout space, and reach microminiaturized purpose.
The capacitive microphone device of the described anti-radio frequency interference of present embodiment utilizes the gate adjunction of field-effect transistor to filter resistance, in the time of can making capacitive microphone device apply to Handless, reaches the purpose of noise suppressed; Moreover, present embodiment is by the design of setting up the RC circuit, can make high-frequency noise can't enter in the capacitive microphone device, so can reach effective anti-radio frequency interference and noise interferes, and present embodiment can be with field-effect transistor, diode and shunt capacitance are integrated in an IC interior, thus, can increase the field-effect transistor antistatic effect, simultaneously compared to existing Electret Condencer Microphone product, then can reduce the Layout space effectively, use the microminiaturized purpose that reaches product, also can reach the minimizing of assembly, and cost more can be reduced, the surcharge of product is provided.
The above only is an illustrative, but not is restricted.Anyly do not break away from spirit of the present utility model and category, and it is carried out equivalent modifications or change, all should be contained in the middle of the scope of this patent.
Claims (4)
1. the capacitive microphone device of an anti-radio frequency interference is characterized in that, comprising:
One electrode, the one end is connected in an output, and the other end is connected in an earth terminal;
One field-effect transistor has a gate, one source pole and a drain, and this gate is connected with this electrode, and this source electrode is connected in this earth terminal, and this drain is connected in this output;
One electric capacity in parallel is arranged between this output and this earth terminal, and is connected to the two ends of this electrode;
One filters resistance, is arranged between the gate and this electrode of this field-effect transistor; And
One RC circuit is crossed between this output and this earth terminal.
2. the capacitive microphone device of anti-radio frequency interference as claimed in claim 1, it is characterized in that: described RC circuit comprises resistance and an electric capacity.
3. the capacitive microphone device of anti-radio frequency interference as claimed in claim 1 is characterized in that: described field-effect transistor, filter resistance and shunt capacitance is integrated into an integrated circuit.
4. the capacitive microphone device of anti-radio frequency interference as claimed in claim 3 is characterized in that: a diode is set in the described integrated circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010206700194U CN202026459U (en) | 2010-12-17 | 2010-12-17 | Radio frequency interference-free capacitance microphone apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010206700194U CN202026459U (en) | 2010-12-17 | 2010-12-17 | Radio frequency interference-free capacitance microphone apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202026459U true CN202026459U (en) | 2011-11-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010206700194U Expired - Fee Related CN202026459U (en) | 2010-12-17 | 2010-12-17 | Radio frequency interference-free capacitance microphone apparatus |
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| Country | Link |
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| CN (1) | CN202026459U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103379421A (en) * | 2012-04-28 | 2013-10-30 | 歌尔声学股份有限公司 | Working state detection method and device of digital microphone channel selection pins |
| CN108632691A (en) * | 2017-10-09 | 2018-10-09 | 北京视联动力国际信息技术有限公司 | A kind of antistatic microphone |
| CN111800717A (en) * | 2019-06-12 | 2020-10-20 | 深圳市豪恩声学股份有限公司 | Anti radio frequency interference circuit and electret microphone |
-
2010
- 2010-12-17 CN CN2010206700194U patent/CN202026459U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103379421A (en) * | 2012-04-28 | 2013-10-30 | 歌尔声学股份有限公司 | Working state detection method and device of digital microphone channel selection pins |
| CN103379421B (en) * | 2012-04-28 | 2016-01-20 | 歌尔声学股份有限公司 | The working state detecting method of digital microphone channel selecting pin and device |
| CN108632691A (en) * | 2017-10-09 | 2018-10-09 | 北京视联动力国际信息技术有限公司 | A kind of antistatic microphone |
| CN111800717A (en) * | 2019-06-12 | 2020-10-20 | 深圳市豪恩声学股份有限公司 | Anti radio frequency interference circuit and electret microphone |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20111102 Termination date: 20161217 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |