CN201766644U - Mobile phone and earphone - Google Patents
Mobile phone and earphone Download PDFInfo
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- CN201766644U CN201766644U CN2010202519161U CN201020251916U CN201766644U CN 201766644 U CN201766644 U CN 201766644U CN 2010202519161 U CN2010202519161 U CN 2010202519161U CN 201020251916 U CN201020251916 U CN 201020251916U CN 201766644 U CN201766644 U CN 201766644U
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- 238000002360 preparation method Methods 0.000 claims 1
- 239000003990 capacitor Substances 0.000 abstract description 23
- 230000000903 blocking effect Effects 0.000 description 28
- 238000010586 diagram Methods 0.000 description 5
- 238000005034 decoration Methods 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
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Abstract
The utility model provides a mobile phone and an earphone. The mobile phone comprises a base band circuit which is provided with a first audio output end and a second audio output end, wherein the first audio output end is used for outputting a first differential signal and being connected with a first receiving end of an earphone receiver, and outputting the first differential signal to the first receiving end; and the second audio output end is used for outputting a second differential signal and being connected with a second receiving end of the earphone receiver, and outputting the second differential signal to the second receiving end. In the utility model, with the scheme, POP noise generated by the charging of a bridging capacitor when the earphone connected with the mobile phone works can be eliminated.
Description
Technical Field
The utility model relates to an earphone circuit design in the cell-phone especially indicates a cell-phone and earphone.
Background
As shown in fig. 1, the earphone circuit in a general mobile phone includes: the earphone circuit part and the mobile phone baseband circuit part; the left part of the separation line is an earphone circuit part, and the right part of the separation line is a mobile phone baseband circuit part; the earphone circuit part is connected with the mobile phone baseband circuit part through a connector; wherein, earphone circuit part includes: left and right channel headphones of the stereo earphone, wherein L is a left channel headphone 11, and R is a right channel headphone 12; the mobile phone baseband circuit part comprises: the dc blocking capacitors 211 and 212, and the first audio output terminal HPH _ L and the second output terminal HPH _ R of the baseband circuit of the mobile phone; the first receiving end 111 of the left channel receiver 11 is connected to the first audio output end HPH _ L of the mobile phone baseband circuit through the blocking capacitor 211, and the second receiving end 112 of the left channel receiver 11 is connected to the second receiving end 122 of the right channel receiver 12 and grounded GND; the first receiving end 121 of the right channel receiver 12 is connected to the second audio output end HPH _ R of the baseband circuit of the mobile phone through the blocking capacitor 212; the connection mode that the first receiving end of the earphone shown in fig. 1 is connected to the audio output end of the baseband circuit, and the second receiving end is grounded may be referred to as: single-ended connection; the first audio output end HPH _ L outputs a single-ended signal to the first receiving end 111 of the left channel handset, and the second audio output end HPH _ R outputs a single-ended signal to the first receiving end 121 of the right channel handset;
in addition, the circuit principle of the single-channel earphone is the same as that of the dual-channel earphone shown in fig. 1, and only one earphone is needed to replace the dual earphones.
The above-mentioned earphone circuit shown in fig. 1 adopts the scheme that the blocking capacitors 211, 212 are connected with the mobile phone baseband circuit, when the earphone detects, the earphone power amplifier is turned on, and starts to work, the blocking capacitors 211, 212 are charged to generate POP sound, which seriously affects the use experience of the user.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model is to provide a cell-phone and earphone, the earphone during operation that can fine elimination be connected with the cell-phone, the POP sound that produces is charged by blocking direct capacitance.
In order to solve the above technical problem, an embodiment of the present invention provides a mobile phone, including:
a baseband circuit having a first audio output and a second audio output;
the first audio output end is used for outputting a first differential signal, is connected with a first receiving end of an earphone receiver and outputs the first differential signal to the first receiving end;
the second audio output end is used for outputting a second differential signal, is connected with a second receiving end of the earphone receiver and outputs the second differential signal to the second receiving end.
Wherein the earpiece includes: a left channel earphone and a right channel earphone of the stereo earphone;
the first audio output end is specifically configured to be connected to the first receiving end of the left channel headphone and the first receiving end of the right channel headphone respectively, and output the first differential signal to the first receiving end of the left channel headphone and the first receiving end of the right channel headphone respectively;
the second audio output end is specifically configured to be connected to the second receiving end of the left channel headphone and the second receiving end of the right channel headphone respectively, and output the second differential signal to the second receiving end of the left channel headphone and the second receiving end of the right channel headphone respectively.
Wherein the earpiece is: an earpiece of a mono headset;
the first audio output end is specifically configured to be connected to a first receiving end of an earphone of the mono headset and output the first differential signal to the first receiving end of the earphone of the mono headset;
the second audio output terminal is specifically configured to be connected to a second receiving terminal of the earpiece of the mono headset and output the second differential signal to the second receiving terminal of the earpiece of the mono headset.
The first audio output end is directly connected with the first receiving end, and the second audio output end is directly connected with the second receiving end; or, the first audio output end is connected with the first receiving end through a differential signal connector, and the second audio output end is connected with the second receiving end through a differential signal connector.
The differential signal connector is a pin sheet open type connector or a standard type connector.
The utility model also provides an earphone, include: the mobile phone comprises a receiver with a first receiving end and a second receiving end, wherein the first receiving end is used for being connected with a first audio output end of a baseband circuit of the mobile phone and receiving a first differential signal output by the first audio output end;
the second receiving end is used for being connected with a second audio output end of the baseband circuit of the mobile phone and receiving a second differential signal output by the second audio output end.
Wherein the earpiece includes: a left channel earphone and a right channel earphone of the stereo earphone;
the first receiving end of the left channel earphone and the first receiving end of the right channel earphone are respectively connected with the first audio output end and receive a first differential signal output by the first audio output end;
the second receiving end of the left channel earphone and the second receiving end of the right channel earphone are respectively connected with the second audio output end and receive a second differential signal output by the second audio output end.
Wherein the earpiece is: an earpiece of a mono headset;
a first receiving end of a receiver of the single-track earphone is connected with the first audio output end and receives a first differential signal output by the first audio output end;
and a second receiving end of the receiver of the single-channel earphone is connected with the second audio output end and receives a second differential signal output by the second audio output end.
The first receiving end is directly connected with the first audio output end, and the second receiving end is directly connected with the second audio output end; or, the first receiving end is connected with the first audio output end through a differential signal connector, and the second receiving end is connected with the second audio output end through a differential signal connector.
The differential signal connector is a pin sheet open type connector or a standard type connector.
The utility model discloses an above-mentioned technical scheme's beneficial effect as follows:
in the scheme, the direct current blocking capacitors of the mobile phone baseband circuit part are removed, the earphones of the earphones are connected with the audio output end of the mobile phone baseband circuit part, and differential signals are output to the earphones of the earphones through the audio output end, so that POP sounds generated by charging of the direct current blocking capacitors can not be generated when the earphones start to work.
Drawings
FIG. 1 is a diagram illustrating a connection relationship between a stereo headphone circuit and a mobile phone baseband circuit in the prior art;
fig. 2 is a connection relationship diagram of the stereo headphone circuit and the mobile phone baseband circuit of the present invention;
fig. 3 is a connection diagram of the monaural headset circuit and the mobile phone baseband circuit according to the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.
The utility model discloses in to prior art, at earphone during operation, because the problem that produces the POP sound that the blocking electric capacity charges provides a cell-phone and earphone, can fine elimination with the earphone during operation that the cell-phone is connected, blocking electric capacity charges the POP sound that produces.
The utility model discloses a mobile phone, include: a baseband circuit having a first audio output and a second audio output; the first audio output end is used for outputting a first differential signal, is connected with a first receiving end of an earphone receiver and outputs the first differential signal to the first receiving end;
the second audio output end is used for outputting a second differential signal, is connected with a second receiving end of the earphone receiver and outputs the second differential signal to the second receiving end.
The first receiving end and the second receiving end of the earphone are both connected with the audio output end of the baseband circuit, and the audio output end outputs differential signals to the connection mode of the first receiving end and the second receiving end, which can be called as: differential connection; wherein, the "differential signal" is a pair of symmetrical signals with equal size and opposite polarity, and the differential signal is used for transmitting useful signals;
the utility model discloses a this mobile phone embodiment gets rid of through the blocking electric capacity with mobile phone baseband circuit part to with the connected mode of earphone and mobile phone baseband circuit part's audio output end, connect by single-ended and change into the difference and connect, at the earphone during operation, owing to not having blocking electric capacity, consequently, can not reproduce the POP sound that produces owing to blocking electric capacity charges, just the utility model discloses a this embodiment, relative prior art has still used two blocking electric capacities less, and consequently, the mobile phone cost has also reduced, and has saved the hardware space of mobile phone baseband design.
Fig. 2 is a diagram showing the connection relationship between the stereo headphone circuit and the baseband circuit of the mobile phone according to the above embodiment;
the earpiece includes: a left channel headphone 31 and a right channel headphone 32 of the stereo headphone;
the first audio output end HPH _ L is specifically configured to be connected to the first receiving end 311 of the left channel earpiece 31 and the first receiving end 321 of the right channel earpiece 32, respectively, and output the first differential signal to the first receiving end 311 of the left channel earpiece 31 and the first receiving end 321 of the right channel earpiece 32, respectively;
the second audio output end HPH _ R is specifically configured to be connected to the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32, respectively, and output the second differential signal to the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32, respectively.
In this embodiment, after the first audio output end HPH _ L of the baseband circuit is connected to the first receiving end 311 of the left channel handset 31 and the first receiving end 321 of the right channel handset 32, the direct current components in the differential signals output by the HPH _ L ends received by the first receiving end 311 of the left channel handset 31 and the first receiving end 321 of the right channel handset 32 cancel each other;
similarly, after the second audio output end HPH _ R of the baseband circuit is connected to the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32, the direct current components in the differential signals output by the HPH _ R ends received by the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32 cancel each other;
therefore, a direct current blocking capacitor is not needed, so that POP sound caused by charging of the direct current blocking capacitor is avoided, and in the embodiment, the HPH _ L, HPH _ R output is configured into differential output in the design of mobile phone drive;
in the embodiment of the stereo earphone, the direct current blocking capacitor is removed from the baseband circuit part of the mobile phone, the connection mode of the earphone receiver and the audio output end of the baseband circuit is changed from single-ended connection to differential connection, and the left and right sound channel outputs of the earphone are configured into differential output by the mobile phone driving part, so that POP sound generated by charging of the direct current blocking capacitor when the mobile phone earphone works is avoided, meanwhile, the cost of the mobile phone is reduced because two direct current blocking capacitors are used less, the two capacitors are usually very large, and the hardware space designed by the baseband of the mobile phone is saved.
As shown in fig. 3, it is a connection relationship diagram between the monaural headset circuit and the handset baseband circuit in the above embodiment;
the telephone receiver is as follows: an earpiece of a mono headset;
the first audio output port HPH _ L is specifically configured to be connected to the first receiving port 411 of the earpiece 41 of the mono headset, and output the first differential signal to the first receiving port 411 of the earpiece 41 of the mono headset;
the second audio output port HPH _ R is specifically configured to be connected to the second receiving port 412 of the earpiece 41 of the mono headset, and output the second differential signal to the second receiving port 412 of the earpiece 41 of the mono headset.
Thus, the dc components in the HPH _ L, HPH _ R differential signals received by the first receiving end 411 and the second receiving end 412 are cancelled, so that no dc blocking capacitor is needed, and therefore, no POP sound caused by charging of the dc blocking capacitor is generated, and the embodiment of the mono headset further includes: the HPH _ L, HPH _ R output is configured into a differential output in the design of the mobile phone driver.
In addition, in all the above embodiments, the first audio output terminal is identified by HPH _ L in the figure, but is not limited to HPH _ L; the second audio output is identified in the figure by, but not limited to, HPH _ R; those skilled in the art will understand that the first audio output terminal can also be referred to as HPH _ R, but at this time, the second audio output terminal should be HPH _ L as long as they correspond to the left and right earphones of the two-channel earphone respectively;
in addition, in all the above embodiments, the first audio output terminal is directly connected to the first receiving terminal, and the second audio output terminal is directly connected to the second receiving terminal; or,
the first audio output end is connected with the first receiving end through a differential signal connector, and the second audio output end is connected with the second receiving end through a differential signal connector;
wherein the differential signal connector is: a wafer-in-wafer open type connector or a standard type connector.
As shown in fig. 2 and 3, the present invention further provides an earphone embodiment:
the earphone includes: an earpiece having a first receiving end and a second receiving end, wherein,
the first receiving end is used for being connected with a first audio output end of a baseband circuit of a mobile phone and receiving a first differential signal output by the first audio output end;
the second receiving end is used for being connected with a second audio output end of the baseband circuit of the mobile phone and receiving a second differential signal output by the second audio output end;
in the embodiment of the earphone, the direct current blocking capacitor of the mobile phone baseband circuit part is removed, the connection mode of the earphone receiver and the audio output end of the mobile phone baseband circuit part is changed from single-ended connection to differential connection, so that POP sound generated by charging of the direct current blocking capacitor can not be generated when the earphone starts to work, and compared with the prior art, two direct current blocking capacitors are omitted, so that the cost of the mobile phone is reduced, and the hardware space of the mobile phone baseband design is saved.
Specifically, as shown in fig. 2, a left channel earpiece 31 and a right channel earpiece 32 of the stereo headphone;
the first receiving terminal 311 of the left channel earpiece 31 and the first receiving terminal 321 of the right channel earpiece 32 are respectively connected to the first audio output terminal HPH _ L, and receive the first differential signal output by the first audio output terminal HPH _ L;
the second receiving end 312 of the left channel earphone 31 and the second receiving end 322 of the right channel earphone 32 are respectively connected to the second audio output end HPH _ R, and receive the second differential signal output by the second audio output end HPH _ R.
In this embodiment of the stereo headphone, after the first receiving end 311 of the left channel headphone 31 and the first receiving end 321 of the right channel headphone 32 are connected to the first audio output end HPH _ L of the baseband circuit, the direct current components in the differential signals output from the HPH _ L ends received by the first receiving end 311 of the left channel headphone 31 and the first receiving end 321 of the right channel headphone 32 cancel each other;
similarly, after the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32 are connected to the second audio output end HPH _ R of the baseband circuit, the dc components in the differential signals output from the HPH _ R ends received by the second receiving end 312 of the left channel handset 31 and the second receiving end 322 of the right channel handset 32 cancel each other;
therefore, the direct current blocking capacitor is not needed, so that the POP sound caused by charging of the direct current blocking capacitor is avoided, and in the embodiment, the HPH _ L, HPH _ R output is further configured to be a differential output in the design of the mobile phone driver.
As shown in fig. 3, the handset is: an earpiece 41 of a mono headset;
the first receiving terminal 411 of the receiver 41 of the mono headset is connected to the first audio output terminal HPH _ L, and receives the first differential signal output by the first audio output terminal HPH _ L;
the second receiving terminal 412 of the receiver 41 of the mono headset is connected to the second audio output terminal HPH _ R and receives the second differential signal output by the second audio output terminal HPH _ R.
In this embodiment of the monaural headset, similarly, by connecting the first receiving terminal 411 and the second receiving terminal 412 to HPH _ L and HPH _ R respectively, the dc components in the received HPH _ L, HPH _ R differential signal are mutually cancelled, so that no dc blocking capacitor is needed, and therefore there is no POP sound caused by charging of the dc blocking capacitor, and this embodiment of the monaural headset further includes: the HPH _ L, HPH _ R output is configured into a differential output in the design of the mobile phone driver.
In addition, in all the above embodiments of the earphone, the first receiving terminal is directly connected to the first audio output terminal, and the second receiving terminal is directly connected to the second audio output terminal; or,
the first receiving end is connected with the first audio output end through a differential signal connector, and the second receiving end is connected with the second audio output end through a differential signal connector;
the differential signal connector is a pin sheet open type connector or a standard type connector.
The above embodiments of the present invention relate to the receiving part (receiver) of the earphone, the transmitting part (microphone) is the same as the common design, the earphone solution of the above embodiments may have the microphone, or may not have the microphone; wherein, when the microphone is provided, a grounding wire is also needed.
The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. A handset, comprising:
a baseband circuit having a first audio output and a second audio output; it is characterized in that the preparation method is characterized in that,
the first audio output end is used for outputting a first differential signal, is connected with a first receiving end of an earphone receiver and outputs the first differential signal to the first receiving end;
the second audio output end is used for outputting a second differential signal, is connected with a second receiving end of the earphone receiver and outputs the second differential signal to the second receiving end.
2. The handset according to claim 1, wherein the earpiece comprises: a left channel earphone and a right channel earphone of the stereo earphone;
the first audio output end is specifically configured to be connected to the first receiving end of the left channel headphone and the first receiving end of the right channel headphone respectively, and output the first differential signal to the first receiving end of the left channel headphone and the first receiving end of the right channel headphone respectively;
the second audio output end is specifically configured to be connected to the second receiving end of the left channel headphone and the second receiving end of the right channel headphone respectively, and output the second differential signal to the second receiving end of the left channel headphone and the second receiving end of the right channel headphone respectively.
3. The handset according to claim 1, wherein the earpiece is: an earpiece of a mono headset;
the first audio output end is specifically configured to be connected to a first receiving end of an earphone of the mono headset and output the first differential signal to the first receiving end of the earphone of the mono headset;
the second audio output terminal is specifically configured to be connected to a second receiving terminal of the earpiece of the mono headset and output the second differential signal to the second receiving terminal of the earpiece of the mono headset.
4. The mobile phone of claim 1, wherein the first audio output is directly connected to the first receiving end, and the second audio output is directly connected to the second receiving end; or, the first audio output end is connected with the first receiving end through a differential signal connector, and the second audio output end is connected with the second receiving end through a differential signal connector.
5. The handset of claim 4, wherein the differential signal connector is a pin strip open type connector or a standard type connector.
6. An earphone, comprising: an earpiece having a first receiving end and a second receiving end, wherein,
the first receiving end is used for being connected with a first audio output end of a baseband circuit of a mobile phone and receiving a first differential signal output by the first audio output end;
the second receiving end is used for being connected with a second audio output end of the baseband circuit of the mobile phone and receiving a second differential signal output by the second audio output end.
7. The headset of claim 6, wherein the earpiece comprises: a left channel earphone and a right channel earphone of the stereo earphone;
the first receiving end of the left channel earphone and the first receiving end of the right channel earphone are respectively connected with the first audio output end and receive a first differential signal output by the first audio output end;
the second receiving end of the left channel earphone and the second receiving end of the right channel earphone are respectively connected with the second audio output end and receive a second differential signal output by the second audio output end.
8. The headset of claim 6, wherein the earpiece is: an earpiece of a mono headset;
a first receiving end of a receiver of the single-track earphone is connected with the first audio output end and receives a first differential signal output by the first audio output end;
and a second receiving end of the receiver of the single-channel earphone is connected with the second audio output end and receives a second differential signal output by the second audio output end.
9. The headphone of claim 6, wherein the first receiving end is directly connected to the first audio output end, and the second receiving end is directly connected to the second audio output end; or, the first receiving end is connected with the first audio output end through a differential signal connector, and the second receiving end is connected with the second audio output end through a differential signal connector.
10. The headset of claim 9, wherein the differential signal connector is a pin strip open type connector or a standard type connector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202519161U CN201766644U (en) | 2010-06-29 | 2010-06-29 | Mobile phone and earphone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202519161U CN201766644U (en) | 2010-06-29 | 2010-06-29 | Mobile phone and earphone |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201766644U true CN201766644U (en) | 2011-03-16 |
Family
ID=43719253
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010202519161U Expired - Fee Related CN201766644U (en) | 2010-06-29 | 2010-06-29 | Mobile phone and earphone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201766644U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107615741A (en) * | 2015-10-30 | 2018-01-19 | 华为技术有限公司 | The interlock circuit and method of a kind of Echo Cancellation |
-
2010
- 2010-06-29 CN CN2010202519161U patent/CN201766644U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107615741A (en) * | 2015-10-30 | 2018-01-19 | 华为技术有限公司 | The interlock circuit and method of a kind of Echo Cancellation |
| CN107615741B (en) * | 2015-10-30 | 2020-04-14 | 华为技术有限公司 | Echo cancellation related circuit and method |
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| Date | Code | Title | Description |
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| 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: 20110316 Termination date: 20160629 |
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| CF01 | Termination of patent right due to non-payment of annual fee |