GB2569809A

GB2569809A - An apparatus, method and computer program for controlling an audio transducer

Info

Publication number: GB2569809A
Application number: GB1721972.6A
Authority: GB
Inventors: Ozcan Koray; Tapani Vilermo Miikka; Tossavainen Antero
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2017-12-27
Filing date: 2017-12-27
Publication date: 2019-07-03
Also published as: GB201721972D0; WO2019129918A1

Abstract

An apparatus 1 comprising: an audio transducer 3; a two-dimensional sensing portion 5; and electronic circuitry 3. In operation the sensing portion detects one or more operating conditions of the loudspeaker and provides an output signal to the electronic circuitry which uses said signal to control the audio signal. The two dimensional material comprises at least one of: graphene; graphene oxide; reduced graphene oxide; functionalized graphene; molybdenum disulphide; tungsten disulphide; or boron nitride. The sensing portion may be inside the loudspeaker and provide an indication of a change in conductivity of the two-dimensional material in response to operating conditions of the audio transducer such as temperature, humidity, light or analytes in one or more parts of the loudspeaker. The 2D sensing material (9, Fig. 5) may comprise a conductive material coupled to a voice coil; diaphragm (21, Fig. 5); magnet (31, Fig. 5); or bottom plate of the loudspeaker. The sensing portion may also provide a heat sink function. Control of the audio signal may comprise adjusting the driving voltage.

Description

TECHNOLOGICAL FIELD

Examples of the disclosure relate to an apparatus, method and computer program for controlling an audio transducer. In particular, they relate to an apparatus, method and computer program for controlling an audio transducer using information obtained from a sensing portion.

BACKGROUND

Apparatus comprising audio transducers are known. The audio transducers are configured to transduce an audio signal into a sound output signal. Different operating conditions may affect the performance of the audio transducer, these operating conditions therefore need to be taken into account.

BRIEF SUMMARY

According to various, but not necessarily all, examples of the disclosure, there is provided an apparatus comprising: an audio transducer configured to transduce an audio signal into a sound output signal; a sensing portion comprising two dimensional material wherein the sensing portion is positioned, at least partially, within the apparatus so as to enable one or more operating conditions of the audio transducer to be determined and provide an output signal based on the one or more operating conditions; and an output terminal configured to provide the output signal from the sensing portion to electronic circuitry so as to enable the electronic circuitry to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

Controlling the audio signal provided to the transducer may comprise adjusting a driving voltage level of the transducer.

The sensing portion may be provided inside the audio transducer. The sensing portion may be configured inside the audio transducer to enable operating conditions of one or more parts of the audio transducer to be determined.

The electronic circuitry may be provided, at least partially, within the apparatus.

The audio transducer may comprise a voice coil and the two dimensional material may be coupled the voice coil.

The audio transducer may comprise a diaphragm and the two dimensional material may be coupled to the diaphragm.

The audio transducer may comprise a magnet and the two dimensional material may be coupled to the magnet.

The audio transducer may comprise a bottom plate and the two dimensional material may be coupled to the bottom plate.

The sensing portion may be positioned within the apparatus to provide a heat sink for the audio transducer.

The two dimensional material may comprise a conductive material.

The two dimensional material may comprise at least one of: graphene, graphene oxide, reduced graphene oxide, functionalized graphene, molybdenum disulphide, tungsten disulphide, boron nitride.

The output signal of the sensing portion may provide an indication of a change in conductivity of the two dimensional material in response to operating conditions of the audio transducer.

The operating conditions of the audio transducer may comprise at least one of; temperature, humidity, light, analytes.

The electronic circuitry may be configured to process an audio input signal and the output signal from the sensing portion so as to provide a modified audio signal to the audio transducer.

According to various, but not necessarily all, examples of the disclosure, there is provided an apparatus comprising: audio means configured to transduce an audio signal into a sound output signal; sensing means comprising two dimensional material wherein the sensing means is positioned, at least partially, within the apparatus so as to enable one or more operating conditions of the audio means to be determined and provide an output signal based on the one or more operating conditions; and output means configured to provide the output signal from the sensing means to control means so as to enable the control means to control the audio signal provided to the audio means based on the output signal from the sensing means.

According to various, but not necessarily all, examples of the disclosure, there is provided an apparatus comprising: means for obtaining an audio input signal; means for obtaining an electrical output signal from a sensing portion where the sensing portion comprises two dimensional material and is positioned within an apparatus comprising an audio transducer so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the determined one or more operating conditions; and means for processing the audio input signal so as to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

According to various, but not necessarily all, examples of the disclosure, there is provided an electronic device comprising an apparatus as described above.

According to various, but not necessarily all, examples of the disclosure, there is provided a method comprising: obtaining an audio input signal; obtaining an electrical output signal from a sensing portion where the sensing portion comprises two dimensional material and is positioned within an apparatus comprising an audio transducer so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the determined one or more operating conditions; and processing the audio input signal so as to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

According to various, but not necessarily all, examples of the disclosure, there is provided a computer program comprising computer program instructions that, when executed by processing circuitry, cause obtaining an audio input signal; obtaining an electrical output signal from a sensing portion where the sensing portion comprises two dimensional material and is positioned within an apparatus comprising an audio transducer so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the determined one or more operating conditions; and processing the audio input signal so as to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

According to various, but not necessarily all, examples of the disclosure, there is provided an audio transducer comprising; a first terminal configured to receive an audio signal to enable the audio transducer to transduce the audio signal into a sound output signal; a sensing portion comprising two dimensional material wherein the sensing portion is positioned within the apparatus so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the one or more operating conditions; and a second terminal configured to provide the output signal from the sensing portion.

The second terminal may be configured to enable the output signal from the sensing portion to be provided to electronic circuitry to enable the electronic circuitry to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

BRIEF DESCRIPTION

For a better understanding of various examples that are useful for understanding the detailed description, reference will now be made by way of example only to the accompanying drawings in which:

Fig. 1 illustrates an apparatus;

Fig. 2 illustrates an audio transducer;

Fig. 3 illustrates a portion of an audio transducer;

Fig. 4 illustrates a cross section of an audio transducer;

Fig. 5 illustrates a portion of an audio transducer;

Fig. 6 illustrates an electronic device comprising an apparatus;

Figs. 7A to 7C illustrate example apparatus;

Fig. 8 illustrates example electronic circuitry;

Fig. 9 illustrates an example method; and

Fig. 10 illustrates example electronic circuitry.

DETAILED DESCRIPTION

Examples of the disclosure relate to an apparatus 1 comprising an audio transducer 3. The apparatus 1 comprises a sensing portion 5 which is positioned within the apparatus 1 so that it can sense operating conditions within the audio transducer 3. The operating conditions could be the temperature of parts of the audio transducer 3, the humidity levels within the audio transducer 3 or any other suitable parameters which may affect the operation of the audio transducer 3. The apparatus 1 is configured to provide an output signal 11 from the sensing portion 5 to electronic circuitry 7 to enable the information obtained from the sensing portion 5 to be used to control an audio signal 15 provided to the audio transducer 3. The audio signal 15 may be controlled so as to improve the audio quality for the internal operating conditions of the audio transducer 3 or to prevent damage to the audio transducer 3 or for any other purpose.

Fig. 1 schematically illustrates an apparatus 1 according to examples of the disclosure. The example apparatus 1 comprises an audio transducer 3, a sensing portion 5 and an output terminal 12 configured to provide an output signal 13 to electronic circuitry 7.

The audio transducer 3 may comprise any means which may be configured to transduce an audio signal 15 into a sound output signal 17. The audio transducer 3 may comprise a loudspeaker, a hands free speaker, an earpiece speaker or any other suitable type of transducer. Examples of audio transducers 3 are shown in Figs. 2 to 4.

The apparatus 1 also comprises a sensing portion 5. The sensing portion 5 is positioned within the apparatus 1 so as to enable one or more operating conditions of the audio transducer 3 to be detected. In some examples the sensing portion 5 may be provided within the audio transducer 3. In some examples the sensing portion 5 could be entirely provided within the audio transducer 3. In other examples the sensing portion 5 could be partially provided within the audio transducer 3 and/or partially provided within the apparatus 1. In some examples the sensing portion 5 may be coupled to one or more components of the audio transducer 3.

The sensing portion 5 comprises two dimensional material 9. The sensing portion 5 may comprise one or more layers of two dimensional material 9. In the example of Fig. 1 the sensing portion 5 comprises a layer of two dimensional material 9 provided coupled to the audio transducer 3.

The two dimensional material 9 may comprise any suitable material which provides a measureable electrical output signal 13 in response to an incident parameter 11. In some examples the two dimensional material 9 may comprise a conductive material which may change conductivity in response to the incident parameter 11.

The two dimensional material 9 may be configured within the audio transducer 3, or other components of the apparatus 1, so as to enable changes in the electrical properties of the two dimensional material 9 to be detected. In some examples the two dimensional material 9 may be provided as a channel in a transistor such as a field effect transistor. In such examples the two dimensional material 9 may be provided between a source electrode and drain electrode so as to enable the conductivity of the two dimensional material 9 to be measured. In some examples a gate electrode may be electrically coupled to the two dimensional material 9 so as to improve the sensitivity of the field effect transistor.

The two dimensional material 9 may comprise a very thin layer of material. In some examples the two dimensional material 9 could be an atomic monolayer. In some examples the two dimensional material 9 could comprise several atomic monolayers. The two dimensional material 9 may be thin relative to the membrane of the audio transducer 3. In some examples the two dimensional material 9 may be several orders of magnitude thinner than the membrane of the audio transducer 3.

In some examples the two dimensional material 9 may comprise a material which is strong enough so that it can be deformed and/or subjected to strain. For example, where the two dimensional material 9 is coupled to a membrane or other moveable portion of the audio transducer 3 the two dimensional material 9 may move and flex during the detection of the sound signal. In such cases the two dimensional material 9 must be strong enough such that deformation does not cause failure or other damage to the two dimensional material 9.

In some examples the two dimensional material 9 could comprise graphene. In some examples the two dimensional material 9 could comprise a graphene based material such as graphene oxide or reduced graphene oxide. In some examples the two dimensional material 9 could comprise molybdenum disulphide, tungsten disulphide, boron nitride or any other suitable material or combinations of these materials.

In some examples the two dimensional material 9 may comprise functionalized graphene. The graphene could be functionalized using colloidal quantum dots, metallic nanoparticles, bio-functional molecules or any other suitable means. The means that is used to functionalize the graphene may depend on the parameter and/or parameters 11 that the sensing portion 5 is intended to sense.

In some examples the two dimensional material 9 may comprise a plurality of layers of two or more different materials. For example, it may comprise a membrane of graphene oxide supporting a layer of reduced graphene oxide or any other suitable material.

In some examples the two dimensional material 9 could be configured into a three dimensional structure. For example, graphene may be configured into carbon nanotubes or other suitable structures. In some examples the two dimensional material 9 could be integrated into a three dimensional structure. For example a three dimensional structure could be coated with the two dimensional material 9 or may have the two dimensional material 9 provided within the three dimensional structure.

The operating conditions of the audio transducer 3 may comprise one or more parameters 11 that can be sensed by the two dimensional material 9. The parameter 11 may comprise any conditions within the apparatus 1 and/or within the environment of the apparatus 1. In particular the parameter 11 may comprise any measurable conditions which may affect the performance or functioning of the audio transducer 3. For example the parameter 11 could comprise at least one of temperature, humidity, analytes and/or a combination of any of these. The analytes could comprise a particular chemical or chemical species.

The parameter 11 causes a change in conductivity of the two dimensional material 9 which causes an output signal 13 to be provided. The output signal 13 provides an indication of the parameter 11. The output signal 13 may provide an indication of the type of parameter 11 and/or the quantity of the parameter 11. The output signal 13 may be provided to electronic circuitry 7 to enable the electronic circuitry 7 to process and/or store the electrical output signal 13. This therefore enables the operating conditions of the audio transducer 3 to be determined.

In some examples the change in conductivity of the two dimensional material 9 may be a permanent change in conductivity and/or may last even when the parameter 11

is removed.	This enables information about the internal conditions to which the two
dimensional	material 9 has been exposed to be stored in the two dimensional
material 9.	This may enable historical information to be obtained about the

environments that the apparatus 1 has been exposed to or the historical operating conditions of the apparatus 1.

The apparatus 1 also comprises an output terminal 12 configured to provide an output signal 13 to electronic circuitry 7. In some examples the electronic circuitry 7 may be provided within, or at least partially within the apparatus 1. In other examples the electronic circuitry 7 could be provided external to the apparatus 1.

The electronic circuitry 7 may comprise means for controlling the audio transducer 3. In some examples the electronic circuitry 7 may comprise means for controlling other components within the apparatus 1.

The electronic circuitry 7 is configured to provide an audio signal 15 to the audio transducer 3. The audio signal 15 controls the sound output signal 17 that is provided by the audio transducer 3.

The electronic circuitry 7 is also coupled to the output terminal to enable the electronic circuitry 7 to receive an electrical output signal 13 from the sensing portion 5. The electrical output signal 13 is indicative of the parameter 11 that is sensed by the sensing portion 5. The electronic circuitry 7 may be configured to use the electrical output signal 13 from the sensing portion 5 to control the audio signal 15 provided to the audio transducer 3. This may enable the audio signal 15 to be adapted to take into account the current operating conditions or other environmental factors of the audio transducer 3. This may help to optimize the sound output 17 of the audio transducer 3.

Fig. 2 illustrates an example audio transducer 3 which may be used in some examples of the disclosure. The audio transducer 3 may be provided separately to the electronic circuitry 7.

The audio transducer 3 comprises a chassis 20, a diaphragm 21, a suspension 23, a coil wire 25, a contact 27, a voice coil 29, a bottom plate 30 and a magnet 31. The example audio transducer 3 in Fig. 2 is a conventional moving coil loudspeaker. In alternative embodiments the audio transducer 3 can be an active loudspeaker which may also comprise the electronic circuitry 7.

The chassis 20 provides a housing for the audio transducer 3. The suspension 23 provides a flexible member that couples the diaphragm 21 to the chassis 20. The suspension 23 enables the diaphragm 21 to move relative to the chassis 20. The voice coil 29 surrounds the magnet 31. The voice coil 29 and the magnet 31 are provided underneath the diaphragm 21 to enable the voice coil 29 to drive the diaphragm 21. The bottom plate 30 is provided underneath the magnet 31 and the voice coil 29. The coil wire 25 is coupled to the contact 27 and the voice coil 29. The contact 27 may be electrically connected to a PWB. The coil wire 25 and the contact 27 may enable the voice coil 25 to be electrically connected to electronic circuitry 7 to enable the electronic circuitry 7 to control the audio transducer 3.

The audio transducer 3 may also comprise at least one first terminal and at least one second terminal. The at least one first terminal may be configured to receive an audio signal to enable the audio transducer 3 to transduce the audio signal into a sound output signal 17. The at least one second terminal may be an output terminal. The at least one second terminal may be configured to provide the output signal 13 from the sensing portion 5. The at least one second terminal may enable the output signal 13 from the sensing portion 5 to be provided to electronic circuitry 7

Fig. 3 illustrates a portion of the audio transducer 3. Fig. 3 shows the intersection between the voice coil 29 and the diaphragm 21 and the coil wire 25 in more detail.

Fig. 4 illustrates a cross section of an audio transducer 3 and indicates possible locations for the two dimensional material 9 of the sensing portion 5.

The sensing portion 5 may be provided within the audio transducer 3. The sensing portion 5 may be provided within the chassis 20 and may be coupled to any components of the audio transducer 3. The position of the sensing portion 5 may be selected based on the parameter 11 that the sensing portion 5 is intended to detect, the type of two dimensional material 9 used within the sensing portion 5 and/or any other suitable factor.

in some examples the sensing portion 5 may be configured to detect the temperature of the audio transducer 3, one or more parts of the audio transducer 3, or the temperature inside the audio transducer 3. The temperature inside the audio transducer 3 may be increased by the operation of the transducer 3. In such examples the sensing portion 5 may be coupled to the components of the audio transducer 3 that heat up first during operation of the audio transducer 3 and/or the components which are most likely to cause degradation of performance due to a high temperature, or fail due to a high temperature. For instance, the sensing portion 5 could comprise two dimensional material coupled to the voice coil 29, the contact 27, the coil wire 25 or the magnet 31.

In some examples the two dimensional material 9 may be coupled to the diaphragm

21. For instance, a layer of two dimensional material 9 may be coated on a surface 33 of the diaphragm 21. The surface 33 could be the upper surface or the lower surface of the diaphragm 21. In such examples the layer of two dimensional material 9 must be thin enough to enable the diaphragm 21 to move but thick enough to enable a measurable electrical output to be provided in response to a parameter 11.

In some examples the two dimensional material 9 may be coupled to the voice coil

29. For instance, the two dimensional material 9 could be provided as a coating on the surface 35 of the voice coil 29.

In some examples the two dimensional material 9 may be coupled to the bottom plate 30. For instance, the two dimensional material 9 could be provided as a coating on one or more of the lower surface 36 of the bottom plate 30, on an inner surface 38 of the bottom plate 30 or on an upper surface 39 of the bottom plate 30 so that the two dimensional material 9 is provided between the bottom plate 30 and the magnet 31.

In some examples the two dimensional material 9 may be coupled to the magnet 31. For instance, a layer of two dimensional material 9 may be coated on the upper surface 34 of the magnet 31.

In some examples the two dimensional material 9 could be coupled to more than one component. For instance, the two dimensional material 9 could be provided as a flexible member 37 between the magnet 31 and the diaphragm 21. In this case the two dimensional material 9 could be coupled to both magnet 31 and the diaphragm

21. The flexible member 37 could comprise two dimensional material 9 configured to detect a parameter 11 but may be flexible enough so as to allow movement of the diaphragm relative to the magnet 31.

In some examples the two dimensional material 9 could be provided as a thin layer overlaying one or more components of the audio transducer 3. For example the two dimensional material 9 could be provided overlaying a diaphragm 21 so that a multilayered diaphragm 21 is provided. In other examples one or more components of the audio transducer 3 may be formed from the two dimensional material 9. For example, the diaphragm 21 could be formed from the two dimensional material 9.

Fig. 5 illustrates a portion of an audio transducer 3. In the example of Fig. 5 the two dimensional material is coated on the outer surface 35 of the voice coil 29. It is to be appreciated that other locations may be used for the two dimensional material 9 in other examples of the disclosure.

Fig. 6 illustrates an electronic device 61 comprising an apparatus 1. The electronic device 61 also comprises a device chassis 63 and a printed wiring board (PWB) 65. The electronic device 61 could be a communications device such as a mobile telephone or any other suitable type of device comprising one or more audio transducers 3.

The chassis 63 may provide rigid or structural support for the electronic device 61. The chassis 63 may comprise a thermally conductive material such as a metal. The PWB 65 may provide support for the components of electronic device 61. The PWB may provide a support for the audio transducer 3 and the electronic circuitry 7 of the apparatus 1.

In the example of Fig. 6 the sensing portion 5 is provided within the audio transducer 3. The sensing portion 5 is shown as being coupled to the magnet 31 of the transducer 3 however it is to be appreciated that the sensing portion 5 could be provided at any suitable location within the audio transducer 3.

In the example of Fig. 6 the sensing portion 5 may also provide a heat sink for the audio transducer 3. In such examples the sensing portion 5 may provide a dual function as both a sensing portion 5 and a heat sink. The two dimensional material 9 within the sensing portion 5 may be configured to direct heat from the audio transducer 3 to the other components of the electronic device 61. The two dimensional material 9 may be configured to direct the heat towards cooler parts of the electronic device 61.

In the example of Fig. 6 the heat is conducted from the audio transducer 3 to the PWB 65 and from the PWB 65 to the chassis 63 as these components have a lower temperature than the components of the audio transducer. This may enable the cooling of the audio transducer 3.

The sensing portion 5 may be positioned so as to avoid heat being provided from warmer components of the electronic device 61 to the audio transducer 3. For example the main processing circuitry of the electronic device 61 may have a higher temperature than the audio transducer 3. In such cases the sensing portion 5 would not be provided between the main processing circuitry and the audio transducer 3.

Figs. 7A to 7C schematically illustrate example apparatus 1 in which the information obtained by the sensing portion 5 is used to control the audio signal 15 provided to the audio transducer 3. The control of the audio signal 15 may comprise adjusting the audio signal 15. For example it may comprise decreasing the power levels within the audio signal 15 to prevent any damage to the audio transducer 3. In some examples the control of the audio signal 15 may comprises adjusting the equalization, changing the settings for the dynamic range controller or any other suitable changes. In some examples the control of the audio signal might not require any adjustment of the audio signals. For example, if it is determined that the operating conditions are within standard operating conditions and it is unlikely that the audio transducer 3 will be damaged then there would be no need to decrease the power levels in the audio signal 15.

In each of Figs. 7A to 7C the apparatus 1 comprises an audio transducer 3, a sensing portion 5, electronic circuitry 7 and a power amplifier 71. The audio transducer 3, sensing portion 5 and electronic circuitry 7 may be as described above.

The power amplifier 71 may comprise any means which may be configured to modify the power in an electronic signal. In the example of Figs. 7A to 7C the power amplifier 71 is shown as a separate component to the electronic circuitry 7. In other examples the electronic circuitry 7 and the power amplifier 71 could be integrated into a single component.

In the examples of Figs. 7A to 7C the electronic circuitry 7 obtains an audio input signal 73 and processes the audio input signal 73 to provide a processed audio signal 75. The processing performed on the audio input signal 73 may comprise any suitable type of processing, for example it may optimize the audio input signal for the type of audio transducer 3, or for the type of audio that is provided or may provide spatial audio or any other suitable type of audio processing.

The processed audio signal 75 is provided to the power amplifier 71 which amplifies the processed audio signal 75 to provide the audio signal 15.

The audio signal 15 is provided to the audio transducer 3 which transduces the audio signal 15 to provide a sound output signal 17. Therefore the electronic circuitry 7 control the sound output signal 17 that is provided by the audio transducer 3.

In each of the examples of Figs. 7A to 7C the apparatus 1 comprises a sensing portion 5. The sensing portion 5 is configured to provide an electrical output signal 13 to the electronic circuitry 7. The electrical output signal 13 provides information relating to the parameters 11 detected by the sensing portion 5 and so provides an indication of the current environment and operating conditions of the audio transducer 3. This enables the electronic circuitry to control the audio signal based on the electrical output signal 13 from the sensing portion 5. This enables the electronic circuitry 7 to use current information about the environment and operating conditions of the audio transducer 3 when processing the audio input signal 73. For example, it may use information about the current temperature within the audio transducer 3 to modify the power levels within the audio signal 15. The modified power levels may be limited so as to prevent the temperature of components of the audio transducer 3 from reaching above a given threshold. This may prevent components of the audio transducer 3 from being damaged by an increase in temperature.

The information of the current environment and/or operating conditions of the audio transducer 3 may also be used to increase the quality of the sound output 17. Different operating conditions such as different temperatures and different humidity levels may affect the response of the audio transducer 3. In examples of the disclosure, the electronic circuitry 7 obtains information about the current operating conditions and uses this to modify the processed audio signal 75 so that the audio signal 15 can be optimized or adjusted for the current conditions.

The sensing portion 5 is provided in different positions within each of the examples of Fig. 7A to 7C. In the example of Fig. 7A the sensing portion 5 is provided coupled to the terminals of the audio transducer 3. This may enable the terminals of the audio transducer 3 to be used to enable the electrical output signal 13 to be provided to the electronic circuitry 7. In the example of Fig. 7A the electrical output signal 13 bypasses the power amplifier 71.

In the example of Fig. 7B the sensing portion 5 is also provided coupled to the terminals of the audio transducer 3. However in the example of Fig. 7B the electrical output signal 13 is provided to the electronic circuitry via the power amplifier 71.

In the example of Fig. 7C the sensing portion is provided within the audio transducer 3. In this example separate terminals may be provided for the audio transducer 3 and the sensing portion 5. In the example of Fig. 7C the electrical output signal 13 bypasses the power amplifier 71.

Whether the apparatus 1 is configured so that the electrical output signal 13 bypasses the power amplifier 71 or not may depend on a number of factors. For example, it may depend on the location of the sensing portion 5 within the audio transducer 3, the type of power amplifier 71 used and the level of interference with other components within an electronic device 61 or any other relevant factors.

Fig. 8 schematically illustrates example electronic circuitry 7 that may be used in some examples of the disclosure. In the example of Fig. 8 the sensing portion 5 is configured to detect the temperature of the audio transducer 3. It is to be appreciated that the sensing portion 5 could be configured to detect other parameters or operating conditions in other examples.

The example electronic circuitry 7 is configured to receive an audio input signal 73 and output a processed audio signal 75. In the example of Fig. 8 the electronic circuitry 7 comprises a temperature module 81 and a displacement module 83.

The temperature module 81 comprises means for processing the audio input signal 73 so as to control the temperature of the audio transducer 3 or components within the audio transducer 3. The temperature module 81 is configured to obtain an electrical output signal 13 from the sensing portion 5. The electrical output signal 13 comprises information about the current temperature of the audio transducer 3. This information can be used by a temperature limiter 85 within the temperature module to limit further temperature increases which could be generated while the audio transducers 3 provides the sound output signal 17.

The temperature limiter 85 may attenuate the audio input signal 73 in dependence on the current temperature as indicated by the electrical output signal 13. In some examples the temperature limiter 85 may provide indications to the electronic circuitry 7 so that signal processing algorithms such as equalisation, dynamic range controller, gain controller or other suitable processing algorithms can be adjusted. In the example of Fig. 8 there is no need for the temperature module 81 to estimate the temperature of the audio transducer 3 as this information can be obtained from the sensing portion 5.

The displacement module 83 comprises means for processing the audio input signal 73 so as to control the displacements of components within the audio transducer 3. The displacement module 83 comprises a displacement predictor 87 which is configured to predict the displacement of components within the audio transducer 3. The displacement module 83 also comprises a displacement limiter 89 which uses the predicted displacement to limit further displacement which could be generated while the audio transducers 3 provides the sound output signal 17.

Fig. 9 illustrates an example method. The method may be implemented using apparatus 1 as described above. In some examples the blocks of the method may be performed by the electronic circuitry 7 of the apparatus 1.

The method comprises, at block 91, obtaining an audio input signal 73. The method also comprises, at block 93 obtaining an electrical output signal 13 from a sensing portion 5 where the sensing portion 5 comprises two dimensional material 9 and is positioned within an apparatus 1 comprising an audio transducer 3 so as to determine one or more operating conditions of the audio transducer 3 and provide an output signal indicative of the one or more operating conditions. At block 95 the method comprises, using the obtained electrical output signal 13 to process the audio input signal 73 so as to control the audio signal 15 provided to the audio transducer 3.

Fig. 10 schematically illustrates example electronic circuitry 7 that may be provided within the apparatus 1 in some examples of the disclosure.

The electronic circuitry 7 illustrated in Fig. 10 may comprise a chip or a chip-set. In some examples the electronic circuitry 7 may be provided within the main control circuitry of an electronic device 61.

The electronic circuitry 7 comprises control circuitry 103. The control circuitry 103 may provide means for controlling an electronic device 61 such as communications device. The control circuitry 103 may also provide means for performing the methods, or at least part of the methods, of examples of the disclosure.

The electronic circuitry 7 comprises processing circuitry 105 and memory circuitry 107. The processing circuitry 105 may be configured to read from and write to the memory circuitry 107. The processing circuitry 105 may comprise one or more processors. The processing circuitry 105 may also comprise an output interface via which data and/or commands are output by the processing circuitry 105 and an input interface via which data and/or commands are input to the processing circuitry 105.

The memory circuitry 107 may be configured to store a computer program 109 comprising computer program instructions (computer program code 111) that controls the operation of the apparatus 91 when loaded into processing circuitry 105. The computer program instructions, of the computer program 109, provide the logic and routines that enable the electronic circuitry 7 to perform the example methods described above. The processing circuitry 105 by reading the memory circuitry 107 is able to load and execute the computer program 109.

The computer program 109 may arrive at the electronic circuitry 7 via any suitable delivery mechanism. The delivery mechanism may be, for example, a non-transitory computer-readable storage medium, a computer program product, a memory device, a record medium such as a compact disc read-only memory (CD-ROM) or digital versatile disc (DVD), or an article of manufacture that tangibly embodies the computer program. The delivery mechanism may be a signal configured to reliably transfer the computer program 109. The apparatus may propagate or transmit the computer program 109 as a computer data signal. In some examples the computer program code 109 may be transmitted to the electronic circuitry 7 using a wireless protocol such as Bluetooth, Bluetooth Low Energy, Bluetooth Smart, 6LoWPan (IPv6 over low power personal area networks) ZigBee, ANT+, near field communication (NFC), Radio frequency identification, wireless local area network (wireless LAN) or any other suitable protocol.

Although the memory circuitry 107 is illustrated as a single component in the figures it is to be appreciated that it may be implemented as one or more separate components some or all of which may be integrated/removable and/or may provide permanent/semi-permanent/dynamic/cached storage.

Although the processing circuitry 105 is illustrated as a single component in the figures it is to be appreciated that it may be implemented as one or more separate components some or all of which may be integrated/removable.

References to “computer-readable storage medium”, “computer program product”, “tangibly embodied computer program” etc. or a “controller”, “computer”, “processor” etc. should be understood to encompass not only computers having different architectures such as single/multi-processor architectures, Reduced Instruction Set Computing (RISC) and sequential (Von Neumann)/parallel architectures but also specialized circuits such as field-programmable gate arrays (FPGA), applicationspecific integrated circuits (ASIC), signal processing devices and other processing circuitry. References to computer program, instructions, code etc. should be understood to encompass software for a programmable processor or firmware such as, for example, the programmable content of a hardware device whether instructions for a processor, or configuration settings for a fixed-function device, gate array or programmable logic device etc.

As used in this application, the term “circuitry” refers to all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s)/software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of “circuitry” applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term “circuitry” would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware. The term “circuitry” would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in a server, a cellular network device, or other network device.

Examples of the disclosure provide the advantage that they enable the current conditions of the audio transducer 3 to be used to control the audio signals 15 provided to an audio transducer. This may ensure that the audio signals 15 are provided at a level and for durations which will not cause overheating or other damage to the audio transducer 3.

In some examples the sensing portion 5 could be configured to detect parameters that are not directly related to the functioning of the audio transducer 3 and/or parameters which are related to the functioning of other components within an electronic device 61. For instance, in some examples the sensing portion 5 could be used to detect visible light or other types of electromagnetic radiation. This may be useful in examples where the apparatus 1 is provided within an imaging device. This may enable the light levels to be determined independently of the imaging device.

In some examples information indicative of the detected parameter may be provided to a user of the apparatus 1 and/or electronic device 61. For example, the sensing portion 5 could be configured to detect temperature and/or humidity or any other suitable parameter relating to the environment of the apparatus 1 and/or electronic device 61 that may be of interest to a user of the electronic device 61. In such examples an output signal 13 from the sensing portion 5 could be processed and provided to an output device to enable information indicative of the sensed parameter to be provided to a user. In other examples the output signal 13 from the sensing portion 5 could be provided to other components of the electronic device 61 and may be used by the other components to control the operation of other components of the electronic device 61. In such examples the sensing portion 5 may provide additional sensing capability within the electronic device 61 without increasing the number of components within the electronic device 61 because the sensing portion 5 is integrated with the audio transducer 3.

In this description the term coupled means operatively coupled. It is to be appreciated that there may comprise any number of components between coupled components including zero components.

The term “comprise” is used in this document with an inclusive not an exclusive meaning. That is any reference to X comprising Y indicates that X may comprise only one Y or may comprise more than one Y. If it is intended to use “comprise” with an exclusive meaning then it will be made clear in the context by referring to “comprising only one...” or by using “consisting”.

In this brief description, reference has been made to various examples. The description of features or functions in relation to an example indicates that those features or functions are present in that example. The use of the term “example” or “for example” or “may” in the text denotes, whether explicitly stated or not, that such features or functions are present in at least the described example, whether described as an example or not, and that they can be, but are not necessarily, present in some of or all other examples. Thus “example”, “for example” or “may” refers to a particular instance in a class of examples. A property of the instance can be a property of only that instance or a property of the class or a property of a subclass of the class that includes some but not all of the instances in the class. It is therefore implicitly disclosed that a feature described with reference to one example but not with reference to another example, can where possible be used in that other example but does not necessarily have to be used in that other example.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

l/we claim:

Claims

1. An apparatus comprising:

an audio transducer configured to transduce an audio signal into a sound output signal;

a sensing portion comprising two dimensional material wherein the sensing portion is positioned, at least partially, within the apparatus so as to enable one or more operating conditions of the audio transducer to be determined and provide an output signal based on the one or more operating conditions; and an output terminal configured to provide the output signal from the sensing portion to electronic circuitry so as to enable the electronic circuitry to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

2. The apparatus as claimed in any preceding claim wherein controlling the audio signal provided to the transducer comprises adjusting a driving voltage level of the transducer.

3. The apparatus as claimed in any preceding claim wherein the sensing portion is provided inside the audio transducer.

4. The apparatus as claimed in claim 3 wherein the sensing portion is configured inside the audio transducer to enable operating conditions of one or more parts of the audio transducer to be determined.

5. The apparatus as claimed in any preceding claim wherein the electronic circuitry is provided, at least partially, within the apparatus.

6. The apparatus as claimed in any preceding claim wherein the audio transducer comprises a voice coil and the two dimensional material is coupled the voice coil.

7. The apparatus as claimed in any preceding claim wherein the audio transducer comprises a diaphragm and the two dimensional material is coupled to the diaphragm.

8. The apparatus as claimed in any preceding claim wherein the audio transducer comprises a magnet and the two dimensional material is coupled to the magnet.

9. The apparatus as claimed in any preceding claim wherein the audio transducer comprises a bottom plate and the two dimensional material is coupled to the bottom plate.

10. The apparatus as claimed in any preceding claim wherein the sensing portion is positioned within the apparatus to provide a heat sink for the audio transducer.

11. The apparatus as claimed in any preceding claim wherein the two dimensional material comprises a conductive material.

12. The apparatus as claimed in any preceding claim wherein the two dimensional material comprises at least one of: graphene, graphene oxide, reduced graphene oxide, functionalized graphene, molybdenum disulphide, tungsten disulphide, boron nitride.

13. The apparatus as claimed in any preceding claim wherein the output signal of the sensing portion provides an indication of a change in conductivity of the two dimensional material in response to operating conditions of the audio transducer.

14. The apparatus as claimed in any preceding claim wherein the operating conditions of the audio transducer comprises at least one of; temperature, humidity, light, analytes.

15. The apparatus as claimed in any preceding claim wherein the electronic circuitry is configured to process an audio input signal and the output signal from the sensing portion so as to provide a modified audio signal to the audio transducer.

16. An electronic device comprising an apparatus as claimed in any preceding claims and electronic circuitry.

17. A method comprising:

obtaining an audio input signal;

obtaining an electrical output signal from a sensing portion where the sensing portion comprises two dimensional material and is positioned within an apparatus comprising an audio transducer so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the determined one or more operating conditions; and processing the audio input signal so as to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.

16. A computer program comprising computer program instructions that, when executed by processing circuitry, cause obtaining an audio input signal;

17. An audio transducer comprising;

a first terminal configured to receive an audio signal to enable the audio transducer to transduce the audio signal into a sound output signal;

a sensing portion comprising two dimensional material wherein the sensing portion is positioned within the apparatus so as to determine one or more operating conditions of the audio transducer to be determined and provide an output signal based on the one or more operating conditions; and a second terminal configured to provide the output signal from the sensing portion.

18. The audio transducer as claimed in claim 17 wherein the second terminal is configured to enable the output signal from the sensing portion to be provided to electronic circuitry to enable the electronic circuitry to control the audio signal provided to the audio transducer based on the output signal from the sensing portion.