CN102651836A - Audio Drivers for Flat Electroacoustic Actuators - Google Patents

Abstract

The invention discloses an audio driver for a flat-plate type electroacoustic actuator, which is coupled with a capacitive flat-plate type electroacoustic actuating device, wherein the flat-plate type electroacoustic actuating device comprises a perforated electrode plate and a charged diaphragm plate, and the audio driver comprises: a power signal amplifier and an audio signal amplifying transformer for receiving an input audio signal and converting the input audio signal into two high-voltage output audio signals; two high-voltage output audio signals are respectively coupled with the perforated electrode plate and the charged diaphragm plate; wherein, the audio amplifying transformer and the flat-plate type electro-acoustic actuating device effectively form a low-pass filter. The invention can effectively reduce the volume and the weight of the electroacoustic actuator system, and save the power consumption of the electroacoustic actuator to prolong the service time of the portable electronic product.

Description

Audio Drivers for Flat Electroacoustic Actuators

technical field

The present invention relates to an audio driver, in particular to an audio driver used for a flat electroacoustic actuator.

Background technique

With the advancement of technology, portable electronic products are becoming thinner and thinner, and the power consumption requirements of electronic products are the most important. For traditional portable electronic products with built-in electroacoustic actuators, in addition to the large volume and weight of the flat electroacoustic actuator system, the power consumption of the required driving device is about 1.5-2W, accounting for 100% of the total power consumption of portable electronic products. 20%-70% of the overall power consumption is too high for portable electronic products. Therefore, the flat-panel electroacoustic actuator system has gradually received attention.

FIG. 1 is a schematic diagram of the circuit structure of an audio driver 102 used in a flat electroacoustic actuator 101 . The audio driver 102 is coupled to the capacitive flat electroacoustic actuator 101 . The audio driver 102 includes an audio amplifier 108 and a low-bandwidth-high-power transformer 109 for receiving an input audio signal Sin and converting it into two positive and negative high voltage output audio signals So1 and So2 of equal strength. The flat-plate electroacoustic actuator 101 includes two electrodes 106 and 104 and a very flat and thin film strip 105 between the electrodes 106 and 104. The electrodes 106 and 104 can be pole plate grids (grid) or stators (stator). The very flat thin film strip 105 receives high voltage direct current 107 . When two positive and negative high-voltage output audio signals So1 and So2 of equal strength are applied to the electrodes 106 and 104, the very flat and thin film strip 105 will be attracted or repelled by the electrodes 106 and 104, thereby vibrating and producing sound.

Since the known flat-type electroacoustic actuator system uses a high-voltage signal to generate sound, a low-frequency wide-high power transformer 109 must be used in the audio driver 102 to convert the signal generated by the audio amplifier 108 into a flat-type electroacoustic actuator. Two positive and negative high-voltage output audio signals So1 and So2 of equal strength required by the actuator 101. However, the low-bandwidth-high-power transformer 109 requires a large coil inductor, a large-sized iron core and takes up a large space in order to avoid distortion in the entire audio frequency range, and is also an expensive component. In other words, it will result in that the volume and weight of the flat electroacoustic actuator 101 cannot be effectively reduced.

Therefore, how to effectively reduce the volume and weight of the electro-acoustic actuator system, and save the power consumption of the electro-acoustic actuator to increase the use time of portable electronic products is one of the important issues in this design field.

Contents of the invention

In view of the deficiencies of the audio driver technology of the above-mentioned flat electroacoustic actuator system, the present invention provides an audio driver to effectively reduce the volume and weight of the electroacoustic actuator system and save the power of the electroacoustic actuator. Consumed to improve the use time of portable electronic products.

The invention provides an audio driver for a flat electroacoustic actuator, the flat electroacoustic actuator includes a perforated electrode plate and a charged diaphragm plate, the audio driver is coupled to the flat electroacoustic actuator , wherein the audio driver includes: a power signal amplifier for receiving an input audio signal and converting it into an input audio power amplified signal; and an audio amplification transformer for receiving the input audio power amplified signal and amplifying the input audio power signal Converted into two high-voltage output audio signals, the two high-voltage output audio signals are respectively coupled to the perforated electrode plate and the charged diaphragm plate; wherein, the audio amplification transformer and the flat electroacoustic actuator effectively form a low pass filter.

The present invention also provides an audio driver for a flat electroacoustic actuator, the flat electroacoustic actuator includes a perforated electrode plate and a charged diaphragm plate, the audio driver is coupled to the flat electroacoustic actuator device, wherein the audio driver includes: a power signal amplifier; used to receive an input audio signal and convert it into an input audio power amplified signal; and an audio amplifier transformer, used to accept the input audio power amplified signal and amplify the input audio power The signal is converted into a high-voltage output audio signal, the high-voltage output audio signal is coupled to the perforated electrode plate, and the charged diaphragm plate is coupled to the ground; wherein, the audio amplification transformer and the flat-plate electroacoustic actuator effectively form a low pass filter.

Preferably, the audio driver further includes: an AC-DC power converter or a DC-DC power converter for providing high voltage DC to the power signal amplifier.

Preferably, the power signal amplifier is a class AB amplifier or a class D amplifier.

Preferably, the input audio signal is provided by an MP3 player, a CD player or a smart phone.

Preferably, the charged diaphragm plate includes a film main body layer and an electrode layer with charges.

Compared with the prior art, the audio driver for the flat electroacoustic actuator provided by the present invention can not only receive the input audio signal and convert it into a high-voltage output audio signal, but also be compatible with the capacitive electroacoustic actuator. effectively forms a low-pass filter. Therefore, the present invention can not only effectively reduce the volume and weight of the electro-acoustic actuator system, but also further save the power consumption of the electro-acoustic actuator to increase the use time of portable electronic products.

The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, so as to make the characteristics and advantages of the present invention more obvious.

Description of drawings

Figure 1 shows a schematic diagram of the circuit structure of an existing audio driver for a flat-panel electroacoustic actuator;

FIG. 2 is a schematic diagram of the circuit structure of an audio driver for a flat electroacoustic actuator according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of the circuit structure of an audio driver for a flat electroacoustic actuator according to another embodiment of the present invention.

Detailed ways

A detailed description will be given below of embodiments of the present invention. While the invention will be described in conjunction with examples, it will be understood that it is not intended to limit the invention to these examples. On the contrary, the invention is intended to cover various changes, modifications and equivalents as defined within the spirit and scope of the invention as defined by the appended claims.

FIG. 2 is a schematic diagram of the circuit structure of an audio driver 202 used in a flat electroacoustic actuator 201 according to an embodiment of the present invention. The audio driver 202 is coupled to the capacitive flat electroacoustic actuator 201 . The audio driver 202 includes a power signal amplifier 204 and an audio amplifying transformer 203 for receiving an input audio signal Sin and converting it into two positive and negative high voltage output audio signals So1 and So2 of equal strength. In one embodiment, the input audio signal Sin is an audio signal provided by a portable multimedia device such as an MP3 player, a CD player, or a smart phone. The power signal amplifier 204 receives the high-voltage DC VDCH provided by the high-voltage DC source 209, and amplifies the input audio signal Sin into an input audio power amplified signal Sin'. In one embodiment, the high voltage DC source 209 is provided by an AC-DC power converter (not shown in the figure) or a DC-DC power converter (not shown in the figure). The power signal amplifier 204 is a class AB amplifier or a class D amplifier, but not limited thereto.

The capacitive flat electroacoustic actuator 201 includes a perforated electrode plate 205 and a charged diaphragm plate 210 , wherein the perforated electrode plate 205 has a plurality of openings 207 . The charged diaphragm plate 210 includes a film body layer 208 and an electrode layer 206 with charges. In one embodiment, the main film layer 208 may be made of polytetrafluoroethylene (PTFE) or fluorinated ethylene propylene (FEP), but not limited thereto. In one embodiment, the electrode layer 206 is made of aluminum, chromium or other conductive materials, but not limited thereto. The perforated electrode plate 205 and the charged diaphragm plate 210 receive high-voltage output audio signals So1 and So2 respectively.

The capacitive flat-plate electroacoustic actuator 201 can be regarded as a capacitor, and its capacitance C can be expressed according to the following formula:

$\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}{\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}\frac{\mathrm{<span\; class="notranslate">\; A</span>}}{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, ε _o is the permittivity of vacuum, and ε _r is the relative permittivity, A represents the area of the charged diaphragm plate 210 and the perforated electrode plate 205, and d represents the distance between the charged diaphragm plate 210 and the perforated electrode plate 205.

The input audio power amplification signal Sin′ is amplified by N ₂ /N ₁ times by the audio amplification transformer 203 , and converted into output audio signals So1 and So2 to drive the capacitive flat electroacoustic actuator 201 . in

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; ,</span>$ ${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

or

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; ,</span>$ ${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

In one embodiment, the ratio N ₂ /N ₁ of the number of coils between the secondary side and the primary side of the audio amplification transformer 203 is 50-120. In another embodiment, the coil on the secondary side or the primary side is an enameled wire of 0.12φ-0.02φ.

The power consumption W _C of the capacitive flat electroacoustic actuator 201 can be expressed according to the following formula:

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; C</span>}{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

Although the potential difference (S _o1 -S _o2 ) ² is large, the capacitance C of the capacitive flat electroacoustic actuator 201 is extremely small (usually between 20pF-20nF). Therefore, the power consumption W _C of the capacitive flat-plate electroacoustic actuator 201 is on the order of μW.

Advantageously, the audio amplification transformer 203 not only amplifies the input audio power amplification signal Sin' by N ₂ /N ₁ times, but also effectively forms a low-pass filter with the capacitive electroacoustic actuator to filter the output to The high-frequency signal components of the audio signals So1 and So2 are output. In addition, the audio amplification transformer 203 is modulated within the broadband of a higher frequency input audio signal Sin, so it is not necessary to use a transformer with low frequency broadband and high power, but only needs to use a transformer with a higher center frequency and lower cost, further The volume and weight of the electroacoustic actuator system are effectively reduced, and the power consumption of the electroacoustic actuator is also saved to increase the use time of portable electronic products. In one embodiment, the silicon steel sheet of the audio amplifier transformer 203 has low frequency, directivity and high magnetic conductivity. In another embodiment, the bobbin of the audio amplifying transformer 203 is made of LCP material and the pin is C-shaped, so as to prevent the wire diameter of the coil on the secondary side or the primary side from being broken due to too small diameter.

FIG. 3 is a schematic diagram showing the circuit structure of an audio driver for a flat electroacoustic actuator according to another embodiment of the present invention. The audio driver 202 is coupled to the capacitive flat electroacoustic actuator 201 . The audio driver 202 includes a power signal amplifier 204 and an audio amplifying transformer 203 for receiving an input audio signal Sin and converting it into two positive and negative high voltage output audio signals So1 and So2 of equal strength. In one embodiment, the input audio signal Sin is an audio signal provided by a portable multimedia device such as an MP3 player, a CD player, or a smart phone. The power signal amplifier 204 receives the high-voltage DC VDCH provided by the high-voltage DC source 209, and amplifies the input audio signal Sin into an input audio power amplified signal Sin'. In one embodiment, the high voltage DC source 209 is provided by an AC-DC power converter (not shown in the figure) or a DC-DC power converter (not shown in the figure). The power signal amplifier 204 is a class AB amplifier or a class D amplifier, but not limited thereto.

The capacitive flat electroacoustic actuator 201 includes a perforated electrode plate 205 and a charged diaphragm plate 210 , wherein the perforated electrode plate 205 has a plurality of openings 207 . The charged diaphragm plate 210 includes a film body layer 208 and an electrode layer 206 with charges. In one embodiment, the main film layer 208 may be made of polytetrafluoroethylene (PTFE) or fluorinated ethylene propylene (FEP), but not limited thereto. In one embodiment, the electrode layer 206 is made of aluminum, chromium or other conductive materials, but not limited thereto. The perforated electrode plate 205 receives the high voltage output audio signal So1. One end of the charged diaphragm plate 210 is grounded.

The input audio power amplification signal Sin′ is amplified by N ₂ /N ₁ times by the audio amplification transformer 203 , and converted into output audio signals So1 and So2 to drive the capacitive flat electroacoustic actuator 201 . in,

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

or

${\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}}^{<span\; class="notranslate">\; \&prime;</span>}\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; DCH</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

The power consumption W _C of the capacitive flat electroacoustic actuator 201 can be expressed according to the following formula:

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}{{\mathrm{<span\; class="notranslate">\; CS</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

In one embodiment, the ratio N ₂ /N ₁ of the number of coils between the secondary side and the primary side of the audio amplification transformer 203 is 50-120. In another embodiment, the coil on the secondary side or the primary side is an enameled wire of 0.12φ-0.02φ.

Although S _o1 ² is large, the capacitance C of the capacitive flat electroacoustic actuator 201 is extremely small (usually between 20pF-20nF). Therefore, the power consumption W _C of the capacitive flat-plate electroacoustic actuator 201 is on the order of μW.

Advantageously, the audio amplification transformer 203 not only amplifies the input audio power amplification signal Sin' by N ₂ /N ₁ times, but also effectively forms a low-pass filter with the capacitive electroacoustic actuator to filter the output to The high-frequency signal component of the audio signal So1 is output. In addition, the audio amplification transformer 203 is modulated within the broadband of a higher frequency input audio signal Sin, so it is not necessary to use a transformer with low frequency broadband and high power, but only needs to use a transformer with a higher center frequency and lower cost, further The volume and weight of the electroacoustic actuator system are effectively reduced, and the power consumption of the electroacoustic actuator is also saved to increase the use time of portable electronic products. In one embodiment, the silicon steel sheet of the audio amplifier transformer 203 has low frequency, directivity and high magnetic conductivity. In another embodiment, the bobbin of the audio amplifying transformer 203 is made of LCP material and the pin is C-shaped, so as to prevent the wire diameter of the coil on the secondary side or the primary side from being broken due to too small diameter.

The above detailed description and drawings are only typical embodiments of the present invention. Obviously, various additions, modifications and substitutions are possible without departing from the spirit and scope of the present invention defined by the appended claims. Those skilled in the art should understand that the present invention can be changed in form, structure, layout, proportion, material, elements, components and other aspects in actual application according to the specific environment and work requirements without departing from the principle of the invention. Accordingly, the embodiments disclosed herein are intended to be illustrative and not limiting, with the scope of the invention being defined by the scope of the appended claims and their legal equivalents, rather than by the foregoing description.

The terms and expressions used herein are terms of description rather than limitation, and when using these terms and expressions, it is not intended to exclude other equivalents of the features (or parts of the features) disclosed and described herein, and should It is realized that various modifications of the invention are possible within the appended claims. There may also be some other modifications, changes and substitutions in the present invention. The claims are intended to cover all such equivalents.

Claims (10)

1. An audio driver for a flat-plate type electro-acoustic actuator, the flat-plate type electro-acoustic actuator comprising a perforated electrode plate and a charged diaphragm plate, the audio driver being coupled to the flat-plate type electro-acoustic actuator, wherein the audio driver comprises:

a power signal amplifier for receiving an input audio signal and converting the input audio signal into an input audio power amplified signal; and

the audio amplifying transformer is used for receiving the input audio power amplifying signal and converting the input audio power amplifying signal into two high-voltage output audio signals, and the two high-voltage output audio signals are respectively coupled with the perforated electrode plate and the charged vibrating diaphragm plate;

wherein, the audio amplifying transformer and the flat-plate type electro-acoustic actuating device effectively form a low-pass filter.

2. The audio driver for a flat-panel electroacoustic actuator of claim 1, further comprising: an AC-DC power converter or a DC-DC power converter for providing high voltage DC to the power amplifier.

3. The audio driver of claim 1, wherein the power amplifier is a class AB amplifier or a class D amplifier.

4. The audio driver for a flat panel electroacoustic actuator of claim 1, wherein the input audio signal is provided by an MP3 player, a CD player, or a smart phone.

5. The audio driver for a flat panel electroacoustic actuator of claim 1, wherein the charged diaphragm plate comprises a membrane body layer and an electrode layer with charges.

6. An audio driver for a flat-plate type electro-acoustic actuator, the flat-plate type electro-acoustic actuator comprising a perforated electrode plate and a charged diaphragm plate, the audio driver being coupled to the flat-plate type electro-acoustic actuator, wherein the audio driver comprises:

a power signal amplifier; for receiving an input audio signal and converting the input audio signal into an input audio power amplifying signal; and

the audio amplifying transformer is used for receiving the input audio power amplifying signal and converting the input audio power amplifying signal into a high-voltage output audio signal, the high-voltage output audio signal is coupled with the perforated electrode plate, and the charged vibrating membrane plate is coupled with the grounding end;

wherein, the audio amplifying transformer and the flat-plate type electro-acoustic actuating device effectively form a low-pass filter.

7. The audio driver for a flat-panel electroacoustic actuator of claim 6, further comprising: an AC-DC power converter or a DC-DC power converter for providing high voltage DC to the power amplifier.

8. The audio driver of claim 6, wherein the power amplifier is a class AB amplifier or a class D amplifier.

9. The audio driver for a flat panel electroacoustic actuator of claim 6, wherein the input audio signal is provided by an MP3 player, a CD player or a smart phone.

10. The audio driver for a flat panel electroacoustic actuator of claim 6, wherein the charged diaphragm plate comprises a membrane body layer and an electrode layer with charges.

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