Abstract: A demodulation signal generator, coupled to an air-pulse generator comprising a flap pair, includes a resonance circuit. The resonance circuit produces a first demodulation signal and a second demodulation signal. The resonance circuit and the flap pair co-perform a resonance operation, such that the first demodulation signal and the second demodulation signal are generated via the co-performed resonance operation and have opposite polarity. The flap pair performs a differential movement to form an opening to perform a demodulation operation on a modulated air pressure variation.

Abstract: A venting device includes a first flap, which is configured to be actuated to swing upward during a rising time, and a second flap, which is disposed opposite to the first flap and configured to be actuated to swing downward during a falling time, a first actuating portion disposed on the first flap, and a second actuating portion disposed on the second flap. The venting device configured to form a vent is disposed within a wearable sound device or to be disposed within the wearable sound device. The vent is formed via applying a first voltage to the first actuating portion and applying a second voltage on the second actuating portion, such that the venting device gradually forms the vent.

Abstract: An air-pulse generating device includes a film structure including a flap pair. The film structure is actuated to perform a common mode movement, so as to form an amplitude-modulated ultrasonic air pressure variation with an ultrasonic carrier frequency. The film structure is actuated to perform a differential mode movement, so as to form an opening at a rate synchronous with the ultrasonic carrier frequency. The air-pulse generating device produces a plurality of air pulses according to the amplitude-modulated ultrasonic air pressure variation.

Abstract: A cell includes a membrane and an actuating layer. The membrane includes a first membrane subpart and a second membrane subpart, wherein the first membrane subpart and the second membrane subpart are opposite to each other. The actuating layer is disposed on the first membrane subpart and the second membrane subpart. The first membrane subpart includes a first anchored edge which is fully or partially anchored, and edges of the first membrane subpart other than the first anchored edge are non-anchored. The second membrane subpart includes a second anchored edge which is fully or partially anchored, and edges of the second membrane subpart other than the second anchored edge are non-anchored.

Abstract: A speaker system includes a first acoustic transducer, a second acoustic transducer and a spreading structure. The first acoustic transducer is configured to generate a first acoustic wave. The second acoustic transducer is configured to generate a second acoustic wave. The spreading structure is disposed over the first acoustic transducer and configured to guide the first acoustic wave to propagate through a sound passage formed within the spreading structure. A directionality of the first acoustic wave is spread at a sound outlet of the spreading structure after the first acoustic wave propagates through the sound passage in the spreading structure.

Abstract: The present invention discloses a feedback control system. The feedback control system comprises a plant, configured to produce an output according to a control signal; a first summing block, configured to produce a first difference between an input signal and a measured output signal; a first controller, configured to generate the control signal, such that the first difference decreases to be less than a first threshold or is less than the first threshold; wherein the first controller comprises a memory configured to store a table, and the table contains information of a plurality of transfer functions corresponding to a plurality of operating conditions; wherein the first controller determines an operating condition under which the plant operates, and chooses to utilize a transfer function corresponding to the operating condition to generate the control signal according to the transfer function and the first difference.

Abstract: A package structure includes a first substrate and a first device disposed on the first substrate. The first device includes at least one anchor structure, a film structure anchored by the anchor structure and an actuator configured to control the film structure to form a first vent temporarily. The film structure partitions a space into a first volume to be connected to an ear canal and a second volume connected to an ambient of a wearable sound device. The ear canal and the ambient are connected via the first vent when the first vent is opened. The first vent is opened by controlling a first membrane portion and a second membrane portion of the film structure, such that a difference between a first displacement of the first membrane portion and a second displacement of the second membrane portion is larger than a thickness of the film structure.

Abstract: A sound producing cell includes a membrane and an actuating layer. The membrane includes a first membrane subpart and a second membrane subpart, wherein the first membrane subpart and the second membrane subpart are opposite to each other. The actuating layer is disposed on the first membrane subpart and the second membrane subpart. The first membrane subpart includes a first anchored edge which is fully or partially anchored, and edges of the first membrane subpart other than the first anchored edge are non-anchored. The second membrane subpart includes a second anchored edge which is fully or partially anchored, and edges of the second membrane subpart other than the second anchored edge are non-anchored.

Abstract: A package structure includes a cover and a cell disposed within the cover. The cell includes a membrane, an actuating layer and an anchor structure. The membrane includes a first membrane subpart and a second membrane subpart, wherein the first membrane subpart and the second membrane subpart are opposite to each other in a top view. The actuating layer is disposed on the first membrane subpart and the second membrane subpart in the top-view direction. The membrane is anchored by the anchor structure. The first membrane subpart includes a first anchored edge which is fully or partially anchored, and edges of the first membrane subpart other than the first anchored edge are non-anchored. The second membrane subpart includes a second anchored edge which is fully or partially anchored, and edges of the second membrane subpart other than the second anchored edge are non-anchored.

Abstract: A driving circuit, configured to drive a venting device, includes a first node, a second node, and an amplifying circuit. The venting device, configured to be controlled to open a vent or seal the vent, includes a film structure, which includes a first flap and a second flap, and an actuator, which includes a first actuating portion disposed on the first flap and a second actuating portion disposed on the second flap. When the venting device is controlled to open the vent, the driving circuit generates a first voltage at the first node and generates a second voltage at the second node. When the venting device is controlled to seal the vent, the driving circuit generates a third voltage at both the first node and the second node. The first voltage is larger than the third voltage, and the third voltage is larger than the second voltage.

Abstract: A method is applied in a controller within a driving circuit comprising a driving sub-circuit configured to drive a load. The method comprises steps of: performing a table learning operation on a table at least at a first rate during a learning period; and performing the table learning operation on the table at a second rate lower than the first rate after the learning period; wherein the table is stored in a memory within the controller. The table learning operation comprises steps of: receiving a first feedback signal from the load corresponding to a first cycle; obtaining a control code from the table according to the first feedback signal; generating a control signal according to the control code; receiving a second feedback signal from the load corresponding to the second cycle; and updating the control code and saving the updated control code back to the table in the memory.

Abstract: A method is applied in a controller within a driving circuit comprising a driving sub-circuit configured to drive a load. The method comprises steps of: performing a table learning operation on a table at least at a first rate during a learning period; and performing the table learning operation on the table at a second rate lower than the first rate after the learning period; wherein the table is stored in a memory within the controller. The table learning operation comprises steps of: receiving a first feedback signal from the load corresponding to a first cycle; obtaining a control code from the table according to the first feedback signal; generating a control signal according to the control code; receiving a second feedback signal from the load corresponding to the second cycle; and updating the control code and saving the updated control code back to the table in the memory.

Abstract: A sound producing package structure includes a shell and a chip. The shell includes a top structure, a bottom structure and a sidewall structure. The chip is disposed inside the shell and configured to produce an acoustic wave, wherein the chip includes a thin film structure and an actuator configured to actuate the thin film structure, and the thin film structure is substantially parallel to the top structure and the bottom structure. A first opening is formed on the sidewall structure, and the acoustic wave propagates outwards through the first opening.

Abstract: A method, which is applied in a driving circuit including an analog-to-digital convertor (ADC) and a switching circuit including an inductor and coupled to a load, includes steps of: performing an analog-to-digital conversion on a load voltage of the load at a first rate; and producing at least a current pulse flowing through the inductor at a second rate. Wherein, each current pulse among the at least a current pulse is accomplished within a second cycle corresponding to the second rate, all of the at least a current pulse are accomplished within a first cycle corresponding to the first rate, and a first length of the first cycle is longer than twice of a second length of the second cycle.

Abstract: An acoustic impedance measuring system configured to measure an acoustic impedance of an acoustic component includes a first chamber, a second chamber, a first sound pressure sensing device, a second sound pressure sensing device and a sound source. The first sound pressure sensing device is configured to sense a sound pressure in the first chamber. The second sound pressure sensing device is configured to sense a sound pressure in the second chamber. The sound source is connected to the first chamber, wherein the sound source generates a sound propagating towards a first cavity inside the first chamber. The acoustic component is disposed between the first chamber and the second chamber for being measured the acoustic impedance of the acoustic component, and the acoustic impedance of the acoustic component is measured by the first sound pressure sensing device and the second sound pressure sensing device.

Abstract: An air-pulse generating device includes a film structure. The film structure is driven by a modulation-driving signal, so as to form an amplitude-modulated ultrasonic air pressure variation with an ultrasonic carrier frequency. The film structure is driven by a first demodulation-driving signal and a second demodulation-driving signal, so as to form an opening at a rate synchronous with the ultrasonic carrier frequency. The air-pulse generating device produces a plurality of air pulses according to the amplitude-modulated ultrasonic air pressure variation.

Abstract: An air-pulse generating device includes a film structure including a flap pair. The film structure is actuated to perform a common mode movement, so as to form an amplitude-modulated ultrasonic air pressure variation with an ultrasonic carrier frequency. The film structure is actuated to perform a differential mode movement, so as to form an opening at a rate synchronous with the ultrasonic carrier frequency. The air-pulse generating device produces a plurality of air pulses according to the amplitude-modulated ultrasonic air pressure variation.

Abstract: A feedback control system configured to drive a load is disclosed. The feedback control system includes an up-sampling circuit, configured to perform an un-sampling operation on a source signal and produce an up-sampled signal with an up-sampling frequency according to the up-sampled signal and a feedback signal from the load; a delta circuit, coupled to the up-sampling circuit and configured to produce a delta signal; a sigma circuit, configured to produce a density modulation signal according to the delta signal; and a driving device, configured to drive the load according to the density modulation signal with the up-sampling frequency.

Abstract: An air-pulse generating device includes a film structure. The film structure is actuated such that the air-pulse generating device produces a plurality of air pulses. A horn-shaped outlet is formed within the air-pulse generating device, and the plurality of air pulses is propagated via the horn-shaped outlet.

Abstract: The present invention discloses a feedback control system. The feedback control system comprises a plant, configured to produce an output according to a control signal; a first summing block, configured to produce a first difference between an input signal and a measured output signal; a first controller, configured to generate the control signal, such that the first difference decreases to be less than a first threshold or is less than the first threshold; wherein the first controller comprises a memory configured to store a table, and the table contains information of a plurality of transfer functions corresponding to a plurality of operating conditions; wherein the first controller determines an operating condition under which the plant operates, and chooses to utilize a transfer function corresponding to the operating condition to generate the control signal according to the transfer function and the first difference.