Back to results
US 11,146,900 B2Granted
Inductive excursion sensing for audio transducers
AssigneeGoogle Inc.
InventorsMichael Asfaw, Chad Georges Seguin, David C. Breece, III, Leonardo Kusumo
Life of this patent
Estimating the term…
Abstract
Techniques, methods, systems, and other mechanisms for measuring the excursion of a speaker while being actively driven. Measuring excursion can involve attaching a flexible printed coil (FPC), including a sense coil, to the speaker, and monitoring an induced current as produced though the sense coil, and further detecting that violation of an excursion limit for the speaker may likely occur.
Claims18
A system comprising:
- an audio transducer configured to produce one or more electrical signals associated with generating sound waves from an audio signal, the audio transducer comprising:
- a magnet;
- a diaphragm;
- a flexible printed circuit (FPC) coupled to a surface of the diaphragm and having a first physical location within the audio transducer, wherein the FPC includes a sense coil;
- and
- a voice coil coupled to the diaphragm and having a second physical location within the audio transducer, wherein the voice coil is configured to generate an induced current signal through the sense coil that modifies the one or more electrical signals;
- and
- a signal analysis device that is configured to perform operations while driving the transducer to produce the one or more electrical signals, wherein the operations comprise:
- analyzing the one or more electrical signals from the audio transducer to monitor an electrical parameter of the induced current signal;
- measuring, based on the monitored electrical parameter, an excursion distance of the voice coil, wherein the excursion distance is associated with a distance between the second physical location of the voice coil and the first physical location of the FPC;
- determining, based on the measured excursion distance, whether the measured excursion distance exceeds a threshold distance;
- and
- performing an action to compensate for the measured excursion distance exceeding the threshold distance.
10 more elements
A system comprising:
- an audio transducer configured to produce one or more electrical signals associated with generating sound waves from an, the audio transducer comprising:
- a diaphragm;
- a magnet coupled to a metal enclosure;
- a flexible printed circuit (FPC) coupled to a surface of the metal enclosure and having a first physical location within the audio transducer, wherein the FPC includes a sense coil;
- and
- a voice coil coupled to the diaphragm and having a second physical location within the audio transducer and with respect to the first physical location of the FPC, wherein the voice coil is configured to generate an induced current signal through the sense coil that modifies the one or more electrical signals;
- and
- a signal analysis device that is configured to perform operations while driving the transducer to produce the one or more electrical signals, wherein the operations comprise:
- analyzing the one or more electrical signals from the audio transducer for to monitor an electrical parameter of the induced current signal;
- measuring, based on the monitored electrical parameter, an excursion distance of the voice coil, wherein the excursion distance is associated with a distance between the second physical location of the voice coil and the first physical location of the FPC;
- determining, based on the measured excursion distance, whether the measured excursion distance exceeds a threshold distance;
- and
- performing an action to compensate for the measured excursion distance exceeding the threshold distance.
10 more elements
A method, comprising:
- applying a high frequency signal to an audio signal received by an audio transducer to produce one or more electrical signals, where the one or more electrical signals are modified by an inductive current signal produced by a flexible printed circuit (FPC) wherein the FPC includes a sense coil;
- monitoring an amplitude of the inductive current signal, wherein the monitoring is performed by analyzing the one or more electrical signals from the transducer;
- and
- determining, based on the monitored amplitude, whether an active excursion distance associated with an element of the audio transducer has increased or decreased;
- and
- in response to determining that the active excursion distance has increased, determining whether the active excursion distance exceeds a threshold distance associated with an acceptable excursion range for the audio transducer;
- and
- performing an action to compensate for the active excursion distance exceeding the threshold distance.
5 more elements
An audio transducer for producing one or more electrical signals associated with generating sound waves from an audio signal, comprising:
- a magnet;
- a diaphragm;
- a flexible printed circuit (FPC) coupled to a surface of the diaphragm and having a first physical location within the audio transducer, wherein the FPC includes a sense coil;
- and
- a voice coil coupled to the diaphragm and having a second physical location within the audio transducer, wherein the voice coil is configured to generate an induced current signal through the FPC, and wherein the induced current has an amplitude usable to determine a distance between the first physical location of the FPC and the second physical location of the voice coil.
2 more elements
Dependencies are inferred from the claim text.