Provided is an electronic device for controlling surface heart and a method of controlling the electronic device. The electronic device includes a speaker, a temperature sensor, a memory, and a processor electrically coupled to the speaker, the temperature sensor, and the memory. The processor obtains first temperature information based on impedance information measured in a coil included in the speaker; obtains second temperature information measured by the temperature sensor, the second temperature information based on a heat source disposed adjacent to the speaker; predicts a surface temperature of a surface area of the electronic device, opposite to an internal area in which the speaker is disposed, based on the first temperature information and the second temperature information using a nonlinear approximation function; and controls an audio signal input to the speaker based on the predicted surface temperature.

Voice coil actuators and loudspeakers containing same. The voice coil actuators include moving voice coil assemblies that have multiple segments. Each segment of a moving voice coil assembly is separately controlled by an amplifier, one channel of an amplifier, and combinations thereof utilized in combination with a position sensor that senses the position of the moving voice coil assembly. By this arrangement, the voice coil actuators produce a linear force per unit current throughout the range of motion while obtaining the benefits and advantages associated with both over-hung and under-hung voice coil actuator designs.

A loudspeaker controller for estimating a fundamental resonance frequency of a loudspeaker includes: an amplifier circuit, arranged to generate a driving signal of the loudspeaker according to an audio input signal; a sensing circuit, arranged to sense characteristics of the driving signal to generate a measurement signal; a plurality of band pass filter circuits, arranged to filter the measurement signal to generate a plurality of filter outputs, respectively, wherein the plurality of band pass filter circuits have different passbands; and an estimation circuit, arranged to estimate the fundamental resonance frequency according to the plurality of filter outputs.

A sound emitting device includes a speaker box, a loudspeaker, a temperature sensor, a central processing unit and a signal amplifier. The speaker box includes a sound hole. The temperature sensor detects a temperature of the sound emitting device and generates a detection signal. The central processing unit pre-stores a default audio signal. When the central processing unit determines that the loudspeaker is in a standby state and the temperature of the sound emitting device exceeds a threshold value, the central processing unit issues the default audio signal. The signal amplifier is connected to and disposed between the central processing unit and the loudspeaker for amplifying the default audio signal and transmitting the amplified default audio signal to the loudspeaker. A vibration diaphragm of the loudspeaker undergoes a vibration action according to the amplified default audio signal.

A speaker includes a housing including a front housing provided in a conductive material; a driver including a diaphragm; a magnetic circuit including a permanent magnet; and an electric circuit including a voice coil to which current is applied based on an input electrical signal, and a first electric circuit configured to vibrate the driver based on the voice coil and a magnetic field formed by the magnetic circuit; wherein the diaphragm include a coating that is surface-coated with a conductive material so as to have a capacitance with the front housing.

A panel audio loudspeaker includes a panel and an actuator attached to a surface of the panel and configured to cause vibration of the panel. The actuator comprises a magnetic coil in thermal communication with the panel. The panel audio loudspeaker further comprises a plurality of electrical sensors electrically coupled to the magnetic coil and configured to output time-varying electrical data for the magnetic coil, and an electronic control module in communication with the magnetic coil and the electrical sensors. The electronic control module is configured to perform operations comprising: providing a current to the magnetic coil; receiving the time-varying electrical data for the magnetic coil; determining an electrical energy provided to the magnetic coil between a first time and a second time; accessing a thermal model of the panel; and determining a change in a panel temperature between the first time and the second time.

A system for determining the temperature of a voice coil of a speaker includes a first pre-emphasis filter which has an input coupled to receive a digitized current sense signal. The first pre-emphasis filter applies a gain to signal components at a selected frequency band and provides a pre-emphasized current sense signal. The system includes a second pre-emphasis filter which has an input coupled to receive a digitized voltage sense signal. The second pre-emphasis filter applies a gain to the signal components at the selected frequency band and provides a pre-emphasized voltage sense signal. The system includes a first quantizer module configured to map the pre-emphasized signal to a quantized current sense signal, and includes a second quantizer module configured to map the pre-emphasized voltage sense signal to a quantized voltage sense signal.

A system may include a first input configured to receive a playback signal to be played back to a transducer, a second input configured to receive temperature information associated with the transducer, and a thermal-controlled gain element configured to determine a sub-band gain to be applied to a selected frequency band of the playback signal, wherein the thermal-controlled gain element determines the gain based on the temperature information and apply the sub-band gain to the selected frequency band.

The invention provides a loudspeaker nonlinear compensation method. The method includes steps: obtaining system parameter of the loudspeaker, the No. i time-domain excitation voltage signal and the No. i state vector of the loudspeaker; compensating the No. i time-domain excitation voltage signal according to the system parameter and the No. i state vector and obtain i compensation voltage signal; obtaining the No. i+1 state vector according to the calculation of the system parameter and the No. i compensation voltage signal; outputting the No. i compensation voltage signal and record the quantity of the compensation voltage signal; judging whether the quantity of the compensation voltage signal is equal to the preset number value.

An identification method of nonlinear system of loudspeaker includes the following steps: providing an amplified pumping signal to the loudspeaker; measuring a voltage signal and a current signal; obtaining linear parameters of the loudspeaker system; obtaining the nonlinear parameters of the loudspeaker system: inputting the measured current signal into a lumped parameter model of the loudspeaker system to calculate the estimated voltage signal; comparing the estimated voltage signal with the measured voltage signal to calculate a voltage error signal between the two; conducting decoherence with the voltage error signal to get rid of a linear component of the voltage error signal, obtaining then, according to the voltage error signal after decoherence, the nonlinear parameters by using an adaptive iterative algorithm.