Thermal limiter for a panel speaker

An adaptive control circuit configurable in an electronic device having a surface, the electronic device including:

• a speaker, a temperature sensor configured to sense a temperature internal to the electronic device, the adaptive control circuit comprising:
• an audio input configured to receive an audio input signal responsive to an audio input power to the speaker;
• a temperature sense input configured to receive a temperature signal responsive to the sensed internal temperature;
• wherein responsive to the audio input signal and the temperature signal, a power control signal is computed by the adaptive control circuit so that a temperature of the surface of the electronic device at a later time approaches a previously determined target temperature;
• a thermal model dynamics module configured to input a value proportional to the audio input power to the speaker and predict therefrom a temperature of the surface of the electronic device after a sampling time interval of sensing the temperature;
• and
• an audio limiter configured to limit the audio input power to the speaker responsive to the power control signal.

An electronic device having an outer surface, the electronic device comprising:

• a speaker;
• an adaptive control circuit configured to receive an audio input signal responsive to an audio input power to the speaker;
• a temperature sensor configured to sense a temperature internal to the electronic device, wherein a temperature signal responsive to the sensed temperature is input to the adaptive control circuit;
• wherein responsive to the audio input signal and the temperature signal a power control signal is computed by the adaptive control circuit so that a temperature of the surface of the electronic device at a later time approaches a previously determined target temperature;
• and
• an audio limiter configured to limit the audio input power to the speaker responsive to the power control signal, wherein responsive to the audio input power to the speaker, a temperature is predicted of the surface of the electronic device after a sampling time interval of said sensing the temperature.