Direct measurement of an input signal to a loudspeaker to determine and limit a temperature of a voice coil of the loudspeaker
AssigneeMaxim Integrated Products, Inc.
InventorRobert Polleros
Life of this patent
Estimating the term…
Abstract
Aspects of the disclosure pertain to a system and method for providing temperature limiting for a voice coil of a speaker. The system and method provide the aforementioned temperature limiting based upon monitoring (e.g., measurement) of an amplifier output signal provided to the speaker. Providing the aforementioned temperature limiting promotes improved protection for the speaker.
Claims17
A system for providing temperature limiting for a voice coil of a speaker, comprising:
- an amplifier connected to the speaker, the amplifier configured for receiving an amplifier input signal, generating an amplifier output signal based upon the amplifier input signal and transmitting the amplifier output signal to the speaker;
- a sensing circuit connected to the amplifier, the sensing circuit configured for measuring a voltage and a current of the amplifier output signal and providing an output signal including a measured voltage and a measured current;
- a resistance estimator module including a processor, the resistance estimator module connected to the sensing circuit, the resistance estimator module configured for receiving the measured current and the measured voltage, calculating an estimated resistance of the voice coil based upon the measured voltage and the measured current by dividing a root mean square value of the measured voltage and the measured current, and providing an output including the estimated resistance;
- and
- a temperature estimator module connected to the resistance estimator module, the temperature estimator module being configured for receiving the resistance estimator module output and calculating a temperature of the voice coil based upon the estimated resistance,
- wherein the amplifier input signal is attenuated based upon a comparison of the calculated temperature of the voice coil against a pre-determined threshold temperature of the voice coil.
A method for providing temperature limiting for a voice coil of a speaker of a speaker system, comprising:
- receiving an audio input signal at an audio gain circuit of the system;
- based upon the received audio input signal, producing an audio gain circuit output via the audio gain circuit;
- combining the audio gain circuit output with a stimulus signal to produce an amplifier input signal;
- receiving the amplifier input signal via an amplifier of the system;
- transmitting an output signal from the amplifier to the speaker of the system, the amplifier output signal being derived from the amplifier input signal, the amplifier output signal including a voltage and a current;
- measuring the voltage and current of the amplifier output signal, via a sensing circuit;
- and
- calculating an estimated resistance of the voice coil, via a resistance estimator module, by dividing a root mean square value of the measured voltage and the measured current.
A non-transitory computer-readable medium having computer-executable instructions for performing a method for providing temperature limiting for a voice coil of a speaker of a speaker system, the method comprising:
- receiving an audio input signal at an audio gain circuit of the system;
- based upon the received audio input signal, producing an audio gain circuit output via the audio gain circuit;
- combining the audio gain circuit output with a stimulus signal to produce an amplifier input signal;
- receiving the amplifier input signal via an amplifier of the system;
- transmitting an output signal from the amplifier to the speaker of the system, the amplifier output signal being derived from the amplifier input signal, the amplifier output signal including a voltage and a current;
- measuring the voltage and the current of the amplifier output signal, via a sensing circuit;
- calculating an estimated resistance of the voice coil, via a resistance estimator module, by dividing a root mean square value of the measured current and the measured voltage;
- and
- transmitting the calculated resistance from the resistance estimator module to a temperature estimator module of the system.
Dependencies are inferred from the claim text.