SYSTEMS AND METHODS FOR DETECTION OF LOAD IMPEDANCE OF A TRANSDUCER DEVICE COUPLED TO AN AUDIO DEVICE

摘要

In accordance with systems and methods of the present disclosure, an audio device may include an electrical terminal, an audio circuit, and a transducer load detection circuit. The electrical terminal may couple a transducer device to the audio device. The audio circuit may generate an analog audio signal, wherein the analog audio signal is coupled to the electrical terminal. The transducer load detection circuit may detect a load impedance of the transducer device when the transducer device is coupled to the audio device from characteristics measured at the electrical terminal.

主权项

1. A method comprising:
providing from a charge pump power supply a power supply voltage to a power supply input of a power amplifier having an audio input configured to receive an audio input signal, and an audio output configured to generate an analog audio signal for playback at a transducer device having a load impedance and coupled to the audio output via an electrical terminal; detecting a peak amplitude of a voltage ripple of the power supply voltage in response to a transition of the analog audio output signal; detecting a peak amplitude of a change in a digital audio input signal that causes the transition of the analog audio output signal, wherein the digital audio input is input to a digital-to-analog conversion circuit coupled to the power amplifier and configured to convert a digital audio input signal into the analog audio input signal; and estimating a value of the load impedance based on the peak amplitude of the voltage ripple and the peak amplitude of the change in the digital audio input signal.