Abstract: A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

Abstract: A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

Abstract: A system and method for performing speaker load diagnostics. A digital signal processor generates a diagnostic tone that is provided to the speaker. The diagnostic tone is generated using an oscillator internal to the digital signal processor. The digital signal processor receives current and voltage data from the speaker based on the diagnostic tone, and processes the current and voltage data to determine whether a fault condition exists in the speaker.

Abstract: A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

Abstract: A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

Abstract: A boosted audio amplifier system includes a first digital interpolation filter configured to oversample an audio input signal at a first oversampling rate and includes a signal level detector having an input coupled to receive the oversampled audio input signal and configured to produce an audio input level signal. The system further includes a programmable delay buffer having inputs coupled to receive the oversampled audio input signal and a first delay signal. The programmable delay buffer adds a first delay to the oversampled audio input signal to produce a delayed input signal. The system also includes a first processor having inputs coupled to receive a battery voltage level signal, the audio input level signal and the first delay signal. The first processor is configured to produce boost control signals to regulate a boost voltage.

Abstract: A system and method for performing speaker load diagnostics. A digital signal processor generates a diagnostic tone that is provided to the speaker. The diagnostic tone is generated using an oscillator internal to the digital signal processor. The digital signal processor receives current and voltage data from the speaker based on the diagnostic tone, and processes the current and voltage data to determine whether a fault condition exists in the speaker.

Abstract: A boosted audio amplifier system includes a first digital interpolation filter configured to oversample an audio input signal at a first oversampling rate and includes a signal level detector having an input coupled to receive the oversampled audio input signal and configured to produce an audio input level signal. The system further includes a programmable delay buffer having inputs coupled to receive the oversampled audio input signal and a first delay signal. The programmable delay buffer adds a first delay to the oversampled audio input signal to produce a delayed input signal. The system also includes a first processor having inputs coupled to receive a battery voltage level signal, the audio input level signal and the first delay signal. The first processor is configured to produce boost control signals to regulate a boost voltage.