Patent ID: 6107876
Filing Date: 2000-08-22
Classification: H03F

Abstract:
A digital input switching audio power amplifier, comprising:a serial interface which creates a parallel data stream from a serial digital signal provided thereto;a volume control element in communication with said serial interface for scaling said parallel data stream;an interpolation and/or an oversampling filter in communication with said volume control element for increasing the sample rate;a linearizer in communication with said interpolation and/or oversampling filer for correcting a pulse width value that is already applied to the signal;a noise shaper in communication with said linearizer for compensating for distortion by converting a signal received from said linearizer to a lower resolution by adding a moving offset to the incoming data to allow for lower noise in the audio range and higher noise above the audio range;a pulse width modulator (PWM) in communication with said noise shaper for comparing a signal received from said noise shaper with either a ramp signal or a triangle waveform, either of which is digitally synthesized and limited;a delay timing control function in communication with said PWM for adding a delay to prevent shoot-through on an output stage; andan output stage in communication with said delay timing control function for driving an output device.