PREDICTIVE FEEDBACK COMPENSATION FOR PWM SWITCHING AMPLIFIERS

摘要

Methods and systems are disclosed for predictive feedback compensation (PFC) circuitry for suppressing distortions caused by supply voltage variations and output amplitude switching non-idealities in pulse width modulated (PWM) switching amplifiers by pre-compensating the PWM input based upon the supply voltage or output pulse amplitude. Output amplitude errors associated with previous PWM output signals are used to predict output amplitude errors expected for future PWM output signals. These predicted output amplitude errors are then used to adjust the pulse widths for the future PWM output signals. Closed loop width adjustment can also be applied by providing timing feedback signals associated with the pre-compensation of the PWM input signals. Traditional feedback techniques can also be used in conjunction with the predictive feedback compensation (PFC) circuitry.