| 摘要 |
PURPOSE: A digital feedback amplifier is provided to minimize errors generated by the ripple and noise of a supplied power source as well as switching delay generated in a switching amplifier. CONSTITUTION: A digital feedback amplifier comprises a reference saw tooth wave generator (100), an error signal generator (200), a correction signal generator (300), a switching amplifier (400), and a feedback circuit (500). The reference saw tooth wave generator integrates the inverted signal of a pulse-width modulation (PWM) input signal and initializes in the pulse edge of the PWM input signal to generate a reference saw tooth wave. The error signal generator generates an error signal based on difference between a feedback signal and the PWM input signal. The correction signal generator compares the error signal with the reference saw tooth wave to generate a correction signal. The switching amplifier generates an output signal by switching depending on the correction signal. The feedback circuit normalizes the output signal to match the levels of the output signal and the PWM input signal and generates the feedback signal. [Reference numerals] (100) Reference saw tooth wave generator; (200) Error signal generator; (300) Correction signal generator; (400) Switching amplifier; (500) Feedback circuit; (AA) Input signal; (BB) Output signal |
