Title :
Realization of a digital PWM power amplifier using noise and ripple shaping
Author :
Smith, Mark K. ; Smedley, Keyue M. ; Ma, Yunhong
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Irvine, CA, USA
Abstract :
A digital pulse width modulation technique featuring noise and ripple shaping (NRS) for audio power amplification is realized. The sampled and extrapolated power source amplitude signal is used to shape the interpolated input digital signal. This shaped signal is fed to a noise shaper to produce a reduced bit digital signal fully representing the original signal. The output power signal is not affected by the requantization error or the power source ripple. Therefore, DC power regulators can be eliminated without sacrificing the signal to noise ratio. A digital signal processor controlled full bridge power amplifier was built with close to 5 kHz bandwidth and 40 dB ripple rejection improvement at 60 Hz over conventional PWM power amplifiers
Keywords :
PWM power convertors; audio-frequency amplifiers; bridge circuits; digital signal processing chips; interference (signal); power amplifiers; power supplies to apparatus; signal processing; 50 kHz; 60 Hz; DC power regulators; digital PWM power amplifier; digital pulse width modulation; digital signal processor; extrapolated power source amplitude signal; full bridge power amplifier; interpolated input digital signal; noise shaper; noise shaping; power source ripple; reduced bit digital signal; requantization error; ripple shaping; Digital modulation; Noise reduction; Noise shaping; Power amplifiers; Power generation; Pulse amplifiers; Pulse shaping methods; Pulse width modulation; Regulators; Space vector pulse width modulation;
Conference_Titel :
Power Electronics Specialists Conference, 1995. PESC '95 Record., 26th Annual IEEE
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-2730-6
DOI :
10.1109/PESC.1995.474798
