AES New York 2013
Paper Session P10
P10 - Amplifiers
Friday, October 18, 2:00 pm — 2:30 pm (Room 1E07)
Chair:
Alexander Voishvillo, JBL/Harman Professional - Northridge, CA, USA
P10-1 Supply-Feedback Fully-Digital Class D Audio Amplifier Featuring 100 dBA+ SNR and 0.5 W to 1 W Selectable Output Power—Rossella Bassoli, ST-Ericsson - Monza Brianza, Italy; Federico Guanziroli, ST-Ericsson - Monza Brianza, Italy; Carlo Crippa, ST-Ericsson - Monza Brianza, Italy; Germano Nicollini, ST-Ericsson - Monza Brianza, Italy
This paper presents a real-time power supply noise correction technique in a fully-digital class D audio amplifier. The power supply is scaled and applied to a 12-bits Nyquist ADC to modify the amplitude of the Pulse-Width-Modulator reference carrier. An improved supply extrapolation algorithm results to a power supply rejection from one to two orders of magnitude higher than reported implementations. Class D sensitivity to clock jitter is presented. SNR higher than 100dBA have been measured in the presence of both power supply ripple and clock jitter. The PWM and output stage are integrated in the same chip in a 0.13µm digital CMOS technology, whereas an external ADC has been used to demonstrate the validity of the supply-feedback algorithm.
Convention Paper 8968 (Purchase now)
