Title :
A single-chip audio system with delta-sigma DAC and class-D amplifier
Author :
Yasuda, Akira ; Ohkubo, Akinori ; Ogata, Katsuya ; Ueno, Hajime ; Anzai, Takeshi ; Kimura, Takashi ; Ochiai, Koichiro ; Hamasaki, Toshihiko
Author_Institution :
Fac. of Eng., Hosei Univ., Tokyo
Abstract :
In this paper, we present a single-chip delta-sigma DAC and a class-D amplifier that utilizes internal antialias low-pass filters (LPF). The clock frequency of the delta-sigma modulator is lower than that of the delta-sigma DAC in order to reduce the power loss. The use of a closed-loop class-D amplifier with a balanced structure synchronized by a common-mode clock signal can drastically reduce aliasing noise and increase the LPF cutoff frequency. The chip area of the antialias LPF is reduced by one-hundredth. The test chip is fabricated by 0.35-mum CMOS technology. The measured SNR, dynamic range, and THD of the test chip for audio applications are 94.7 dB, 95.0 dB, and 0.19 dB, respectively
Keywords :
audio systems; delta-sigma modulation; low-pass filters; power amplifiers; 0.35 micron; CMOS technology; LPF; aliasing noise reduction; antialias low-pass filters; closed-loop class-D amplifier; common-mode clock signal; delta-sigma DAC; delta-sigma modulator; digital-analog converter; internal low-pass filters; microfabrication; power loss reduction; single-chip audio system; Audio systems; CMOS technology; Clocks; Cutoff frequency; Delta modulation; Frequency synchronization; Low pass filters; Noise reduction; Semiconductor device measurement; Testing;
Conference_Titel :
Circuits and Systems, 2006. ISCAS 2006. Proceedings. 2006 IEEE International Symposium on
Conference_Location :
Island of Kos
Print_ISBN :
0-7803-9389-9
DOI :
10.1109/ISCAS.2006.1693939
