Title :
A Sigma-Delta class D audio power amplifier in 0.35μm CMOS technology
Author :
Pan, Junle ; Yao, Libin ; Lian, Yong
Author_Institution :
Dept. of Electr. & Comput. Eng., VLSI Lab. Nat. Univ. of Singapore, Singapore
Abstract :
This paper presents a single chip class D audio power amplifier realized in a 0.35 mum CMOS technology. This chip consists of a high-linear single-loop feed-forward Sigma-Delta modulator with three level quantizer and a full H-bridge output stage. The three-level quantizer effectively reduces the switching activity of the output stage, especially when the input signal amplitude is low, hence improves the power efficiency. Direct feedback from H-bridge output improves the linearity of the amplifier. With a 3.3-V supply voltage and 4-Ohm load, the amplifier can deliver maximum 1-W output power with THD less than 0.8% at 8 kHz and reaches a maximum power efficiency more than 80%.
Keywords :
CMOS integrated circuits; audio-frequency amplifiers; feedback; power amplifiers; sigma-delta modulation; CMOS technology; Sigma-Delta class D audio power amplifier; direct feedback; frequency 8 kHz; full H-bridge output stage; high-linear single-loop feed-forward Sigma-Delta modulator; power 1 W; three level quantizer; voltage 3.3 V; CMOS technology; Delta-sigma modulation; Feedforward systems; High power amplifiers; Power amplifiers; Pulse amplifiers; Pulse width modulation; Quantization; Signal to noise ratio; Topology; ΔΣ modulation; 1.5bit quantization; feedforward;
Conference_Titel :
SoC Design Conference, 2008. ISOCC '08. International
Conference_Location :
Busan
Print_ISBN :
978-1-4244-2598-3
Electronic_ISBN :
978-1-4244-2599-0
DOI :
10.1109/SOCDC.2008.4815561
