Title :
Switching-based topologies for high-efficiency audio amplifiers
Author :
Saponara, Sergio ; Terreni, Pierangelo
Author_Institution :
Dept. of Inf. Eng., Pisa Univ., Italy
Abstract :
The paper describes the PCB-realization of two high-efficiency amplifiers for consumer audio applications. A 35 Wrms output power delivered to an 8 Ω speaker is referred as case study. The first architecture implements a switching amplifier with 3-state pulse width modulation (PWM) while the second solution is an hybrid topology: a linear amplifier is assisted by a switching (buck) converter to increase efficiency for output power higher than 2 Wrms. Compared to conventional linear and class D amplifiers the proposed schemes allow for good performances in terms of harmonic distortion and power efficiency with different trade-offs: the hybrid topology achieves a 0.11% distortion for a 77% power efficiency while the 3-state PWM switching amplifier features a 91% efficiency and a 0.23% distortion.
Keywords :
audio-frequency amplifiers; harmonic distortion; network topology; power amplifiers; printed circuits; pulse width modulation; 35 W; 8 ohm; PCB; audio amplifiers; buck converter; harmonic distortion; linear amplifier; pulse width modulation; switching amplifier; switching converter; switching topologies; Filters; Harmonic distortion; High power amplifiers; Portable computers; Power amplifiers; Power generation; Pulse amplifiers; Pulse width modulation; Pulse width modulation inverters; Topology;
Conference_Titel :
Signals, Circuits and Systems, 2005. ISSCS 2005. International Symposium on
Print_ISBN :
0-7803-9029-6
DOI :
10.1109/ISSCS.2005.1509909
