Title :
Fourier series analysis of the nonlinearities in analog closed-loop PWM class D amplifiers
Author :
Shu, Wei ; Chang, Joseph S. ; Ge, Tong ; Tan, Meng Tong
Author_Institution :
Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ.,, Singapore
Abstract :
We derive Fourier series expressions for modeling analog closed-loop PWM class D amplifiers. Based on our derived expressions, we are able to analyze the mechanisms of several nonlinearities, specifically the power supply noise and fold-back distortions. We investigate the influence of the finite loop gain on these nonlinearities, and we show that those nonlinearities can be effectively suppressed by the higher loop gain. We verify our analysis by computer simulations and also on the basis of experimental measurements. The derived expressions are practically useful as they provide insights to a designer for PWM class D amplifier designs
Keywords :
Fourier series; analogue circuits; power amplifiers; power supply circuits; pulse width modulation; Fourier series analysis; PWM amplifiers; analog closed-loop amplifier; class D amplifiers; finite loop gain; fold-back distortions; nonlinearities; power supply noise; pulse width modulation; Computer simulation; Filters; Fourier series; Frequency; Heat sinks; MATLAB; Mathematical model; Power amplifiers; Power supplies; Pulse width modulation;
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.2006.1692852
