Title :
A time encoded decimation filter for noise shaped power DACs
Author :
Hernandez, L. ; Fernandez, J. ; Prefasi, E. ; Paton, S.
Author_Institution :
Electron. Dept., Carlos III Univ. of Madrid, Leganes, Spain
fDate :
May 30 2010-June 2 2010
Abstract :
This paper presents a new approach to reduce the out of band energy in a class D amplifier driven by a DAC. The proposed architecture is based on a Time Encoded Filter (TEF). The TEF operates as a discrete time linear system on the pulse widths of a PWM signal rather than on the amplitudes of a sequence. It only requires RC circuits, comparators and digital logic. Hence, it can be integrated along with the D/A converter. The main advantage of this approach is that the number of power inductors and capacitors of the off chip low pass filter may be reduced.
Keywords :
RC circuits; amplifiers; comparators (circuits); digital-analogue conversion; discrete time filters; logic circuits; low-pass filters; pulse width modulation; D/A converter; PWM signal; RC circuits; class D amplifier; comparators; digital logic; discrete time linear system; low pass filter; noise shaped power DAC; pulse width; time encoded decimation filter; time encoded filter; Bandwidth; Circuits; Clocks; Delta-sigma modulation; Low pass filters; Noise shaping; Power amplifiers; Pulse amplifiers; Pulse width modulation; Space vector pulse width modulation;
Conference_Titel :
Circuits and Systems (ISCAS), Proceedings of 2010 IEEE International Symposium on
Conference_Location :
Paris
Print_ISBN :
978-1-4244-5308-5
Electronic_ISBN :
978-1-4244-5309-2
DOI :
10.1109/ISCAS.2010.5537868
