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

fYear

2010

fDate

May 30 2010-June 2 2010

Firstpage

289

Lastpage

292

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;

fLanguage

English

Publisher

ieee

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

Type

conf

DOI

10.1109/ISCAS.2010.5537868

Filename

5537868