Title :
Highly selective `analog´ filters using ΔΣ based IIR filtering
Author :
Johns, D.A. ; Lewis, D.M. ; Cherepacha, D.
Author_Institution :
Dept. of Electr. Eng., Toronto Univ., Ont., Canada
Abstract :
Design equations and experimental results for a second-order delta-sigma (Σ-Δ) based infinite impulse response (IIR) filter are presented. Although input and output signals are analog, filtering is performed directly on an oversampled Δ-Σ modulated signal, thus eliminating the need for any decimation or interpolation filters. Circuit complexity consists of only a single Δ-Σ analog-digital (A/D) modulator, approximately ten 26-b adders, a 1-b digital-analog converter (D/A) and a low-pass filter. It is shown experimentally that such a filtering technique can realize filter pole-Q´s of at least 2600 in the audio frequency range
Keywords :
IIR filters; Q-factor; sigma-delta modulation; IIR filtering; adders; audio frequency range; delta-sigma based filter; digital-analog converter; highly selective filters; infinite impulse response; low-pass filter; oversampled Δ-Σ modulated signal; Adders; Analog-digital conversion; Complexity theory; Delta modulation; Digital modulation; Equations; Filtering; IIR filters; Interpolation; Low pass filters;
Conference_Titel :
Circuits and Systems, 1993., ISCAS '93, 1993 IEEE International Symposium on
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-1281-3
DOI :
10.1109/ISCAS.1993.393969
