An eighth-order bandpass ΔΣ modulator for A/D conversion in digital radio

Author

Louis, Loai ; Abcarius, John ; Roberts, Gordon W.

Author_Institution

Dept. of Electr. Eng., McGill Univ., Montreal, Que., Canada

Volume

34

Issue

4

fYear

1999

fDate

4/1/1999 12:00:00 AM

Firstpage

423

Lastpage

431

Abstract

This paper examines the design and implementation of an eighth-order bandpass delta-sigma modulator. The design process is investigated from the signal flow graph level, through to the details of the switched capacitor implementation and layout considerations. Simulation results, highlighting the effects of process variation, are provided and the experimental performance of the modulator described. The modulator is implemented in a 0.8-μm BiCMOS process and occupies an active area of 1.7 mm². Operating from ±2.5-V supplies, the fabricated prototype exhibits stable behaviour and achieves a dynamic range of 67 dB over a 200-kHz bandwidth centered at the commonly used intermediate frequency of 10.7 MHz. This paper, therefore, demonstrates the viability of high-order single-bit bandpass delta-sigma modulation

Keywords

BiCMOS integrated circuits; delta-sigma modulation; digital radio; radio equipment; signal flow graphs; switched capacitor networks; 0.8 micron; 10.7 MHz; 2.5 V; 200 kHz; A/D conversion; BiCMOS process; design; digital radio; dynamic range; eighth-order bandpass delta-sigma modulator; layout; signal flow graph; simulation; switched capacitor circuit; Bandwidth; BiCMOS integrated circuits; Capacitors; Delta modulation; Dynamic range; Flow graphs; Frequency; Process design; Prototypes; Signal design;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/4.753675

Filename

753675