A variable bandwidth & IF, continuous time ΔΣ modulator for low power low-IF receivers

Author

Atac, Aytac ; Wunderlich, Ralf ; Heinen, Stefan

Author_Institution

Dept. of Integrated Analog Circuits & RF Syst., RWTH Aachen Univ., Aachen, Germany

fYear

2011

fDate

26-29 June 2011

Firstpage

362

Lastpage

365

Abstract

This paper presents a novel continuous time ΔΣ modulator for multi-mode operation. The design is targeted for low power, low IF multi-mode receivers and could operate on any bandwidth ranging from 0.5MHz to 1.5MHz while using the same architecture. A 3rd order, quadrature bandpass (QBP) modulator is preferred that operates on a single side of the frequency spectrum and hence improves the noise shaping characteristic. Weighted capacitive feedforward (WCFF) method is developed and analyzed to achieve the required bandwidths and IF for multi-mode operation. The achieved SNR values are 68.7/60.6/50.4dB for 0.5/1/1.5MHz bandwidths respectively, while consuming a total average current of 1.8mA from a 1.2V supply. The design is simulated with UMC 0.13μm technology.

Keywords

delta-sigma modulation; feedforward; low-power electronics; noise; receivers; 3rd order quadrature bandpass modulator; continuous time ΔΣ modulator; frequency 0.5 MHz to 1.5 MHz; low-power low-IF receivers; multimode operation; noise shaping; size 0.13 mum; voltage 1.2 V; weighted capacitive feedforward method; Bandwidth; CMOS integrated circuits; Feedforward neural networks; Frequency modulation; Receivers; Transfer functions;

fLanguage

English

Publisher

ieee

Conference_Titel

New Circuits and Systems Conference (NEWCAS), 2011 IEEE 9th International

Conference_Location

Bordeaux

Print_ISBN

978-1-61284-135-9

Type

conf

DOI

10.1109/NEWCAS.2011.5981245

Filename

5981245