Improved wideband low distortion cascaded delta-sigma modulator

Author

Yuan, Xiaolong ; Gothenberg, Andreas ; Wu, Xiaobo

Author_Institution

KTH-ZJU Joint Res. Center of SoC, Zhejiang Univ., Hangzhou, China

fYear

2005

fDate

20-24 July 2005

Firstpage

160

Lastpage

164

Abstract

It has recently become very popular to feedforward the input signal in wideband delta-sigma modulators, so that the integrators only process quantization errors. The advantage being that the actual signal is not distorted by opamp and integrator nonlinearities. In this paper, we focus on improved feedforward techniques for cascaded delta-sigma modulators. A feedforward cascaded structure is presented based on unity-gain signal transfer function (STF) and optimized noise transfer function (NTF) zero placement, using λ-analysis. The proposed structure has improved signal-to-noise-ratio (SNR) across the entire input range.

Keywords

delta-sigma modulation; feedforward; transfer functions; cascaded delta-sigma modulator; feedforward cascaded structure; noise transfer function; quantization error; signal transfer function; signal-to-noise-ratio; wideband delta-sigma modulator; Circuits; Delta modulation; Noise reduction; Noise shaping; Quantization; Signal processing; Signal to noise ratio; Transfer functions; Voltage; Wideband;

fLanguage

English

Publisher

ieee

Conference_Titel

System-on-Chip for Real-Time Applications, 2005. Proceedings. Fifth International Workshop on

Print_ISBN

0-7695-2403-6

Type

conf

DOI

10.1109/IWSOC.2005.75

Filename

1530934