In recent years, the research toward the development of high speed and high resolution analog-to-digital converters (ADCs) has been equally driven by the demand of high-speed wire line and wireless communication services. Delta-Sigma ADCs are widely used in wireless applications due to their oversampling and noise shaping characteristics. This thesis aims to design a continuous-time sigma-delta...

Single-bit second-order delta-sigma modulators are commonly used in high-resolution ADCs. Testing this type of modulator requires a high-resolution test stimulus, which is difficult to generate. This paper proposes a novel and robust technique to determine the performance of the modulator, which incorporates simple design-for-testability circuitry. This technique requires only digital stimulus ...

We present a globally stable arbitrary-order single-bit delta-sigma modulator architecture with continuous-time loop filtering. Using Lyapunov arguments and the method of equivalent control, it is shown that stability is guaranteed for any input signal with peak magnitude less than L > 0, where L and +L denote the quantization levels. The design augments the conventional deltasigma modulator wi...

This paper describes an implementation of a bandpass sigma-delta modulator behavioral model with SIMPLORER VHDL-AMS. The model includes most of the non-idealities which affect the performance of the component, such as sampling jitter, kT/C noise and operational amplifier parameters. A comparison with another model, implemented with MATLABSIMULINK by Brigati et al., is made to highlight and val...

In this paper a reconfigurable switched-current sigma delta modulator for power amplifier is shown, which is a suitable topology to save energy and integrated area in portable applications. Results have shown the correct operation of a 1.8V, 0.18μm CMOS reconfigurable switched-current sigma delta modulator with 11bits dynamic range within 1MHz and 7.8bits within 3.8MHz bandwidth.

The paper deals with a novel approach to processing of pressure sensor signals. A bandpass sigma-delta modulator is used for this purpose. This technique is relatively new and it is not used widely, because this kind of modulator is usually utilized for wireless and video applications. Since the bandpass sigma-delta modulator works within its defined band it is resistant to offsets of its subci...

A method for improving the signal-to-noise ratio (SNR) of sigma–delta modulators with one-bit quantization is presented. The two-level feedback signal of a standard sigma–delta modulator is replaced by a multilevel signal, which is a superposition of two parts. One part ( ) represents a rough estimate of the instantaneous amplitude of the input signal (prediction signal), and the other ( ) is t...

A new design approach of a digital delta-sigma modulator with small output fluctuation is proposed. The digital delta-sigma modulators are used in the digital-analog converters, the fractional-N phase lock loop, etc. and its output fluctuation is one of the important performances although a higher order modulator often produces large fluctuations. In this work, the noise shaping filter of the m...

Single-bit second-order delta-sigma modulators are commonly used in high-resolution ADCs. This type of modulator requires high-resolution test stimulus, which is difficult to generate. This paper proposes a novel and robust technique to determine the performance of the modulator by characterizing its key parameters using a pseudo-random pattern sequence. This technique is suitable for BIST appl...