Resonation-based Cascade ΣΔ Modulators for High-Linearity Broadband A/D Conversion

Resonation-based cascade ΣΔ modulator for broadband low-voltage A/D conversion

This letter presents a novel cascade ΣΔ modulator architecture that employs inter-stage resonation to increase its effective resolution compared to traditional cascades while presenting very relaxed output swing requirements and, subsequently, high robustness to non-linearities of the amplifiers. In addition, the use of loop filters based on Forward-Euler integrators, instead of Backward-Euler ...

High-Efficiency Cascade ΣΔ ADCs for Software-Defined-Radio Mobile Systems

Abstrac t This paper discusses a number of techniques to implement efficient cascade ΣΔ modulators intended for low-voltage, wideband, multi-mode applications. Several architectural strategies – such as loop-filter order reconfiguration and concurrency – are embedded in SMASH topologies with unity signal transfer function and resonation in order to improve the performance, while keeping high ro...

Resonation-based Hybrid Continuous-Time/Discrete-Time Cascade ΣΔ Modulators − Application to 4G Wireless Telecom

This paper presents innovative architectures of hybrid Continuous-Time/Discrete-Time (CT/DT) cascade ΣΔ Modulators (ΣΔMs) made up of a front-end CT stage and a back-end DT stage. In addition to increasing the digitized signal bandwidth as compared to conventional ΣΔMs, the proposed topologies take advantage of the CT nature of the front-end ΣΔM stage, by embedding anti-aliasing filtering as wel...

A flexible resonation-based cascade ΣΔ modulator with simplified cancellation logic

POWER-Area-Performance Characteristics of FPGA-based Sigma-Delta FIR Filters

While one-bit ΣΔ modulators are widely used in Analog to Digital conversion stages due to their inherent linearity and precision, it is less common for the entire digital processing path to operate in single bit mode at the oversampled rate of the conversion system. The conventional approach has been to decimate the signal bit stream after conversion and for the remaining processing to be perfo...