Band Pass Noise-Shaping Dynamic Element Matching for VCM based SAR-Assisted Pipeline ADCs

• Autor(a) principal: Loução, Rafael Filipe Gomes de Almeida
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: http://hdl.handle.net/10362/178187
• topic: Mismatch; DEM; DWA; SAR; Noise-Shaping; Band-Pass; Domínio/Área Científica::Engenharia e Tecnologia::Nanotecnologia

As the drive for more powerful and capable Analog to Digital Converters (ADCs) increases, so does the need for error mitigation techniques. Components’ mismatch significantly degrades the performance of ADCs by introducing non-linearities that cause high energy spurs in its output spectra. Dynamic Element Matching (DEM) techniques allow for the mitigation and filtering of mismatch error’s spectral influence, known as noise-shaping. Although these tech- niques are most commonly used in Σ∆ ADCs, given that these operate with relatively high Over- sampling Ratios (OSRs) and in the low frequency regime, this work will extend a Data Weight Averaging (DWA) DEM technique to the Successive Approximation Register (SAR) architecture enhanced by the pipeline topology for a band-pass operation and a low Oversampling Ratio (OSR). This extension allows for the utilization of filter transfer functions that are embedded in the DEM technique as general as H (z) = 1 ± Z −a affecting only the mismatch error. The DEM method, accompanied by an output digital filter, results in the significant increase of the Signal to Noise and Distortion Ratio (SNDR) as well as the Spurious Free Dynamic Range (SFDR) of the converter. This work provides the mathematical demonstration and conceptual explanation, the methods to analyze, and the digital implementation required to realize the referred DEM technique.