A Pipelined-SAR-TDC with Time-Domain Noise-Shaping Self-Calibration

We introduce a new architecture of a pipelined SAR time-to-digital converter (TDC) operating at 800 MS/s. To overcome the problem of high nonlinearity and performance variability in prior art, a time-domain noise-shaping (NS) self-calibration technique is proposed. It boosts SFDR by 20 dB achieving 55 dB, yielding the best-in-class 96% bit-utilization (ENOB/NOB) and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{FoM}_{\mathrm{w}}$</tex> of 40 fJ/conv-step. Measurements across supply variations and multiple ICs validate the efficacy of the proposed approach.