A Zoom Architecture Using Linear-Exponential Incremental ADC

WThis paper presents a zoom linear-exponential incremental analog-to-digital convertor (LE-IADC). A two-phase LE-IADC using second-order noise coupling (NC) is employed as the fine ADC. The second-order NC could further expedite the accumulation of the IADC, compared with the prior art using first-order NC. Therefore, it results in a higher theoretical resolution. However, such higher-order NC gives rise to an extremely poor maximum stable amplitude (MSA). Thanks to the zoom topology, the MSA loss could be inherently compensated. Mathematical analysis and behavioral-level simulation results are presented to confirm the principle of the proposed zoom LE-IADC.