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access icon free Compact on-the-fly-enabled termination with high-current density and ESD compliance

In wireline communication systems, InterSymbol Interference (ISI) may also occur by termination mismatch at either end of a long channel. Termination resistors, characteristic channel impedance, and connectors may get altered by temperature and supply voltage variations during operation. Wireline front-ends may exercise on-the-fly termination calibration to mitigate ISI during operation. Here the authors demonstrate the impact on signal integrity of an on-the-fly termination calibration using moderated coarse calibration steps. They introduce a resistance termination calibration scheme that enables fine steps and considers high-current density effects during ElectroStatic Discharge events. The simulation results of an implemented calibration scheme within a front-end operating at 3.2 Gb/s ensure open data eyes during on-the-fly termination calibration. A comparison with a conventional scheme illustrates how coarse calibration generates undesired reflected waves, handicapping signal integrity.


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