A 114-AF RMS- Resolution 46-NF/10-MΩ -Range Digital-Intensive Reconfigurable RC-to-Digital Converter with Parasitic-Insensitive Femto-Farad Baseline Sensing

This paper presents a digital-intensive dynamically reconfigurable RC-to-digital converter with an input range of 46 nF/10 MΩ, suitable for reading out R or C sensors in a time-interleaved way. Its reconfigurability also allows parasitic-insensitive sensing of femto-farad baseline capacitances. Implemented in a 0.18-μm CMOS process, it uses a swing-boosted period-modulation (SB-PM) frontend, achieving a capacitance resolution of 114 aF
_rms
corresponding to an FOM of 4.04 pJ/conversion-step from a 1-V supply.