A 24b 2MS/s SAR ADC with 0.03ppm INL and 106.3dB DR in 180nm CMOS
J. Steensgaard, R. C. Reay, Raymond P. Perry, Dave Thomas, Geoffrey Tu, George Reitsma
Abstract
This work aims at optimizing accuracy, noise, and power for low-to-medium speed applications. The ADC function accommodates a wide range of use, including Nyquist-rate data acquisition and oversampled signal applications. The noise spectral density (NSD) is uniform from 0Hz to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathsf{Fs}/2=1 \mathsf{MHz}$</tex> , and hence <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathsf{FoM}1= \mathsf{DR} +10\cdot \log$</tex> (BW/Power) is the same for any BW selected by decimation filtering or other DSP. The SNDR is within 1 dB of the DR for full-scale input tones at frequencies up to 100kHz, and hence <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathsf{FoM}2= \mathsf{SNDR} +10\cdot\mathsf{log}$</tex> (BW/Power) is similar to FoM1 for the primary use cases.