G. Chen, B. Liu, S. Nakatake and B. Yang, “Routability of twisted common-centroid capacitor array under signal coupling constraints,” 2016 IEEE 59th International Midwest Symposium on Circuits and Systems (MWSCAS), 2016, pp. 1-4, doi: 10.1109/MWSCAS.2016.7870152.

Abstract

At present, the layout of on-chip matching capacitors with high relative accuracy is solved . The distortion proposed in this paper CC It is placed in consideration of routability while reducing system mismatch caused by process gradient . We and spiral Method in SAR ADC On , Its have 1. Lower capacitance ratio mismatch ;2.100% Cabling success rate of .

research

Signal coupling constraints
Two capacitors of the same unit should not cross , Will cause additional coupling .

Two layer wiring success rate 100%

Data sets

Difference successive approximation ADC 65nm

Experimental index

and spiral Manual wiring required 6 Layer by layer A little metal layer is used .

SAR ADC INL DNL , All ratio spiral Many small .
【 Why is it divided into LSB MSB?】

The specific methods