Mismatch-tolerant Capacitor Array Structure for Junction-splitting SAR Analog-to-digital Conversion

Abstract

A new junction-splitting based SAR ADC with a redundant searching capacitor array structure in 0.13 mu m CMOS process to alleviate capacitor mismatch effects, is presented. The normalized average power has a factor of 0.35 to the conventional SAR ADC at 10-bit conversion accuracy. Statistical experiments show the number of missing codes resulting from the mismatch reduces by 95% for 3% unit-capacitor mismatch ratio, while keeping the conversion energy to that of the conventional JS capacitor array.