A capacitor-mismatch-insensitive switch-capacitor amplifier for Pipeline ADC

A new approach to achieve a switched-capacitor amplifier (SCA) for pipeline ADC with reduced sensitivity to capacitors' mismatches is presented in this paper. It uses a operational transconductance amplifier (OTA) in two phases to produce the gain of two. In addition , a low-power CMOS OTA with near rail-to-rail output swing is presented. The proposed circuit is based on the current-mirror OTA topology. Comparing to the conventional SCA , the mismatches between the capacitors has a very smaller influence on the accuracy of the gain of two, and the OTA achieves high dc gain and good gain-bandwidth. The integrated circuit is designed in a 0.18 mum CMOS process.