A 12-bit 50M samples/s digitally self-calibrated pipelined ADC

摘要

This thesis describes the different aspects of the design and implementation of a 12-bit 50M samples/s pipelined non-binary radix 1.9 analog-to-digital converter. The converter architecture is made up of 14 stages with an interstage gain of 1.9 (non-binary radix). Each stage is made of one fully differential sample-and-hold amplifier (SHA), a 1-bit sub-ADC (basically one comparator) and a 1-bit DAC. The sub-DAC functionality is rolled in as part of the SHA switch capacitor architecture which is referred to as the multiplying DAC (MDAC). The self-calibration function is performed in a cyclical fashion and the entire pipeline is used to perform the calibration for each stage. The settling time on the MDAC is about 9ns with a gain of approximately 8ldB. The entire pipeline has been implemented in a digital 0.35[Mu]m CMOS process.