Date of Award

2002

Level of Access

Open-Access Thesis

Degree Name

Master of Science in Electrical and Computer Engineering (MSECE)

Department

Electrical and Computer Engineering

Advisor

Donald M. Hummels

Second Committee Member

Fred H. Irons

Third Committee Member

Ioannis Papantonopoulos

Abstract

This thesis provides an improved calibration and compensation scheme for pipeline Analog-to-Digital Converters (ADCs). This new scheme utilizes the intermediate stage outputs in a pipeline to characterize error mechanisms in the architecture. The goal of this compensation scheme is to increase the dynamic range of the ADC. The pipeline architecture is described in general, and tailored to the 1.5 bitslstage topology. Dominant error mechanisms are defined and characterized for an arbitrary stage in the pipeline. These error mechanisms are modeled with basis functions. The traditional calibration scheme is modified and used to iteratively calculate the error characteristics. The information from calibration is used to compensate the ADC. The calibration and compensation scheme is demonstrated both in simulation and using a custom hardware pipeline ADC. A 10-bit 5 MHz ADC was designed and fabricated in 0.5 pm CMOS to serve as the demonstration platform. The scheme was successful in showing improvements in dynamic range while using intermediate stage outputs to efficiently model errors in a pipeline stage. An application of the technique on the real converter showed an average of 8.6 dB improvement in SFDR in the full Nyquist band of the ADC. The average improvement in SINAD and ENOB are 3.2 dB and 0.53 bits respectively.

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