Abstract:
Analog-to-Digital Data Converters (ADCs) used in instrumentation and
measurements often require high absolute accuracy, including excellent linearity and
negligible dc offset. Incremental data converters (IDCs) provide a solution for such
measurement applications. Since IDCs are essentially delta-sigma converters
with reset operation before each conversion, they retain most of the advantages of
conventional [delta sigma] converters, and yet they are capable of offset-free and accurate
conversion.
Most of the previous research on incremental converters is for single-channel
and dc signal applications, where they can perform extremely accurate data conversion
with more than 20-bit resolution. In this thesis, the operation and the performance of
IDCs in both frequency and time domain is analyzed. Design techniques for
implementing multiplexed IDCs to convert narrow bandwidth ac signals are discussed
too. It incorporates the operation principles, modulator topologies, digital filter design
and signal-to-noise ratio optimization methodology. The theoretical analysis is
verified by simulation results.
