Systematic methodology for designing reconfigurable ΔΣ modulator topologies for multimode communication systems

ABSTRACT

This paper proposes a methodology for designing reconfigurable continuous-time ΔΣ modulator topologies. The methodology is based on the concept of generic topology that expresses all possible signal paths in a reconfigurable topology. Topologies are optimized for minimizing the complexity of the topologies, maximizing the sharing of circuitry for different modes, maximizing the topology robustness with respect to circuit nonidealities, and minimizing total power consumption. The paper presents a case study for designing topologies for a three mode reconfigurable ΔΣ modulator, and compares topologies with state-of-the-art design.

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