On the Transfer Behaviour of Incremental Σ Δ Converters

Abstract:
An incremental Σ Δ Analog to Digital Converter is a mixed analog and digital system with reset of internal states, resulting in a time varying system as a first approximation. During system design it is important to know the transfer function towards the output under the event of resets. Knowing this transfer function makes it possible to determine the impact of noise and aliasing during one conversion phase. A new approach is presented employing methods of linear and time invariant (LTI) systems to derive transfer functions for this special kind of time varying system.