BOUNDING THE INTEGRATOR OUTPUTS OF 2ND-ORDER SIGMA-DELTA MODULATORS

The development to date of the bounds for the outputs of the integrato rs of second-order sigma-delta modulators has relied on a mixture of t heoretical analysis and extensive use of simulation. This paper presen ts a new approach that analyzes the behavior of such systems, and iden tifies the external boundaries of the trapping region for the outputs of the integrators. With this approach, it is possible to develop tigh t results for the standard second-order modulator with constant input, without the need for simulation. This approach is flexible, and can b e adapted for other second-order architectures, and gives strong insig ht into the behavior of these systems.