Title :
Stability analysis of high-order modulators for delta-sigma ADCs
Author :
Baird, Rex T. ; Fiez, Terri S.
Author_Institution :
Electr. Eng. & Comput. Sci., Washington State Univ., Pullman, WA, USA
Abstract :
A model for Δ-Σ modulators that allows stability analysis using linear methods is presented. The analysis of a third-order modulator indicates that stability is a function of input amplitude, transients, and initial conditions. The delay introduced by integrator saturation is found to have a destabilizing effect, leading to invalid limit cycle behavior in high-order modulators. Assurance of stable modulator operation requires both proper choice of system parameters and limiting the delay caused by integrator saturation
Keywords :
circuit stability; delays; integrating circuits; limit cycles; sigma-delta modulation; transient analysis; delay; delta-sigma ADCs; destabilizing effect; high-order modulators; initial conditions; input amplitude; integrator saturation; limit cycle behavior; linear methods; stability analysis; system parameters; transients; Circuit stability; Computer science; Delta modulation; Digital filters; Digital modulation; Gain; Noise shaping; Nonlinear systems; Stability analysis; Transfer functions;
Conference_Titel :
Circuits and Systems, 1993., ISCAS '93, 1993 IEEE International Symposium on
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-1281-3
DOI :
10.1109/ISCAS.1993.393984
