Overload analysis of continuous time sigma delta modulators

Abstract

When a continuous time sigma delta modulator (CT ΣΔM) is overloaded, its output signal to quantization noise ratio (SQNR) decreases when the ΣΔM's input power is increased over a certain value. In this paper, the range of quantizer gains that cause a CT ΣΔM to overload is determined, and this range of values is used to determine the maximum input signal power that prevents overload. To validate the predicted maximum input power that prevents overload, 2nd through 5th order CT ΣΔMs are simulated.