Sigma-delta analog to digital converter architecture based upon a modulator design employing a mirrored integrator
We present a method to increase the resolution and stability of /spl Sigma//spl Delta/ analog to digital converters in which the entire /spl Sigma//spl Delta/ modulator is enclosed in a chopper-stabilization (CHS) structure. Simulations of the proposed architecture show that the effects of integrator opamp non-idealities (1/f noise, DC offset and drift) and digital-to-analog converter (DAC) DC offset and even-order distortion harmonics are eliminated and that the effect of integrator saturation distortion is reduced by up to 27dB in comparison to existing designs. Finally, the proposed architecture may be realized in a single-ended design enabling area-conservative circuit layouts.