Digital compensation of memory errors in passive Sigma-Delta modulators employing FIR filter

This paper propose a finite impulse response filter for compensation method to improve resolution of passivediscrete-time sigma-delta modulators. The passive integrator transfer function leading to gain and phase errors,degenerates the modulator performance because of signal attenuation in modulator loop. The error of passiveintegrator is modeled as an output-referred model and Finite Impulse Response filter is employed for compensation.The method is applied to the first and second order passive sigma-delta modulator to achieve low-power and highresolution. Result of simulation demonstrated that the gain and phase errors compensation by the method is effective.

Keywords:

Analog to digital converter (ADC) , Digital compensation , Finite impulse response filter , Passive sigma-delta