Patent attributes
A pipeline ADC architecture with suitable feedback can implement noise shaping. By feeding back the residue generated by the last residue generating stage to selected locations in the pipeline ADC, the delays in a pipeline ADC can create a finite impulse response (FIR) filtered version of the quantization error. The FIR filtered quantization error is added to the signal and evaluated by the pipeline ADC, which results in spectral shaping of the quantization noise. Unlike a conventional pipeline ADC, the output of the backend stage is scaled and filtered by a noise transfer function (NTF) of the residue generating stages prior to combining the output with other outputs of the pipeline ADC. The processing of the shaped quantization noise by the backend stage results in further noise suppression.
