The subject invention concerns novel analogs of fentanyl opioids. At each sequence an image is displayed representing the discrimination of the contributions of the particles of the body as a function of their time T2 compared with this effective time. A nitrogen anneal step is subsequently performed to completely convert the rich nitrogen containing polysilicon residue into silicon nitride that can eliminate the conductivity of the polysilicon residue and prevent conventional oxygen encroachment occurring. The one or more divide-add circuit units is configured to be each composed only of capacitors and switches and to generate a final DA conversion output for the entire input digital code based on the voltages of the DAC units.