| abstract |
A pipelined continuous-time (CT) sigma-delta modulators (SDM) is provided that has an architecture that is readily calibrated. The system includes a digital filter and other features that can be adjusted to account for input imbalance errors and well as quantization leakage noise. An example two-stage pipeline arrangement has CT SDMs (or sub-CT SDMs) 202 and 212, DAC 204, digital filter 206, amplifiers 220 and 210, digital gain circuit 214, summing circuits 208 and 216, output circuit 218, and an adjustable delay 222. CT SDM 202 may be a lower order modulator (i.e., order of 1 or 2), while CT SDM 212 may be a higher order modulator (i.e., order greater than 3) with aggressive noise shaping. Amplifier 210 also includes a filter. |