Pipelined sigma-delta modulators with interstage scaling

A family of sigma-delta converters that utilize noise shaping in conjunction with pipelined architecture and interstage scaling is proposed. The converters consist of pipelined stages each consisting of a sigma-delta modulator and a quantizer external to the loop. A two-stage pipeline utilizing single-bit, first-order sigma-delta modulators and four-bit quantizers has been implemented in silicon.