A Second-Order Sigma-Delta Modulator with a Gain Scaling of ADC and a Simple Multibit DAC

摘要

A second-order sigma-delta modulator with a 3-bit internal quantizer featuring a gain scaling of an internal ADC and a very simple internal DAC has been designed and im- plemented in a 0.8μm double-poly double-metal CMOS process. We improved the performance of the modulator with the gain scaling of a 3-bit internal ADC and design of the internal error- free DAC with using simple logic gates.