| This work presents the use of a new design methodology for the creation of analog integrated circuit components featuring optimization with Matlab and Simulink. This procedure allows circuit design to take place at the highest level of abstraction, and has the added advantage that designs can be implemented with currently used, and widely available tools. It results in building block requirements being specified prior to the undertaking of transistor level simulations, thereby saving much valued design time.;Also presented are the issues behind the design of an audio-band, single bit switched capacitor delta-sigma modulator with 16 bits of performance. This begins with the filtering function design, continues with the realization in a low voltage standard CMOS process, and concludes with experimental measurements to gauge performance. The creation of the modulator was carried out using the proposed top-down design methodology, and its experimental performance is used to help validate the procedure.;In addition, the design and fabrication of a multibit DeltaSigma modulator including a novel internal DAC was carried out. The multibit DAC is based on encoding DC levels into digital PDM bitstreams, which are then decoded by a single analog filter. The use of a single filtering path reduces mismatch effects in the DAC. The functionality, performance, and limitations are explored by examining the experimental results of a 2.5 V, audio-band, 2nd order, 3-bit DeltaSigma modulator in a 0.25 mum CMOS process. |
