IMPLEMENTATION APPROACHES IN THE COMPUTER-AIDED DESIGN OF CSD DIGITAL FILTERS

Abstract

The implementation phase in the Computer-Aided Design (CAD) of Canonical- Signed Digit (CSD) digital filters is time consuming. Although the procedure is well defined and documented, the work is tedious and is suitable for automation. This thesis discusses a software and a hardware approach for automating the implementation phase of infinite impulse response digital filters realized by cascading second-order sections. In the software approach, a FORTRAN program has been developed to generate the assembly language code for the implementation of the CSD digital filter on specific microprocessors. Once the designer specifies the desired microprocessor and the name of the input file containing the filter information to produce the desired filter response, the code is automatically generated. Currently the program is capable of generating codes for single section digital filters on Intel 8086, Motorola 68000, and Texas Instruments TMS32010 processors. In the hardware approach, a cell library has been developed as the first step towards the automation of the generation of Very Large Scale Integrated (VLSI) layout for the CSD digital filters. Currently the cells have been used to hand-craft the designs of CSD digital filter elements, however, consideration has been given to the design of library so that the cells may be integrated with a Silicon Compiler.