On digit-recurrence division implementations for field programmable gate arrays

The flexibility of field programmable gate arrays (FPGAs) can provide arithmetic-intensive programs with the benefits of custom hardware but without the high cost of custom silicon implementations. Efficient mappings are key to fast arithmetic implementations on FPGAs. A process for developing such mappings with lookup table based FPGAs is explored. The development process is illustrated with SRT division and the Xilinx XC4010 FPGA. With this mapping process a linear sequential array design that avoids the common problem of large fanout delay in the critical path is created. This approach has a cycle time that is independent of precision, yet it requires approximately the same number of logic blocks as a conventional implementation.