Timing exact design conversions from an original field programmable device
to an application specific device is disclosed. In a first aspect, a
design conversion from a field programmable gate array (FPGA) to an
application specific integrated circuit (ASIC) comprises a user
configurable element in the FPGA replaced by a mask configurable element
in the ASIC. In a second aspect, an FPGA design conversion to an ASIC
comprises converting a user configurable memory bit pattern generated by
a software tool to program the programmable content of the FPGA to a
hard-wired metal pattern for the ASIC.