If you chose the DS89C420 for performance then Cygnal is probably your best choice. Although a chip would cost more than twice as much, it comes loaded with lots of good peripherals. It is a 3V part, with 5V tolent I/O. The DS89C420 is pretty limited with only 16k flash and there are no micros like it in Dallas's lineup.

I am about to start laying out the PCB for an electronics laboratory A/D - D/A board. The more I look at the Cygnal parts, the more I think I should scrap my design and go with it instead of the DS89C420. I bet Michael would like that. He probably gets a check from Cygnal for every person that switches over.

- Lee