"Timothy L. Nali" writes:
For a class project, I will be designing a VLSI cmos chip to generate truly random numbers (The chip will be fabricated). I'm limited to a 2-micron standard cmos technology
The most promising design I've seen so far (that I can actually do) is based on clocking a D flip-flop in the following way:
I'd say that the design you have picked has a couple of problems with it. The first is that you are, from what I can tell, building a synchronizer, which means that you may have metastability problems. (Your diagram wasn't completely clear so I can't tell). Also, you are depending on a sloppy clock and a not sloppy clock actually having the stated properties, which means you aren't really generating randomness so much as hoping you can detect and exploit it. As it is very hard to determine if a stream is really random, this makes your life difficult. Far better to try to use some analog tricks in the circuit itself to generate the random numbers for you. Of course, some of these end up producing metastability problems of their own... Can anyone point this guy at good texts on all of this? I've never found one... Perry