[sdiy] Static ADC and DAC recommendations?

[MTG]

That's successive approximation. Flash uses a massive pile of 
comparators and a priority encoder.  I'm sure all the old ones even had 
a clock, if only for operating the output latch. Maybe you can find one 
that allows for transparent mode when the LE* signal is low?  Anyway, a 
sufficiently fast clock would be indistinguishable from asynchronous if 
you're clever.

GB