is there an IC that will help in regulating multiple i/o lines, in one IC package? I'd like to step down 8 to 16 5v i/o lines, down to 3.3v. I know of IC packages that do this for one line, or i could just resistors on each line... but I'm curious if there is a way to do several lines with less components.
I would just use a resistor network/array which you can get in 2 to 36 resistors in each packet.
The CD4049 (inverting) and and CD4050 (non-inverting) hex buffers have inputs that are over-voltage protected. They were designed to step down signals from higher-voltage logic back in the days when TTL walked the Earth.
There are large numbers of chips aimed at doing this sort of "level translation."
See here for instance: http://focus.ti.com/logic/docs/translationselection.tsp?sectionId=458
awesome. thanks for all the links. i will use these suggestions as a guideline for my next project