AVR-Chat

You can do it cheaply by using two of the non inverting hex buffers 
and pull up resistors. The sn74lvc1g07 is a single gate, runs on 
3vdc and has open drain. depends on how many signals you have to 
translate. For something like SPI signals across the two nodes you 
could use the low voltage version of the hex open drain buffer and 
the standard ttl on the other side with pull ups. I think Maxim Semi 
makes a single part for both sides of the fence but they cost more.

Al Welch

--- In AVR-Chat@yahoogroups.com, Mike Murphree <mike@t...> wrote:
> 
> On Jan 16, 2005, at 10:40 PM, DG (dee-gee) wrote:
> 
> >
> >
> > I have similar design. I'm using SN74LVTH244 to interface Atmel 
5V
> > part to 3.3V comm device.
> 
> Another useful characteristic of these BiCMOS family parts is that 
they 
> can be attached to a live bus while powered off without any ill 
> effects.  They do not contain the standard ESD diode to the 
positive 
> rail and remain high impedance even when off.  ABT parts are in 
the 
> same family as these.
> 
> Mike