Re: 3.3V-5V level ****fters

"Joerg" <notthisjoergsch@[EMAIL PROTECTED]
> wrote in message
news:v78Dk.1093$hc1.13@[EMAIL PROTECTED]
> Jim Thompson wrote:
> > On Wed, 24 Sep 2008 17:26:32 -0700, Joerg
> > <notthisjoergsch@[EMAIL PROTECTED]
> wrote:
> >
> >> What's the jelly-bean level ****fter du jour, the most popular?
> >>
> >> Need to ****ft three sigs 3.3V to 5V and another three 5V to 3.3V.
Stuff
> >> us analog dudes normally don't do. The TXB0104 looks ok, so does the
> >> 74LVC4245. But the specs for both are horrible, incomplete at best.
Not
> >> much in drive levels mentioned, or just for one direction.
> >>
> >> The topper is a comment in the TXB spec, "OE should be tied to GND
> >> through a pulldown resistor; the minimum value of the resistor is
> >> determined by the current-sourcing capability of the driver" That
driver
> >> is obviously on the chip. Duh! Of course they also forgot what to do
if
> >> not needed. Pull up? Leave open? Who knows. Well, maybe they had a
> >> kegger the night before ...
> >>
> >> Here's what seems to qualify as a datasheet these days:
> >> http://focus.ti.com/lit/ds/symlink/txb0104.pdf
> >>
> >> VOH and VOL at 20uA. Microamperes! Couldn't believe it.
> >
> > What's not to like about the 74LCX245?
> >
>
> Well, I am using the LVC4245 now. I like the two supplies on those, IOW
> a "real" level translator. Got to deal with power sequencing though.
>
> --
> Regards, Joerg
>
> http://www.analogconsultants.com/
>
> "gmail" domain blocked because of excessive spam.
> Use another domain or send PM.


T'other month did an 'X****t' network adaptor thing for a customer. I
couldn't be arsed ordering or waiting for translator chips, so used a
dozen
transistors instead. But I wasn't looking for 1nS switching :).
I'm happily using more and more of the these transistor things as time
goes
on, having had a belly full of I.C. stuff being obsoleted and the
disruption
it causes.
Assembly cost of discretes would have been a problem 5 years ago but it's
now all pick-n-place and I've yet to hear a peep of complaint from the
production company.
Ltspice to pick-n-place to customer. Ain't modern technology the bee's
knees.
Earning a crust is getting much, much easier :)