[sdiy] Another new hard to find part....

[Roy J. Tellason]

On Tuesday 06 July 2004 12:13 pm, Scott Gravenhorst wrote:

> >> Not only will CD4xxxx work to 15 volts (some parts to 18), they will
> >> also work down to 3 volts.
> >
> >True,  though this isn't an area where I've taken advantage of it yet.
> >
> >> I have run several CD4xxxx based circuits from +/- 8 volts without
> >> problems. I just make sure all of the parts in the design are speced to
> >> 18 volts.
> >
> >What's that,  the "B" series?

> "B" at the end of the number just means "buffered".

No,  I have the original RCA databooks on those parts.  The "A" series was 
only rated to go to 15 volts,  while the "B" series went to 18 -- but that's 
an "absolute maximum rating" and you don't usually want to go there,  quite.

The only reference I've seen to buffering is the "U" on the end of the part 
number before the A or B,  and that only on the 4069UB for some reason.

> You can only know the voltage range by getting the data sheet.  I have a
> habit of downloading the PDF files for everything I use and keeping them
> here.  "UB" at the end means unbuffered and have some interesting uses. 
> Eg., the 4069UB can be used as a "linear amplifier" (see data sheet) which
> works kind of like an opamp.  It has an interesting was of distorting, more
> like vacuum tube soft clipping.

Now I remember *that* one from Craig Anderton's book.  :-)

Don Lancaster also talked about using these parts in linear mode as well, and 
you can make some mighty simple oscillators if the requirements aren't 
critical -- a couple of inverters,  one cap,  and one resistor,  if I'm 
remebering right.  (I've gotten into this nasty habit lately of not bothering 
to remember much,  figuring I can refer to the book if need be.  :-)

Got any particularly good sources for data sheets and app notes?  I'm familiar 
with Dial,  but they have an awful lot of gaps in there and there was one 
other I hit recently,  but I can't recall where it was offhand.