The merlin project. :)

[Tony Clark]

> >   How exactly do you plan to get 3V out when your battery is down to 
> >that level?  Now utilizing an LM4040 buffered through an op-amp will 
> >allow you to get down to less than 4V before the reference starts losing 
> >it and that's pretty good if you ask me.
> 
> What I did find was an LM336. Which is a 2.5 volt reference diode. A similar
> type of thing to the 4040 except it has an adjustment pin.

   Yup, we used these up until we 'discovered' the LM4040's.  They're 
decent enough.  You could still use this and put it though a 1.2 gain amp 
to get your 3V.  :)  It'd probably be more stable than what you were 
experiencing with the 4250's (which I have no experience with, BTW).

> I don't want to use a second reference and op-amp as I'm running out of
> board space as it is. But I have a couple of other trix to try out. Unless
> Paul P comes up with a couple of these 3 volt regs he was talking about.
> Which would save me a hell of a lot of board space I guess. :)

   Couldn't you just use an extra op-amp utilizing gain or reduction to 
get what you want out of the original reference?

> But I
> certainly can't get them down here. Last time I tried, I couldn't even get a
> zener below 5.1 volts. The kid in the shop tried to tell me that they
> couldn't make zeners lower than that. He suggested that it was physically
> impossible. Yea right!

   That's pretty sad.  I'm sitting on a pile of 3.6V zeners...
 
> Thanks for all the suggestions so far. I don't know what I'd do without you
> guys. I'll keep at it.

   Sounds like you'll get it solved soon.  :)  Keep us posted!

   Tony

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I can't drive (my Moog) 55!        |     The E-Music DIY Archive
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Tony Clark -- clark at andrews.edu    | aupe.phys.andrews.edu/diy_archive
http://aupe.phys.andrews.edu/~clark|     Contributions welcomed!
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