Re: AW: [avr-gcc-list] accuracy of internal 2.56V reference

[Joerg Wunsch]

"Haase Bjoern (PT-BEU/EMT) *" <address@hidden> wrote:

> I think you will have too look at the datasheet of your specific
> device and your specific mask revision :-). IIRC, the voltage
> references are fairly unstable.

That's not true.  You confuse stability with accuracy.

They aren't very accurate (i.e. they can vary quite a bit from the
nominal voltage as shipped), but their stability (vs. temperature and
Vcc drift) isn't all that bad.

Bottom line, if you can calibrate the initial deviation somehow (e.g.
by storing the exact value in EEPROM during `burn-in'), it might be an
option.  After all, it safes you some external parts.

The OP didn't really mention what his term `accuracy' actually refers
to.

> BTW: This IMHO, this is not a topic for this list.

It would be more appropriate for avr-chat, yes.

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)