Lpc2000

Hi Owen,

I was just looking into this myself.  There is a FAQ on the Philips 
site (http://www-us16.semiconductors.com/cgi-bin/faq/faq.pl?
query=q&id=307&gid=36&fid=3) that says:

Q: On the LPC2xxx, the analog power pin (V3A) states that it should 
be nominally the same as the V3 pin, but can I connect a precision 
reference to this V3A pin that is at less voltage than the V3 pin or 
am I forced to use the same 3.3V power supply that I use on V3?  

A: The ADC voltage can go below 3V. According to test, the ADC 
operates according to spec even below 2V. 

Regards,


Tom

--- In lpc2000@yahoogroups.com, Owen Mooney <ojm@s...> wrote:
> Has anyone experience with lower A/D reference voltages on the 
LPC2138?
> 
> I usually use a 2.5V reference on 3.3v systems but the doc suggests 
that 
> this should the same as the main supply and
> the data sheet says that this should be 3 to 3.6 volts.
> 
> Owen Mooney