What's the lowest ADC reference voltage I can use for the LPC1114 ?

[lpcware]

Content originally posted in LPCWare by UncleJoe on Sun Jun 22 15:01:15 MST 2014
I'm wondering if I can directly measure the heart's  ECG with a micro controller.

I need very high accuracy (in the sub mV range), but very low bandwidth. I've tried putting together a circuit with the ADC voltage reference (VDDA) set to 0.1V, but no matter what, my ADC readings are always 1023.

I don't see the minimum reference voltage mentioned in the documentation. Is there one?

[lpcware]

Content originally posted in LPCWare by nxp_apps on Thu Jul 03 15:40:15 MST 2014
Hi,

On the LPC1114, the VDD supply is internally tied to the ADC internal reference voltage and analog supply.
Thanks.

nxp_support

[lpcware]

Content originally posted in LPCWare by LabRat on Sun Jun 22 16:00:51 MST 2014
VDDA is not Voltage Reference  :exmark:

Use a microcontroller with Voltage reference Input   :)

Something like LPC15xx with VREFP_ADC pin (and fast 12bit Converter) ...