ADC on LPC1768

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by paulantony49 on Tue Dec 30 04:37:11 MST 2014
I am using the 12bit ADC of the LPC1768 for sensor data accusation and naturally require very high reliability. On testing the same using a LPC1768 xplorer board, the results shows that there is a chance of error in every bit. On taking 8000 samples the following probability of error was observed.
err_pb = 0.0135    0.0265    0.0300    0.0289    0.0296    0.0331    0.0441    0.1571    0.1734    0.2404    0.4808    0.4325

The error in the last two bit is understandable (ground noise), but i am puzzled by the error in the higher bits. I tried it on both burst mode and the software controlled mode, with different frequencies of conversion. Still the error in the higher bit remains.

I would be grateful if someone could advice me on the source of error, whether the problem is only for LPC1768 xplorer or LPC1768 or in the programing.