Do some measures with arduino

hi,

I'm measuring some DC voltages with my multimeter. But now i would like to pass that values to the computer. I'm thinking to buy an Arduino Uno to do that, but my signal is really low (from 30 mV to 100 mV). I need to measure 6 of these values simultaneously. It is possible to do that with Arduino ?

thank you

You have only one A/D converter, so simultaneous readings are impossible on an Uno. Readings are normally around 100us apart. This may or may not be a problem for you.

So what you are saying is that it’s impossible to measure 6 DC voltage signals of 35 mV each using the 6 analog input pins of the board ?

fmrp89: So what you are saying is that it's impossible to measure 6 DC voltage signals of 35 mV each using the 6 analog input pins of the board ?

No, AWOL is saying that without extra hardware it's impossible to read six inputs [u]simultaneously[/u]. The closest you could get would be to take six readings about 100 uS apart. Is that close enough to 'simultaneous' for you?

No, I'm not saying it is impossible to perform six readings, I am saying it is impossible to do it simultaneously without additional hardware. With a 1.1V reference, your resolution would be around 1.07mV.

You could get 6 x ADC chips which use I2C or SPI, and get them to start reading for you. The SPI one I used a while back did a reading every couple of microseconds.

You can configure the ADC converter on the Uno to run faster at some sacrifice to precision (change the prescsaler). You can double the conversion time and only lose one bit of precision, from memory.