On 07/02/2013 05:45 PM, Alexandre Belloni wrote: > On 02/07/2013 17:21, Lars-Peter Clausen wrote: >>>> >>>> I was looking at that yesterday as I had to had a scale for the >>>> temperature sensors. You'll have to be careful because the maximum >>>> measured voltage when DIVIDE_BY_TWO is not set is 1.85V and when it is >>>> set, it becomes VDDIO - 50mv. >> >> I had a quick peak at the datasheet and I think that's a typo. VDDIO is 3.3V. >> This sentence also doesn't make much sense if divide by two would actually >> lower the range. "For input channels (other than BATT, 5V, or VDDIO) with >> signals larger than 1.85 V, the divide-by-two option should be set." >> > > Yeah, what I think they meant is if !DIVIDE_BY_TWO : Vmax = 1.85V else > Vmax = 3.25V. So it may not be as easy as multiplying hte scale by two. > I couldn't test it, so I didn't implement it. Parse error on my side, in the datasheet it is a hyphen not a minus, so I though the sentence meant that the maximum is 50mV. I guess it is still a divide by two, but since the max input voltage is 3.3V you simply can't max out the ADC anymore since the maximum value corresponds to 3.7V -Lars -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
