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Range and resolution of ADC readings on BGS5T | Thales IoT Developer Community

December 2, 2015 - 12:17pm, 2527 views


After reading the BGS5T documentation, I am confused about the resolution of the ADC1_IN signal.  Each document appears to give different values for the resolution of the ADC.  For example:

Document                                    Page       Section                             ADC resolution

Hardware Description            46              4.2.4                                 0 - 5V in 1024 steps

AT Command Set                      387          19.5                                    0 - 1200mV       (using at^sradc)

Javadoc                                         class      -25 - 2425mV   (using ADC.getValue() )

Which is the correct resolution?   If the Hardware Document specifies that the ADC accepts an input up to 5V, why does the AT command at^sradc only return readings up to 1200mV?  And why does class return negative voltages and positive readings only up to 2425mV?

I'm assuming I have to apply a conversion factor in each case, but it would be helpful to have an explanation of why these different ranges are provided.  Thank you.