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Last Post 24 Aug 2015 10:50 PM by  Adam Ford
R62 Between 5GND and DGND
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Rodney Wong
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19 Aug 2015 05:05 PM

    Why is there a 0.05Ohm resistor between 5GND and DGND? This can be seen on page 8 of the eXperimenter kit.

    Adam Ford
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    20 Aug 2015 10:13 AM
    I talked to two other engineers here, and the small resistor is for sensing current by measuring the voltage drop across it.

    The other option to measure current would be to remove the resistor, and place a current meter across J18.

    If you don't care about measuring current, a 0 ohm resistor could work, or tie the ground on the jack directly to DGND.

    adam
    Rodney Wong
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    24 Aug 2015 08:20 PM
    Hi Adam,

    How would we use the resistor to measure current? Would we use the resistor with the battery fuel gauge? Or does the SOM handle the measuring with something like a A/D?

    - RW
    Adam Ford
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    24 Aug 2015 10:50 PM
    Using that resistor, you can measure current taking the voltage measured across the resistor and dividing it by the resistor value.

    I = V/0.05

    You'd had to use a volt meter.

    adam
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