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Reply To: Voltage divider on multipurpose screw adapter

Home › Forums › Mayfly Data Logger › Voltage divider on multipurpose screw adapter › Reply To: Voltage divider on multipurpose screw adapter

2022-01-12 at 5:20 PM #16254
Matt Barney
Participant

    After probing the screw term adapter, I don’t think that it will work for my purposes as I described above. If I’m correct, the way the adapter’s voltage divider works is this: When the S1 jumper is set to Res-Div and two matched resistors are installed on the S1 side of the adapter, the voltage output on the Grove’s D1 pin will be half of the voltage input to screw terminal S1, with Gnd as reference.

    However, because my sensor’s output is referenced to its Signal Ground lead, not its Supply Ground, I need to use the ADC’s differential, rather than single-ended, signaling capability. Because of the way the screw terminal adapter maps the output and ground pins, I don’t believe I can use its resister-divider capability for differential signals. Any suggestions? @shicks?

    For reference, the sensor’s wiring guide is here: http://docs.turnerdesigns.com/t2/doc/manuals/998-2188.pdf

    Thanks,

    Matt