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Thread: Teensy 3.6 - 0.5-4.5V Sensor input - GND or AGND

  1. #1
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    Teensy 3.6 - 0.5-4.5V Sensor input - GND or AGND

    hi @all,

    i'm not sure if i should use gnd or agnd and if so where ?

    thx for hint
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  2. #2
    Senior Member+ Theremingenieur's Avatar
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    Use GND. Your signal looks already filtered enough.

  3. #3
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    thx

    I had a mistake in the attached plan, is that right or is it too much ?Click image for larger version. 

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  4. #4
    Senior Member+ Theremingenieur's Avatar
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    Following the Kinetis application note, the source impedance should be relatively low for precise ADC readings. That’s why I’d suggest making the voltage divider 5k/10k instead of 10k/20k. And yes, this wiring variant looks much more efficient.

  5. #5
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    Thanks for the note, I'll go to 5k/10k.

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