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Author Topic: Using analog reference for PTC readout  (Read 159 times)
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Hi,

Im trying to read several PTC1000 Sensors using the Arduino due.

Im supplying 3.0V to the circuit using the ADP150AUJZ, the VDD of the Due is 3.3V.

To get an even higher accuracy I could supply the 3.0V to AREF.. Is this correct?


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Technically, you would be getting slightly better "precision" (slightly smaller voltage steps) rather than better accuracy, but, yes.
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Thanks! Do you think there is anything to improve on this circuit?

U2 creates the reference Voltage (3V) which is also supplied to the Analog Ref pin.

R1 and R2 is a Voltage devider (PT1000 and R2 2k) to measure the voltage over a short Distance (maybe 2 meter).

R6 and D1 is an overvoltage protection ( ESD and general overvoltage protection (I didnt calculate the maximum voltages/currents yet smiley-grin)

The Opamp has a gain of 2 which delivers an output voltage of 0-3V



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Do you think there is anything to improve on this circuit?

I'm not an electronics engineer but the circuit look reasonable to me.
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