Adapting sensors to an Arduino. This is a hands-on workshop.
Silicon diodes have a handy feature. Using a constant current, the voltage drop across a forward biased silicon diode drops by about 2mV per degree Celsius and are good over a wide range from cryogenic temperatures to around 200 to 250C.
However, that is on an offset voltage of about 600mV at room temperature, and only covers about 200mV from 0 to 100C. With an Arduino Uno analog input mapped from 0-5V a 1024 bits, that is about 4.9mV per bit, which is about 2.5C per bit, or only about 41 bits of resolution from 0 to 100C!
We'll use an Op Amp to remove the offset and amplify the signal to match an Uno or Nano's input. Or with one resistor change, any other Arduino.
There is a $5 charge for Nonmembers, free for members in good standing of OlyMEGA. A kit of parts will be available for an additional charge if you wish to build along, protoboard (white plug in board) extra.
Many other sensors have an offset and a small output signal. Gas detectors, strain gauges, etc. With minor changes, this same circuit can adapt their output to get the best resolution.
An Arduino is required if you wish to put this to the test. OlyMEGA has Unos available for purchase. We will be programming Arduinos to read and display at the next workshop.
I strongly recommend downloading the PDF of the 2nd edition of Op Amps for Everyone:
Or buy the latest 4th edition on Amazon. Don't forget to go to the OlyMEGA page first and click on the Amazon Associate link, then OlyMEGA gets 4% while you pay the same price.
Please join the OlyMEGA forum to help me choose a project or projects that will be offered at a later session.