1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Interface NTC thermistor with microprocessor

  1. Jan 7, 2015 #1
    1. The problem statement, all variables and given/known data
    A microcontroller for temperature limit control has a 0 V to 5 V
    power supply. An NTC temperature sensor provides an input voltage
    to a ・} 5 V comparator op-amp. Depending upon whether the
    temperature is below or above the set limit, the output from the opamp
    comparator will be low or high. It is undesirable for a direct
    electrical connection to exist between the sensor and the controller.
    Draw a circuit diagram to show how you could interface the NTC
    sensor to the microcontroller. Resistor values are not required.

    2. Relevant equations
    N/A

    3. The attempt at a solution
    I have a diagram of a window comparator circuit (see attached) with the thermistors output being one of the opamp inputs. I think I could use a optics to transfer the signal from the comparator to the microprocessor. I was thinking of a LED to transmit the signal and a photodiode to receive it at the microprocessor, but I'm unsure how to draw this. Any help would be greatly appreciated. Window Comparator.gif
     
  2. jcsd
  3. Jan 7, 2015 #2

    gneill

    User Avatar

    Staff: Mentor

    Do a web search on "optocouplers". You may get some ideas.
     
  4. Jan 8, 2015 #3
    Yeah thanks I got some help from my buddy, just wanted to make sure I was drawing the components correctly. Never been great with electrical circuits.
    Thanks for the reply.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Interface NTC thermistor with microprocessor
  1. Interfaces and waves (Replies: 0)

  2. Thermistor buying (Replies: 1)

Loading...