What thermistor is on the PIC-MAXI-WEB?

Started by toozie21, March 13, 2014, 01:53:47 am

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toozie21

I am looking to pick up the PIC-MAXI-WEB, but I can't figure out what thermistor is on there (I want to make sure it will work for my application).  The schematic doesn't call out a part number for me to look up a datasheet for.  Does anyone know what part that is?

LubOlimex

It is NTC103 10k. The B parameter is 4100.

There is plenty of info about such thermistors if you search the web. The part of the code responsible for the measurement is the blow one:

HTTPPrint_temp(void)

...
   
    r = ((1024.0*10000.0)/(float)tmp)-10000.0;
    // B parameter equation - B = 4100
    temperature = 4100.0/log(r/0.0111182) - 273.15;

    itoa(temperature, TempString);

...
}


We had to improvise with the B parameter equation a bit (http://en.wikipedia.org/wiki/Thermistor) because the board was using too much memory initially.

Best regards,
Lub/OLIMEX
Technical support and documentation manager at Olimex

toozie21