At 08:20 AM 11/18/02 +0000, you wrote:


>   You can then select what type of function to fit, linear,
>polynominal, exponential, log etc.  For a thermistor, a 3rd order or better
>polynominal does the job very well.  Under the "Options" tab of the trend
>line menu, check the "Display equation on chart".  You can then use this
>equation to obtain any arbitrary value.

You must be using the thermistor over a very narrow range, n'est pas?
(as opposed to the full usable range of the sensor)

I've found even high order polynomials a very poor way of doing R->T
conversion for thermistors. Breaking it into segments and using
a number of lower-order polynomials works, however.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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