The thermistor probe was from a previous design. Ithink it was from Alpha
or something like that.  It met that precision.  I don't know how they did
get that precision. No per unit calibration was required on our end. I
think we used a .1% resistor and 20 bit ADC.

Harold
> Hello Harold
> I looked a the accuracy line of thermistors... They appear to be accurate
> to maybe 1%.
> Did you calibrate each unit to make it good to +/- 0.1 degree (C or F) ?
> Best
> Gus
>
>
>> On Mar 28, 2013, at 9:16 PM, Harold Hallikainen wrote:
>>
>> I believe it's +/- 0.1 degree (C or F)
>>
>> Harold
>>
>>
>>> Thanks Harold
>>> I looked at the unit and could not determine the accuracy of the unit..
>>> Gus
>>>
>>>> On Mar 27, 2013, at 9:11 PM, Harold Hallikainen wrote:
>>>>
>>>> I used a precision thermistor, a precision resistor and (as I recall)
>>>> a
>>>> 20
>>>> bit delta sigma ADC in this thermometer: http://www.gla-ag.com/ .
>>>> Since
>>>> the supply to the top of the resistor was also the ADC reference, a
>>>> precision reference was not required. Linearization is done with a
>>>> table
>>>> and linear interpolation.
>>>>
>>>> Harold
>>>>
>>>>
>>
>
>
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