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Amplifier board debugging notes (view source)
Revision as of 01:39, 29 September 2010
, 01:39, 29 September 2010→Thermistor/resistor tolerance
* Non implemented on prototype board. Suggestion: review whether this tolerance is sufficient at operating temperatures.
* Non implemented on prototype board. Suggestion: review whether this tolerance is sufficient at operating temperatures.
* '''consideration of the revision and modifications of the PCB layout are pending'''
* '''consideration of the revision and modifications of the PCB layout are pending'''
=== Update ===
Readout and interpretation of the temperature from this circuit results in about 5degC error! Interpretation:
* 5% tolerance may contribute a few degrees (though replacing with 1% 100k resistor didn't move the accuracy significantly)
* There is an ambiguity in the B parameter for this NTC thermistor: the table given in the manual does not seem to agree with the stated value of B of this device. However, this effects the reading on the scale of a 0.1deg
* few mV drop in the voltage may be occurring between the thermistor pin and ADC chip. Path resistance can be calculated and taken into account. (Significance to be verified)