Operator's Manual
MercuryiTC
©2014 Oxford Instruments
Rsensor = Rref x | ADCnorm
is the reference resistance (either 2 kohms or 80 kohms).
is the ADC reading, normalised to the range
is the interpolated gain from the calibration tables.
is the gain setting of the ADC.
The measurement accuracy of this circuit does not depend on the accuracy of the excitation
current or the reference voltage. The accuracy prim
reference resistor plus any errors introduced by operational amplifiers.
Constant voltage measurement mode is used with sensors that have a negative temperature
The sensor and a reference resistor (either R44 or R45) are connected in series. Digital to
analogue converters U24 and U25 generate an upper and lower demand voltage. The upper
voltage is buffered by U10 and applied to the upper end of the sensor resistor
is the reference resistance (either 2 kohms or 80 kohms).
is the ADC reading, normalised to the range
is the interpolated gain from the calibration tables.
is the gain setting of the ADC.
The measurement accuracy of this circuit does not depend on the accuracy of the excitation
current or the reference voltage. The accuracy prim
arily depends on the accuracy of the
reference resistor plus any errors introduced by operational amplifiers.
Constant voltage measurement mode is used with sensors that have a negative temperature
The sensor and a reference resistor (either R44 or R45) are connected in series. Digital to
analogue converters U24 and U25 generate an upper and lower demand voltage. The upper
voltage is buffered by U10 and applied to the upper end of the sensor resistor
The measurement accuracy of this circuit does not depend on the accuracy of the excitation
arily depends on the accuracy of the
Constant voltage measurement mode is used with sensors that have a negative temperature
The sensor and a reference resistor (either R44 or R45) are connected in series. Digital to
analogue converters U24 and U25 generate an upper and lower demand voltage. The upper
voltage is buffered by U10 and applied to the upper end of the sensor resistor