Lm335 Sensor; Figure A.1 - Non Linearity Graph - Newport LDC-3706 Series User Manual

Figure A.1 – Non Linearity Graph
If a maximum absolute error of 0.8°C is tolerable (over the entire temperature range), the one
point calibration of C should be used. If C is calibrated at 25°C, and the intended operating
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range is 0 to 50°C, a maximum error of about ±0.2°C may be expected over that operating
range. If a greater accuracy is desired, the two point method of determining C and C should be
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used. Note however, the absolute error curve is non-linear; therefore, the constant C will vary
2
over different temperature ranges.

LM335 Sensor

The LM335 is a linear thermal sensor which acts as a constant voltage regulator. It produces a
voltage, V, which is directly proportional to absolute temperature, over its useful range (-40°C to
+100°C). This nominal value can be expressed as:
= 10
Where V is the nominal voltage produced by the LM335 and K is the temperature in Kelvin.
The LDC-3706 instruments use V to determine the nominal temperature, T , by the formula:
n
= − 273.15
10
Where T is measured in °C.
n
The temperature, T , which is displayed by the LDC-3706, is first calibrated as follows:
d
= + ∗
10
Where C and C are the constants stored by the user in the LDC-3706 for the LM335.
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December 2019 108 LDC-3706 Series Laser Controller