The high-precision measurement of temperature in platinum resistance is introduced

its research covers two aspects

such as the hardware circuit and curve fitting.In hardware circuits sensor constant current drive circuit and A/D converter circuit use the same voltage as a reference voltage

so it guarantees the temperature measurement accuracy.In curve fitting

it fits the curve which describes the relations of sampling value-temperature by using least squares method

It compensates the deviation which occurs in each middle part of the signal from platinum resistance to the A/D conversion in the temperature measurement of Pt100.This method can make measurement error superior to 0.05℃

and now it applies to the development of high-precision temperature thermal control system.