This paper firstly introduces the characteristics and PT100 platinum resistance temperature measurement method, on the basis of PT100 is presented based on the temperature measuring system design. In this design, is PT100 platinum resistance as A temperature sensor, the constant current temperature measurement method, through the single-chip microcomputer control, with an amplifier, A/D converter to temperature signal collection. In addition, also designed the LED digital display circuit tube, can realize to the temperature of the display. This design USES the three wire platinum resistance temperature measurement circuit, through to the circuit design, reduce the measurement circuit and PT100 own error, make the temperature control precision in 0 ℃ ~ 100 ℃ to + /-0.5 ℃ scope.
This paper using MSP430 microcontroller, operational amplifiers, platinum resistance PT100 and three of digital tube system, write the corresponding software program, so that to realize the temperature of the display. The characteristics of the system is easy to use; Measurement precision, stability and reliable; Measurement range; Use object wide, after revising application will more extensive