Temperature measuring equipment, module and method based on thermistor

Abstract

The invention provides temperature measuring equipment, a temperature measuring module and a temperature measuring method based on a thermistor. A reference resistor and the thermistor are arranged inseries to supply power, and when the thermistor is at a reference temperature, voltage values at two ends of the reference resistor and voltage values at two ends of the thermistor are measured; whenthe thermistor is at a target temperature, voltage values at two ends of the reference resistor and voltage values at two ends of the thermistor are measured; a specific value expression between a target thermosensitive resistance value and a reference thermosensitive resistance value of the thermistor is deduced, a corresponding position in the expression is described by substituting resistancevalue-temperature characteristics of the thermistor into the expression to obtain a final expression of the target temperature. According to the application, the reference voltage is collected in realtime by utilizing a voltage division principle, so that the influence of voltage source fluctuation is reduced, the actual resistance value of the thermistor does not need to be calculated, an intermediate variable is used for temperature calculation, the influence of reference resistance error is eliminated, and data transmission between equipment is facilitated.

Description

Technical field [0001] The present application relates to the technical field of temperature detection, in particular to a temperature measurement device based on thermistor, and also to a temperature measurement module based on the thermistor, and a temperature measurement method based on the thermistor. Background technique [0002] The thermistor is a temperature sensitive element that uses metal oxide or semiconductor material as the resistor body. Among them, the negative temperature coefficient thermistor (NTC) has the characteristics of large resistance, high sensitivity, good stability, and easy production. Widely used temperature measuring equipment. The resistance-temperature characteristic of the thermistor can be described as formula (1). [0003] [0004] Among them, B is the thermal sensitivity index, which is determined by the physical properties of the material and can be regarded as a fixed constant. R T Can be obtained directly through the temperature measuremen...

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Problems solved by technology

[0005] In the prior art, the temperature measurement module design based on NTC mainly includes: 1) module design based on constant current source (such as figure 1 ), the current I flowing through the NTC is constant, R ntc =U 1 / I, but the constant current source module is generally larger in size and higher in price, so the application is relatively limited; 2) The temperature measurement module design based on the constant voltage source (such as figure 2 ), R ntc =R ref wxya 1 / (U 2 -U 1 ), because the constant voltage module is relatively small in size and low in price, so it is widely used, but it is easily affected by the reference resistance R ref The manufacturing error and the power fluctuation of the constant voltage source U2 lead to a decrease in temperature measurement accuracy and even errors

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