There is a serious non-linear relationship between the resistance value and temperature of NTC thermistor. If the thermistor is sampled directly without linear treatment, it will result in poor resolution of high/low temperature sampling. So in practical use, it is necessary to make effective linear compensation for the non-linearity of NTC thermistor. Common solutions are Bridge Linear Method, Constant Current Source or Constant Voltage Source Measured Method, Amplifier Compensated Method, Timing Circuit Method and so on. The linearization effect of Bridge Linear Method is obvious, the circuit is simple, the anti-jamming ability is strong, but the measured accuracy is not high, it’s usually used in the case where the precision of temperature measurement is not high. Constant Current Source or Constant Voltage Source Measured Method can easily realize the conversion of resistance to voltage signal, but they need to add additional single chip microcomputer and its related software to solve its nonlinear problem, which will make the complexity of the circuit become higher, at the same time, it will also put forward strict requirements for the stability of the constant current source, constant voltage source.
In short, the traditional NTC linearization method is either worse degree of linearization, or the circuit is complex and cause higher cost. Therefore, a simple and efficient NTC thermistor linearization technology can achieve linear compensation for thermistor, thus facilitating the debugging and optimization of the circuit.