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    NTC thermistors play a vital role in the home. Do you know how many common household appliances use NTC thermistors? Let's take common household appliances as an example to tell you.

    Detailed list of NTC thermistor usage in an ordinary urban household with three people (a total of 51)

    As can be seen from the above table, although NTC thermistors are not directly visible to the naked eye, they are indeed essential electronic components in the use of household appliances. So what is the conductive principle of NTC thermistors?

    Researchers tried to infer theoretically that transition metal oxides undergo structural changes due to doping, and the low-valence ions in the oxides make the oxides become p-type semiconductors. Later, after in-depth research, it was found that the conductive mode of this type of material is not the traditional semiconductor conductive mechanism of carrier movement in the full band. The direct cause of its conductivity is the direct transfer of electrons. This conductive mode is the currently recognized conductive mechanism of negative temperature coefficient NTC ceramic materials, which is technically called the hopping conductivity model theory.

    From the theory of hopping conduction model, we know that the conduction of NTC thermistor ceramics is neither caused by the movement of electrons in the conduction band nor the migration of holes in the valence band, but the result of direct transfer and transition of electrons between energy levels. It is the process of electrons jumping from one atom to another adjacent atom. The reason is that most transition metals are variable-valence metals, and the transition process of electrons is the valence change process of cations.

    From the conduction mechanism of the hopping conduction model theory, it is not difficult to conclude that the necessary conditions for the conduction of spinel-structured NTC thermistor ceramic materials are: first, the ceramic material must be an anti-spinel or semi-anti-spinel structure; second, because the distance between a B site and another adjacent B site cation is much smaller than the distance between the adjacent A site cations, the electron transition occurs between the B ions, so there must be conductive ions of the same element or different elements at the B site at the same time; third, the B site ions must be variable-valence ions. If the above three conditions are met, NTC thermistor ceramics can conduct electricity.

    In addition, the new study mentioned that the grain boundaries of NTC thermistor ceramics are also conductive, and this inference has also been proven in practice. NTC thermistors are semiconductor sensitive ceramics whose resistivity decreases as the temperature rises.

    The resistance of NTC thermistors varies from 0.2Ω to 1MΩ at room temperature, and the temperature coefficient is -2% to -6%. NTC thermistors can be widely used in surge current suppression, temperature measurement, temperature compensation, temperature sensing and other occasions by utilizing their different characteristics.

    With its unique process methods and leading technology, Shiheng Electronics produces NT thermistor products with outstanding advantages such as high precision, high reliability and high stability, and is at the leading level in the industry. The NTC thermistor series covers surge suppression, temperature compensation, precision temperature measurement, temperature control and other applications. The power NTC thermistors produced by the company have strong surge current suppression capability. The maximum capacitance in the internal control standard is two levels higher than the standard value. In particular, the B value is large, the residual resistance is small, the same electrical performance is smaller, the power consumption is lower, and the main power product series have passed UL, TUV, and CQC safety certifications. The temperature measurement NTC thermistor products produced by the company have many specifications and models, fast response, and high sensitivity. The main products have all passed UL, TUV, and CQC safety certifications. The MF51, MF52, and MF58 series products have passed AEC-Q200 testing, and the MF58 series products have passed the 100,000 times endurance test in the UL standard. The NTC temperature sensors produced by the company have the advantages of high temperature control accuracy, good batch consistency, good stability, high reliability, and long service life. The various thermistors produced by Shiheng Electronics have excellent performance and are deeply favored by users.