The reason of poor quality thermistors

Thermistor is widely used in various fields such as household appliances, power industry, communications, military science, aerospace, etc., and has a bright future. So what is the reason for the poor quality of the thermistor?

Thermistor's unique grain boundary structure. Under a certain electric field, the grain boundary conduction instantly changes from thermal electron emission conduction to electron tunnel conduction. Its resistance value decreases sharply with increasing voltage and has excellent nonlinear voltammetry characteristics. Then, when there is an overvoltage, the grain-boundary electron tunneling effect suppresses the overvoltage peak growth and absorbs part of the overvoltage amount, thereby protecting the line or equipment.

When thermistor is applied to power lines or electronic circuits, if various types of overvoltages occur frequently, varistor will frequently operate, suppress the overvoltage amplitude and absorb and release surges, and protect electrical equipment and components. This will cause the performance of the thermistor to deteriorate and fail.