Talking About High Stability And Fast Response NTC Temperature Sensor

With the rapid development of smart homes, the application of NTC temperature sensors is becoming more and more extensive. NTC temperature sensors have high requirements for temperature control points, rapid response to temperature changes, and normal thermal shocks during use. They have high requirements for stability and reliability, so that they can work for a long time without affecting the performance of the sensor, so as to achieve temperature control. Precise detection, control and other functions.

However, many NTC temperature sensor chips are packaged with epoxy resin. When the epoxy resin is at high temperature, it is easy to change the crystal structure of the surface of the NTC chip, and the stability of the product is deteriorated. The chip is encapsulated in a stainless steel protective shell with epoxy resin. The head of the temperature sensor has a relatively large heat capacity. It takes a long time for the temperature sensor to sense temperature changes, and it is difficult to achieve rapid response requirements.

Therefore, Exsense provides a high-stability and fast-response NTC temperature sensor, which is composed of a glass-encapsulated NTC thermistor , connecting leads with the NTC thermal chip, and connecting lead tail connectors. The NTC chip is placed in a high thermal conductivity protection In the shell, a thermal conductive silicone grease sealing layer is provided at the bottom of the inner cavity of the protective shell, an epoxy resin encapsulation layer for encapsulating the heat-sensitive chip is provided at the inner port of the protective shell, and a thermal insulation layer is provided on the periphery of the lead. The temperature sensor can have excellent anti-stress effect under high and low temperature impact, good stability, and it needs a short time to sense temperature changes, and can achieve the purpose of rapid response. It can be applied to smart home products such as household coffee machines and quick milk warmers.

The following is the preparation method of high stability and fast response NTC temperature sensor:

(1) First connect the NTC thermal chip with silver paste and leads, and then use glass packaging and high temperature sintering for insulation protection.

(2) Impregnate polyimide resin on the connecting leads of the encapsulated NTC thermal chip as a thermal insulation layer, and use polyimide resin to impregnate and insulate the exposed leads except for the welding part.

(3) Put on the copper protective shell, inject thermal conductive silicone grease at the bottom of the copper protective shell to form a thermal conductive silicone grease sealing layer, and finally encapsulate it with epoxy resin to form an epoxy resin encapsulation layer.

(4) Use nylon and glass fiber to carry out the overall connector injection molding, and finally use a current welding machine to weld the lead and the pin to form a temperature sensor.