Today, with the rapid development of smart wearable devices, smart watch has become not only a showcase of routine functions, but also a powerful assistant for health monitoring. Among them, body temperature monitoring, as one of the important indicators of health assessment, has gradually become a standard function of smart watch. In order to improve the accuracy of body temperature monitoring, as a temperature sensing component, NTC thermistor plays a key role in the temperature measurement function of smart watches.

The working principle of NTC thermistor is based on the characteristic that its resistance value changes negative proportion to temperature, and its linear relationship can be used for efficient real-time temperature monitoring in smart watch. NTC is mainly installed in the body temperature monitoring module of smart watch, which is usually composed of NTC thermistor, signal amplification circuit, analog digital converter (ADC) and microprocessor. When the body temperature monitoring function of the smart watch is activated, the thermistor will measure the temperature instantly, and when the user's body temperature changes, the resistance value of the NTC will change accordingly, which will change the voltage or current signal in the circuit. The signal amplification circuit then amplifies the weak voltage or current signal to a range suitable for processing by the analog-to-digital conversion circuit. Subsequently, the analog-to-digital conversion circuit will convert the amplified analog signal into a digital signal for processing and analysis by the microprocessor. Through wireless communication technologies such as Bluetooth transmission, users can know their body temperature status anytime and anywhere with mobile terminals, and realize remote viewing and analysis of data.

In order to assist in product upgrades of smart watch and make the acquisition of body temperature monitoring data more accurate, EXSENSE Electronics Technology Co., Ltd. has launched a self-developed and produced CB series SMD type NTC thermistor for smart wearable. Compared with traditional SMD NTC, this product has the following advantages:

First, high accuracy: The accuracy of this SMD type NTC can reach ±0.3%, which can achieve high and accurate body temperature measurement of smart watch;

Second, fast response: The high sensitivity of CB series SMD thermistor can assist smart watch to quickly and continuously collect body temperature data and complete real-time monitoring;

Third, small size: The small size of the smart wearable NTC makes it easy to integrate into the circuit of the smart watch, reducing the burden of internal assembly space and facilitating the installation of other components.

To sum up, smart watch as portable smart wearable device, provides user with convenient and fast health monitoring means through built-in NTC thermistor for body temperature monitoring. The use of SMD type NTC thermistor for smart wearable to complete temperature measurement can allow smart watch user to detect abnormal body temperature in time, providing an important basis for the prevention, diagnosis and treatment of diseases.